8 : : THE LIBRARY OF THE UNIVERSITY OF CALIFORNIA ^^^H PRESENTED BY PROF. CHARLES A. KOFOID AND MRS. PRUDENCE W. KOFOID -- H f). *. ire. HANDBOOK OF HYGIENE AND SANITARY SCIENCE. RICHTER'S CHEMISTRY, A TEXT-BOOK OF INORGANIC CHEMISTRY FOR STUDENTS. By PROF. VICTOR von RICHTER, University of Brcslau. AUTHORIZED TRANSLATION FROM THE THIRD GERMAN EDITION. By EDGAR F. SMITH, M. A., Ph. D., Professor of Chemistry in Wittenberg College, Springfield, Ohio ; formerly in the Laboratories of the University of Pennsyl- vania ; Member of the Chemical Society of Berlin. 12mo. 89 Wood-cuts and Colored Lithographic Plate of Spectra. $2.00 In the chemical text-books of the present day, one of the striking features and difficulties we have to contend with is the separate presentation of the theories and facts of the science. These are usually taught apart, as if entirely independent of each other, and those experienced in teaching the subject know only too well the trouble encountered in attempting to get the student properly interested in the science and in bringing him to a clear comprehension of the same. In this work of PROF. VON RICHTER, which has been received abroad with such hearty welcome, two editions having been rapidly disposed of, theory and fact are brought close together, and their intimate relation clearly shown. From careful observation of experi- ments and their results, the student is led to a correct understanding of the interesting principles of chemistry. The descriptions of the various inor- ganic substances are full, and embody the results of the latest discoveries. In preparation, " ORGANIC CHEMISTRY." By the same author and translator. Nearly ready. P. BLAKISTON, SON & CO., Medical & Scientific Booksellers, 1012 "Walnut Street, Philadelphia. HANDBOOK OF HYGIENE AND SANITARY SCIENCE. BY CI;OR(;K WILSON, M.A., M.D., F.R.S.E., ; FELLOW Ol \17b VI PEEFACE TO THE FIFTH EDITION. the last and present editions these have been omitted, because they are now more fully treated in a small supplementary work entitled Healthy Life and Healthy Dwellings. I have again to express my obligations to the Sanitary Record, and other periodicals and publications, for much valuable information, of which due acknowledgment is made in the text; while my best thanks are due to Dr. Buchanan, the medical officer to the Local Government Board, for kindly favouring me with copies of the recent reports made by the medical inspectors of that Depart- ment, and other official memoranda which are given in the Appendix. 23 CLAREMONT ROAD, LEAMINGTON, October 1883. CONTENTS. CHAPTER I. INTRODUCTORY. PUBLIC HEALTH AND PREVENTABLE DISEASE. PAGE Public Hygiene, definition and scope of . .1 Sanitary Science, Historical Sketch of . .2 during Middle Ages in England . . 4 ,, Seventeenth Century . . 8 Eighteenth Century . . 8 Suppression of Scurvy and Captain Cook's Labours . 9 Jail Fever and John Howard's Labours . .10 Discovery of Vaccination by Dr. Jenner . .11 Other Sanitary Triumphs of Eighteenth Century . 1 2 Health History of Present Century . .12 Increase of Population and Insanitary Conditions . 13 Public Health Legislation . . . .14 Amount of Preventable Disease . . .20 Signs of improvement judged by average Annual Death-rate . . . . .22 Public Health Service . . . .25 Relations of Curative and Preventive Medicine 25 Vlll CONTENTS. CHAPTER II. FOOD. PAGE SECTION I. FUNCTIONS AND CONSTITUENTS OF FOOD . 27 Conversion of Potential Energy of Food into Dynamic Energy . . . . . .27 Organic and Inorganic Constituents . . .27 1. Functions of the Nitrogenous Constituents . 27 Liebig's Doctrines . . . .28 Experiments of Drs. Fick and Wislicenus . 28 Experiments of Dr. Parkes . . .28 Dr. Pavy's Researches . . . .28 2. Functions of the Fatty Constituents . .29 3. Functions of the Saccharine Constituents or Hydro- carbons . . . . .30 4. Functions of Water and Saline Matters . .30 Proportions of the Several Constituents in a Stand- ard Diet . . . . .31 SECTION II. NUTRITIVE VALUES OF FOODS . .31 Dr. Letheby's Table of Nutritive Equivalents . .32 SECTION III. FOOD AND WORK . . .32 Dr. Edward Smith's Estimates for a daily Diet during periods of Idleness . . . .33 Dr. Letheby's Tables for Diets during Idleness, ordinary Labour, and active Labour . . . .33 Daily Requirements of the Body, as shown by the Excretions . . . . .34 Dietaries of Low-fed Operatives . . .35 CONTENTS. IX PAGE Dietaries of Well-fed Operatives ..... .36 Dietaries of Convicts . . ... .36 Relation of Convict-Labour to Diet . . 37 SECTION IV. CONSTRUCTION OF DIETARIES . 38 1. Influence of Sex . . .38 2. Influence of Age . . . .38 3. Selection of Food . . . . .39 Determined by (1.) The relative Proportions of Proximate Con- stituents . . . . .39 (2.) Variety . . . . .39 (3.) Digestibility . . . .40 (4.) Price . . . . .40 4. Number and Distribution of Meals . . 40 5. Climate . . . . . .40 SECTION V. PRESERVED FOODS . . .40 1. Liebig's Extract . . . . .40 2. Preserved Meat . . . . .41 3. Preserved Vegetables . . . .41 4. Preserved Milk . . . . .41 SECTION VI. EXAMINATION OF FOOD . .42 1. Animal Food . 42 2. Flour ... .45 3. Bread ... .45 4. Oatmeal .... .46 5. Milk ...... 46 6. Butter .... .47 7. CliL-c*/ . 47 CONTENTS. PAGE ...... 48 9. Potatoes . . . . . .48 10. Tea . . . . . 48 11. Coffee ...... 48 SECTION VII. THE EFFECTS OF INSUFFICIENT OR UN- WHOLESOME FOOD ON PUBLIC HEALTH . .49 1. Effects of Insufficient Food . . .49 2. Unwholesome Food . . . .52 (1.) Putrid Meat . . . . .53 (2.) Diseased Meat . . . .54 (3.) Unwholesome Fish . . . .56 (4.) Unwholesome Vegetable Food . .56 Spread of Disease through the Agency of Milk . 57 Aphthous Ulceration of the Mouth . . .57 Outbreaks of Scarlet Fever . . . .59 ,, Diphtheria . . . .61 Enteric or Typhoid Fever . .61 Regulations for Cow-sheds and Dairies 62 CHAPTEE III. AIR: ITS IMPURITIES, AND THEIR EFFECTS ON PUBLIC HEALTH. SECTION I. COMPOSITION OF AIR . . .63 SECTION II. IMPURITIES IN AIR, AND THEIR EFFECTS ON PUBLIC HEALTH . . . .64 Different kinds of Impurities . . . .64 1. Air vitiated by Respiration . . .66 Minor Effects thereof 68 CONTENTS. XI PAGE Graver Effects thereof . . . .69 Typhus . . . . . .70 Phthisis and Lung Affections . . .71 Hospital Gangrene and Purulent Ophthalmia . 72 2. Air rendered impure by Sewage and Cesspool Effluvia . . . . .72 Nature of Impurities . . . .72 Effects thereof . . . . .73 Diarrhoea . . . . .74 Enteric or Typhoid Fever . . . .74 Cholera , . . . . .75 Diphtheria . . . . .76 Eisks attending Sewage-irrigation . . 76 3. Effluvia from decomposing Animal Matter . .77 Effects of Effluvia arising from Putrid Kemains . 77 From Graveyards . . . .77 From Manure and similar Manufactories , .77 4. Gases and Vapours given off by Alkali Works ..... 78 Chemical Works . . . .78 Brickfields . . . . .79 5. The Air of Marshes . . . .79 Effects thereof . . . . .79 6. Air-impurities in certain Trades and Occupations . 80 Mining . . . . . . 80 Steel-grinding and other Trades . . .80 Wool-sorters' Disease . . . .81 Dr. Greenhow's Inquiry into the excessive Mortality from Lung-Diseases . . . .82 Mr. Simon's Comments thereon . . .85 Necessity of Sanitary Inspection . . .85 Dr. Ballard's Inquiry concerning Trade Nuisances . 86 Xll CONTENTS. CHAPTER IV. VENTILATION AND WARMING. PAGE Division of Subject . . . , .89 SECTION I. THE AMOUNT OF FRESH AIR REQUIRED . 89 Dr. Parkes' Experiments . - . . .90 Author's Experiments in Prisons . . .90 Dr. Angus Smith's Experiments .. . .91 Dr. de Chaumont's Experiments . . .91 Circumstances in which the amount of Fresh-air Supply must be increased . . . . .92 SECTION II. CUBIC SPACE . . . .93 Petteiikofer's Experiments . . . .94 Difficulties of preventing injurious Effects when the , Cubic Space is small . . . .95 Different Estimates . . . . .95 Summary of Results , . . . .97 Remarks thereon . . . . .98 SECTION III. NATURAL VENTILATION . .99 Forces engaged in . . . .99 Diffusion . . . . . .99 Movements of Air produced by Inequalities of Tem- perature . . . . . .100 Perflation . . . . . .100 Aspiration . . . . . .100 Ventilation by open Windows . . .101 Air-bricks 102 CONTENTS. XI 11 PAGE Sheringliam Valve . . . . .102 Transverse Ventilating Shafts . . .102 Mr. Tobin's System . . . . .102 Cowls . . . . . .103 Louvres ...... 103 Mr. Sylvester's Plan . . . . .103 Dr. Arnott's Plan . . . . .104 Mr. Potts's Plan . . . . .104 Mr. Varley's Plan . . . . .104 Mr. M'KinnelTs Plan . . . .105 Dr. Stallard's Plan 105 SECTION IV. ARTIFICIAL VENTILATION AND WARMING . 106 Propulsion and Extraction, or the plenum and vacuum Systems . . . . . .106 Ventilation by open Fire-places . . .106 Movement of Air in a Koom with an open Fire-place . 106 Amount of Heat which passes up the Chimney . 108 Galton's Ventilating Stoves . . . .108 Boyle's Ventilating Grates . . . .109 Shorland's Manchester Grate . . . .109 Smoke-consuming Grates " . . . .110 Economisers . . . . . .110 Gas Stoves . . . . . .111 Faults of Common Stoves . . . .111 Construction of Stove Smoke-flues . . .112 Chimney Ventilators . . . . .112 Fresh-air Inlets and Extraction -flues . . .112 Mr. Ritchie's Plan of Ventilation and Warming . 113 Ventilation and Warming by Hot- water Pipes . .113 Ventilation by Furnaces in Extraction-shafts . .114 Combination of Methods 114 XIV CONTENTS. PAGE Ventilation of Mines . . . .115 Ventilation of Ships . . . .115 Ventilation by Gaslights . . . .116 Extraction by Fan or Screw . . . .117 Ventilation by Propulsion . . . .117 Van Hecke's System . . . . .117 Relative Merits of the two Systems of Ventilation viz. Extraction and Propulsion . . .118 Relative Position of Inlets and Outlets . .118 Construction of Foul-air Flues . . .119 Sectional Area of Inlets and Outlets , 120 CHAPTER V. EXAMINATION OF AIR AND VENTILATION. SECTION I. EXAMINATION AS REGARDS VENTILATING ARRANGEMENTS. . . . .122 Cubic Space . . . . . .122 Relative Position and Size of Outlets and Inlets . 123 Air-currents . . . . . .123 Use of Anemometer . . . . .124 Amount of Fresh-air Supply best* indicated by the Amount found to be issuing through the Outlets . 125 Proper time for Examination . . .126 Method of Procedure . . . .126 SECTION II. EXAMINATION BY THE SENSES . 126 SECTION III. CHEMICAL EXAMINATION . .127 1. Carbonic Acid 127 CONTENTS. XV PAGE Description of Pettenkofer's Method . .127 Dr. Angus Smith's Method . . .132 2. Organic Impurities . . . .133 3. Ammonia . . . . .134 SECTION IV. MICROSCOPICAL EXAMINATION . .135 Pouchet's Aeroscope . . . . .135 SECTION V. EXAMINATION AS REGARDS 1. Temperature . . . . .135 2. Moisture . . . . .135 Dry and "Wet Bulb Thermometers . . .136 Table of Relative Humidity . .137 Concluding Remarks . . . .138 CHAPTER VI. WATER. SECTION I. SOURCES . . . . .139 Rain Water . . . . . .139 Amount of Water derivable from Rainfall, and Condi- tions influencing- the same . . . .140 Water from Wells and Springs . . .141 River Water. . . . .143 Lake Water . . . . . .143 Classification of Potable Waters . . .144 SECTION II. QUANTITY REQUIRED FOR HEALTH AND OTHER PURPOSES . . . . .144 Different Estimates . . . .145 Waste of Water 147 XVi CONTENTS. PAGE SECTION III. MODES OF SUPPLY . . .147 Wells and Borings . . . .147 Artesian Wells . . . . .148 Conditions affecting the yield of Wells . .149 Norton's Tube-well . . . .150 Waterworks . . . . .150 Gathering-grounds . . . . .151 Average Annual Kainfall . . . .152 Channels of Gathering-grounds . . .152 Reservoir . . .. . . .152 Construction and Adjuncts thereof . . .153 Construction of Aqueduct and Distributing Conduits . 154 House Service-pipes . . . . .155 Substitutes for Leaden Pipes . . . .155 Conditions affecting the Size of Conduits . .155 Intermittent and Constant Systems of Supply . .156 Relative Merits and Disadvantages thereof . .156 Waste-preventers . . . . .157 Water-cisterns . . . . .157 Protection of Water-pipes and Mains . , .158 SECTION IV. PURIFICATION OF WATER . . .159 Filter-beds . . . . . .159 Domestic Filters and Filtering Media . . .160 Crease's patent Tank Filter . . . .162 Cleansing of Filters . . . . .162 Clark's Process of Purification . . .162 Porter-Clark Process . . . . .163 Other Purifying Agents . . . .163 SECTION V. SOURCES OF POLLUTION . . .164 How Shallow Wells become polluted . . .164 CONTENTS. XV 11 PAGE How public Supplies become polluted . . 1G6 Dangers of direct Communication of Water-mains with Closets . . . . . .166 Dangers attaching to Cisternage . . .167 Dr. Buchanan's Experiments on In-currents into leaky Mains . ' . . . . . 167 CHAPTER VII. WATER ANALYSIS. SECTION I. COLLECTION OF SAMPLES . . .169 SECTION II. PHYSICAL EXAMINATION . . .171 SECTION III. MICROSCOPICAL EXAMINATION . .172 SECTION IV. CHEMICAL EXAMINATION . . .173 1. Qualitative Examination . . . .173 2. Quantitative Analysis . . . .179 Practical Deductions . . . .195 CHAPTER VIII. IMPURE WATER, AND ITS EFFECTS ON PUBLIC HEALTH. SECTION I. MINERAL IMPURITIES . . .199 Effects of excessive Hardness . . . .200 Goitre ...... 200 Lead-poisoning . . . . .201 SECTION II. VEGETABLE IMPURITIES AND THEIR EFFECTS 202 SECTION III. ANIMAL IMPURITIES . . .203 1. Instances of Propagation of Cholera by means of Polluted Water 204 XV111 CONTENTS. PAGE 2. Propagation of Enteric or Typhoid Fever . .208 (1.) Epidemic at Winterton . . . 209 (2.) Guildford . . .211 (3.) Terling . . .211 (4.) Sherborne . . .212 (5.) Outbreak at Cains College, Cambridge . 213 (6.) Epidemic at Lewes . . . .217 Specific outbreaks of Enteric Fever . .217 (a) Outbreak at Nunney . . .218 (6) Over Darwen . . .218 (c) Lansen . . 219 (d) Caterham . . .220 (e) Bangor . . 223 Outbreak at Evesham due to polluted aerated waters ..... 224 Enteric Fever in Rural Districts . .225 3. Diphtheria . . . . .226 4. Dysentery . . . . .226 5. Diarrhoea ..... 226 Concluding Remarks . . . .227 CHAPTER IX. DWELLINGS. SECTION I SITE . . . . .229 SECTION II. STRUCTURAL ARRANGEMENTS . 231 Foundations . . . . . .231 Drains ...... 232 Cesspools . . . . . .234 Wells . . . . . .235 How to prevent Dampness of Walls . . .235 CONTENTS. xix PAGE Situation and Construction of Water-closets . .230 Ventilation of House-drains, etc. . . .238 SECTION III. DWELLINGS FOR THE POORER CLASSES . 240 Plans and Estimates ..... 240 Dwellings unfit for Habitation . . .242 Dwellings of Rural Labourers . . .244 Surface Crowding in Large Towns . .247 SECTION IV. SANITARY INSPECTION OF DWELLINGS . 248 Diseases traceable to Sanitary Defects . . .248 Sanitary Defects in and around Dwellings . .250 Mode of Inspection . . . . .254 CHAPTER X. HOSPITALS. Preliminary Remarks with regard to Site . .259 SECTION I. PAVILION HOSPITALS . . .260 General Plan ..... 260 Conditions which determine the Size and Form of a Ward . . . . . .262 The Number of Patients . . . .262 The Floor and Cubic Space . . . .262 Remarks concerning the Cubic Space of Workhouses . 262 Floor Space in different Hospitals . . .263 Ventilation and Structural Details of a Ward . .263 Furniture . f . . . .265 Ward-offices . . . . . .266 Administrative Buildings . . .268 Exercising Grounds, etc. . . . .269 XX CONTENTS. PAGE SECTION II. COTTAGE HOSPITALS . . .269 Kegulations and Management thereof . . .270 Cost of . . . . .271 Structural Details . . . . .271 SECTION III. HOSPITALS FOR CASES OF INFECTIOUS DISEASE . . . . .272 Memorandum of Privy Council relating thereto . 272 Conditions affecting Site . . . .273 Katio of Beds to Population . . . .274 Actual Cost of different Hospitals . . .275 Structural Details . . . . .276 Tents and Huts . . . . .280 Ground-plans . . . . .281 Management of Infectious Hospitals . . .284 Ambulances . . . . . .284 Hospital Ships . . . . .285 SECTION IV. MORTUARIES . . .286 Clauses in Public Health referring to . . .286 Cost and Structural Details 287 CHAPTER XL REMOVAL OF SEWAGE. What is meant by the term Sewage . . .288 Mr. Simon's Kemarks on the Prevalence of Filth . 289 Different Methods of Sewage-removal . . .291 SECTION I. THE WATER SYSTEM . .291 Construction of Drains and Sewers . . .292 Pipe-sewers, their Advantages . . .293 CONTENTS. XXI PAGE House-drains . . . . .295 Ventilation of Sewers and Drains . . .295 Flushing of Sewers . . . . .298 Shone's Pneumatic System . . . .300 Traps ..... . 301 Water-closets ..... 304 Trough-closets . . . . .305 Tumbler-closets . . . . .305 Bristol Eject ..... 306 Latrines ...... 306 Intercepting Tanks . . . . .307 Urinals ...... 308 SECTION II. THE PRIVY OR MIDDEN SYSTEM . . 308 SECTION III. THE PAIL SYSTEM . . .310 The Goux System ..... 310 Other Systems . . . . .311 Disposal of Pail-contents and Town-refuse . .312 SECTION IV. THE DRY SYSTEM . . .315 Moule's Earth-closet . . . .316 Other Dry Closets . . . . .318 SECTION V. LIEURNUR'S AND OTHER CONTINENTAL SYSTEMS ..... 319 SECTION VI. SYSTEMS BEST SUITED FOR RURAL DISTRICTS 321 SECTION VII. DISPOSAL OP SLOPS . . .325 Village Drainage . . . . 325 Drainage of Scattered Houses . . . .326 SECTION VIIL PUBLIC SCAVENGING . . .327 Duties of Sanitary Authorities 328 XX11 CONTENTS. PAGE Kemoval of House-refuse . . . .328 Street Scavenging . . . . .330 Advantages of Wood-pavement and Asphalt in Street- construction 331 CHAPTER XII. PURIFICATION AND UTILISATION OF SEWAGE. River-pollution . . . . .332 SECTION I. TOWN-SEWAGE . . . .333 Composition and Amount thereof . . .334 Analysis of Urine and Faeces . . . .334 Manurial Value of . . . .335 SECTION II. SCHEMES FOR THE PURIFICATION AND UTILISATION OF SEWAGE . . .336 1. Precipitation Processes . . . .336 Precipitation by Lime . . . .337 Blyth's Process . . . . .337 Holden's Process . . . . .337 Bird's Process . . . . .338 The A B C " Process . . . .338 The Phosphate Process . . . .3.38 Hille's Process . . . . .339 General Scott's Process . . . .339 Whitthread's Process .... 340 Anderson's Process . . . .340 2. Filtration Processes . . . .341 Simple Filtration . . . . .341 Carbon Filtration, or Weare's Process . .341 Upward Filtration ..... 341 CONTENTS. XX111 PAGE Intermittent Downward Filtration . . .341 How carried on at Merthyr-Tydfil . . .342 Kendal .... 343 3. Irrigation . . . . .' 343 Details concerning Sewage farming . . .344 Table of Average Results of the different Processes . 345 Monetary Details . . . . .347 SECTION III. TREATMENT OF VILLAGE SLOPS . . 349 Various Methods . . . . .349 Denton and Field's Automatic Sewage-meter Tank . 350 Irrigation and Intermittent Downward Filtration . 351 Sub-Irrigation . . . . .351 CHAPTER XIII. THE EFFECTS OF IMPROVED DRAINAGE AND SEWERAGE ON PUBLIC HEALTH. SECTION I. THE EFFECTS OF DAMPNESS OF SOIL . 352 Dr. Buchanan's Inquiries concerning the Production of Phthisis ...... 352 Dr. Buchanan's Conclusions . . . .354 Dr. Bowditch's Researches . . . .355 Other Diseases influenced by Dampness of Soil . 356 SECTION II. SANITARY ASPECTS OF THE WATER-CARRIAGE SYSTEM OF EXCRETAL REMOVAL . . .357 Enteric or Typhoid Fever . . . .357 Influence on general Death-rate . . .359 SECTION III. SANITARY ASPECTS OF SEWAGE IRRIGATION 359 Objections which have been raised not tenable . 360 General Conclusions . 361 XXIV CONTENTS. CHAPTER XIV. PREVENTIVE MEASURES DISINFECTION. PAGE Preliminary Keniarks on Infectious Diseases . .362 Mr. Simon's Views . . . . .365 SECTION I. MODE OF PROPAGATION or EPIDEMIC DISEASES, AND THE PRECAUTIONARY MEASURES INDICATED . 369 Cholera . . . . . .369 Enteric or Typhoid Fever . . . .372 Typhus Fever . . . . .373 Relapsing Fever . . . . .375 Smallpox . . . .375 Scarlet Fever . . . . .377 Measles . . . . . .378 Whooping-cough . . . . .378 Diphtheria. . . . . .379 Diarrho3a . . . . .381 SECTION II. DISINFECTANTS . . . .382 Heat and Cold ..... 383 Charcoal . . . . . ' . 383 Chlorine . . . .. . .384 Nitrous Acid . . . . . .384 Iodine . . . . . .385 Bromine .... 385 Sulphurous Acid Gas . . . .385 Carbolic Acid . . . . .385 Terebene . . . . . .386 Cupralum . . . . .386 Sanitas 387 CONTENTS. xxv PAGE Condy's Fluid . . 387 Chloralum . . . . . .387 Chloride of Liine . . . . .387 M'DougalTs Powder . . 387 Sulphate of Copper . .387 Chloride of Zinc . . . . .388 Ferrous Sulphate . . . . .388 Jeye's Disinfectant . . . . .388 Cooper's Salts . ... 388 Potassium Bichromate . . . .388 SECTION III. PRACTICAL DISINFECTION . . 389 Hygiene of the Sick-room . . .. . 389 Disinfection of Empty Kooms and Uninhabited Places . 390 Disinfection of Clothing, Bedding, etc. . .390 Hot-air Chambers . . . . .391 Disinfection of "Water-closets, Urinals, etc. . .391 Disinfection of the Dead Body . .392 CHAPTER XV. VITAL STATISTICS. SECTION I. SOURCES OF INFORMATION . . . 394 1. The Census . . . . .395 2. Calculated Estimates of Population . .398 3. Registration . . . . .401 () Registration of Births . . .402 (b) Marriages . . . 402 (c) Deaths . 402 SECTION IL CLASSIFICATION 404 SECTION III . ,404 1. P.irtli . . 2. Marriai^e-i ..... -lor, 3. Mortality . . . h><; (1.) Total Annual 1 Vat lira t< . . |o<; (2.) Zymotie IValh r.it.- . . . '.411 (3.) Kate Of Infant Mortality . ! I -J (4.) Death-rate at various Croups of Ages . .411 (5.) Death-rate of Persons engaged in various pations . . . . .413 (6.) Death-rates in tlillVivnt Loral . .Ill (7.) Mortality in relation to Seas . . II.. 4. Longevity . . . . .418 (1.) Mean Age at Death .... (2.) Expectation of Life or Mean After-Lifetime at Various Ages . . . .117 5. Morbidity ..... Concluding Rein . . . .418 CHAPTER XVI. THE DUTIES OF MEDICAL OlTKT.Rs OF IM'.U.TH. Conditions of Appointment . . . .481 Rules and Regulations issued hy Loeal Government Board . . . . . .422 SECTION I. NATURAL CONDITIONS A m HE POPULATION CON \ THE DISTRICT . 425 Geological Conditions . . . .425 To|> ( >L, r ra pineal ,, xxvii PAGE :-I'ly . ... 425 CliinaU- . . . 425 SECTION II. ARTIFICIAL CONDITIONS . . . 426 ati"iis ...... 426 'MY ..... 426 I Tb" .... 427 rage, etc. .... 428 Factories, Workshops, etc. . . .428 SECTION III. VITAL STATISTICS . . . 429 Information with respect to Returns, etc. . . 429 SECTION IV. DUTIES REQUIRED or THE HEALTH OFFICER FOR THE EFFICIENT EXECUTION OF THE SANITARY ACTS . . . . . .433 Practical Hints on the more important Sections of the Public Health Act, 1875 . . . .434 rage and Drainage .... 434 I'rivii-s Wit r-< -Insets, etc. .... 434 Scavenging and Cleansing .... 434 Offensive Ditches and Collections of Matter . .435 r-supply ..... 435 Regulation of Cellar-Dwellings and Lodging-houses . 436 Nuisances ...... 436 Remarks on Overcrowding . . .438 Offensive Trades . . . . .441 Unsound Meat . . . . .445 , Mortuaries, . 446 Other Clauses of PuMir Health Act 1875, of Interest to Medical Oil iltl. . . .449 by PuMi< Il.alth Act 1876 , 450 XXV1U CONTENTS. PAGE Artisans' Dwellings Act, 1875 . . .450 By-laws . . . . . .451 Legal Proceedings . . . . .451 Koutine of Duty . . . . .452 Duties of Sanitary Inspectors . . . .452 Reports . . . . . .456 Official Conduct 457 APPENDIX. OFFICIAL MEMORANDA AND OTHER DATA . . .459 I. The Dairies, Cow-sheds, and Milk -shops Order of 1879 . . . . . .459 II. Memorandum on Hospital Accommodation . 461 III. Ambulances . . . . .461 IV. Rules for the Management of Hospitals for Infec- tious Diseases . . . . .462 V. Memorandum with respect to the Steps to be taken in Places where Smallpox is Epidemic . .463 VI. Memorandum with respect to Public Vaccination . 467 VII. Memorandum with respect to Re- Vaccination . 471 VIII. Memorandum with respect to Vaccination from Calf- Lymph . . . . . . 472 IX. General Memorandum on the Proceedings which are advisable in Places attacked or threatened by Epi- demic Disease . . . . .473 X. Suggestions by the Society of Medical Officers of Health for Preventing the Spread of Infectious or Contagious Diseases . . . .477 XI. Memorandum with respect to Returns of Deaths from Registrars, and Returns of Pauper Sickness from District Medical Officers 480 CONTENTS. XXIX PAGE XII. Memorandum with respect to Annual Reports of Medical Officers of Health . . .482 XIII. Clerk's Return of New Cases of Sickness occurring amongst Paupers . . . .485 XIV. Notice of Cases of Infectious Disease occurring amongst Paupers . . . .486 XV. Statistical Tables arranged by the Society of Medical Officers of Health, London . . . 487 XVI. Comparison of Metrical with English Measures . 499 XVII. List of Apparatus and Re-agents for Analysis . 500 INDEX 503 CHAPTEK L INTEODUCTOEY. PUBLIC HEALTH AND PREVENTABLE DISEASE. PUBLIC HYGIENE may be defined as that branch of sani- tary science which concerns the physical condition of communities. It embraces a consideration of the various influences operating upon society, whether for its material good or its actual deterioration, with the view of extending the former, and preventing, or ameliorating, as far as pos- sible, the effects of the latter. It involves the enactment of laws by which the safety of the whole may be protected against the errors of a part, and, above all, it aims at the prevention of disease by the removal of its avoidable causes. In a wide sense, therefore, the science of public hygiene enlists the services of the people themselves in continuous efforts at self-improvement ; of the teachers of the people, to inculcate the best rules of life and action ; of physicians in preventing as well as curing disease; and of lawgivers, to legalise and enforce measures of health- preservation. But while it is the special province of the medical profession, as guardians of the public health, to study the causes of physical deterioration and disease, and to point out how far these causes may be controlled or averted, the general well-being of the people must mainly depend on their own exertions and self-restraint, Sanitary improvements in man's material surroundings will not compensate for social transgressions against 2 PUBLIC HEALTH AND of morality; for public virtue is essential to public health, and both to national prosperity. The time, however, has gone by when people can be dragooned into cleanliness or be made virtuous by police regulations, and hence it is that the most thoughtful among practical reformers of the present day base their hopes of sanitary progress on the education of the masses as the real groundwork of national health. The people must be taught that good conduct, personal cleanliness, and the avoidance of all excesses, are the first principles of health-preservation ; that mental and physical training- must go hand in hand in the rearing and guidance of youth ; and that morality does not consist so much in a blind observance of the formulae of empty creeds as in a hearty submission to precepts of health. Nor is this all. They must be interested systematically in the general results of sanitary progress, and become more intimately acquainted with the social and material causes by which it is impeded. Unless a knowledge of these fundamental principles of hygiene be widely disseminated amongst them, it is in vain to expect that legislative enactments, however well devised, will succeed in raising the standard of public health to any considerable extent. But there are hopeful signs of progress even in this direction. The teaching of physiology and the laws of health, which is being gradually introduced into many schools, will doubtless be productive of much good amongst the rising generation ; while the large share of attention which the discussion of sanitary questions is already receiving in the public press is the best evidence of the steady growth of intelligent conviction as regards all matters affecting the preservation of health and the prevention of disease. Taking, then, this wide view of the scope of public hygiene, it will, I trust, prove alike interesting and useful if, by way of introduction, I give a brief historical sketch PREVENTABLE DISEASE. 6 of its various phases, and more particularly of its progress during recent years. For sanitary science, in the broad sense of the term, is knit up with the life-history of even' nation, and enters largely into the history of civilisation. It figures prominently in the Mosaic code of the Jewish race, and its instructions and preventive measures, as exemplified in that code, have accounted largely for the greater comparative longevity of the Jews, for their extra- ordinary immunity from the recurring epidemics of the Middle Ages, and for the wide-spread, though silent in- fluence which they have long exercised, and still exercise to the present day. Or let us glance at those grand old Greeks who have left us such a rich store of philosophy, literature, and art. It is true that though their sanitary code, propounded by Lycurgus, was severe and cruel, yet the means which they adopted in the care and cultivation of their bodily phy- sique, and the development of their intellectual faculties, miide them the civilisers of the old world and the exem- plars of modem times. But the Greeks, with all their wisdom and physical culture, knew very little of the causes of disease as it affects communities, and they accepted the terrible epidemics with which they were visited as mani- festations of offended deities, or, at the best, as afflictions which could neither be avoided nor prevented. Their decline and fall as a nation were due to the luxury into which they lapsed, and the lax morality which ultimately became their ruin and opprobrium. Referring, now, to the Romans, the other powerful nation of antiquity, we find that though they contributed but little to sanitary science, they have left some wonder- ful examples of sanitary engineering on a large scale. Their Cloaca Maxima, for example, and the aqueduct for rnnveyiiuj water from the hillsides, some thirty miles from Rome, to the city, were works of such stupendous magni- 4 PUBLIC HEALTH AND tude that they have seldom been equalled or surpassed even at the present day. But the Eoman Empire, like that of the Greeks, was destined to pass away, and those who have studied the social causes of its decay attribute its ultimate decline in no small degree to the epidemics which repeatedly devastated the population in the early centuries of the Christian era. We next pass on to what have been termed the dark or Middle Ages, and to the health history of England. The accounts at first are very meagre, but when they become more numerous and reliable they tell us of frequent visit- ations of plague, pestilence, and famine mixed up with stories, strange and incredible, of armies fighting in the air, showers of blood, terrible earthquakes, and the like all of them showing how deep-rooted was the belief in the supernatural as regards epidemic disease and its causes. If, however, we look at the habits and habitations of our forefathers, we have no difficulty in accounting for the fearful mortality which prevailed amongst them. Personal cleanliness was utterly neglected. Clothing was immo- derately thick and warm, and was seldom changed night or day. The diet was coarse, consisting chiefly of flesh meats highly seasoned. Strong wine or ale was drunk early in the morning, and often far into the night ; in short, gluttony and intemperance were prominent charac- teristics of the sturdy fighting Briton of mediaeval times. Then, as regards his dwelling, we find that the towns and villages were composed for the most part of hovels, with mud walls and thatched roofs. " The floors of the houses," to quote from a well-known letter of the learned Erasmus, " were generally made with loam strewn with rushes, constantly put on fresh without removing the old, lying there in some cases for twenty years, concealing fish bones, broken victuals, and other filth," so that one can quite credit him when he says farther, " If even PREVENTABLE DISEASE. 5 twenty years ago I had entered into a chamber which had been uninhabited for some months, I was immediately seized with fever." The streets were unpaved, generally covered with clay and rushes, concealing all sorts of abominations ; moreover, they were dark, narrow, and tortuous, and without sewers or drains. The rural popu- lation, on the other hand, were scattered in slight hovels over wild woods, dreary wastes, and undrained marshes, so that ague and rheumatism were always rife amongst them, and in times of scarcity, which were common enough, they were sure to suffer from famine. Add to all this, that there was constant fighting of some sort going on. Kings were warring against powerful subjects or foreign foes. Cities and towns w r ere walled-in fortresses ; and the roads were beset with marauders and highwaymen. Dogberries watched the streets but did not ward them, bravoes stabbed, burglars were plentiful, and amongst all classes life was held very cheap. Those, indeed, were days in which Mr. Darwin's doctrine of survival of the fittest was exemplified to the fullest extent ; the weakly went to the wall, and left, on the whole, only those of iron constitutions to perpetuate a brave, hardy, and push- ing race, which increased in numbers slowly, if at all, for centuries. We thus see that conditions inimical to health were abundant everywhere. The walled-in cities were highly favourable to overcrowding and stagnant air; the large armies, which were in constant motion, conduced greatly to the spread of epidemic disease ; while personal un- cleanliness and intemperate habits made the people ready victims of disorders of all kinds. It is not surprising, therefore, that fevers and devastating epidemics were prevalent ; and as instances in point, I may mention the following, which are recorded on the authority of Dr. Guy in his excellent work on Public Health : For 6 PUBLIC HEALTH AND example, in the twelfth century, there were fifteen wide- spread epidemics and many famines ; in the thirteenth century, twenty epidemics and nineteen famines ; and in the early part of the fourteenth century there were eight epidemics and more famines. And these epidemics, it should be remembered, were not local outbreaks appearing only here and there, but they spread so far and wide that each and all of them were regarded as visitations of national disaster. And now we come to the fatal year of 1348, when the Black Death or Great Mortality, as it was called, first appeared in England. It is believed to have been an aggravated outbreak of the Oriental Plague, which was then devastating Europe as it had devastated the East. It was an eminently contagious disease imported, no doubt, in the first instance ; but when once it gained a footing on our shores, it spread with such terrible rapidity, that within a few months almost every town and village throughout the country had been attacked, and in some places only a fourth part of the inhabitants were left alive. In London alone 100,000 fell victims to the dis- ease, and 50,000 corpses were interred in one burial- ground, heaped together, layer upon layer, in large pits. Throughout Europe it has been estimated that twenty-five millions, or a fourth part of the entire population, were swept away. Imagination fails to realise the misery and horrors of the time. The sick died untended, charity was dead, and hope extinguished everywhere there was terror and black despair. Without noticing other epidemics which followed the epoch of the Black Death, the next great pestilence which ravaged the country, and known as the Sweating Sickness, broke out in 1485. Unlike the Black Death and the Oriental Plague, which reappeared in the sixteenth and seventeenth centuries, it did not originate in a foreign PREVENTABLE DISEASE. 7 country to be conveyed by infection to our own shores, but it sprang into existence in this, and was no doubt generated and propagated by the insanitary conditions of dwellings and towns, and the filthy and intemperate habits of the people. For the most part it attacked robust middle-aged adults, men fond of good living, and those amongst the poorer classes who were described as " idle persons, good ale drinkers, and tavern haunters." Its onset was quick and its termination rapid, the victim generally dying within twenty-four hours ; while the mor- tality was so great that in many parts of the country half of the male adult population were swept away. During the latter part of the fifteenth century, and the first half of the sixteenth, this pestilence reappeared no less than five times, its last visitation having occurred in 1551. Yet it must .not be forgotten that this sixteenth century, with its long list of ravaging diseases, gave us, neverthe- less, the heroes of the Elizabethan age, our triumph over Spain, and our English Reformation. But progress in sanitary defence was slow, tedious, and tentative. Indeed, the extraordinary vitality and indomitable pluck of the English race would almost appear to have been the sole defences against national decay and disaster, for during long years to come there was but little improvement in the homes or habits of the people. It was not until the Plague, which was the next great pestilence after the Sweating Sickness, had repeatedly devastated the country, and the great fire which swept away the crowded and filthy homes of London in 1666 occurred, that people began to appreciate, though in a faint and glimmering way, the principles of prevention. The plague died out with the fire, but smallpox, jail fever, malignant sore throat, ague, scurvy, and other controllable diseases, still continued to contribute to the excessive mortality of the seventeenth century. 8 PUBLIC HEALTH AND But now we come to the dawn of a better day. The gradual improvements in agriculture, manufactures, and commerce were adding steadily to the comforts of life. Food was becoming more plentiful, and the diet less coarse. Vegetables, and more especially the potato, were becoming much more generally used ; fresh meat was taking the place of salted meat, which had hitherto constituted such a large part of the English dietary ; while tea and coffee were to some extent replacing the. strong ale and ardent spirits which had formerly proved such a baneful source of disease. People, too, were be- ginning to recognise the value of cleanliness of person and home. The introduction of soap and soda made washing easier, and cotton and linen articles of clothing were gradually coming into more general use. Thus far, then, it may be said that the seventeenth century, although characterised by no great advance in sanitary progress, witnessed, nevertheless, some considerable improvements of an incidental and indirect kind. The gradual emanci- pation from the thraldom of filth had begun, and pre- cautionary measures against the spread of disease in the form of a rough-and-ready system of quarantine were here and there attempted. But the great purifier of the cen- tury was the memorable fire of London, which consumed everything from the Tower to Temple Bar, destroying 81 out of the 97 parishes within the city boundaries, and two of the parishes outside the walls. The old wooden houses with their overhanging stories, and the huge sign- boards swinging across the narrow, winding, filthy, unpaved streets, were swept away ; and though the model city which Sir Christopher Wren had planned was not destined to be realised, better houses were constructed, wider streets laid out, and sanitary conditions in other respects were considerably improved. Coming now to the health history of the eighteenth PREVENTABLE DISEASE. century, we find that three terrible scourges, namely, the Black Death, the Sweating Sickness, and the Plague, have finally disappeared from the bills of mortality. And their disappearance, as we have seen, is not to be attributed to any conscious or well-sustained efforts in the way of prevention, but to the silent influence of the onward pro- gress of civilisation. "We now, however, enter upon an era in which observation and induction begin to play a part in the prevention of human suffering, when the physical causes of disease receive fuller appreciation, and when it is at last recognised that these causes can be inquired into and dealt with in a scientific manner. It is true that the workers were few, but the results of their labours have been fraught with untold blessings to humanity. Fore- most amongst these pioneers of sanitary science we find the honoured names of Captain Cook, John Howard, and the immortal Dr. Jenner ; and now let us glance briefly at the good work which they accomplished. Captain Cook's name is associated with the suppres- sion of the once prevalent disease scurvy ; a disease which, up to the latter half of the eighteenth century, decimated our armies and fleets, and often proved terribly fatal amongst the civil population. It is a disease easily recognised and well defined ; fostered, as many other diseases are, by insanitary conditions ; but its real cause is a diet from which vegetables and fruits have been ex- cluded, and therefore its prevention or cure depends upon a proper supply of vegetable food or vegetable juices. It is true that all this had been known or surmised long anterior to the period in question ; but it was reserved for Captain Cook, in his first voyage of discovery round the world, from 1772 to 1775, to prove beyond a doubt that the disease could be banished from every ship's crew, and that it could be entirely eradicated on land and sea. Hitherto it had been a cause of great mortality amongst 10 PUBLIC HEALTH AND seamen ; and, to quote one instance out of many, in Anson's famous expedition some thirty years previous to that of Captain Cook, out of a total number of 9 hands 600 died before the expedition returned, and chiefly from scurvy. During Captain Cook's three years' voyage, on the other hand, there were only four deaths, namely, three from accident and one from consumption, out of a total number of 118 men. Captain Cook thus earned for himself a foremost place amongst the sanitary re- formers of the eighteenth century ; but the nation took years to learn the lesson which he taught, and many more lives had to be sacrificed before it became compul- sory that lime-juice should form a part of the commis- sariat of every sea-going vessel. Scurvy, too, may now be reckoned among the diseases of the past, although it occasionally reappears, as in the late Arctic expedition, but only through blamable neglect or some other mishap. The next great reformer, deserving of special notice, was the great and good John Howard. His name, as every one knows, is associated with the prevention of a fatal disease, then known as the jail-fever, which was constantly breaking out in prisons all over the country, had often invaded our courts of law, and made several assizes memorable as the Black Assizes, and which was continually spreading by means of infection, through the agency of discharged prisoners and debtors, amongst all classes of the community. The disease has long since been recognised to be the same as typhus fever, and John Howard lived the life of an apostle and died a martyr in proving that it is a disease which is essentially due to filth and overcrowding. Without enlarging on the inci- dents of his self-sacrificing labours, the outcome of them is simply this that for years back the prisons of this country have been proved by the most rigid statistics to be far healthier than our homes, and that so-called pre- PREVENTABLE DISEASE. 11 rentable disease of any kind is of such rare occurrence within their walls, that when any isolated cases do appear they at once give rise to surprise, and are sure to call for inquiry. The next great sanitary triumph of the eighteenth century calling for special notice was the discovery of vaccination. That most hideous and terribly fatal disease, smallpox, had long been a terror and scourge to all classes of the community here and abroad, and after the disappearance of the Plague became the severest epidemic of the country. The introduction of the practice of inoculation at the instance of Lady Mary Wortley Montagu, the wife of the English Ambassador at Con- stantinople, which took place somewhere about the year 1720, while it modified the severity of the disease, assisted rather than otherwise its spread. But whether this was so or not, we find from the bills of mortality of the time that during the ten years 1771 to 1781 small- pox was the cause of 100 out of every 1000 deaths in London, and there is reason to believe it was quite as fatal in other parts of the country. The practice of vaccination, Jenner's grand discovery, was commenced in the year 1796, and although it was several years after- wards before it became general, its value as a preventive measure was not long in declaring itself in a steadily declining mortality. Thus, according to well-authenticated returns, while the mortality was 88 per 1000 deaths in the last ten years of the eighteenth century, it has fallen progressively from 64 to 11 per 1000 deaths during the first six decades of the present century. And if we have still recurrent outbreaks of the disease, it is because there are thousands of people living at the present day who never have been protected by vaccination, and many thousands more who have been imperfectly vaccinated. For it should be remembered that it was not till 1840 12 PUBLIC HEALTH AND that we had any vaccination laws at all; not till 1853 that vaccination was provided gratuitously for the poor ; and not till 1867 that vaccination was made compulsory amongst children generally. We may therefore expect occasional outbreaks, though of constantly decreasing severity, for years to come ; but that the disease can and will be finally eradicated, the belief is as deep-rooted and strong in the minds of medical men and of the educated public of the present day as it was in the stout brave heart of Edward Jenner. In addition to these great sanitary triumphs of the eighteenth century there were others, such as improve- ments in ventilation and better house accommodation, which were also contributing their share in lessening the general death-rate, and especially in the reduction of fevers of all kinds. Diseases amongst infants and young children were much less fatal at the close than at the beginning of the century, while the labours of John Howard were beginning to tell on the home habits of the people, as they had already told on the vast improvement which had been effected in the sanitary condition of prisons and jails. The health of our soldiers and sailors was much better cared for, and the sickness and mortality greatly reduced. Altogether the progress made in the actual prevention of disease was very considerable ; and accordingly we find from the bills of mortality that the death-rate of the city of London, which in the seventeenth century was over 80 per 1000, had been reduced to 50 per 1000, and for some years back it has averaged only 22 per 1000. Coming now to the beginning of the present century, we find the country engaged in that long fierce struggle with France which culminated in the victory of Waterloo ; yet, in spite of the constant drain in men and money, the population kept steadily increasing and the public health PREVENTABLE DISEASE. 13 slowly improving. But outside London there were no large towns teeming with overgrown populations none contained so many as 100,000 inhabitants, and only five exceeded 50,000. By and by, however, there came a sudden and unprecedented change in the social history of the country. The discovery of steam-power opened up new sources of industry of almost unlimited extent and variety. Commerce flourished as it had never flourished before ; wealth accumulated ; work became plentiful ; living became easier ; early marriages were encouraged ; and the rapid increase of population begun then has continued ever since. The population of England and Wales, which, in round numbers, was only ten millions in 1810, had increased to over fifteen millions in 1838 ; and at the present day it amounts to over twenty -six millions. And this enormous increase, it should be re- membered, has taken place almost exclusively in already populous towns, or at centres of industry which speedily became populous. But under what conditions ? For the most part in the dust and din of factories ; the vitiated air of mines ; the stifling atmosphere of workshops ; the bustle of busy warehouses ; and when the day's work was done, in overcrowded houses or underground cellars, heaped together in filthy, narrow, and unventilated streets or reeking back slums. Even in the construction of better class houses the veriest rudiments of sanitation were ne- glected, because they were still but little understood and less appreciated. Instead of municipal control there was general apathy. Sewers had to be constructed, but they were of the worst possible description, uneven, leaky, unventilated, and incapable of being flushed, while the house drains leading into them were quite as faulty and imperfect. Scavenging was neglected, filth accumulated everywhere, cess-pits multiplied, and wells became pol- luted. But why fill up the disgusting details of the 14 PUBLIC HEALTH AND picture ? The mischief was done, and in spite of recent improvements and legislative enactments, it will take years of steady, earnest, sanitary work, and millions of money, to undo it. The money, no doubt, will be forth- coming, and the cleansing of the Augean stables may be accomplished in time ; but the squalor, the misery, the disease, the physical deterioration, and the moral degrada- tion engendered, have imposed a load of vitiated heritage which will tell on generations yet unborn, and which at the present day is crushing thousands of children into an early grave. Meanwhile the Legislature had done nothing, or next to nothing, to mitigate the terrible evils which were fast accumulating. With the exception of the Factory Act of 1833, and the Poor Law Amendment Act of the following year, no public measures of general importance had been attempted, and even these were haphazard and tentative. It is true that here and there local Acts had been applied for and granted by Parliament to empower town authori- ties to provide water-supply and drainage, but it was not till those wonderful series of returns of the Kegistrar- General, and the masterly reports of the late lamented Dr. Farr, began to be published, that public attention became thoroughly aroused. At last, thanks to the incessant labours of Edward Chad wick, Dr. Farr, Dr. Southwood Smith, Dr. Guy, and other pioneers of sani- tary progress, the Health of Towns Commission was appointed, and their first report appeared in 1844, a report in which the relations of cause and effect, as applied to disease, were made so glaring and manifest, that among the intelligent portions of the community there arose a loud cry for legislative interference. Things are still bad enough in the present day, but few can form any adequate conception of the deplorable sanitary condition of the country when that report was published. From PREVENTABLE DISEASE. 15 every large town to which the long list of queries was sent, there came, with but little variation, the same terrible series of replies bad drainage, polluted water, unhealthy houses, overcrowding, filth everywhere ; and, as a consequence, an excessive death-rate, with fever and filth-diseases of every description adding enormously to the death-roll. But so powerful were vested interests, and so strong the opposi- tion to interfere with the liberty of the subject or of cor- porate bodies, that it was not till the country was threat- ened with a second visitation of cholera as severe as the epidemic of 1831, that Parliament became alarmed and passed the Public Health Act of 1848. Under this Act the General Board of Health was constituted, with a staff of inspectors who were empowered to hold public inquiries and report on the sanitary condition of towns which, according to the returns of the Eegistrar- General, showed an excessive rate of mortality. The Act itself was event- ually adopted or enforced in a great many towns through- out the country ; but as it was of a permissive nature, like the great majority of the sanitary Acts which followed it, the beneficial results which might have been expected to accrue from it were long in appearing, and were by no means general. Nevertheless, it originated an era of active sanitary improvement in most of our large towns, and it merits special notice as the first outspoken recognition on the part of the Legislature that the health of the State concerns the statesman. By enabling town authorities to borrow money and spread the expense of public works over a number of years, it removed one of the greatest obstacles to sanitation, and, as a consequence, extensive schemes of sewerage and water-supply were soon under- taken in many parts of the country. But, unfortunately, the engineers of those days largely shared the general ignorance of sanitary principles which then prevailed. Sewers were badly constructed, insufficiently ventilated, 16 PUBLIC HEALTH AND and unfiushed ; many of them, in fact, were elongated cess- pools, and the sewage itself, collected at one or more out- falls, was discharged into the nearest stream, thereby creating a general befoulment of our rivers, which, in spite of numerous injunctions, became so serious as to call for a special Act, which was passed in 187G under the title of the Kivers Pollution Act. Among other Acts which followed the Public Health Act of 1848 may be mentioned the Common Lodging- Houses Act of 1851, the Labouring Classes Lodging- Houses Act of the following year, the Metropolis Manage- ment Act of 1855, and the Nuisances Eemoval Act and the Diseases Prevention Act, both of the same year. But during the interim the nation had been learning another terrible lesson in sanitation. The horrors of the Crimean war, engendered by a faulty commissariat, an utter neglect of scavenging and cleanliness, and an in- credible disregard of the most rudimentary laws of health, at last aroused and excited the public mind to the point of indignation, and so in 1857 was instituted the lloyal Commission on the Health of the Army. Their report, which is still of the greatest value, was soon followed by the reports of the Barrack and Hospital Commission, and of the Commission on the Health of the Army in India, all of which demonstrated in the most complete manner that the sick-rate and death-rate of the army were . culpably excessive ; while the adoption of their recommendations, under the able teaching of the late lamented Dr. Parkes, afforded such conclusive proofs of the grand policy of prevention, that a stimulus to sanitary reform began to permeate the more intelligent classes among the general community which has continued to increase ever since. The powers of the General Board of Health were transferred by Act of Parliament to the Privy Council in 1858, and in the same year the Local Government Board PRKYKNTAttl.F. MBIAJOL 1*7 Act was passed, which consolidated to some extent the previous Sanitary Acts which were in force. The ap- pointment of Mr. Simon as medical officer to the Privy Council, with his able staff of medical inspectors, inaugu- rated a new era in civil life. The material causes of disease were investigated with a minuteness and com- pleteness of detail which could not fail to influence the most sceptical, and the series of reports in which these investigations are embodied and commented on have become the classics of sanitary literature. To any one who takes the trouble to read these reports, it becomes at once apparent that whatever of purely beneficial sanitary legislation which has subsequently come into force has all along been largely indebted to Mr. Simon's foresight and advocacy, based on the inquiries of such able co- adjutors as Seaton, Greenhow, Buchanan, Hunter, Thorne, Netten Kadcliffe, Ballard, and others. Many of these inquiries will be specially alluded to in various parts of this work, but this brief historical sketch would be incom- plete without referring to two discoveries in sanitary science which have already resulted in a vast amount of good, and are destined to be of still greater benefit to the nation. I allude to Dr. Snow's researches with regard to the etiology of cholera (see Chapter VIII.) and the differ- entiation between typhus and typhoid fever as regards causation and symptoms, and this last deserves special notice. About the year 1848, when fever was plentiful enough in all our large towns, and did not spare country villages, L)r. Stewart, so well known for his contributions to sanitary literature, Sir William Jenner, and a few other earnest workers in hospital wards, began to observe that among the numerous cases of so-called typhus which came under their care there were many which presented symptoms of a more or less uniform character, but differ- c 18 PUBLIC HEALTH AND ing in many respects from those which characterised typhus fever. These symptoms soon came to be recog- nised as those of typhoid or enteric fever, and subsequent inquiries have so clearly established the causes and mode of propagation of the fever that it is now regarded as a disease which is entirely preventable, and one which we have every reason to believe will eventually be as com- pletely banished from our midst as the ague, which was once so common and now so rare. But it was urged by many, when this disease came to be talked about and written about, and was frequently found to be due to the entrance of sewer-air into houses, that in sewering a town public authorities only increased the danger, and that the money expended was worse than wasted. It is true that there was some show of foundation for this belief, but it has long since been made clear that any outbreaks of the disease which have been traced to sewer emana- tions were due not to the system itself, but to faulty sanitary engineering. Indeed, in the celebrated report of Dr. Buchanan, who was the inspector appointed to visit a large number of towns and make special inquiry into this subject, there was no point more clearly estab- lished than the remarkable reduction which had taken place in almost all the towns where a system of sewer- age had been carried out. (See Chap. XIII.) Without referring to other important inquiries, such as those relating to unwholesome trades and occupations, food -adulterations, polluted water-supply, overcrowding and unhealthy house-accommodation, milk-contamination, and the wide-spread agency of filth in the causation of disease, we may note in passing the principal legislative measures which have recently been enacted to cope with these evils. And among these may be mentioned the Adulteration of Food and Drink Act of 1860 ; Amend- ments of the Factory Acts; the Sanitary Act of 1866 ; PREVENTABLE DISEASK. 19 the Local Government Board Act of 1871, which vested in one central hoard the powers previously exercised hy the Poor Law Board and the Privy Council ; and the Public Health Act of 1872. This last Act divided the country into urban and rural sanitary districts, and neces- sitated the appointment of medical officers of health and sanitary inspectors ; while the Adulteration of Food Act, which was passed in the same year, authorised the ap- pointment of public analysts. Then followed the Public Health Act of 1875, which consolidated the previously existing sanitary Acts ; and in the same year were passed an amended Adulteration Bill, and the Artisans' and Labourers' Dwellings Act, intended to sweep away the rookeries in our large towns. The Rivers Pollution Act followed in 1876, the Canal Boats Act in 1877, and the Public Health (Water) Act in 1878. Reserving the con- sideration of the strictly medical aspects of these various Acts for a future chapter (see Chapter XVL), it may be remarked in passing that, partly owing to the permissive nature of sanitary legislation, partly to the conflicting opinions and want of harmony, which it is well known have hitherto hampered the policy of the Local Govern- ment Board, and partly to the supineness of Local Authori- ties and their aversion to centralisation and Govern- mental interference, sanitary reform, in spite of all the obligations which the Legislature has imposed, and the measures to carry them out which it has provided, remains, comparatively speaking, at a standstill in many parts of the country. It is true that in many other localities there is abundant evidence of sound sanitary progress, but so long as the Public Health Service is allowed to continue in its present chaotic condition, so long will there be loop- holes for the evasion of duty on the part of sanitary authorities, and inducements to remissness on the part of their officers. 20 PUBLIC HEALTH AND This, however, by the way. Let us now consider for a moment the vast amount of preventable disease with which sanitary science and sanitary legislation had to combat at the date of the passing of the Public Health Act, 1872. It was then estimated by Mr. Simon " That the deaths which occur in this country are fully a third more numerous than they would be if our existing know- ledge of the chief causes of disease were reasonably well applied throughout the country ; that of deaths, which in this sense may be called preventable, the average yearly number in England and Wales is about 120,000; and that of the 120,000 cases of preventable suffering which thus in every year attain their final place in the death- register, each unit represents a larger or smaller group of other cases in which preventable disease, not ending in death, though often of far-reaching ill effects on life, has been suffered. And while these vast quantities of need- less animal suffering, if regarded merely as such, would be matter for indignant human protest, it further has to be remembered, as of legislative concern, that the physical strength of a people is an essential and main factor of national prosperity; that disease, so far as it affects the workers of the population, is in direct antagonism to industry ; and that disease which affects the growing and reproductive parts of a population must also in part be regarded as tending to deterioration of the race. " Then there is the fact that this terrible continuing tax on human life and welfare falls with immense over- proportion upon the most helpless classes "of the com- munity ; upon the poor, the ignorant, the subordinate, the immature ; upon classes which, in great part through want of knowledge, and in great part because of their depend- ent position, cannot effectually remonstrate for them- selves against the miseries thus brought upon them, and have in this circumstance the strongest of all claims on a PREVENTABLE DISEASI . 21 legislature which can justly measure, and can abate, their sufferings. " There are also some indirect relations of the subject which seem to me scarcely less important than the direct. For where that grievous excess of physical suffering is bred, large parts of the same soil yield, side by side with it, equal evils of another kind, so that in some of the largest regions of insanitary influence, civilisation and morals suffer almost equally with health. At the present time, when popular education (which indeed in itself would be some security for better physical conditions of human life) has its importance fully recognised by the legislature, it may be opportune to remember that, throughout the large area to which these observations apply, education is little likely to penetrate, unless with amended sanitary law, nor human life to be morally raised while physically it is so degraded and squandered." (See Thirteenth Report of the Medical Officer of the Privy Council.) . Or, to take another illustration. According to the supplement to the thirty-fifth annual report of the Eegis- trar-General published in 1875, there are fifty-four large tracts of England and Wales whose annual mortality- rate is only 17 per 1000, less by five than the average mortality-rate of the whole country, less by ten than in nine districts, and less by twenty-two than the mortality reigning for ten years in Liverpool. It therefore appears that there are influences inimical to life prevailing to a far greater extent in some parts of the country than in others, and a closer analysis of the national death-register demonstrates still more clearly that this excess of mor- tality is for the most part due to diseases which in other ways are known to be preventable, and which detailed mc-dk-al inspections in various localities, at the instance of the Privy Council and the Local Government Board, have 22 PUBLIC HEALTH AND proved to be dependent upon causes which are not only removable, but whose very existence constitutes an offence against sanitary law. These causes have been grouped by Mr. Simon into two great classes, namely, local conditions of filth and nuisance polluting air and water, and reckless disseminations of contagion ; and as regards both these wide fields of disease -causation, the various enactments embodied in the Consolidated Health Act of 1875 have conferred extensive powers upon sanitary authorities throughout the country to remove the former, and to see that protective measures and penal checks are fully and fairly carried out with regard to the latter. But there are some pessimists who have maintained that because the average death-rate of the country has remained stationary, with comparatively slight fluctuations, at a little over 22 per 1000 from 1841 to 1870, pre- ventive measures and the vast sums which have been expended on sanitary improvements are alike powerless to increase the mean duration of life. They appear to regard the average age at death which prevailed during that period, as the " limit which nature in her wisdom " has prescribed, and that we have no grounds for believing that public sanitation will ever materially lessen the per- sistently heavy death-roll of the nation. But such an argument, as has already been made evident, is based on inferences which a closer analysis of vital statistics proves to be altogether untenable. It has been previously shown, for example, that the death-rate in London has been lowered from 8 per 1000 in the seventeenth century, to 50 per 1000 during the past century, and to 2 2 '4 per 1000 in the decade 1871-80. Then, again, we find that during recent years the death-rate has been very consider- ably lowered in many other towns throughout the country, and that this diminished death-rate has admittedly and unmistakably been brought about by the sanitary improve- PKEVENTABLE DISEASE. 23 ments which have been carried out. This is well illus- trated by the following table given in the Appendix to Dr. Kansome's excellent address on State Medicine, de- livered at the meeting of the British Medical Association in 1877, in which he also proves that in these and other localities where new schemes of water-supply and drainage had been completed, there has been a marked amelioration in diseases classed as preventable : Districts of England and Wales, showing some improvement in the Annual Rate of Mortality in the Three Decades, 1841-50, 1851-60, 1861-70. Enumer- Average Annual Mortality. ated Name of District, etc. Registration County. Popula- tion. Deaths to 1000 living. 1871. 1841-50. 1851-60. 1861-70. North Witchford . Cambridge . 15,585 27 21 20 Whittlesey . Wisbech Cambridge . Cambridge . 7,002 34,209 25 25 23 22 21 20 Orsett . Essex . 13,172 24 21 18 Salisbury Wilts . 9,212 28 24 20 Stoke Damerel Devon 49,449 26 23 21 Wolverhampton . Stafford . 136,053 27 28 24 Coventry Warwick . 40,113 27 25 21 Macclesfield . Chester 59,339 26 25 23 Hull . York . 68,316 31 25 26 Newport Merthyr Tydtil . Crickhowell . Monmouth . Glamorgan . Brecknock . 61,252 104,239 20,147 24 28 27 22 29 25 21 25 23 It is no doubt true that these reductions have been counterbalanced by increased death-rates, chiefly in the newer towns which have sprung up so rapidly in mining and manufacturing districts; but considering the evils attendant upon overcrowding, and the utter neglect of all sanitary principles or precautions, it may be fairly argued that even a stationary average death-rate ought to be accepted as proof of progress. Moreover, it should be borne in mind that organised sanitary supervision and 24 PUBLIC HEALTH AND general local administration do not date further back than the Public Health Act, 1872, and that therefore the results have not yet had sufficient time todieclare them- selves, because the evils to be combated were so enormous, and the supineness to encounter them is in many parts of the country still so apparent. Notwithstanding all this, however, it is satisfactory to note that, apart from a diminution of the death-rate in particular localities, there has been a real and sensible decline in the average re- corded death-rate of England and Wales during the past few years. Thus, while the average annual death-rate during the thirty years 1841-1870 was 22'37 per 1000, the average death-rate during the period 1871-1875 was 22, while during the five years 1876-1880 it had fallen to 20 '8. And this reduction has since been maintained, for, according to the last quarterly returns of the Kegistrar- General for 1882, the mean death-rate of the two years 1881-1882 was 19-3 per 1000, being 2*1 below the mean rate in the preceding ten years, 1871-80. In the words of the Eegistrar-General, this implies " that more than 100,000 persons survived the last two years whose deaths would have been recorded had the average rate of mortality in the preceding decade been maintained." Coincident with a reduction of the general death-rate it is also satisfactory to find from the same returns that the mean annual death-rate from the seven principal zymotic diseases, which had been 3'87, 4'11, and 3'36 per 1000 respectively in the three decades 1851-60, 1861-70,1871- 80, did not exceed 2 '44 in the first two years of the current decade ; while the death-rate from fever alone did not exceed 0*29 per 1000, whereas in the three most recent decades it was equal to 0'91, 0*89, and 0*49 respectively. This remarkable reduction in the death-rate from fever, mostly enteric, affords the strongest possible evidence of the beneficial results which follow in the wake of im- proved sanitation. PREVENTABLE DISEASE. 25 But in order to carry on this combat against prevent- able disease to a successful issue, we want a thoroughly organised P^lic Health Service, with efficiently trained health officers who shall be debarred from private practice, and competent sanitary inspectors, all of them holding permanent appointments under the control of the Local Government Board. We also want hospital accommoda- tion within easy access in every populous district for the isolation of cases of infectious disease, and compulsory and early information of all such cases, and we want, more- over, what is still very hard to get, the active and intelligent co-operation of the people themselves in im- proving and maintaining the sanitary condition of the home and its surroundings. Many, too, look hopefully forward to the vast benefits which would accrue if the relations between the public and medical profession, to which sanitary science owes so much, were entirely altered. Hitherto, the public generally have only enlisted the services of the profession when disease sets in ; but it is contended, and with reason, that it would be a far wiser policy to pay the medical attendant so much a year, and thereby enlist his services in conserving the health of the household. To a certain extent this policy is already carried out in club-practice and provident dispensaries, but there would be no difficulty in carrying it out as regards all classes of the community, if people could only be persuaded that it would be to their ultimate advantage, while the rate of remuneration to be paid to the medical attendant could be easily arranged on a fair and equitable basis. For it need hardly be said that so long as medical men are paid solely and simply for attempting to cure, it is obviously not to their interest to exercise their know- ledge and skill in preventing disease, true though it be that the efforts of the profession generally are seldom lax in controlling those diseases which, without their inter- 26 PUBLIC HEALTH AND PREVENTABLE DISEASE. vention, would be sure to spread. Nor should it be overlooked that there is a long list of other diseases, appertaining to the domain of domestic hygiene, such as those resulting from a vitiated heritage, intemperance, errors in diet, and irregular habits or modes of life, which might be largely controlled if the services of the medical practitioner were thus enlisted in the grand policy of prevention. But, unfortunately, the public credulity in the power of cure still reigns paramount, while their faith in prevention lies practically dormant ; and hence it is that quackery of every description continues to thrive, and the pills and potions which are so extensively adver- tised find a ready sale. This, however, is a matter in which the people themselves must take the initiative, and it has only been adverted to here in order to show how curative and preventive medicine might cordially go hand in hand for the promotion of the public health and the abatement of human suffering. FOOD. 2 7 CHAPTEK II FOOD. SECTION I. FUNCTIONS AND CONSTITUENTS OF FOOD. WITHOUT entering into a discussion of the various cheinico- physical changes which food undergoes in the living body, it may be broadly asserted that its ultimate destiny is the development of heat and other modes of motion, which together constitute the physiological phenomena of animal life. The potential energy with which the food is stored becomes converted into actual or dynamic energy, and is manifested in the body as heat, constructive power, nervo- muscular action, mechanical motion, and the like. But as food also supplies the materials which are requisite for the development and maintenance of the living fabric, as well as for the display of its various kinds of active energy, it may be inferred that inorganic and organic substances are both necessary. The organic alone are oxidisable, or capable of generating force ; while the jn_- organic, though not oxidisable, arejessential to the meta- morphosis of organic matter which takes place in the animal economy. The organic constituents of food are generally divided into nitrogenous, fatty, and saccharine compounds ; and the inorganic into water and saline matters. Both classes of constituents are present in all ordinary articles of diet, whether they be derived from the animal or vegetable kingdom. 1. Functions of tlir Nitrogenous Constituents. The 26 PUBLIC HEALTH AND PREVENTABLE DISEASE. vention, would be sure to spread. Nor should it be overlooked that there is a long list of other diseases, appertaining to the domain of domestic hygiene, such as those resulting from a vitiated heritage, intemperance, errors in diet, and irregular habits or modes of life, which might be largely controlled if the services of the medical practitioner were thus enlisted in the grand policy of prevention. But, unfortunately, the public credulity in the power of cure still reigns paramount, while their faith in prevention lies practically dormant ; and hence it is that quackery of every description continues to thrive, and the pills and potions which are so extensively adver- tised find a ready sale. This, however, is a matter in which the people themselves must take the initiative, and it has only been adverted to here in order to show how curative and preventive medicine might cordially go hand in hand for the promotion of the public health and the abatement of human suffering. FOOD. 27 CHAPTEE II FOOD. SECTION I. FUNCTIONS AND CONSTITUENTS OF FOOD. WITHOUT entering into a discussion of the various chemico- physical changes which food undergoes in the living body, it may be broadly asserted that its ultimate destiny is the development of heat and other modes of motion, which together constitute the physiological phenomena of animal life. The potential energy with which the food is stored becomes converted into actual or dynamic energy, and is manifested in the body as heat, constructive power, nervo- rnuscular action, mechanical motion, and the like. But as food also supplies the materials which are requisite for the development and maintenance of the living fabric, as well as for the display of its various kinds of active energy, it may be inferred that inorganic and organic substances are both necessary. The organic alone are oxidisable, or capable of generating force ; while the IQ- organic, though not oxidisable, are essential to the meta- morphosis of organic matter which takes place in the animal economy. The organic constituents of food are generally divided into nitrogenous, fatty, and saccharine compounds ; and the inorganic into water and saline matters. Both classes of constituents are present in all ordinary articles of diet, whether they be derived from the animal or vegetable kingdom. 1. Functions of the Nitrogenous Constituents. The 28 ^ FOOD. nitrogenous constituents consist of albumen in its various forms, fibrine, syntonin or muscle-fibrine, casein, gluten, legumin, and other allied substances, such as gelatine. Their chemical composition is remarkably uniform, and, as they seem all capable of being reduced by the digestive process to a like condition, they can replace each other in nutrition, though not to an equal extent. Up to a comparatively recent period it was believed that nitrogenous constituents must first be converted into tissue before their dynamical energy can be elicited ; in other words, that muscular force is entirely dependent 011 the metamorphosis of muscular tissue, and that urea, being the product of the change, ought to be regarded as a measure of the force. This was the doctrine taught by the late Professor Liebig, and it was generally accepted by physiologists until Drs. Tick and Wislicenus of Zurich published their famous experiments connected with their ascent of the Faulhorn. While these experiments proved that a nonvnitrogenous diet will sustain the body during severe exercise for a short period, and without any notable increase in the amount of urea, the more carefully con- ducted experiments subsequently made by the late Dr. Parkes showed that possibly the amount of urea is even lessened. If this view were confirmed, Dr. Parkes' infer- ence would be rendered highly probable the inference, namely, that muscle, instead of oxidising during labour, and becoming wasted by losing nitrogen, does in reality appropriate nitrogen, and grows, and that its exhaustion does not depend so much on decay for the time being, as on an accumulation of the oxidised products of other food constituents within its tissues. He takes care to point out, however, that in the long run some decay of muscle does take place, and that the amount of nitrogen must be increased as the work increases. The still more recent researches of Dr. Pavey in the case of Mr. Weston, so well I Li . y- ^ ^JlC ^fft^a^- ?* fat- FOOD. 29 known for his pedestrian feats, appear to indicate that at the commencement of a prolonged muscular effort, the nitrogen excreted is considerably increased, and that sub- sequently it will vary pretty much according to the amount contained in the food consumed from day to day. Judging from these and other experiments,- it would therefore appear that, although the main functions of the nitrogenous constituents of food are the construction and repair of the tissues, they exercise other important func- tions of a regulative and dynamic nature not well defined. There is no doubt that a. certain portion of them is directly decomposed in the blood, and so far they contribute to the maintenance of animal heat and the development of dynamic energy ; but the experiments of Pettenkofer and Voit also tend to show that the nitrogenous substances composing the tissues determine the oxidation of the other constituents, or, in other words, that no manifesta- tion of force is possible without their participation in the process. 4t~^^c^ S-Qjuw***^ *fi afa>^^ <* /$ 2. Functions of the Fatty Constituents. The fact that food containing a large proportion of fatty ingredients is invariably used by the inhabitants of cold countries, indi- ^ cates that these constituents play an important part in the maintenance of animal heat. Indeed, it has been proved by experiment that the respiratory or heat -producing powers of fat are twice and a half as great as those of the ^ other hydrocarbons, as starch or sugar. Fat also takes an active share in the conversion of food into tissue, and aids the removal of effete products from the system. The experi- ments already alluded to likewise show that its oxidation in the blood generates to a great extent the force which is rendered apparent in locomotion or manual labour. Further, its distribution in the tissues gives rotundity to the form, serves to retain animal heat by its non-conduct- ing properties, and greatly facilitates the working of the 32 FOOD. GRS. PER POUND. GRS. PER POUND. Carbon. Nitrogen. /- A- Carbon. Nitrogen Split peas 2699 248 New milk 599 44 Indian meal 3016 120 Skim cheese . 1947 483 Barley meal 2563 68 Cheddar cheese 3344 306 Rye meal 2693 86 Bullock's liver 934 204 Seconds flour . 2700 116 Mutton . 1900 189 Oatmeal . 2831 136 Beef 1854 184 Bakers' bread . 1975 88 Fat pork . 4113 106 Pearl barley . 2660 91 Dry bacon 5987 95 Rice 2732 68 Green bacon . 5426 76 Potatoes . 769 22 White fish 871 195 Turnips . 263 13 Red herrings . 1435 217 Green Vegetables 420 14 Dripping 5456 Carrots . 508 14 Suet 4710 Parsnips . 554 12 Lard 4819 Sugar 2955 Salt butter 4585 Treacle . 2395 Fresh butter . 6456 Buttermilk 387 44 Cocoa 3934 140 Whey . 154 13 Beer and porter 274 1 Skimmed milk 43S 43 As this table contains almost all the articles which are likely to be met with in a common dietary, it becomes no difficult matter to calculate the total amount of carbon and nitrogen which any such dietary yields, and to com- pare the results with other dietaries that have been cal- culated in the same way. It is necessary to add that the nutritive equivalents apply to articles in their uncooked state, and that the meat is boned. SECTION III. FOOD AND WORK. It has already been stated that, in addition to main- taining the body in a healthy state, the potential energy of food is the sole source of the active energy displayed in mechanical motion or work. It therefore follows that the diet must be increased as the work increases ; and the question arises at the outset, What is the minimum FOOD. 33 amount of food on which a man of average size and weight can subsist without detriment to health ? From a large number of observations made by Sir Lyon Play- fair and others on the dietaries of prisons and workhouses, and by the late Dr. Edward Smith on the amounts of food consumed by the Lancashire operatives during the cotton-famine, it would appear, according to Dr. Letheby, that a barely sustaining diet should contain about 3888 grains of carbon and 181 grains of nitrogen. In round numbers, and taking a somewhat liberal view of the question, Dr. Edward Smith has proposed the following averages, as representing the daily diet of an adult man and woman during periods of idleness : Carbon (grains). Nitrogen (grains). Adult man . . 4300 200 Adult woman . 3900 180 Average adult . 4100 190 These are the proportions which, according to Dr. E. Smith's researches, are actually required to avert starva- tion diseases ; and they are represented in the case of a man's diet by 22 oz. of carbonaceous food, with 2'97 of nitrogenous. Taking the mean of all the researches which have been made by eminent physiologists, Dr. Letheby has given the following as the amounts required daily by an adult man for idleness, for ordinary labour, and for active labour : Daily diets for -nous. Carl numerous. Carbon. Nitrogen. Oxs. (irs. Ore. Idleness . . 2'67 19'61\ i 3816 180 Ordinary labour 4 "56 29 '24 I = -] 5688 307 Active labour . 5 '81 34 '97; 1 6823 391 Very often the standard for a healthy adult employed at ordinary labour is stated as 20 grammes of nitrogen, and D 34 FOOD. 300 grammes of carbon, equivalent to 308*6 and 4629 grains respectively. And here it may be observed that the general correct- ness of these averages is fully borne out by the results of the numerous experiments which have been made to ascertain the amount of carbon and nitrogen actually excreted by adult men under different conditions of diet and exercise. These results have also been summarised by Dr. Letheby, and the averages are found to correspond very closely with those just given, thus : Daily Requirements of the Body (LETHEBY). Food. Carbon. Nitrogen. Ozs. Ozs. Grs. Grs. During Idleness \ By dietaries . 2'67 19*61 = 3816 180 as determined J By excretions 278 21*60 = 4199 187 Average 273 20 '60 = 4005 184 Routine work as \ By dietaries . 4 '56 29 '24 = 5688 307 determined J By excretions 4 '39 23*63 = 4694 296 4-48 26-44 5191 302 The first of these averages is represented by 2 Ibs. 2 oz. of bread ; and the second by about 3-J- Ibs., or 1 Ib. of butcher meat with about 4^ Ibs. of bread. The actual amounts of carbonaceous and nitrogenous matters which are consumed by low-fed and well-fed operatives are given in the following tables : FOOD. 35 T ec oT c r-T o co oo O p oS I 2 2 I 1 1 I f I II I II * * ^S f S'T^'T^ -'***> ~ ~ ~ ^ r /J V2 36 FOOD. Daily Dietaries of Well-fed Operatives (PLAYFAIR). Starch Containing Containing Class of Labourer. Flesli- formers. Fats. and Sugar. Carbon- aceous. Nitro"- genous. /^ Carbon. N Nitro- gen. Ozs. Ozs. Ozs. Ozs. Ozs. Grs. Grs. Fully-fed tailors . 4-61 1-37 18-47 21-64 4-61 5136 325 Soldiers in peace . 4-22 1-85 18-69 22-06 4-22 5246 297 Royal Engineers (work) . . . 5-08 2-91 22-22 29-38. 5-08 6494 358 Soldiers in war 5-41 2-41 17-92 23-48 5-41 5561 381 English sailor . . 5-00 2-57 14-39 20-40 5-00 4834 252 French sailor . . 574 1-32 23-60 2670 574 6379 405 Hard - worked weavers . . . 5-33 1-53 21-89 25-42 5-33 6020 375 English navvy (Crimea) . . . 573 3-27 13-21 21-06 5-73 5014 404 English navvy (Railway) . . 6-84 3-82 27-81 37-08 6-84 8295 482 Blacksmiths . . 6-20 2-50 23-50 29-50 6-20 6864 437 Prize-fighters (training) . . 9-80 3-10 3-27 1070 9-80 4366 690 Mean of all . . 5-81 2-42 18-63 24-31 5-81 5837 400 Mean of low-fed operatives 3-04 0-64 21-18 22-78 3-04 4881 214 As an addendum to these data, and by way of con- trast, I may here give some particulars with reference to the dietaries of the convicts confined in English prisons. In the hard-labour prisons, where the great majority of the prisoners are employed at active outdoor work, there are two scales of diet viz. the light -labour diet, and the full-labour diet. When medical officer to the Ports- mouth Convict Prison, I carefully calculated the nutritive values of the various articles of food contained in these diets, according to the equivalents given in a preceding table, and the results were as follows : DAILY AVERAGE. Light-labour diet Full-labour diet Carbon, Grs. Nitrogen, Grs. 4651 224 5289 255 FOOD. 37 What is called light labour applies to manual work requiring very little muscular exertion, while full labour embraces a variety of occupations, such as tailoring, shoe- making, artisan work, and navvy work. From the aver- ages already given, it will be inferred that the light-labour diet was quite sufficient for the easy nature of the work, and, practically, with few exceptions, this was found to be the case. The prisoners employed at light labour were all more or less invalid or crippled, and although almost all of them could have taken more food, they were not found to lose weight, except in isolated cases. With regard to the practical working of the full-labour diet, however, this much could not be said ; for while prisoners employed at comparatively easy labour, such as artisan work, did not lose weight to any extent, those employed at the more arduous kinds of labour, such as navvy work, almost invariably lost a great deal, and after a time had In be removed to lighter work to recruit. In whole gangs of prisoners employed at filling and wheeling barrows of clay, for example, I found an average loss of weight of over 1 3 Ibs. per prisoner, the loss accruing within a period of about two months after they had been put to such work. The consequence was that the convicts had to be continuously shifted from hard to lighter work, and, after recruiting, from lighter to hard, otherwise they would have completely broken down, on account of the insufficiency of the full -labour diet for the severer kinds of prison labour. In military prisons, according to Dr. Letheby, where the dietary contains as much as 5090 grains of carbon and 256 grains of nitrogen daily, even for short periods of confinement, many of the prisoners lose weight, and give evidence of other signs of decay, so that it is found necessary to increase the diet for longer periods to 62 Drains of carbon and 317 of nitrogen. Of course military prisoners require more food than convicts, hide- 38 FOOD. pendently of the nature of the work at which they may be employed, inasmuch as they are larger men, and the ordinary physiological wants of the body demand a pro- portionately greater amount of nutriment. But the differ- ence in stature between the two classes of prisoners does not account for such a difference in diets, and I have no doubt that convicts employed at active outdoor labour would require at least as much as is represented by the average diet for ordinary labour given by Dr. Letheby viz. a diet containing 5688 grains of carbon and 307 grains of nitrogen daily, to maintain them in good health, and prevent serious loss of weight. SECTION IV. CONSTRUCTION OF DIETARIES. By reference to the numerous data already given, it will not only be easy to calculate the nutritive value of any given dietary, but a reliable opinion may be formed as to its suitability as well as sufficiency under specified circumstances. It now remains to point out the more important principles which ought always to be kept in view in the construction of dietaries ; and, apart from the influence of work, which has already been considered, they may be briefly summarised as follows : 1. Influence of Sex. In the case of in -door opera- tives, the dietaries of women should be about one-tenth less than those of men. 2. Influence of Age. Up to nine years of age a child should be dieted- chiefly on milk and farinaceous sub- stances. At ten years of age it will require half as much nutriment as a woman ; and at fourteen quite as much as a woman. Young men who have not reached their full growth, but who are doing the same amount of work as adult men, require more food than the latter. FOOD. 39 3. Selection of Food. This embraces a variety of considerations, such as (1.) The relative proportions of proximate constituents. These have already been shown in Moleschott's num- bers, and they correspond very closely with those given by Dr. Letheby viz. 22 of nitrogenous substances, 9 of fat, and 69 of starch and sugar. "Whether the diet be mixed or purely vegetable the same proportions hold good, and the results of experience prove that they are substantially correct. For example, articles of food which are deficient in one class of constituents are invariably associated with others which contain an excess of them. Thus we have butter, or milk, or cheese, with bread ; bacon with veal, liver, and fowl ; melted butter or oil with fish, and so on. Such combinations are also of great service in aiding the digestibility of food. For reasons to be afterwards stated, every dietary should con- tain fresh vegetables. (2.) Variety of Food. But even when the proper proportions of constituents are provided for in a dietary, it is further necessary that certain articles belonging to the same class be varied from day to day, otherwise the appetite cloys. Beef should alternate with mutton, for example ; or variety may be secured by different modes of cooking the same article. Indeed, it is not too much to say that the art of cookery is a matter of national im- portance, not only because it renders food palatable, but because the more it is studied and practised the greater is the economy which may be effected. It is chiefly in this respect that beverages, condiments, etc., become such valuable dietetic adjuncts. It may here be noted that, in apportioning rations of meat, 20 per cent must be allowed for bone. The loss in weight by cooking varies from 20 to 30 per cent. 40 FOOD. (3.) Digestibility. This also in great measure de- pends upon the mode of cooking. (4.) Price. For much practical information on this and other points, see Dr. Edward Smith's Practical Dietary, or his report on the Food of the Lancashire Operatives, in the Fifth Eeport of the Medical Officer to the Privy Council. 4. Number and Distribution of Meals. Experience teaches that three meals daily are best suited to the wants of the body. Dr. Edward Smith, in his physiological diet of 4300 grains of carbon and 200 of nitrogen, distributes the amounts as follows: Carbon. Nitrogen. grs. grs. oz. oz. For Breakfast . . . 1500 70 = 6 '62 1'04 For Dinner . . . . 1800 90 = 7 '85 1'34 For Supper .... 1000 40 = 4 "52 0'59 Total daily . . . 4300 200 18'99 2'97 5. Climate. Other things being equal, carbonaceous substances ought to contain a preponderance of fatty constituents in cold climates, and of starchy or farina- ceous in warm climates. This also applies to seasonal variations. SECTION V. PRESERVED FOODS. Only a few of these need be mentioned. 1. Extractum Carnis. Liebig's extract is perhaps the best known, but there are several other extracts in the market of almost identical composition. According to Dr. Parkes, Liebig's extract is very restorative, removing all sense of fatigue after great exertion. Its nutritive qualities are inferior to those of ordinary beef-tea, but it can often be taken by an invalid when beef-tea would be rejected ; and it has the further advantage of being readily prepared. FOOD. 41 2. Preserve*/ M>t. Weight for weight, preserved meat is not so nutritious as properly cooked fresh meat, because the process of preservation requires that it should be over-cooked. The great difference in price, however, more than compensates for this slight disadvantage, and on the score of economy alone it deserves to be exten- sively used. Large quantities of it are now consumed in workhouses and asylums. It is best used cold, or warmed and mixed with potatoes and vegetables to form a stew ; or it may be minced and warmed. In Dr. Williams' experiments in the Sussex County Asylum, the patients were allowed amounts equal to the uncooked fresh meat daily ration, with the result of a slight gain in weight in 13 of the 20 experimented on at the end of a month, the weight of the others remaining stationary. Soups of various kinds, fish, poultry, game, are now sold in large quantities as preserved foods, while fresh meat is largely imported from Australia and America in refrigerating chambers. 3. Preserved Vegetables. When fresh vegetables can- not be procured in sufficient quantity, dried vegetables should be employed to make up the deficiency. In lieu of potatoes in the early part of summer, preserved potatoes may be used ; but as they are apt to pall on the appetite, other substitutes, such as a mess of rice and cabbage, pease-pudding, or haricot beans, should be given on alter- nate days. 4. / / Milk. Condensed milk as usually pre- pared consists of pure milk sweetened with a little sugar. As one volume of the condensed milk contains the nutri- tive material of four volumes of fresh milk, it should be diluted with three times its volume of water when used. 42 FOOD. SECTION VI. EXAMINATION OF FOOD. It need scarcely be said at the outset that a thorough practical knowledge of the qualities and appearances pre- sented by the various articles of diet, in their wholesome or unadulterated state, is a necessary qualification for the detection of unwholesome or adulterated specimens. 1. Meat. The characters of good meat may be enumerated as follows : (1.) On section it should present a marbled appear- ance from intermixture of streaks of fat with muscle. This shows that the animal has been well fed. (2.) The colour of the muscle should neither be too pale nor too dark. If pale and moist, it indicates that the animal was young or diseased ; and if dark or livid, it shows that in all probability the animal was not slaughtered, but died with the blood in it. (3.) Both muscle and fat should be firm to the touch, not moist or sodden, and the latter should be free from hsemorrhagic points. (4.) Any juice exuding from the meat should be small in quantity, be of a reddish tint, and give a dis- tinctly acid reaction to test-paper. Good meat should dry on the surface after standing a day or two. The juice of bad meat is alkaline or neutral. (5.) The muscular fasciculi should not be large and coarse, nor should there be any mucilaginous or purulent- looking fluid to be detected in the intermuscular cellular tissue. (6.) The odour should be slight, and not by any means disagreeable. An unpleasant odour indicates com- mencing putrefactive change, or that the meat is diseased. By chopping a portion of the meat into small pieces, and afterwards drenching it with warm water, any unpleasant- ness of odour will be more readily detected. Another FOOD. 43 good plan is to thrust a long clean knife into the flesh, and smell it after withdrawal. When the meat is wasted, pale, flabby, and watery, it indicates that the animal has been suffering from some wasting disease, such as consumption or rot. The ribs should always be examined for pleuritic adhesions, the brain and liver for hydatids, and the lungs for multiple abscesses. But it is seldom that the butcher who wishes to sell diseased meat leaves any of the organs or offal exposed to the risk of detection. As a rule, they are all most carefully concealed or destroyed, and various strata- gems, such as smearing the carcase with melted fat, are adopted to improve the appearance of the meat. If parasitic disease is suspected, the muscular fibre should be examined under the microscope. Cysticerci, though generally visible to the naked eye, 4 can only be accurately detected under a low power, and the booklets should always be seen. In searching for trichina, it should be remembered that the parts most likely to be infected are the diaphragm, the intercostal muscles, and the muscles of the jaw. A low power of 50 to 100 diameters will be found to be sufficient. The most common diseases which render the flesh of animals unfit for human food are pleuro-pneumonia ; phthisis, leading to extreme wasting ; rinderpest, or cattle -plague; anthrax, or malignant pustule; splenic apoplexy or Iraxy in sheep ; foot-and-mouth disease in its last stages ; rot or the fluke disease in sheep ; pig- typhoid; pig -measles in the advanced stage; puerperal fever or dropping after calving; and acute febrile dis- orders from whatever cause. In 1880 a very warm discussion was aroused in con- sequence of the Metropolitan Board of Works sanctioning the sale of the flesh of animals slaughtered for pleuro- pneumonia as fit for human food, and though no doubt 44 FOOD. meat of this description has been eaten in large quantities with apparent immunity, it was urged that in adopting such a course more respect was paid to the views of veterinary surgeons than of medical men. But so far as the duties of medical officers of health are concerned, it will generally be found that, no matter whether the meat is much diseased or not, it is exposed for sale as sound meat, and as it is thus palmed off on the public under a fictitious character, there ought to be no hesitation in condemning it. Very often the defence is set up that the meat is intended for dog's meat; but if evidence is forthcoming that the meat has been dressed in the usual way, there is generally very little difficulty in obtaining a conviction. In cases of suspected dropping after calv- ing, the udders and peritoneal lining should be carefully examined, while in all cases the flanks should be looked to, because it is often in these parts that putrefactive change first sets it. As regards rules for seizure and legal proceedings, see Chapter XVI. Bad meat is usually sodden and flabby, with the fat dirty or gelatinous-looking, and the smell unpleasant or sickly. I may here mention that it is the practice in the City of London to condemn the flesh of all animals infected with parasitic disease, such as measles, flukes, etc.; of animals that may have been suffering from acute, febrile, or wasting diseases ; and of those which have died from natural causes or by accident ; as well as all meat tainted by physic, or in a high state of putrefaction. It is also the practice to condemn the flesh of any animal which has been killed immediately before, during, or immedi- ately after parturition, on the presumable grounds that an animal would not be slaughtered under such circum- stances unless, from some cause or other, death appeared to be impending. FOOD. 45 Bad -smell ing sausages, or sausages which have a nauseous or putrid taste, a very acid reaction, or a soft consistence in the interior, are highly dangerous, and should always be condemned. So too with fish which has become sodden or discoloured, and gives off an offen- sive or arnmoniacal odour. 2. Flour. What is called good household flour or " seconds " should contain very little bran, be quite white, or only slightly tinged with yellow, and should give no acidity or musty flavour to the taste. It should not be lumpy or gritty to the touch, nor should it yield any odour of mouldiness to the sense of smell. When made into a paste with a little water, the dough should be coherent and stringy. The amount of gluten can be ascertained by washing carefully a known quantity of flour, made first into a rather stiff dough, until the water comes off quite clear. The gluten, when baked or dried, should be clean-looking, and should weigh at least 8 per cent of the quantity of flour taken for examination. A good flour will yield 10 to 12 per cent. Bad flour gives a dirty -looking gluten, which is deficient in cohesion, and cannot be drawn out into long threads. Flour is sometimes adulterated with barley -meal, maize, rice, potato -starch, etc. Samples of doubtful quality should therefore be examined microscopically. Fungi, vibriones, and the Acarus farince, are detected in flour which is undergoing putrefactive change. 3. Bread. The crust should be well baked, not burnt. The crumb should not be flaky or sodden, but ^regularly permeated with small cavities. The taste and smell should both be agreeable, and free from acidity. Unless there is a considerable quantity of bran in the flour, the colour should be white, not dark or dirty-looking. Good flour, well baked, yields about 136 Ibs. of bread 46 FOOD. per 100 Ibs. of flour, and adulteration is chiefly directed to increase this ratio by making the gluten hard, and the bread more retentive of water. This the dishonest trades- man effects by adding alum, copper sulphate, or a gummy mixture of ground rice. The bread may be recognised by its becoming sodden and doughy at the base after standing for some time. 4. Oatmeal. Good oatmeal is generally roughly ground, and contains a fair proportion of envelope freed from the husks. If husks are present, the probability is that the meal has been adulterated with barley. The starch should not be discoloured, and the meal itself should be agreeable to the palate. If the meal looks suspicious, it should be examined microscopically. 5. Milk. Pure cow's milk, when placed in a tall narrow glass vessel, should be perfectly opaque, of a full white colour, free from deposit, and should yield from 6 to 12 per cent of cream by volume. When boiled it should not change in appearance, and when allowed to stand for some time there should be no deposit. As it is frequently adulterated with water, the specific gravity is an approximate test of the quality, and hence the use of the lactometer. The specific gravity varies from 1026 to 1035; if it falls below 1026 it shows that the milk is. either very poor, or that a certain amount of water has been added. The following table by Dr. Letheby indicates approximately the amount of water adultera- tion according to the specific gravity and percentage of cream : Specific Percentage Specific Gravity Gravity, volume of cream, when skimmed. Genuine milk . . , . . 1030 12'0 1032 Do. with 10 per cent water 1027 10 '5 1029 Do. ,, 20 1024 8-5 1026 Do. ,, 30 ,, 1021 6-0 1023 Do. 40 ,, 1018 5-0 1019 Do. 50 1015 4-5 1016 FOOD. 47 "When milk is largely adulterated with water, other substances, such as treacle, salt, and turmeric, are some- times added to improve the flavour and appearance ; but, generally speaking, the use of a graduated glass vessel to determine the percentage of cream, and testing the specific gravity, will enable one to give a reliable opinion as to whether the milk is genuine or not. Suspicious samples should be sent to the public analyst for analysis. Milk from diseased animals, or from animals sus- pected of being diseased, should be examined microscopic- ally. In foot-and-mouth disease, blood and pus cells may often be detected, and sometimes casts of the lacteal tubes. In what is called garget or inflammation of the udder, similar abnormal constituents may be detected, while the colostrum, after calving, is composed of agglomerations of fat cells united by granular matter. The normal constituents of milk as seen under the microscope consist of round oil globules enveloped in a cyst and scattered epithelial cells. 6. Butter. Butter should give no unpleasant or rancid taste. Adulteration with water or animal fats is best detected by melting the butter in a test-tube ; the water, salt, or other substances remaining at the bottom. After separation of the casein by melting, good butter is entirely soluble in ether at 65 Fahr., while the fat of beef or mutton dissolves with great difficulty, and leaves a deposit. Adulteration with potato or other starch can be at once detected by iodine. Good butter, when melted, should yield a clear-looking oil, with little deposit of water or other substance. 7. Cheese. The quality of cheese is determined by the taste and consistence. Inferior cheeses are often soft and leathery, owing to the amount of water which they contain. Starch, which is sometimes added to increase the weight, may be detected by iodine. 48 FOOD. 8. Eyys. An average -sized egg weighs about 2 oz. avoir. Fresh eggs, when looked through, are more trans- parent at the centre; stale ones, at the top. In a solu- tion of 1 of salt to 10 of water, good eggs sink, while the stale ones float. 9. Potatoes should be of good size, give no evidence of disease, be firm to the touch, and, when cooked, should not be close or watery. 10. Tea. The bloom or glaze of black and green tea is generally artificial. In the case of black tea, it some- times consists of a coating of black-lead ; and in that of green tea, it is usually a mixture of Prussian blue, tur- meric, and China clay. Both kinds of adulteration are detected by shaking the leaves in cold water, straining through muslin, and afterwards examining the deposit. Inferior mixtures, such as Maloo mixture, Moning congou, Pekoe siftings, etc., are largely imported into this country, and consist of exhausted tea-leaves, leaves of other plants, iron-filings, etc., with only a little good tea. Good tea should yield a pleasant aroma, alike in the dry state and when infused in boiling water, and the flavour of the infusion should be agreeable. If the tea is suspicious, the infused leaves should be spread out and carefully scrutinised, and any powdery deposit examined under the microscope. 11. Coffee. The principal adulteration of coffee is chicory. The adulteration may be detected either by microscopic examination or by sprinkling a portion of the suspected sample on the surface of water, when the coffee will float and the chicory sink. The presence of chicory is also .indicated, if, on opening a packet of coffee, the contents are found to be caked, or show any signs of caking. Amongst other articles of food or drink which are liable to adulteration may be mentioned cocoa, mustard, FOOD. 49 pepper, confections, beer, wine, and spirits ; but without entering farther into this part of the subject, it will be sufficient to point out that any article of food or drink, or any drug which is supposed to be adulterated, should be submitted to a public analyst, on whose report proceedings may be taken under the provisions of the " Sale of Food and Drugs Act, 1875." SECTION VII. THE EFFECTS OF INSUFFICIENT OR UNWHOLESOME FOOD ON PUBLIC HEALTH. 1. The minor effects of insufficient food are generally so intimately associated with those of other causes of disease, that it is impossible to estimate, with any approach to accuracy, their separate influence on public health. For, as Mr. Simon eloquently observes, "Long before in- sufficiency of diet becomes a matter of hygienic concern, long before the physiologist would think of counting the grains of nitrogen and carbon which intervene between death and starvation, the household will have been utterly destitute of material comfort ; clothing and fuel will have been even scantier than food ; against inclem- encies of weather there will have been no adequate pro- tection ; dwelling -space will have been stinted to the degree in which overcrowding produces or increases disease ; of household utensils and furniture there will have been scarcely any, even cleanliness will have been costly or difficult; and if there still be respectful endea- vours to maintain it, every such endeavour will represent additional pangs of hunger. The home, too, will be where shelter can be cheapest bought, in quarters where there is commonly least fruit of sanitary supervision, least drainage, least scavenging, least suppression of public nuisances, least, or worst, water-supply, and, if in town, least light and air. Such are the sanitary dangers to E 5 FOOD. which poverty is almost certainly exposed, when it is poverty enough to imply scantiness of food." And this picture, dark though it may appear, represents the con- dition of thousands who are struggling hard for very existence, and yet are all the while unsolicitous of relief. But when to these are added the numbers that swell the pauper list, and crowd the workhouses, with the famishing and permanently disabled, some conception may be formed of the wide-spread suffering and disease which follow in the wake of actual want. The symptoms of failing health produced by insuffi- cient diet, as observed in individual cases, are somewhat as follows : There is gradual loss of flesh, advancing to extreme emaciation. The pulse becomes feeble, and the complexion sallow. Exertion brings on attacks of palpi- tation, vertigo, and transient blindness, until at last the patient falls a victim to some form of adynamic disease. Of this train of symptoms no more notable example could be quoted than the account given of the sanitary condi- tion of Millbank Prison in 1823. The prisoners confined in this establishment had previously received a daily diet of 31 to 33 oz. of dry nutriment, when it was resolved to reduce this allowance to 21 oz., and to exclude from the diet animal flesh, or nearly so. Hitherto, the prison had been considered healthy, but within a few months after the new diet-scale had been introduced the health of the inmates began to give way, the first symptoms being loss of colour, gradual loss of flesh, and general debility. At last, numbers were attacked with diarrhoea, dysentery, and scurvy, and cases of convulsions, maniacal delirium, and apoplexy, .became common. About 52 per cent of the prisoners were more or less affected in this way ; and to prove that the reduction of the diet was the chief, if not sole cause of the epidemic, the prisoners employed in the kitchen and who were allowed 8 oz. additional bread daily, FOOD. 5 1 continued in good health, while the alarming sick-rate amongst the others was not diminished until the diet was increased. (Carpenter.} Similar observations to these were made amongst the prisoners confined in Fort Sumter during the late Ameri- can war. The diet of the 30,000 inmates consisted of only 11 Ib. meal and- -J- Ib. bacon daily per head, and sometimes this allowance was reduced. As a consequence of this and other deplorable hygienic defects connected with the prison, 10,000 Federals died within a period of less than seven months, the prevailing diseases being- diarrhoea, dysentery, scurvy, and hospital gangrene. (Carpenter.) Again, the terrible mortality which prevailed amongst the British troops in the Crimean war was to a very large extent attributable to the insufficiency of the food supply. Xo extra allowance was granted for the increased exertion and the exposure to cold ; and the result was, that within a few months the deaths from diarrhoea, dysentery, scurvy, and fever, rose to 39 per cent, and in some cases to 73. (Lethely.) As regards the civil population, the history of relaps- ing fever is almost exclusively a history of the ravages of disease arising from destitution ; and the famines of the present century, especially those of 1817 and 1847, need only be referred to as evidence on this point. Further, the connection of scurvy with an insufficient or badly arranged dietary, especially among the sailors of our mercantile marine, has all along been so notorious that the following suggestions regarding sea -diet, recently issued by the Board of Trade, may be fitly quoted here as deserving of careful observance : " DIETARY SCALES. The attention of the Board of Trade having been drawn to the increase of scurvy on board British ships since 1873, a Report on the whole subject ' Sea-scurvy, Food- 52 FOOD. scales, Antiscorbutics ' has been recently prepared and forwarded to the local Marine Boards for their observa- tions. The conclusions arrived at in this Eeport were as follows : (1) That scurvy has been on the increase in British ships since 1873. (2) That lime-juice, of itself, will not prevent scurvy, and that too much reliance is placed on it, to the neglect of varied food-scales. (3) That lime-juice, in connection with fresh or preserved meat and vegetables, may prevent scurvy. (4) That the dietary scale of ships should therefore include a fair pro- portion of fresh and preserved meats, as distinguished from salted meats. (5) That more fresh vegetables should be carried, notably raw potatoes. No satisfactory reason is given why fresh potatoes cannot be carried on board British ships. The allegation that they will not keep good on board ship is clearly disproved by the fact that they do keep on board United States ships, and will keep for a fair time anywhere else. (6) That it is not at present desirable to insert a statutory scale of diet in the articles of agreement with crews serving on long voyages, though it may possibly be necessary hereafter, unless the shipowners themselves move in the matter. The replies received from the local Marine Boards have confirmed these views, especially as regards the articles of diet referred to therein, and superintendents are therefore requested to take every opportunity of urging upon owners of vessels sailing on long voyages the necessity of sup- plying their crews with fresh potatoes, molasses, etc., and a larger supply of fresh or preserved meats, in lieu of salt beef or pork." Report Marine Department, 1883. 2. Unwholesome Food. There is so much uncertainty with regard to the effects of eating what is called unsound meat that Dr. Letheby has observed : " I feel that the question of the fitness of such meat for food is in such an unsettled state that my action in the matter is often very FOOD. 53 uncertain ; and I should like to have the question experi- mentally determined ; for, as it now stands, we are either condemning large quantities of meat which may be eaten with safety, and are therefore confiscating property, and lessening the supply of food ; or we are permitting un- wholesome meat to pass almost unchallenged in the public markets." No doubt, much of the apparent immunity from disease enjoyed by the large numbers who unwit- tingly indulge in unwholesome food at times, is to be attributed to the antiseptic power of good cooking, but there are also many instances on record in which food of the most putrid description is devoured without producing any ill effects. Thus, according to Sir Eobert Chris tison, there are whole tribes of savages who at with impunity rancid oil, putrid blubber, and stinking offal; and in this country game is not considered to be in a fit state for the epicure's table until it is undergoing rapid putrefactive change. Admitting all this, however, there is abundant (-vidence to prove that serious consequences resulting from the use of unsound meat are of frequent occurrence, and in all probability a large proportion of cases of obscure disease owe their origin to the same cause. Moreover, it is but only logical to conclude, from general principles, that, as all diseases must affect the composition of animal flesh, and as active putrefactive change must at all events deteriorate its nutritive value, it is of the utmost import- ance to health that these substances should be obtained in as sound a condition as possible. The following is a brief abstract of the more import- ant facts connected with this part of the subject : (1.) Putrid Meat. On the whole, this may be said t> }e wasteful rather than positively injurious, but there are numerous cases recorded in which it has produced serious disease. Vomiting, diarrhoea, and low fever of a typhoidal type, are the chief symptoms. Putrid sausages 54 FOOD. are especially dangerous. According to an official return, it appears that in Wurtemberg alone, during the last fifty years, there have been 400 cases of poisoning from German sausages, and of these 140 were fatal. (2.) Diseased Meat. Here, again, the evidence is of the same conflicting character. According to Dr. Letheby, enormous quantities of the flesh of animals that died of rinderpest in 1863, and more recently of pleuro-pneumonia, have been sent to the London market, sold, and eaten, without having produced any tangible ill effects. It is also well known that Scotch shepherds indulge largely in Iraxy, or diseased mutton, with ap- parent impunity: and, according to M. Decroix, the whole of the inhabitants of Paris would have suffered during the late siege if diseased meat were to any extent dangerous. In the face of such evidence as this, it really becomes a question of public importance whether the flesh of all animals that have died diseased should be condemned. As a matter of fact, about one-fifth of the meat in the London market, according to Professor Gamgee, is of this description ; and it has been urged that, if it were sold under its true character; and proper precautions were taken with regard to selection and cooking, the ill effects which sometimes attend its use might not occur. It has been urged, too, that though such meat would be of inferior quality, it would be much cheaper, and thus come within the reach of many who are sorely in want of animal flesh, but cannot buy it at its present price. As it is, however, the butcher sells it under a fictitious character, and it is therefore the duty of the health officer to condemn it. In the numerous cases of illness which have been attributed to the use of diseased meat, the symptoms are very similar to those occasioned by the use of putrid meat. The exceptional symptoms apply chiefly to the trans- FOOD. 5 5 mission of specific or parasitic disease. Thus instances have been recorded in which persons have been seized with malignant pustule after eating the meat of animals suffering from anthrax ; and Dr. Creighton, in a paper read before the International Medical Congress, 1881, has aroused grave doubts as to whether tuberculosis may not be transmitted to man through eating the flesh of animals suffering from this disease. Sausages and pork-pies have been frequently known to induce symptoms of irritant poisoning, and this is not to be wondered at, considering the vast quantities of diseased meat that are used up in this way. As regards the development of parasitic disease, reference need only be made to the fact that the Cysticer- cvj celluloses in measly pork produces the Tcenia solium, and that of the ox or cow the Tcenia medio-canellata. The trichina disease, again, which was so prevalent in (lermany and elsewhere a few years ago, is due to the Trichina spiralis in the pig ; while the ccchinoccus disease, so common in Iceland, owes its origin to the flesh of sheep and cattle which have become infested by the toenia of the dog. It appears that all these parasites arc destroyed if the meat is thoroughly cooked before ill ing. One of the most remarkable outbreaks which have recently been investigated in connection with diseased meat occurred among persons attending the sale of the late Duke of Portland's effects at Wellbeck, Notts, in June 1880. Dr. Ballard, who was appointed to conduct the inquiry, found that as many as seventy- two persons wore attacked with intense diarrhoea, with febrile symptoms, after partaking of luncheon, and four of the cases proved fatal. From among the various articles of food or drink which were partaken of at the luncheon, he was able to exclude everything except the ham and beef as being in any way implicated in the production of the disease, 5 6 FOOD. . while other considerations suggested the hams or some of them as being most probably at fault. Microscopical ex- amination of the provisions then showed that the hams were infested not with Trichinae, but with a special Bacillus not previously known ; while numerous specimens of this Bacillus were found in the kidney of one of the fatal cases on post-mortem examination. Further, Dr. Klein, on feeding small animals on portions of the suspected ham, or inoculating them with it, developed in them similar symptoms to those from which the infected persons had suffered, and many of them died with acute inflammatory disease of one organ or another ; while Bacilli, taken from two of the hams and cultivated in white of egg, produced on inoculation similar results. Another outbreak of much the same character was in- vestigated by Dr. Ballard in February 1881, and occurred at Nottingham. In this outbreak it was found that after eating baked pork, fifteen persons were attacked, and one died. In this instance, no specimen of the meat could be obtained, but numerous Bacilli were found in the body of the patient who had died. (Report of the Medical Officer of the Local Government Board, 1881.) (3.) Some kinds of fish, especially in warm weather and in hot climates, have been known to produce very severe symptoms. Thus cases of acute urticaria, with swelling of the tongue, fauces, and eyelids, are frequently due to eating lobsters, crabs, or shell-fish ; while gastro- intestinal irritation, sometimes of almost choleraic inten- sity, is by no means a rare consequence of eating putrid fish of any kind. The disease known by the Spanish name of siguatera is of this description, and is common amongst the crews of vessels doing duty in the tropics when they partake of fish caught at the various stations as a change from the ordinary diet of the ship. (4.) As regards unwholesome vegetable food, it may FOOD. be said that all food of this description which has bt mouldy is dangerous. On the Continent, the ergot oi has been productive of serious epidemics, and in t, country alarming symptoms have frequently followed tlu use of flour which contains the ground seeds of Lolium temulentum, or darnel. In connection with the subject of unsound food, special notice should be taken of the spread of disease through the agency of milk. And, first, it has to be noted that the milk of animals suffering from disease, as from foot-and-mouth disease, though no doubt frequently used with impunity, sometimes produces aphthous ulcera- tion of the mouth and gums, with swelling of the tongue and great foetor of the breath. Dr. Thorne reports an outbreak of this nature (see Twelfth Report of the Medical Officer of Privy Council), and I have myself witnessed a few well-marked cases of this description. Dr. Paine, Medical Officer of Health, Cardiff, found that concurrently with an epidemic of foot-and-mouth disease in the town, a severe form of sore-throat became prevalent amongst children in the infected neighbourhood, and microscopic examination of the milk led him to believe that this was the cause. (Sanitary Record, 1879.) Although it may be quite true that the milk of diseased cows has often been used without producing any appreciable ill effects, still there is always a certain amount of risk, and on that account it cannot be too strongly insisted on that all milk of the kind, or indeed any milk yielded by a cow suffering from any form of disease, should be condemned as unfit for human food. In the Western States of America the milk of cows affected with " the trembles," believed to be produced by feeding on Rhus toxicodendron, has frequently been known to cause severe gastric symptoms amongst children, accom- panied by groat weakness and lowering of the tempera- 58 FOOD. ture (see Medical Times and Gazette, 1868). In this country very strong fears have likewise been expressed by the opponents to schemes of sewage irrigation, that the milk of cows fed on sewaged grass would be unwhole- some and the butter become putrid. But, so far as I am aware, there is no well-authenticated instance of disease having been produced in this way, while I can assert to the contrary that there are large quantities of milk sold daily in and around Leamington obtained from cows fed exclusively on sewaged grass during the summer, and that on every occasion on which samples of the milk have been analysed, it has been found to be richly flavoured and of excellent quality. It may also be noted that several analysts have made repeated experiments with the butter, and have found that it possesses none of those tendencies to putrefactive change which have been so gratuitously attributed to it. But the great danger attaching to milk, as a carrier of disease, depends upon its remarkable powers of absorption and the rapid fermentive or zymotic changes which it undergoes when it becomes mixed with putrefying matter, or tainted with disease -germs. Some few years ago it was proved by Mr. Lawson Tait, and the experiment has since been repeated by others, that milk exposed to the vapour of carbolic acid, for example, will very soon taste strongly of the acid ; and in like manner, if it be kept in any close or badly- ventilated place, where foul odours are perceptible, it will very soon become tainted and unfit for use. Very probably, it is in this way that such fungi as the Oidium lactis, described by Fuchs, Hosier, and Hess- ling, are generated, and it is well known that milk so affected has frequently been the cause of gastric irritation and sharp attacks of vomiting. Moreover, there can be no doubt that much of the infantile diarrhoea, which proves specially fatal during the summer and autumn months, is FOOD. 59 due to milk, which either becomes tainted in this way, or becomes tainted by being put into feeding-bottles which are seldom or never properly cleaned. Indeed, there are so many unseen dangers in the use of milk, especially amongst careless and filthy people, that, to insure safety, it should always be boiled during warm weather, and particularly in districts where foot-and-mouth disease is prevalent. Milk should never be stored in sculleries or larders, or in vessels made of lead or zinc ; in the latter case it speedily absorbs salts of the metal and becomes poisonous. As regards the spread of specific disease, there is now an overwhelming amount of evidence which proves, be- yond dispute, that milk is largely instrumental in propa- gating scarlatina and enteric fever; and amongst other instances may be mentioned the following : The late Professor Bell of St. Andrews has related an outbreak of scarlet fever in that town, which showed very conclusively that the fever was distributed by the milk-carrier, or, what is more probable, that the diseased cuticle from the woman and children who vended the milk actually passed into it, and that in this way the poison was introduced. (Lancet, 1870.) Again, Dr. Taylor of Penrith gives an account of a somewhat similar outbreak, in the British Medical Journal, 1870, where he also reports a group of cases of enteric fever which he believed to be due to specifically infected milk. Further, Dr. Ballard (Lancet, 1870) records an outbreak of enteric fever in Islington, which he attributed to the washing of the milk-cans with water derived from a tank which was found to communi- cate with two old drains, and one of these with the pipe of a water-closet. Whether the milk was adulterated with the same water was not ascertained, but the evidence, both positive and negative, rendered it tolerably certain that the disease was propagated in this way. These out- 6 FOOD. breaks were the first of the kind which were thoroughly investigated, but since then numerous others have been reported ; as, for example, the outbreak at Armley, a village near Leeds, investigated by Dr. Eobinson and Dr. Ballard in 1872 ; an outbreak at East Molesey, near Birmingham, also investigated by Dr. Ballard in 1873; an outbreak at Parkhead, a suburb of Glasgow, investi- gated by Dr. Eussell in 1873 ; and the well-known out- break at Marylebone, London, the real cause of which was, in the first instance, suspected by the late Dr. Murchison and others, and was subsequently investigated in all its intricate bearings by Mr. Netten Kadcliffe, assisted by Mr. Power. In this instance the disease ap- peared within a few weeks in as many as 123 families, of whom 106 obtained their milk from a new milk com- pany ; and Mr. Kadcliffe proved with " a probability amounting for practical purposes to a certainty, that " (1.) The outbreak of enteric fever, which formed the subject of inquiry, was caused by milk infected with enteric fever material. " (2.) That this came from a particular farm. " (3.) That the water used for dairy purposes on this farm contained excremental matters from a patient suffer- ing from enteric fever, immediately before and at the time of the outbreak." (See Mr. Simon's Reports, New Series, No. II.) In a paper read before the International Medical Congress in 1881, Mr. Ernest Hart gave a tabulated account of as many as 71 epidemics due to infected milk, 67 of which had been made the subject of detailed in- quiry since the date of the Marylebone outbreak. Of these 5 were epidemics of enteric fever, 1 4 of scarlatina, and 7 of diphtheria ; while the number of cases traceable to each of these diseases in the various outbreaks was esti- mated at 3500, 800, and 500 respectively. As regards FOOD. 61 enteric fever, the contamination of the milk was in 22 out of the 50 epidemics traced to the use of specifically polluted water for " washing the milk-cans," and no doubt in all of them water was the prime agent in producing the disease. In outbreaks of scarlatina, on the other hand, the milk absorbs the contagium given off by the skin and lungs, and in the majority of recorded outbreaks it has been found that persons employed in the dairy were in attendance on patients suffering from the disease, or that the disease itself existed in the dairy. But with regard to diphtheria, the exact exciting cause has not been so easily traced. In a report presented to the Local Government Board, Mr. Power, in describing an outbreak of diphtheria which occurred in North London in 1878, was led to the conclusion that garget or inflammation of the udder of the cow may have induced the disease, but this conjecture has not been corroborated by other in- quiries. Very probably in diphtheria, the milk becomes sometimes tainted through aerial agency, the breath being the contaminating agent ; and as we know that diphtheria is frequently traced to polluted water, it may be reason- ably supposed that milk tainted with such water would also produce the disease. Kecent outbreaks of diphtheria traced to milk-supplies have occurred in Plymouth, Hen- don, and the north of London. But in addition to diphtheria, certain obscure throat affections have been recently traced to a tainted milk- supply, and notably an outbreak which occurred in Aberdeen in 1881. In this outbreak the sufferers were attacked by severe rigors, followed by febrile symptoms and extreme prostration. The tonsils were slightly en- larged, but there was no false membrane, while a marked feature was the swelling of the glands of the neck and those above the clavicle. Over 300 persons sickened within a short time, and 90 families were attacked out 62 FOOD. of a total of 110 supplied by the same dairy. So soon as the milk-supply was stopped, the farther spread of the disease was at once arrested ; indeed, its disappearance was as sudden as its onset. In this instance the water- supply was obtained from an uncovered cistern in the cow -shed, and on analysis it was found to be polluted ; but though suspicion attached to the water, the abrupt- ness of the outbreak points rather to some temporary tainting agency which was not discovered, although it was found to be connected with minute organisms in the milk. (Sanitary Record, 1881.) Although other serious outbreaks might be quoted, these are sufficient to prove that milk is a far more frequent agent in the spread of disease than is generally suspected ; and, for my own part, I am inclined to be- lieve that many obscure cases of enteric fever, and much of the autumnal diarrhoea, which occur in rural districts, are due to polluted milk. Indeed, several scattered cases of enteric fever have come under my own notice, in which, although there was no evidence to show that the specific virus had been introduced, it was clear enough that the well was contaminated with sewage, and that the milk -cans had been washed with the pol- luted well-water, even if the milk itself had not been diluted with it. So far the inspection of dairies and cow-sheds, under the Code of Eegulations issued by the Privy Council in 1879, has been of very doubtful benefit, and indeed in most parts of the country the code has not been put into operation. The duties ought certainly to be trans- ferred from the County to the Sanitary Authorities. (See Appendix.) EFFECTS OF IMPURE ATR ON PUBLIC HEALTH. 03 CHAPTER III. AIR : ITS IMPURITIES, AND THEIR EFFECTS ON PUBLIC HEALTH. SECTION I. COMPOSITION. j 4 ^ PURE AIR, according to the numerous analyses of Dr. Angus Smith, is composed of 20*99 per cent by volume of oxygen, '033 per cent of carbonic acid, and the rest of nitrogen, watery vapour, and traces of ammonia. With the exception of carbonic acid and aqueous vapour, the relative proportions of the other constituents remain tolerably constant throughout the globe. In this country the amount of oxygen varies from 20*999 per cent in the sea air on the coast of Scotland, to 20*910 in Manchester (luring frost and fog, while the carbonic acid ranges from *03 to *05 per cent. The following averages of analyses, quoted from Dr. Smith's work on Air and Rain, represent the more important variations in the open-air percentages of carbonic acid : Carbonic Acid in 100 parts. Averages. Different parts of Scotland, and at various altitudes . '0336 Perth City and outskirts . . . . "04136 Closer parts of Glasgow .... '0539 Opener parts of Glasgow .... '0461 Suburbs of Manchester .... "0369 Streets of Manchester .... '0403 Open places of London .... '0301 Streets of London ..... "0341 Lake of Geneva (S.iussur.-'s analysis) -0439 64 AIR: ITS IMPURITIES, It also appears that the air of the highest mountains con- tains more carbonic acid, less oxygen, and less organic matter, than the air of plains, and that the quantity of oxygen is always sensibly diminished in the air of towns. The amount of aqueous vapour fluctuates greatly, and is mainly influenced by temperature. At a given tem- perature air cannot contain more than a certain quantity of moisture in suspension, and when it has taken up this quantity it is said to be saturated. In general, the air H contains from 50 to 75 per cent of the amount requisite for complete saturation, the average amount being about 1*46 in 100 parts. If the quantity be not within these limits, the air is either unpleasantly dry or moist. The ammonia, which exists as carbonate, chloride, sulphate, or sulphide, is present only in very minute quantities, and does not exceed one part in a million parts of air. In addition to these ingredients, ozone may perhaps be reckoned as a normal constituent, "and spectroscopic analysis has shown that the salts of sodium are every- where present in greater or less abundance. SECTION II. IMPURITIES IN AIR, AND THEIR EFFECTS ON PUBLIC HEALTH. Preliminary Remarks. Impurities in air may be roughly divided into suspended and gaseous matters. While the presence of suspended matters is rendered familiar to every one in the shining particles which become visible in the direct rays of the sun, the well- known demonstrations by Professor Tyndall with the electric light have shown, perhaps more forcibly than heretofore, their almost universal diffusion. Particles of silica and silicates, of calcium carbonates and phosphates, of iron salts, and, in short, of every chemical constituent AXD THEIR EFFECTS OX PUBLIC HEALTH. 65 of the soil, are lifted by the winds and carried hither and thither. In inhabited places, carbon particles, hairs, fibres of cotton, wool, and other fabrics, starch-cells, etc., are found in great abundance. From the vegetable world are wafted seeds and the dAlris of vegetation, as well as spores, germs, pollen, and volatile substances. In like manner, the animal kingdom supplies germs of vibriones, bacterise, and monads, and particles of decayed or decay- ing tissues, such as epithelium and pus cells. The numerous gaseous matters which pass into the atmosphere, and render it impure, will be more con- veniently noticed in the subsequent remarks concerning overcrowding, aud the injurious effects of different trades and manufactures. But there are other organic vapours arising from the decomposition of vegetable and animal products which merit special attention, as, for example, those contained in the air of marshes and sewers. The exact chemical composition of these vapours still remains a mystery. Equally obscure too is the nature of those organic sub- stances which constitute the specific poisons of contagious diseases. Whether they consist of inconceivably minute particles of decaying matter, or of living microscopic germs ; whether, in some instances, they are conveyed by epithelium and pus cells from the diseased to the healthy, or are condensed with the watery vapour of the atmo- sphere, and thus disseminated ; all these are questions which have yet to be satisfactorily answered. Certain it is, that in a large proportion of cases the atmosphere is made the vehicle of the coutagium or morbific agent, whatever its nature; and hence the paramount importance of adopting such measures as will prevent contamination of the air ; or at all events aid in dissipating or destroy- ing its more noxious impurities. It is true some of the operations of Nature are in themselves calculated to F 66 AIR: ITS IMPURITIES, accomplish this end. Injurious gases become diffused, diluted, or decomposed ; animal emanations are absorbed in the processes of vegetation ; suspended matters are wasjied down by the rains, or fall by their own weight ; while many organic substances are oxidised, and thus rendered innocuous. Were it not for these purifying agencies, which are in constant activity, sanitary measures would prove futile ; and, indeed, they are only successful in so far as they approximate to the preventive and remedial means which Nature employs. 1. Air vitiated ly Respiration. The effete matters thrown off in respiration are carbonic acid, watery vapour, and certain undefined organic substances. According to Dr. Carpenter, who has summarised the results obtained by various physiologists, an adult man, under ordinary circumstances, gives off 1 6 grs. of carbon per hour. In both sexes the amount increases up to about the thirtieth year, but beyond the eighth year the exhalation is greater in males than in females. Dr. ft Parkes has given the average amount of carbonic acid exhaled by an adult in the twenty-four hours as 16 cubic feet, or a little over '6 cubic feet per hour. The quantity of watery vapour thrown off by the skin and lungs varies according to the hygrometric condition of the atmosphere. It has been estimated at from 2 5 to 40 oz. in the 24 hours, and requires, on the average, 210 cubic feet of air per hour to retain it in a state of vapour. The organic matter given off has never been accu- rately determined. It has a very foetid smell, and is but slowly oxidised. It is believed 'to be molecular, and may be said to hang about a room like clouds of tobacco- smoke, and, like tobacco-smoke, the odour is difficult to be got rid of, even after free ventilation has been resorted to. It darkens sulphuric acid, and decolourises solutions of potassium permanganate. When drawn through pure AND THEIR EFFECTS OX PUBLIC HEALTH. water it renders it very offensive. It is certainly nitro- genous, and probably in combination with water, because hygroscopic substances absorb it most readily. According to Lemaire, Trautman, and others, it contains minute cellular bodies named "putrefaction -cells," which have been found to bear a close resemblance to the so-called bacteriform puncta which Dr. Macdonald of Netley has detected in foul water. In sick-rooms it is associated with pus-cells and other emanations of disease. As much as 46 per cent of organic matter has been found in plaster taken from the walls of a hospital ward in Paris. As the ammonia, and more especially the albuminoid, may be taken as an index of the amount of organic im- purities contained in air collected at various places, the following summary of analyses, by Dr. Angus Smith, is instructive : Air obtained from No. of Experi- ments. Free Ammonia. Grains per Million cubic feet. Albuminoid Ammonia. Grains per Million, cubic feet. Total Ammonia. Grains per Million cubic feet. lunellan (on the banks of the Clyde) . . . 1 22-845 60-228 83-073 London .... 18 26780 65-947 92727 Glasgow . 4 34-169 133-264 167-483 A bed-room . . . 3 44-305 104-118 148-423 A midden . . . 3 146-911 181-524 328-435 According to a report on the air of Glasgow by Dr. Russell and Mr. Dunnachie, published in May 1879, nitrogen, as free and albuminoid ammonia, was found to be always in excess in the two centric stations of obser- vation in the city, when compared with analyses made of the air collected at an excentric station, but it was also found that the amount of potential or albuminoid am- monia became much lower in the month of July, clearly showing, especially when the amount of sulphur is taken 68 AIR: ITS IMPURITIES, into account, that both forms of ammonia are "largely derivatives of the rapid combustion of fire applied to wood or coal." These experiments have been confirmed to a certain extent by those which have been carried on for some time back at the observatory of Mountsouris, in the neighbourhood of Paris, and serve to prove that the amount of ammoniU cannot be relied on as an index of the insalubrity of air without taking into account the natural history of each sample. Practically speaking, the amount of organic matter ii in air vitiated by respiration is found to increase as the carbonic acid increases. According to Dr. Parkes it becomes distinctly perceptible to the sense of smell when the carbonic acid, in an inhabited room amounts to '7 per 1000 cubic feet of air a statement which has been frequently verified by other experimenters. *6> Briefly, then, the changes produced in an occupied air-space by respiration and transpiration are the follow- ing: The amount of oxygen is greatly lessened, the carbonic acid and watery vapour are largely increased, ammonia and organic matter are evolved, and suspended matter in the shape of low forms of cell-life and epithe- lium scales is thrown off. The effects of breathing considerable quantities of carbonic acid in air otherwise pure have not yet been determined with sufficient accuracy. Dr. Angus Smith has found that 30 volumes per 1000 cubic feet of air produced great feebleness of the circulation, slowness of the heart's action, aud quickened respiration, but he experienced no discomfort in a soda-water manufactory, where the amount was 2 per 1000 volumes. On the other hand, Pettenkofer and Voit found that no discom- fort was experienced from long exposure when as much 4/ as 10 per 1000 volumes was present. In respired air, however, headache and vertigo are undoubtedly produced AND THEIR EFFECTS ON PUBLIC HEALTH. 69 in many persons when the carbonic acid exceeds 1'5 per 1000 volumes, but probably this is as much due to the presence of organic effluvia, and the diminution in the quantity of oxygen, as to the increase in the amount of carbonic acid. Yet it must be borne in mind that even a small excess of carbonic acid interferes with healthy physiological action, inasmuch as it prevents the sufficient exhalation of the gas itself, and induces an undue accumu- lation of it in the blood. In like manner, the quantity of oxygen absorbed is lessened, and there is consequently a retardation of those oxidising processes which are requisite for the complete elimination of effete matters from the system. But while there is always an increase in the amount of carbonic acid, there is likewise, as already pointed out, a marked diminution in the quantity of oxygen in respired air. Thus Dr. Angus Smith found that the percentage of oxygen in the open air of a suburb of Manchester amounted to 20*96 ; in a sitting room, to 20-89 ; in the pit of a theatre, to 20'74 ; in the Court of Queen's Bench, to 20'65 ; and in the sumpt of a mine, to 20 '1400. It does not follow that, because pain or discomfort is not always experienced in a vitiated atmo- sphere, no harm has been done. The effects may be slowly and imperceptibly cumulative, but they are none the less injurious, and they are now recognised as being amongst the most potent and wide-spread of all the "pre- disposing causes " of disease. Speedily fatal results, arising from overcrowding and the want of fresh air, are familiar to every student of medicine. Out of the 146 prisoners confined in the "Black-Hole of Calcutta," 123 died in one night; and it is significant that many of the survivors afterwards suc- cumbed to " putrid fever." Nor have similar instances been wanting in this country. Of the 150 passengers that were shut up in the cabin of the Irish steamer Lon- 70 AIR : ITS IMPURITIES, donderry, with hatches battened down during a stormy night in 1848, 70 died before morning. No doubt, in these two catastrophes, the direct cause of death was asphyxia, but the fact that " putrid fever " attacked many of those who were carried out alive from the Black-Hole of Calcutta showed that the foetid exhalations to which they were exposed must have aided largely in destroying the lives of the immediate victims. Indeed, it is admitted by all physiologists that the re-breathing of foetid matter thrown off by the skin and lungs produces a kind of putrescence in the blood, in proportion to the amount inhaled and to the period of exposure to its influences. Of this species of poisoning the history of the " Black Assizes," in the sixteenth, seventeenth, and eighteenth centuries, furnishes mauy terrible examples. Jail, or typhus, fever, according to Dr. Murchison, was frequently generated de novo solely in consequence of the disastrous effects of overcrowding and deficient ventilation, and the disease thus generated often spread from the court-house, where the prisoners were tried, to the surrounding popu- lation. "My reader," said John Howard, "will judge of the malignity of the air in gaols, when I assure him that my clothes were, in my first journeys, so offensive, that in a post-chaise I could not bear the windows drawn up, and was therefore often obliged to travel on horseback. The leaves of my memorandum book were often so tainted that I could not use it until after spreading it an hour or two before the fire." Even so late as 1815, Harty showed that typhus was being constantly generated in the prisons of Dublin whenever they became overcrowded with con- victs prior to the periodical transportation of the accumu- lated numbers to a penal settlement. Or, to come to more recent times, one finds Dr. Buchanan reporting to the medical officer of the Privy Council regarding an extensive epidemic in Merthyr-Tydfil in the beginning of AND THEIR EFFECTS ON PUBLIC HEALTH. 7l 1870, that it was true typhus fever, and that he referred it to overcrowding, and to want of ventilation in the houses of the poorer people. Such are some of the more direct and palpable effects of overcrowding and deficient ventilation ; but there are others, perhaps equally grave, though not so well pro- nounced, which cannot be overlooked. All the so-called zymotic diseases, for example, are more specially fatal, and spread with the greatest virulence, in densely popu- lated and badly ventilated districts, and it is in these "fever-nests" that epidemic diseases, which prevail during certain septic conditions of the atmosphere, are attended with the highest mortality and the greatest sick-rate. Of other diseases developed by respired air there can be no question that phthisis pulmonalis holds a prominent /f place on the list. A large mass of evidence has been collected from various sources bearing on this point, but the fact is now so fully recognised by the medical pro- ^ fession generally that a few instances will suffice. In the celebrated report of the Army Sanitary Commission, published in 1858, it was proved beyond all doubt that the excessive mortality from consumption amongst soldiers, and in particular regiments, v/as due to overcrowding and insufficient ventilation. Previous to that inquiry the cubic space per soldier in the barracks of the Foot Guards only amounted to 3 3 1 cubic feet, and the phthisis mor- tality was as high as 13 '8 per 1000. In the Horse Guards, on the other hand, with a space per man of 572 *? cubic feet, the mortality from phthisis did not exceed 7 '3 per 1000. It was found that phthisis prevailed at all stations, and in the most varied and healthy climates, the vitiated air in the barracks being the only condition common to all of them. In consequence of this excessive mortality, the Commissioners recommended that the cubic space allowed per man in barracks should be increased, "Cl .'n++*,t l-**=jUte & 72 AIR: ITS IMPURITIES, and the ventilation improved, with the result that, from the time their recommendations were acted upon, the number of phthisical' cases occurring at all these stations has materially diminished. Similar evidence is afforded by the statistics of the Eoyal Navy, and notably as regards the civil population, in the Eeport of the Health of Towns Commission, published in 1844. Indeed, it has been fully established that not only phthisis, but other lung affections, such as pneumonia and bronchitis, are generated to a large extent under like conditions, and the same may be said of such diseases as scrofula, and others of an adynamic type. When air is vitiated by the exhalations of the sick, as in hospitals, there is a risk of gangrene and erysipelas spreading, especially in the surgical wards. The period of convalescence in many cases is retarded, and the mortality rate increased. Pus -cells and putrefying particles are thrown off from purulent discharges, and, finding a suit- able nidus elsewhere, may communicate a special disease, and thus act as a true contagium. The prevalence of purulent ophthalmia, under certain conditions, and the spread of lung-disease in badly-ventilated ships, when the disease appeared to be propagated from person to person, can only be fully explained on some such theory as this. 2. Air rendered impure ly Sewage and Cesspool Effluvia. Amongst the gases generated by the decomposition of faecal matter, whether occurring in sewers or cesspools, may be enumerated, carbonic acid, nitrogen, sulphuretted hydrogen, light carburetted hydrogen, and ammonium sulphide. Dr. Letheby found that sewage-water, excluded from air, and containing 128 grs. of organic matter per gallon, yielded 1*2 cubic inches of gas per hour during a period of nine weeks. But the amount of gaseous pro- ducts given off under ordinary circumstances must vary greatly, according to the dilution of the sewage, the AND THEIR EFFECTS ON PUBLIC HEALTH. 73 rapidity of flow, temperature, ventilation of the sewers, etc. In comparing the results of analyses made by various chemists, it would appear that the oxygen is diminished, and the carbonic acid greatly increased, but that sulphuretted hydrogen and ammonium sulphide, when present, exist only in very small quantities. The pecu- liarly foetid smell of sewage gas is therefore owing to the presence of organic matter, whose exact chemical com- position, however, has not been determined. Dr. Odling believes it to be carbo-ammoniacal. It is alkaline in re- action, and speedily decolourises solutions of potassium permanganate. According to Dr. Cunningham, it contains distinct bacteria, and other low forms of cell-life. Like other organic effluvia, it promotes the growth of fungi, infects milk, and taints meat. It is doubtful whether the effects of sewer-air upon the health of men employed at work in sewers can be said to be very injurious. Indeed, the researches of Dr. Guy and Parent du Chatelet, at first sight, go to prove that this class of labourers enjoy a marked im- munity from diseases which can be attributed to sewer- emanations ; but, as has been shown by the late Dr. Murchison, there are several elements of error in their statistics which mar their conclusions. For example, Dr. Guy's researches were made before enteric and typhus fever were fully recognised as distinct diseases, and Parent du Chatelet's statistics were not only too scanty for a fair deduction, but the majority of the sewer-men whom he examined had been employed at that special work for only a short period. According to Dr. Murchi- son's experience, enteric fever is by no means uncommon among these men, and Dr. Peacock's inquiries led him to express a similar opinion. But whatever the issue of this question, it seems to be quite certain that constant exposure to sewer-gases diminishes the risk of being in- 74 AIR : ITS IMPURITIES, jured by them. A remarkable instance of this apparent immunity enjoyed by workmen, and the disastrous effects upon those whose exposure to such gases was only casual, is afforded by an event that occurred at Clapham in the autumn of 1829 : 20 out of 22 boys at the same school were seized with violent vomiting, purging, prostration, and fever, within three hours. One boy had been seized with similar symptoms two days before, and died ; an- other also succumbed. So alarming was the outbreak that poisoning was suspected, but, after careful investiga- tion, it was found that the sole cause of disease was to be attributed to the opening of a drain at the back of the house. This drain had been choked up for many years, and had been opened two days before the first illness occurred. The effluvia from the drain were most offen- sive, and the boys had watched the workmen cleaning it out ; none of the workmen, however, were subsequently attacked with any of the symptoms which so seriously affected the boys. (Murchison.) While numerous other instances are recorded of the evil effects of the air of sewers, cesspits, drains, etc., in producing temporary ailments, such as nausea, vomiting, diarrhoea, and headache, the great interest which attaches to this important subject rests on the development and spread of enteric fever. Without entering at present into the discu'ssion as to whether this fever is purely specific, or may be generated de novo, there can be no question that the polluted air from cesspits, drains, and sewers, becomes the medium through which the disease is fre- quently propagated, if not engendered. The sewer -air, laden with morbific ferments or contagia, readily finds its way into houses, more especially in cold weather, on account of its greater tension, and in consequence of badly trapped or imperfectly ventilated drains. It may be inappreciable to the senses, but its baneful effects AND THEIR EFFECTS ON PUBLIC HEALTH. 75 make themselves felt none the less, and frequently exhibit themselves in houses which in other respects are replete with every comfort which wealth can command. Indeed, it would appear that persons of the upper and middle ranks in towns are more liable to be attacked by enteric fever than the poorer classes, and for this reason the houses of the former are more generally connected with sewers, and, either from structure or situation, are of higher elevation, so that the light sewer gases, in obedi- ence to natural laws, are more apt to accumulate in the drains of such houses, and, when the drains are not efficiently trapped or ventilated, to effect an entrance in to the houses themselves. Thus it happens that a system of sanitary engineering, which is intended to prevent, and does prevent, the development of disease, not unfre- quently furnishes the readiest means for its propagation. All this, however, could be frustrated if sewers and drains were always kept properly flushed and well ventilated. Two other points connected with the propagation of enteric fever deserve notice : (1) it seems to be clearly established that the disease may be contracted by in- haling the effluvia, from enteric stools previous to their being disposed of; and (2), that if these stools be thrown into a common privy, the disease is almost certain to be conveyed to others who frequent the privy ; hence the necessity of disinfecting all discharges from the patient so soon as they are passed. (For further remarks on this subject, see Chap. XIV.) Amongst other serious consequences of faecal emana- tions, the occasional spread of cholera, and the occurrence of autumnal diarrhoea, are specially to be noted. The outbreak of cholera in the City of London Workhouse, in July 1866, was shown by Mr. Radcliffe (Ninth Report of Medical Officer of the Privy Council) to have taken place, in all probability, in consequence of a sudden efflux of 76 AIR: ITS IMPURITIES, sewer-air from a drain containing choleraic evacuations. Autumnal diarrhoea, again, is found to prevail when' the season is warm and dry, and more particularly in badly- sewered districts. In speaking of this subject, Dr. Murchison says, that " circumscribed autumnal epidemics of enteric fever are often preceded by an increase of diarrhoea, and the diarrhoea reaches its acme long before the fever does." After heavy falls of rain the sewers become well flushed, and the diarrhoea subsides. In country districts isolated outbreaks of diphtheria, trace- able to cesspool effluvia, are not at all uncommon. In these cases it is generally found that there is a water- closet in the house which itself is badly ventilated, that the soil-pipe is never ventilated, and that the closet drain discharges into a cesspool which is completely covered up, and only cleaned out at rare intervals. The consequence is that any gases generated in the cesspool have no outlet except through the water-closet and into the house, and hence result attacks of diphtheria, ulcerated sore throat, and other badly defined ailments. According to the evidence of Sir Henry de la Beche and Sir Lyon Playfair, in the Second Eeport of the Health of Towns Commission, there are strong presumptive grounds for believing that emanations from streams polluted by faecal matter may be injurious to the health of inhabitants living on their banks. It is stated that many of them were pale, and suffered from dyspepsia, and that cases of fever, when they occurred, were increased in severity. In other instances, however, no such effects have been traced. When sewage matter is thrown over the ground, the exhalations given off have likewise been proved to be sometimes productive of serious disease. Thus, Dr. Clouston has recorded an outbreak of dysentery among the patients in the Cumberland "and Westmoreland Asylum, AND THEIK EFFECTS ON PUBLIC HEALTH. which he attributed to the emanations from sewage applied to the land about 300 yards from the asylum. After this outbreak the sewage was allowed to fall into a small stream, and for two years the asylum had been free from the disease. At the end of this period, however, the sewage was again applied to the farm, and again the dysentery appeared, although all proper precautions were taken in the way of disinfecting and in applying the sewage. It is to be noted that there was a stiff brick- clay subsoil, and doubtless this prevented the sufficient percolation of the sewage into the ground. 3. Effluvia from decomposing Animal Matter. Under this heading may be included the effluvia from decom- posing carcases ; the air of graveyards ; and the effluvia from manure, tallow, and bone- burning manufactories. On almost all these points the evidence is very con- flicting. The preponderance of opinion, however, leaves no room for doubt that the effects of all such effluvia upon the health of the general population, when exposed to their influence, are more or less injurious ; and in support of this view the following amongst many other confirmatory instances may be quoted : (1.) The effluvia arising from the putrid remains of horses killed on the field of battle have frequently given rise to outbreaks of diarrhoea and dysentery amongst the soldiers. In the French camp, before Sebastopol, when numbers of the bodies of horses lay putrefying and un- buried, the effects were so serious that the spread of typhus was supposed to be due to this cause. (Parkes.) (2.) According to the evidence summed up in the Eeport on Extramural Sepulture in 1850, the vapours given off from thickly crowded graveyards, if not actually productive of disease, do certainly increase the sick and death rate of the immediate neighbourhood. (3.) Although the health of workmen employed in 78 AIR: ITS IMPURITIES, manure and similar manufactories does not appear to be injured by their occupation, the occasionally disastrous effects upon others, of the effluvia given off, are well illustrated by the following case : In 1847, many of the inmates of Christ Church Workhouse, Spitalfields, were seized with violent attacks of diarrhoea, of an enteric type. It was found that whenever the works were actively carried on, and particularly when the wind blew from that quarter, there ensued an outbreak of diarrhoea in the workhouse. In December of the following year, when cholera was spreading in the neighbourhood, sixty of the children were attacked one morning with violent diarrhoea. In consequence of this outbreak the owner of the manu- factory was obliged to stop work, and the children rapidly recovered. Five months afterwards the works were re- sumed, and again there was a similar outbreak amongst the inmates occupying the part of the building opposite the manufactory. The works were once more discontinued, and the diarrhoea ceased. (Carpenter?) The effluvia produced in tallow-making and similar trades, though sometimes very offensive, and therefore an undoubted nuisance in inhabited districts, do not appear to have produced any serious effects which have been recorded. According to Dr. Ballard, however, they often induce headache, nausea, and sometimes diarrhoea. (Report of Med. Officer, Local Government Board, 1876.) 4. Gases and Vapours given off by Alkali Works, Chemical Works, and Brickfields. (1.) The principal gas evolved in alkali works is hydrochloric acid. Its effects on vegetation are very destructive, but with proper care in the condensation of the gas, there does not appear to be any evidence to show that works of this description are injurious to the health of those living in the neigh- bourhood. (2.) From chemical works, and especially from those AND THEIR EFFECTS ON PUBLIC HEALTH. 79 in which gas liquor is utilised for the production of salts of ammonia and other chemical compounds, the injurious gases evolved consist chiefly of sulphuretted hydrogen, ammonium sulphide, and traces of other ammonium com- pounds. The workmen -employed at such works appa- rently enjoy good health, but when the noxious vapours are not properly consumed by being collected and passed through a furnace, there is no doubt that they do affect the health of the neighbouring inhabitants, though not to any serious extent. (3.) The peculiarly pungent odour of brickfields can be felt at several hundred yards' distance ; but though several cases are recorded, in which the existence of a nuisance was fully established, none are quoted as having proved that the health of the neighbourhood was affected. 5. The Air of Marshes. This generally contains an excess of carbonic acid, light carburetted hydrogen, watery vapour, sulphuretted hydrogen, and organic effluvia. It also abounds with the debris of vegetable matter, infusoriae, and insects. The more serious and characteristic effects of marsh miasmata are intermittent and remittent fevers. Ail- ments, however, of a less severe nature such as diarrhoea, dysentery, and various other gastric derangements have been attributed to their influence ; and even when no marked signs of disease can be detected, the inhabitants of such districts often present an enfeebled and pallid appearance. The submerging of meadows, draining of lakes, and digging of canals, have all of them been fol- lowed by the development of marsh-diseases, probably on account of the decomposition of vegetable matter which ensues. For the same reason, a long continuance of dry weather, followed by rains, favours the evolution of mias- mata. Fortunately, in this country, marsh-diseases have become comparatively rare, though there is no doubt that 80 AIR: ITS IMPURITIES, in low -lying and badly -drained districts the excessive sick-rate which often prevails is in a great measure owing to atmospheric impurities of a marshy nature. 6. Air -Impurities in certain Trades and Occupations. The deleterious impurities under this heading consist chiefly of mineral and organic substances, as, for example, the particles of coal-dust in the air of mines ; particles of steel and grit given off in grinding ; arsenical fumes, in copper-smelting ; zinc fumes, in brassfounding ; pearl-dust, in button-making ; organic dust or fluff, in shoddy and flax mills, etc. But the whole of this part of the subject is so extensive that only a few instances of the increased sick-rate and mortality produced by these impurities can be given here. The habitual inhalation of coal-dust contained in the air of coal-mines results in what is called the " black- lung ; " the pneumonic cells becoming gradually blocked up, so that, after death, the lung presents a peculiarly melanotic appearance. Cases of emphysema and chronic bronchitis are also very common amongst colliers, and it has been ascertained that the aggregate amount of sick- ness experienced by this class of workmen between the ages of 20 and 60 amounts to 95 weeks, or 67 per cent more than the general average. ( Wynter.) No doubt much of the disease with which miners are liable to be attacked is to be attributed to the baneful effects of in- haling the products of combustion given off by candles, lamps, etc. ; because, when mines are well ventilated, as in Durham and Northumberland, lung affections are much less frequent. But of all unhealthy occupations that of steel-grinders is perhaps the most fatal. Steel-grinding is divided into dry, wet, and mixed ; the injurious effects varying accord- ing to the amount of water used on the stone. Forks, needles, backs of scissors, etc., are all ground on the dry AND THEIR EFFECTS OX PUBLIC HEALTH. 81 stone, and, accordingly, the men and boys employed at this kind of work suffer most. The late Dr. Hall of Sheffield collected a large amount of information bearing upon this subject, from which the following particulars relating to the average duration of life of artisans in steel have been summarised. Dry-grinders of forks, 2 9 years ; razors, 3 1 years ; scissors, 3 2 years ; edge-tool and wool- shears, 3 2 years ; spring-knives, 3 5 years ; files, 3 5 years ; saws, 38 years; sickles, 38 years. Fans, however, are now more commonly used than formerly, while wet- grinding is becoming more general, and as a result of these and other precautionary means the average longevity of Sheffield grinders is increasing. In the pottery trade, the flat-pressers and scourers suffer to such an extent from the effects of the fine dust inhaled, that, according to Dr. Greenhow, almost all of them become eventually asthmatical. Pearl-button makers, and workers in flax or shoddy mills, are all afflicted more or less with bronchial irrita- tion, and many of them with decided lung -disease. Cotton-weavers also suffer very much from the fine dust given off by the " sizing ; " and some time ago an inquiry was made by Dr. Buchanan at Todmorden, which revealed the great prevalency of lung-disease, dyspepsia, and per- manent epistaxis, amongst this class of operatives. Amongst wool-sorters the disease known as anthrax, or malignant pustule, has at times proved very fatal, the poison being conveyed into the system generally by inhalation of the fine dust given off in cleaning the wool, though it also may be conveyed by local inoculation. Two out- breaks have recently been investigated one by Dr. Kussell, Medical Officer of Health for Glasgow; and the other, which occurred at Bradford, by Dr. Spear, Local Govern- ment Inspector. (See Supplements to Local Government Reports for 1878 and 1880.) G &MU * 82 AIR: ITS IMPURITIES, **4-*~ In addition to asthma and bronchitis, brassfounders are very liable to attacks of an affection called " brass- founders' ague," the characteristic symptoms of which present themselves in the following sequence : shivering, nervous depression, marked febrile disturbance, and pro- fuse sweating. Flour-millers, sweeps, and snuff-grinders, are all of them apt to suffer from various forms of asthma. Workers in lead are apt to suffer from " drooping wrist" and lead colic; lucifer-match makers, from necrosis of the lower jaw, caused by phosphorus fumes ; and workers in mercury, from mercurialism. In the Third Eeport of the Medical Officer of the Privy Council, Dr. Greenhow gives the following sum- mary of his inquiry into the excessive mortality from lung- diseases : "This inquiry has demonstrated that an excessive prevalence of pulmonary diseases is associated with a great variety of conditions, some of which must clearly be regarded as exciting causes of these diseases. With respect to others, it has been found impossible to obtain accurate and conclusive evidence that they produce dis- eases of the lungs, but there are strong grounds for sup- posing such to be the case. There is also a third class < of conditions, on which great stress was laid by various medical practitioners, and which may perhaps be regarded as having a tendency to 'produce these diseases. The conclusions deducible from the inquiry may therefore be arranged under the three following heads : V,flT^ " A. Conditions which this inquiry has shown to be direct causes of pulmonary diseases. " B. Conditions so frequently associated with an excessive pressure of pulmonary diseases that they may be regarded as at least indirect causes of these diseases. " C. Conditions which, in all probability, co-operate producing pulmonary diseases, but respecting the in- AND THEIR EFFECTS ON PUBLIC HEALTH. 83 fluence of which no conclusive evidence could be obtained." "A. 1. Inhaling an atmosphere loaded with mechan- ical impurities, such as fine dust of metal, stone, clay, or of certain animal and vegetable [products ; soot, and particles of flax, cotton or woollen fibre, exemplified in the case of grinders of cutlery, needles, and other steel articles ; miners, quarrymen, stonemasons, china-scourers, potters, turners of earthenware, makers of plaster-of-Paris moulds, hacklers of flax and "Mexican fibre; sorters of wool, alpaca, and mohair ; operatives employed in the manufacture of waste silk, and in the carding-rooms of cotton factories ; wool-combers ; workers in bone, ivory, horn, and mother-of-pearl ; and makers of walking-sticks, and wooden handles for cutlery, umbrellas, and parasols. " 2. Inhaling an atmosphere containing carbonic acid or other gases unfit for respiration, or fumes arising from the combustion of gunpowder, or of charcoal, or other fuel, exemplified in the cases of miners and wool-combers. " 3. Inhaling an overheated and highly-dried atmo- sphere, exemplified in the cases of the flat-pressers, and some other workers in potteries. " B. 1 . Habitual exposure, during the hours of labour, to a hot and exceedingly moist atmosphere, exemplified in the cases of slip-makers in potteries and spinners of flax. " 2. Working in ill- ventilated and over-heated fac- tory-rooms, as in many manufactories of textile fabrics, in some of the decorators' rooms of potteries, in ware- houses, and likewise in many establishments where young females are congregated together at work. " 3. Exposure to vicissitudes of temperature, exem- plified in the cases of the operatives in several kinds of factories and workshops. " 4. A stooping or otherwise constrained posture 84 AIR : ITS IMPURITIES, while at work, exemplified in lace-makers, throwers of earthenware, certain classes of weavers, file-cutters, and silk-piercers. " 5. Working continuously many hours daily at a sedentary occupation, such as that of the glove- makers of Yeovil, decorators of earthenware, and welters and finishers of hosiery. "6. Working in ill -ventilated and overcrowded rooms, as in the straw-plat and lace schools of Berkham- stead, Towcester, and Newport Pagnell, the winding- rooms of Leek, and the weaving-shops of Hinckley and Leicester. " 7. Eesiding in dwellings so constructed that the bedrooms are badly ventilated, and the cubical space per head is inadequate to the preservation of health, such as are to be found in Berkhamstead and Saffron Walden. " C. 1. Bleakness of climate, a cold damp soil, pre- valence of fogs. " 2. Marriages of consanguinity. " 3. Habitual abuse of alcoholic stimulants. " 4. Insufficiency of animal food." Although certain parts of this summary have no immediate connection with the subject-matter in hand, it ha,s been given in extenso, to show how frequently several causes of disease co-operate in producing the same patho- logical results, and how difficult it is to apportion to these causes their relative share in the combined effects. But, apart altogether from the unwholesome influences attach- ing to particular employments, the one great fact which stands forth with special prominence throughout the whole of Dr Greenhow's inquiry (see also Fourth Report to Privy Council) is the fatally defective state of the ventilation, alike of cottage, workroom, and of busy factory. The mortality from lung-disease amongst male and female operatives was found to be from three to six AND THEIR EFFECTS ON PUBLIC HEALTH. 85 times as great as in other districts in England ; and in a very large proportion of cases the want of ventilation in dwelling-places, as well as work-places, prevailed to such an extent, that tubercular and scrofulous diseases must have resulted abundantly from this cause alone. The medical officer of the Privy Council, in comment- ing on this inquiry, remarks " One must remember that, in most cases, either the artisan's ill-ventilated work- place is also his ill-ventilated dwelling-place, or else the dwelling-place to which he goes for his rest is as ill- ventilated as the work-place which he leaves ; that during a great part of the year the work-place has artificial light in it, in many cases gaslight for some hours of the day, and in some cases has its atmosphere vitiated by other products of combustion ; that in factories during winter the commonly adopted method of warming is one which in itself makes the air unpleasant, if not hurtful for breath- ing ; and that in many branches of industry good ventila- tion is essential as a safeguard against evils which are special to the employment essential for the removal of injurious dust, or for the abatement of an oppressive temperature." In all these industrial employments it thus appears that the sick-rate and death-rate could both be very materially lessened by promoting ventilation, and by in- troducing some suitable appliances calculated to protect the workmen from the inhalation of fine dust or noxious fumes. But it was found that the workmen themselves often objected to any innovation which appeared to them to interfere with their more immediate comfort; and not a few of them were under the impression that the introduc- tion of any measures tending to prolong life would be fol- lowed by such an overstocking of the labour market that the difficulties of procuring a living would be greatly increased. That such short-sightedness will continue to 86 AIR: ITS IMPURITIES, exist amongst certain numbers of the artisan class is only what may be expected. Disease sets in so insidiously and progresses so slowly, the stock of health to start with seems so ample, and the individual prospect of death so remote, that sanitary rights are neglected and the wrongs quietly endured. No doubt, these wide-spread evils have been greatly mitigated of late years under the provisions of the Factory and Workshops Acts, but complaints are still made by inspectors that the workmen continue to be very careless about ventilation, and that they have a great aversion to using respirators, even when they know that their use is a safeguard against disease. In Germany the whole of this subject has been very carefully studied by Dr. Hirt, to whose elaborate work, Die Krarikheiten der Arbeiter, I would refer all who are desirous of making themselves fully acquainted with in- jurious trades and the diseases which they severally induce, or are liable to induce, in those employed at them. With respect to the effects of trade-nuisances on the general health of the community, a very important inquiry has recently been conducted by Dr. Ballard in behalf of the Local Government Board, which is of special interest to sanitary authorities and their officers throughout the country. Dr. Ballard's reports were published in the Sup- plements to the Local Government Board Eeports for 1876, 1877, and 1878, and certainly rank as the most valuable and exhaustive contributions which have hitherto appeared on the subject. The trades embraced in the inquiry in- cluded (1), the keeping of animals; (2), the slaughter- ing of animals ; (3), branches of industry in which animal substances are principally dealt with ; (4), trades in which vegetable matters are principally dealt with ; (5), trades in which mineral substances are principally dealt with ; and (6), trades in which matters of mixed origin are dealt with. According to Dr. Ballard, the most offensive effluvia AND THEIR EFFECTS ON PUBLIC HEALTH. 87 are those given off from trade processes, in which the materials used consist of animal substances such as gut scraping, manure manufacturing, and the melting of some kinds of fat. The industries which deal with vegetable substances, though often very offensive, do not appear to give rise to effluvia which may be designated disgusting, and are therefore not so liable to be injurious ; while those which treat mineral substances are chiefly offensive owing to the irritant gases and other effluvia which are given off. As might be expected, great difficulty was ex- perienced in ascertaining, with any approach to precision, in what respect, and to what extent, these effluvia are injurious to health ; but as regards all of them, it has to be noted that in records of proceedings of courts of law, and as the result of Dr. Ballard's inquiries, the particular group of symptoms generally complained of consisted of " loss of appetite, nausea, sometimes actual vomiting, some- times diarrhoea, headache, giddiness, faintness, and a gene- ral sense of depression and malaise!' Concerning effects of a more definite nature, Dr. Ballard points out that while trade effluvia generally contribute their quota of conditions which render the air of manufacturing 'towns comparatively insalubrious, there are certain effluvia of septic origin connected with businesses of a specially filthy nature, which are undoubtedly unwholesome, and give rise to filth diseases of various kinds. Other trades, again, in which matters are dealt with which are liable to be in- fected with specific contagia, cannot fail to be dangerous to persons exposed to such influence ; while, as regards trades which give off effluvia consisting of definite chemi- cal compounds, they are, as a rule, only irritating or injurious in proportion to their degree of concentration. It is often suggested by manufacturers, that because certain effluvia given off by chemical works are in common use as disinfecting agents, they must actually be beneficial to 88 THE EFFECTS OF IMPURE AIR ON PUBLIC HEALTH. public health ; but, as Dr. Ballard points out, this argu- ment is altogether fallacious, inasmuch as such agents are virtually inoperative, unless applied in a degree of con- centration far greater than the diluted effluvia often complained of outside the works. In other respects, Dr. Ballard's reports are especially valuable, because they point out in detail not only the trades or trade processes which are most complained of as offensive, but they explain the methods in use, or which may be devised, for preventing or minimising the nuisances arising from them. This part of the subject, however, will be more fully treated in Chap. XVI. VENTILATION AND WARMING. 89 CHAPTEE IV. VENTILATION AND WARMING. ' THESE two subjects may be conveniently treated under the following sections : I. The Amount of Fresh Air required. II. The Necessary Amount of Cubic Space. III. Natural Ventilation. IV. Artificial Ventilation and Warming. SECTION I. THE AMOUNT OF FRESH AIR REQUIRED. As the air contained in an inhabited room cannot, under the most favourable circumstances, be maintained in as pure a condition as the external air, the object of ventilation is to reduce the impurities of respiration to such an extent that continued inhalation of them will not be detrimental to health. While this can only be effected by a constant supply of fresh air, it is evident that the quantity required will very much depend on the amount of impurities which may be allowed to accumulate in respired air without proving injurious. The first point, therefore, which has to be determined is the limit of maximum impurity consistent with the maintenance of perfect health. It has already been shown that the amount of carbonic acid in air vitiated by respiration is a tolerably reliable index to the other impurities ; and Ijence the question resolves itself into this, What amount 90 VENTILATION AND WARMING. of carbonic acid shall be accepted as the standard of per- missible maximum impurity ? After numerous experi- ments, and a most extended inquiry, Dr. Parkes has given it as his opinion that, allowing *4 volume as the average amount of carbonic acid in 1000 volumes of air, this standard ought not to exceed '6 per 1000 volumes; be- cause, when this ratio is exceeded, the organic impurities, as a rule, become perceptible to the senses. With a ratio of *8, *9, or *L per 1000 volumes, the air smells stuffy and close, and beyond this it becomes foul and offensive. (Practical Hygiene.) Perhaps there is no class of buildings which present better opportunities for arriving at an approximate and practical solution of this problem than prisons ; and it may prove of some service if I record briefly the results of some experiments which some few years ago I had a share in conducting, and which are strongly corroborative of Dr. Parkes' views. In one of the English convict prisons one-half the prisoners are kept in separate con- finement, except when at exercise ; the other half are confined in their cells only during the night and when at meals. The cubic space and ventilating arrangements in the part of the prison occupied by the former were such that the average ratio of carbonic acid, after a series of observations made at different hours of the night, was found to be '720 per 1000 volumes; while in the part of the prison occupied by the latter the cubic space was much smaller, and the average amount of carbonic acid was as high as TO 44 per 1000 volumes. The same number of observations were made in both parts of the prison at the same hours during the night-time, so that a strictly fair comparison could be drawn. Now, a careful inspection of the two classes of prisoners resulted in showing that whereas the former were well nourished and heal thy -looking, the latter presented a somewhat less VENTILATION AND WARMING. 91 robust and more pallid appearance ; and after eliminating every source of error, this difference in appearance could only be accounted for by the difference in the amount of impurities contained in the respired air of both parts of the prison. I have had many other opportunities of examining into this point, and would say, in general, that when the carbonic acid does not exceed '8 per 1000 volumes, no tangible injurious effects upon the health can be detected ; but when it reaches 1 per 1000 volumes, the cumulative effects manifest themselves in producing a pallid dyspeptic appearance, and make themselves felt, in numerous in- stances, in general malaise of a morning, slightly coated tongue, nasty taste in the mouth, and headache. The desirability of adopting Dr. Parkes' estimate as the standard of maximum impurity is also borne out by the observations and experiments of such eminent autho- rities as Professor Pettenkofer of Munich, Dr. Angus Smith, and Dr. de Chaumont. " We all avoid," says Dr. Smith, " an atmosphere containing '1 per cent of carbonic acid in crowded rooms ; and the experience of civilised men is, that it is not ouly odious but unwholesome. When people speak of good ventilation, they mean, with- out knowing it, air with less than '07 percent of carbonic acid. We must not conclude that because the quantity of carbonic acid is small, the effect is small ; the conclu- sion is rather that minute changes in the amount of this gas are indications of occurrences of the highest import- ance." (Air and Rain.) Assuming, then, that '6 carbonic acid per 1000 volumes is accepted as the standard of maximum im- purity, the next question comes to be How much fresh air must be supplied per head per hour, in order that the respired air should not contain impurities in excess of this standard ? It has already been stated, in the previous 92 VENTILATION AND WAKMING. chapter, that an adult man exhales on the average '6 cubic foot of carbonic acid per hour, and taking the initial car- bonic acid contained in the atmosphere at the normal ratio of '4 per 1000 volumes, the quantity of fresh air which should be supplied is found by calculation to amount to 3000 cubic feet per head per hour, in all cases in which the diffusion of the contained air is uniform. Of course, if a standard not so pure is fixed upon, the amount of fresh air required would be proportionately less. Thus, supposing the limit of maximum impurity to be *7 car- bonic acid per 1000 volumes, the amount required would be 2000 cubic feet; if '8, 1500 cubic feet; and '9, it would be 1200 cubic feet per head per hour. It is evident also that women and children would require a smaller supply than men, because they do not vitiate the air so rapidly. The results obtained by actual experiment accord so closely with those which have been deduced from mathe- matical calculation that some of them may be fitly quoted here. The following are given by Dr. de Chaumont (Edin. Med. Journal, 1867) as selections from a series of observations made at Aldershot camp : In a room con- taining 18 men, with a supply of 1200 cubic feet of fresh air per head per hour, the carbonic acid was found to be '855 per 1000 volumes; in another containing 13 men, with a supply of about 1700 cubic feet, it was '759 per 1000 volumes ; and in a third, containing 2 2 men, and with a supply of about 765 cubic feet per head per hour, it amounted to 1*2 per 1000 volumes. All these observations were made at the same hour (5 A.M.), and in barrack -rooms ventilated on the plan proposed by the Barrack Commissioners in 1861, which provided that at least 1200 cubic feet of fresh air should be delivered per head per hour. But there are other circumstances in which it is VENTILATION AND WARMING. 93 necessary to augment the delivery of fresh air in order to maintain the standard of purity. When lights are used, for example, and the products of combustion are allowed to pass into a room, a large supply is required to keep the contained air sufficiently diluted. Thus it is found that 1 cubic foot of coal gas destroys the oxygen of 8 cubic feet of air in combustion, and produces about 2 cubic feet of carbonic acid, besides other impurities. As a common gas-burner burns about 3 cubic feet of gas per hour, the importance of having these deleterious products of combustion carried off by special channels will be readily admitted. It is evident also that the sick require a larger supply of fresh air than the healthy, for it has been found that when as much as 3500 to 3700 cubic feet have been delivered per patient per hour, hospital wards have not been free from offensive smelL Indeed, no greater proof can be afforded of the value of pure air than the excellent results' obtained in surgical cases in times of war, and in medical cases when epidemics are raging, by exposing patients as much as possible to the external air. SECTION II. CUBIC SPACE. This should be large enough to permit the passage of 3000 cubic feet of air per head per hour, without pro- ducing perceptible draughts. If the cubic space per head is small, the renewal of air will necessarily be much more frequent than when it is large. Thus, with a space of 100 cubic feet, the contained air must be renewed thirty times per hour, in order that the standard amount be sup- plied ; whereas, with one of 1000 cubic feet, only three renewals of air would be required. What, then, is the minimum amount of cubic space through which the stand- ard amount of fresh air can be passed without perceptible 94 VENTILATION AND WARMING. movement ? Professor Pettenkofer has answered this question experimentally, and has found that by means of artificial ventilation, and with the aid of the best mechani- cal contrivances, the air in a chamber of 424 cubic feet can be renewed six times per hour without creating any appreciable air-currents. No doubt, therefore, such a space as this, or one somewhat smaller, can be efficiently ven- tilated, provided that perfect artificial means be employed, and the air warmed, but with natural ventilation this becomes impossible. Indeed, a change of air three or four times per hour is all that can be borne in this country without discomfort, and this would require an initial air- space of 750 to 1000 cubic feet. Practically speaking, the difficulties of ventilating small spaces efficiently are due not so much to the movement of the contained air as to the relative position of the inlets, these being of neces- sity so near the person that the draughts which are pro- duced become disagreeable or injurious. This is well exemplified in the case of prisons. In hard-labour prisons, where convicts are confined in their cells only during the hours of rest, the cell-space seldom exceeds 200 cubic feet. The consequence is that in cold or inclement weather these draughts become so unpleasant that many of the prisoners block up the inlets as effectually as they can, and of course obstruct the ventilation to a serious extent. So far as my experience goes, it is difficult, even with the aid of a well-devised plan of ventilation, to sup- ply the necessary amount of fresh air per head per hour without creating perceptible draughts occasionally, if the space be less than 600 cubic feet. I have further satis- fied myself that with the same artificial appliances and arrangements, the air contained in small occupied spaces becomes much more impure than in large spaces. For example, in the experiments already alluded to in the last chapter, the cell-space in one-half the prison was 210 VENTILATION AND WARMING. 95 cubic feet, in the other half it was 614. The same means for extracting the foul air through flues leading from every cell to a foul-air extraction shaft, in which a fur- nace was kept burning to produce a constant draught, were common to both parts of the building. Moreover, the fresh-air inlets were more amply provided for in the small than in the large cells, and yet the average amount of carbonic acid, after a series of observations, was found to be 1*044 per 1000 volumes in the former, and only 720 in the latter. With a small cubic space it is impossible to obtain uniform diffusion of the contained air, if a large amount of fresh air is supplied, because between inlet and outlet a 'direct current is established, and a considerable quantity of air passes right through without being utilised. Again, it is evident that if the ventilation is impeded or becomes arrested, impurities will collect with far greater rapidity in a small than in a large space, and this of itself is a great argument in favour of the adoption of an ample cubic space as a basis. Dr. de Chaumont, in his remarks on this point, writes : " Let us suppose two occupied spaces, one of 500 and the other 1000 feet, ventilated so that the ratio of carbonic acid is '06 per cent, and that from some cause or other the ventilation is arrested in both, the condition will then be as follows : "1000 feet "Ratio of impurity. 'After one hour . -12 per cent, two hours . '18 three ,, . '24 four ,, . -30 six -42 seven ,, 48 "500 feet "Ratio of impurity. After one hour . *18 per cent, two hours . '30 three ,, . '42 four . -54 six 78 seven 90 With ordinary means of ventilation (artificial excluded) both Dr. Paikes and Dr. de Chaumont have contended that the cubic space for a healthy adult ought at least to 96 VENTILATION AND WARMING. be 1000 feet. It is true this is very much in excess of what is generally obtained. In the crowded dwellings of the poorer classes it seldom exceeds 200 to 250 cubic feet ; but then the disastrous effects declare themselves but too clearly in the increased rate of mortality. In metropolitan lodging-houses the allowance per head is as low as 240 cubic feet; and in the Dublin registered lodging-houses it is 300. The Barrack Commissioners, on the other hand, recommended a minimum space of 6 cubic feet for soldiers, insisting at the same time that the air should be renewed at least twice every hour. " The only safe principle," they said, " in dealing with the sub- ject is to have a large margin for contingencies ; and the question really is, not whether 600 cubic feet per man be too much, but whether 600 cubic feet per man be enough for all the purposes of warming, ventilation, and comfort." Experiments that have since been made, and particularly those conducted by Dr. de Chaumont, prove most incontestibly that even this comparatively large allowance is inadequate for these purposes ; but it was as much as could be obtained at the time, without putting the country to enormous expense. The Commissioners themselves observe : " It has been said that the question of cubic space is simply a question of ventilation, but it is rather a question as to the possibility of ventilation. The more beds or encumbrances you have in a room, with a limited cubic space, the more obstruction you have to ventilation-; the fewer the beds, the more easy is it to ventilate the rooms. There are fewer nooks and corners, fewer surfaces opposed to the movement of the air, and less stagnation. We have been in rooms, both in barracks and hospitals, in which the atmosphere was positively offensive with the doors and windows open." For further remarks on cubic space in hospitals, see Chapter on Hospitals. VENTILATION AND WARMING. 97 Iii summing up this part of the subject, the following may be accepted as the standard conditions necessary for the requirements of perfect health : 1. That the limit of maximum impurity of air vitiated by respiration ought not to exceed '6 carbonic acid per 1000 volumes. 2. That to ensure the maintenance of this standard under ordinary circumstances, 3000 cubic feet of pure air must be supplied per head per hour. 3. That for this purpose, and with ordinary means of ventilation, a space of at least 1000 cubic feet should be allowed per head in buildings permanently occupied. It may be objected that these conditions aim at too high a standard, and that in general they are seldom met with ; but it must be remembered, as Dr. de Chaumont has so well pointed out, that they are based on a firm foundation of facts, and that, though it may not be pos- sible to prove in all cases that bad effects result from a neglect of them, it does not follow that such bad effects may not have been produced. In a country like this, with a climate so variable, the cubic space allowance is a most important element in any scheme of ventilation. It should be ample enough to permit of a sufficient supply of fresh air without creating injurious draughts, and yet not too large to interfere with the maintenance of a sufficient and equable temperature during cold weather. "Where artificial ventilation is provided, and when the fresh air can be heated before entering, it may be as low as 400 cubic feet, but even then the ventilating arrange- ments must be much more perfect than they usually are. In the case of healthy adults, such as soldiers and prisoners, the standard allowance may also be consider- ably lessened, if care be taken that the free entrance of fresh air at all hours and in sufficient quantity shall not be interfered with. Unfortunately the question of cubic H 98 VENTILATION AND WARMING. space is a question of large outlay, and hence the desire to economise tends to curtail the minimum not within safe limits, but within limits that will not be attended with glaring injurious effects. In advocating these conditions, however, it is but right to state that the numerous experiments and weighty opinions of Dr. Angus Smith are somewhat at variance with them. In the first place, Dr. Smith's experiments only give *4 cubic feet of carbonic acid per hour, which would reduce the requisite amount of fresh air supply per hour to 2000 cubic feet; and, in the second place, Dr. Smith maintains that uniform diffusion of the contained air is the exception and not the rule, and in fact that it does not occur at all. With regard to the first of these points, the discrepancy between Dr. Smith's results and those of other physiologists may be reconciled on the ground that his trials were admittedly not made on large men ; but with regard to the second, there still exists considerable divergence of opinion. If by uniform diffu- sion throughout an occupied space is meant the exact uniformity of the chemical composition of the air in every part, then it must be conceded that Dr. Smith is strictly correct ; for so long as fresh air is entering and foul air issuing from a room, there will not only be a difference between the composition of the air in the immediate proximity of the inlets and outlets, but there will also be a difference in various parts caused by the currents, how- ever imperceptible these may be. In small occupied spaces, such as prison cells, provided with adequate means for artificial ventilation, the amount of fresh air required to keep the carbonic acid from exceeding *6 per 1000 volumes must obviously be much less than the amount required per head in a large room, because uniform diffu- sion is impossible, there being a constant movement of the air from inlet towards outlet. But in a large space VENTILATION AND WAKMING. . 99 the case is different, even though the cubic space per head be not greater than that of the prison cell. The entering currents and the currents produced by inequalities of temperature are, in this instance, much more numerous, and produce a much greater mixing of the air, while the impurities given off by respiration have greater scope to be affected by the laws of gaseous diffusion. For all practical purposes, therefore, the condition of uniform diffu- sion, as applying to a room occupied by several persons, may be accepted as sufficiently accurate; and this being so, the standard amount of fresh air to be delivered per head per hour should, as already stated, be 3000 cubic feet. Indeed, the whole of the controversy between Dr. Angus Smith, on the one hand, and Drs. Parkes and de Chaumont on the other, regarding this point, seems to be based on a misunderstanding ; each party estimated the requirements of ventilation for a single individual, but under different conditions the former taking it for granted that the space is occupied by one, the latter that it is occupied by several. SECTION III. NATURAL VENTILATION. Xatural ventilation is earned on by the agency of natural forces, such as gaseous diffusion and movements of air produced by inequalities of temperature. 1. Diffusion. The force of gaseous diffusion, upon which the uniform constitution of the atmosphere itself depends, is manifestly inadequate as a ventilating power. It operates chiefly in producing, as has been already stated, a tolerably equal distribution of the gaseous products of respiration and combustion throughout the air contained in a room, but aids only to a very slight extent the removal of these impurities from the room, while it is altogether inoperative as regards the removal of organic impurities. 100 VENTILATION AND WARMING. 2. Movements of Air produced ly Inequalities of Temperature. As common air is subject, like other gases, to the laws of gaseous expansion, it undergoes a certain increase or diminution in bulk, according as it is heated or cooled. Warm air is, therefore, lighter than cold air, and hence a constant interchange goes on through every available opening, whenever there is any difference be- tween the outside and inside temperature. The contained air, on being heated, expands, a portion of it escapes, and the colder outside air rushes in to establish the equilibrium. In this way a constant stream of fresh air may be made to enter a room by simply keeping the inside temperature higher than the outside. But in addition to the slighter currents, the movements of the external air, or winds, greatly assist ventilation by their perflating or aspirating action. Perflation is best exemplified in the cross-venti- lation which takes place through opposite windows when opened. This is by far the readiest means which can be adopted for removing speedily and effectually aerial im- purities from a room, but it cannot always be depended on, on account of the uncertainty of the rate of movement ; for if the air be stagnant, there can be little or no perfla- tion, while, on the other hand, if the rapidity of movement is great, perflation becomes insupportable in consequence of the draughts produced. A current of cold air moving at the rate of five or six feet per second becomes unbear- able. In spite of this objection, however, cross -ventilation should always be provided for whenever it is practicable, and especially in large rooms, such as hospital wards. The aspirating action of the wind produces up-currents through chimneys and air-shafts, by creating a partial vacuum in them, which is constantly being filled by the column of air from beneath. The mechanical arrange- ments which have been proposed or adopted to facilitate the action of these natural ventilating powers are so VENTILATION AND WARMING. 101 numerous and varied, that only a brief mention of the more important of them can be given. To utilise the perfating force of the wind, opposite windows should be made to open from the top and bottom, and to obviate the unpleasantness arising from draughts, some such arrange- ments as the following have been recommended : (1.) By having the window so constructed that the top^slopesjnward when it is opened, so that the entering I ' current of air impinges against the ceiling. If the win- dow is large, as in churches or schools, only a section of the upper part may be made to open in this way. (2.) By substituting a glass louvre for the top centre pane. (3.) By having some of the panes doubled ; the outer with an open space at the lower edges ; the inner with an open space of the same size at their upper edges. The air on entering is thus made to pass upwards between the panes. ll (4.) By having some of the panes made of perforated glass, as in Pott's plan. (5.) By raising the lower sash of the window two or three inches and filling in the opening under the bottom rail with a piece of wood as proposed by Mr. P. H. Bird. This leaves a corresponding space between the meeting rails in the middle of the window through which the enter- ing current of fresh air is directed towards the ceiling. (6.) By having a part of a pane to open or shut at will by a spring arrangement, as in Boyle's ventilator. (*7.) By fixing a fine wire screen to the top of the window, which unfolds when the window is pulled down, and folds up when the window is shut. As the fine meshes of the screen are apt to become clogged up with dust, this plan is objectionable, except when the windows are of low elevation as in attic rooms. Other outlets and inlets may be provided by inserting 102 VENTILATION AND WARMING. perforated bricks in the walls near the ceiling. One of the best inlets is the Sheringham valve, which closes at will by a balanced weight. It slopes inwards and upwards when open, so that the entering current of air, which first passes through a perforated brick or grating, is directed towards the ceiling. Currall's patent ventilators, supplied by Tonks and Sons, Birmingham, are easily applied, and appear to work 'very well. The inlet is made suitable for doors, windows, and walls, and is so arranged as to obviate disagreeable draughts, while the outlet may be inserted in the chimney- breast or an outer wall. Ellison's conical bricks, which are pierced with conical holes, are so constructed as to admit outer air without creating perceptible draught. In some cases cross- ventilation can be tolerably well maintained, independently of opposite windows, by means of transverse ventilating boxes or tubes, situated at regular distances, and in close proximity to the ceiling. These boxes or tubes extend from wall to wall, and communicate with the external air at either end by air-bricks. The sides are made of perforated zinc, and there is a diaphragm in the centre of each, to prevent the wind from blowing right through. According to the direction of the wind, one-half the tube becomes an inlet for fresh air, which falls gently into the room through the perforated zinc, while the other half becomes an outlet for the vitiated air. This plan does very well for large hospital wards having an internal corridor running along one side. Inner rooms can also be supplied with a certain amount of cross-ventilation in the same way. Another plan which has been very much lauded within the past few years is that which is associated with the name of Mr. Tobin of Leeds. It consists in intro- ducing fresh air by means of vertical tubes carried for a VENTILATION AND WARMING. 103 rertain distance up the walls of the room, so as to obviate any discomfort arising from down-draught. In rooms or class-rooms with windows only on one side, this is a very convenient method of improving the ventilation. Another method of ventilating by pipes, introduced by Messrs. Shillito and Shorland of Manchester, has also been found to work very well. The aspirating power of the wind is frequently utilised by placing cowls on the tops of air-flues or chimneys. It' not made to rotate according to the direction of the wind by means of vanes, they should be so constructed as to prevent the entrance of rain. Among cowls which have received favourable notice may be mentioned the various cowls patented by Banner, Bond, Boyle, Buchan, Ellison, Scott, Dunn and Co., and Wawn and Wilcox. According to some recent experiments conducted by a Committee of the Sanitary Institute at Kew Gardens, the great majority of cowls tested showed no superiority in aspirating power over the simple open tube. Louvres are sometimes used instead of cowls, but, unless specially constructed, they are apt to let in the rain and permit down-draughts. In several plans of natural ventilation the perflating and aspirating powers of the wind are both taken advan- tage of. Thus, in Mr. Sylvester's plan, which was in use fifty years ago, a large cowl surmounted the fresh air entrance shaft, and by means of a vane was always made to face the wind. The shaft itself was erected at a con- venient distance from the building to be ventilated, and of a height varying according to circumstances. In this way the air, so to speak, was blown into the cowl and down the entrance-shaft into a chamber beneath the base- ment floor, where it could be heated if necessary. It then ascended by tubes leading to the different parts of the building, and finally passed out through a shaft or 104 VENTILATION AND WARMING. shafts projecting above the roof, and also fitted with cowls turning away from the wind, so as to act as aspirators. By a suitable arrangement of shafts and cowls, this mode of natural ventilation can be made to do excellent service in ships, and in buildings so constructed or situ- ated that other ventilating means will not suffice. It was on this principle that Dr. Arnott ventilated the Field Lane Eagged School so successfully. The entrance and exit tubes were both fitted with cowls, the one set turning away from the wind, the other facing the wind. The latter also were of a higher elevation than the former, in order to increase their extractive power. A system of natural ventilation, well suited for large rooms, and which has been highly spoken of by Mr. Eobson, architect to the London School Board, is that devised by Mr. Potts. It consists of a hollow metal cornice running continuously round the room, and divided longitudinally throughout its whole length into two separate channels, by a plate attached to the lower one. The fresh air is admitted through openings in the wall into the lower channel, and falls imperceptibly into the room through numerous perforations. The upper channel communicates either with the smoke-flue or other air- shaft, and receives the vitiated air through a series of small openings similar to those of the lower channel. As the fresh air, being colder, descends by its own gravity, and the vitiated air, being warmer, rises to the highest point, there is no doubt that the principles of the system are correct. Mr. Eobson strongly recommends it for facility of application to buildings originally erected without proper provision for ventilation, for sightliness, economy of first cost, and self-acting properties. Another plan, which has been found to work well in schools, has been proposed by Mr. H. Yarley. A per- orated zinc tube, communicating with the external air VENTILATION AND WARMING. 105 passes along the cornice of three sides of the room, while on the fourth side another perforated tube is connected with the chimney, which acts as the extraction-shaft. The plan proposed by Mr. M'Kinnell, though it belongs to the same category, is less widely applicable than either of these two, because it is only suited for one- storied buildings or upper rooms. It consists of two hollow cylinders, one within the other, and of such relative calibre that the transverse area between the tubes is equal to the sectional area of the inner tube. The inner tube is of slightly higher elevation than the outer, and acts as the outlet. The fresh air enters between the tubes, and is thrown up towards the ceiling by means of a horizontal flange surrounding the lower margin of the inner tube. Both tubes should be situated in the centre of the ceiling or roof. For ventilating workshops or factories, another plan has been advocated, which appears to possess some special merits beyond those of mere novelty. -It pro- poses that the ceiling of every workshop should be formed of zinc or oiled paper pierced by numerous small holes. Above this perforated ceiling, and between it and the roof, or between it and the next floor above, there should be a free space or air-chamber open to the atmo- sphere on all sides. This plan, while it would not interfere with ventilation by open windows nor with ordinary methods of warming, would give free play to the different modes of natural ventilation, and is intended to supply, as nearly as possible, the conditions of living in the open air, summer and winter, without exposure to extremes of weather. 106 VENTILATION AND WAKMING. SECTION IV. AETIFICIAL VENTILATION AND WARMING. It will be convenient to consider these two subjects conjointly. Artificial ventilation is carried on either by forcing the air into and through a room (propulsion), or by draw- ing the air out of a room (extraction). These two methods are also spoken of as the plenum and vacuum systems of ventilation. Although it may appear to be an easy matter to ventilate a room without any regard to temperature, or to warm it without providing for a due supply of fresh air, it becomes a problem of very considerable difficulty to ensure, in all cases, that both the ventilation and warm- ing shall be efficient and satisfactory. This difficulty depends in a great measure on the fact that the means employed in ventilating necessarily dissipate and carry off a certain quantity of the heat which should be utilised for warming purposes. In this country artificial ventilation and warming are usually provided for by open fire-places. The heat is obtained by radiation from the incandescent fire, and by radiation and reflection from the different parts of the grate, while ventilation is carried on by the constant current of heated air rushing up the chimney. Even when there is no fire, the chimney acts as a very efficient ventilating shaft. When doors and windows are closed and a fire kept burning, the fresh air enters the room through every chink and opening, provided there are no special inlets. Hence it follows that the more closely doors and win- dows are made to fit, so much greater are the obstacles to the entrance of fresh air. When this is the case, the VENTILATION AND WARMIXC;. 107 fire feeds itself by establishing a double current in the chimney, the downward current entering the room in puffs, and carrying with it clouds of smoke. Generally, however, doors and windows are not made to fit so closely that a sufficient amount of air for feeding the fire cannot enter, and under ordinary circumstances the supply and circulation are somewhat as follows : The greater portion of the fresh air enters beneath the door, and is drawn along the floor towards the fire-place. It is warmed to a certain extent during its course by the radiating heat of the fire, and when it approaches the fire-place, part of it rushes up the chimney along with the smoke, while the other part ascends towards the ceiling, and after ascending- passes along the ceiling towards the opposite end of the room. During its progress it becomes cooled, and there- fore descends to be again drawn towards the fire-place with a fresh supply from beneath the door and through the chinks of the window-frames, if they are not air-tight. As the air which thus enters is usually cold air, it is evident that the room is insufficiently or unequally warmed and badly ventilated. At the end of the room opposite the fire-place the temperature is below the average, and the cold current near the floor chills the feet. Moreover, the air is not properly diffused, so that although a sufficient supply may actually be entering, impurities are apt to accumulate in the centre and upper parts of the room. The position of the fire-place is likewise a matter of considerable importance. The practice followed by most builders is to place fire-places in external walls, by which means a large amount of heat is wasted. If, on the other hand, they are grouped in the centre of the house, more heat is utilised, and greater equability of the inside temperature is maintained. With ordinary fire-places it is found that nearly 108 VENTILATION AND WARMING. seven-eighths of the heat generated passes up the chim- ney, along with a quantity of air varying from 6000 to 20,000 cubic feet per hour. While, therefore, a single chimney will on the average act as an efficient ventilating shaft for a room containing from three to six or more persons, it is quite clear that by far the greatest portion of the fuel is wasted as a warming agent. The structure of the fire-place thus becomes a matter of special import- ance, because not only may the fuel be economised to a considerable extent, but by certain mechanical arrange- Fig. 1.-- Elevation, showing air ancV smoke flues. Fig. 2. Section of Grate. Fig. 3. Section of a room showing air-duct and flues. Fig. 4. -Plan of grate and air- chamber. (After GALTON.) ments an equable temperature may be maintained and the air warmed before it enters the room. Of the fire-places adapted to meet these requirements, one of the best, although it has now many rivals, is the VENTILATION AND WAKMIXd. 109 stove devised by Captain Douglas Galton (see Figs. 1, 2, 3, and 4). It provides for an air-chamber at the back, in which the fresh air is heated before it enters the room. If the fire-place be built in an external wall, the inlet for fresh air may be situated immediately behind, but if in an inner wall, a channel communicating with the external air by perforated bricks or gratings, and passing beneath the flooring or behind the skirting, must be laid, On the back of the stove broad iron flanges are cast, so as to present as large a heating surface as possible. These project backwards into the chamber, and this heating- surface is further supplemented by the smoke flue, also of iron, which passes through the chamber, and is made continuous with the chimney. The fresh air heated in this manner enters the room by a louvred opening situ- ated between the fire-place and ceiling, or by two such openings, one at either side of the chimney-breast. The grate itself is so constructed that the greatest amount of obtainable reflected heat is given off, and a more perfect combustion of the smoke effected than with an ordinary grate. The stoves are of different designs and sizes, to suit existing chimney-openings and different sized rooms. They have the same cheerful aspect as the ordinary grate, and produce the same degree of warmth in a room with a third of the quantity of fuel ; besides, the temperature of the room is much more equable, and unpleasant draughts of cold air are avoided. In Boyle's ventilating grates, which are perhaps more ornamental, the heated air enters the room through a transverse fenestrated opening extend- ing along the top of the grate. In Shorland's patent Manchester grate, which has been highly spoken of, the warmed outside air is made to enter the room through the shelf of the chimney-piece, and by means of special flues it can be conveyed to bedrooms above. Kitchen stoves have also been constructed on the same principle, 1 1 \T\ I'll \TION \\M \V MIMINC. and stoves suited for the centre of halls or wards. The Smoke-Hue of llie latter is made to pass out under I he Mooring, and inside the fresh-air entrance ehannel, thus supplying a larger heat in;;- area for the entering air. The terra-cotta stoves in Herbert Hospital are of this descrip- tion. But SO many radiating grates have lately been patented that it would be impossible to gi\e any selected list here. Indeed, with regard to grates, kitcheners, and stoves of all kinds which have been specially commended, the reader is referred to the list of the awards given at the recent Smoke Abatement Inhibition held at South Kensington. (See &i nit tin/ ./iVren/, August 15, 1S8L'.) At this exhibition numerous grates were shown, which. in addition to (heir warming properties, were specially devised to economise fuel and consume their own smoke. Tlu 4 vast majority of grates at present in use are con- structed on wrong principles by allowing the cold air to rush through the centre of the tire, thus causing vapid consumption of the fuel, and sending the warmth along with the half-bnvued gases up the chimney. In order to economise fuel it is necessaiy to cut off this stream of cold air which passes through the bottom of the grate, an arrangement which is carried out in all grates made with solid tire-brick bottoms, after the pattern of the Parson's, Abbotsford, or Kyrle grates. lut . as "Mr. Pridgin Teale has so clearly pointed out in a small brochure on economy of coal, the same results can be obtained by closing up the open chamber under the grate by means of a close-tilting shield or door, which can be made by any blacksmith or ironmonger. Indeed, according to Mr. Teale's experiments, grates provided with these shields, or " economisevs " as he calls them, answer better than those with solid tire-brick bottoms, and he gives some excellent rules regarding the construction or alteration of tire-places, which arc of such general application that they may be Tir.ATIo.N AND WAUM! 1 1 1 fitly (piotcd liens:- "1. Use as much lire-hriek MMJI litllc Iron M possible. "2. Tin-, bark and sides of the lire- plare sli(.uloiiomic Association. l''or wai'n and venlilalin^ bedrooms, 1 he (liermie venl ilalnr d-\ i by Mr. l.au^oii Tail ol' I'.ii nun-ham may be luenl imn-d a .1 cheap ;ind ei'jed i\c arrangement The "Tea! ohjertiull (i, HiailV of the e ) 1 1 1 1 |o| |e } Kind- 'o\C depend- nn (he fart, thai their nver-liealed SUr- dry the air to a very un\\holesoi. !, even \\heii the fiv h air is runveyed by ;i .special entranee ehannel. N umbers of I hem, lm\\ ever, are put up \\ilhout ]>rovidin- any suc-Ii rhaniiel, |Q that tiir air not only hr- eoinr-; dry and he.int, hut r.\r ( .rdin;jly < !<> c and un pica -ant. luap-iialiii" dishes place. | t) n tbc itOVM v\ill Mlifl in reinedyin- tin's evil, 0T painliu;- tin- imn sinia.e \\itli a 112 VENTILATION AND WARMING. solution of silica, as suggested by Dr. Bond; but it is much preferable, and in the long run more economical, to have a good ventilating stove erected in the first instance. For all ventilating stoves it is necessary that the fresh-air channels should be removed from all sources of contamination, such as drains, closets, stables, etc. ; and it is advisable to protect the external openings by per- forated bricks or gratings. The size of the stove, and the sectional area of the air-channel, must of course be regulated by the size of the space which is to be warmed and ventilated. Stove smoke -flues may be either ascending or de- scending, but in the latter case a pilot-stove or rarefier ought to be fixed at the base of the upright chimney which receives the flue, otherwise the draught may prove faulty. Soot doors should be provided at all the bends, wherever practicable. With the ordinary grate the ventilation of a room may be very greatly improved by providing an entrance into the chimney near the ceiling, and to prevent reflux of smoke, the opening should be valved, as in Dr. Arnott's chimney ventilator, or Crossley's noiseless ventilators. One or more openings for the entrance of fresh air could be obtained by inserting perforated bricks or Sheriiigham valves in the outer walls, also near the ceiling, but at a distance from the fire-place, or by adopting one or other of the several contrivances mentioned in the pre- vious section. Indeed the mistake which is common to the great majority of houses consists in providing an outlet, generally the chimney, and neglecting to provide an inlet, whereas the essential principle of ventilating demands that there shall be at least two openings, one of which shall act as an inlet, and the other as an outlet, according to circumstances. Instead of an opening leading directly into the chim- YKXTILATIOX AND WARMING. 113 ney for an outlet, a much better plan is to have a flue ' running alongside the chimney, the entrance to the flue being situated near the ceiling. The hot air in the chim- ney warms the flue, and there is thus a constant upward current established without any risk of reflux of smoke. But this is an arrangement which can only be attended to in the original plan of a building ; it cannot be applied as an improvement afterwards. Some architects recommend that all the rooms in a well-constructed house should be supplied with warm air from the hall and staircase. In Mr. Ritchie's plan the air is heated to about 70 Fahr., and enters the various rooms through longitudinal openings over each door. After being diffused through the rooms, it then passes up the chimneys and through flues reaching from the ceiling to the wall-heads under the roof. Somewhat similar to this is the plan devised some time ago by Drs. Dry sd ale and Hay ward of Liverpool. The fresh air, warmed by a coil of hot-water pipes in the basement, is admitted into a central hall containing the staircase and separate landings, from which it enters the several rooms by suitable openings supplied by valves, and from these again it is conveyed to special outlets in the ceilings, converging to a foul-air chamber under the roof. From this foul-air chamber there is a downcast shaft communicating with the kitchen fire, which is thus made to act as an extraction furnace. With regard to these and other complicated methods of house -ventilation, it has to be pointed out that no system is to be commended which dispenses with the opening of windows occasionally in order to secure thorough perflation. No doubt, it adds greatly to the comfort of a house if the air in the hall is warmed, and it will also add greatly to comfort if the air thus warmed can be introduced into the rooms by suitable openings ; I 114 VENTILATION AND WARMING. but even in winter the windows should be thrown open for a brief period at least every morning, and in summer, window-ventilation should be chiefly depended on, and the entrance-hall, if louvred in the roof, would act as an extraction-shaft. Large and compact buildings, such as hospitals, asylums, and prisons, can be very efficiently warmed and ventilated by a suitable arrangement of steam-coils or hot- water pipes. The fresh air, as it enters through openings properly distributed throughout the building, is warmed by passing over the pipes, while the vitiated air may be extracted by means of other coils of heated pipes situated in extraction-shafts. Another mode of ventilation by extraction, and one which is frequently used in prisons, consists in having a large foul -air extraction shaft or shafts, heated by a furnace at the bottom, and into which foul-air flues, lead- ing from all parts of the building, are conducted. The workmanship in this case requires to be very perfect, so as to prevent any large currents of air reaching the shaft except through the flues. / / By a combination of these two methods viz. heating ) the fresh air before entering by hot -water pipes, and t securing the removal of the vitiated air by flues leading to furnace-shafts the largest buildings can be well warmed and ventilated. If necessary, the hot- water pipes may be made to pass through shallow basins of water, to ensure a sufficiency of moisture in the contained air. As an instance of the successful ventilation of a large hall, which until recently was notorious for its defects in this respect, may here be mentioned the improvements which were carried out in 1882 in the Council Chamber of the Guildhall, London, by Messrs. Boyle and Son, the well-known ventilating engineers. The conditions under which they undertook to remedy the existing defects were VENTILATION AND WARMING. 115 of the most stringent nature, but they were carried out so completely as to meet the approval not only of the committee appointed to enforce them, but of numbers of well-known writers on ventilation, who were invited to test and examine the working of the system, which is, in the main, automatic. Briefly stated, the plan adopted by Messrs. Boyle was as follows : For thejnlet of fresh air, sixteen vertical ventilating shafts, projecting only about three inches from the walls, were placed in various parts of the chamber, and with outlets at different altitudes, so as to admit the fresh air at different heights. These shafts are fitted with patent heaters, which are warmed by means of a gas jet fixed by the side of each shaft and enclosed in a metal casing, so that the tem- perature of the incoming air can be regulated by raising or lowering the gas jets. The heat imparted by each gas jet is carried up inside the shaft to a certain height by a tube, which then crosses it, and is brought down zigzag fashion to a small receptacle at the bottom, which receives the water of condensation, and transmits it, along with the other products of combustion, through a small tube to the outside. By this means a constantly induced current of fresh air can be kept up in all the shafts, what- ever be the temperature of the outside air ; while the vitiated inside air is extracted by shafts springing from various parts of the ceiling through roseate perforations, and converging to patent exhaust cowls on the roof. Almost all large mines are ventilated on this principle of extraction. By means of a furnace at the bottom of the upshaft, the air is drawn down another shaft and made to traverse the various galleries by an arrangement of partitions and double doors. In well- ventilated mines as much as 2000 cubic feet of air per head per hour can be supplied in this way, and in fire-damp mines, 6000. In men-of-war and steam-vessels an iron casing sur- 116 VENTILATION AND WARMING. rounding the bottom of the funnel and upper part of the boilers is utilised as an extraction shaft. When the fires are kept burning, so great is the current which rushes up this shaft, that the air can be drawn through the hatch- ways from all parts of the vessel, and even the hold and timbers ventilated. In theatres, and other buildings of a similar descrip- tion, the chandeliers should always be employed to extract the vitiated air. According to the experiments of General Morin, one cubic foot of gas can be utilised so as to cause the discharge of 1000 cubic feet of air. Apart, therefore, from the great advantages arising from the direct removal of the products of combustion, the aid to ventilation fur- nished by the extractive power of gas-lights merits special attention, for as a common gas-burner will burn nearly 3 feet of gas per hour, its extractive power could thus be utilised to remove nearly 3000 cubic feet of vitiated air during the same period. Where a large flood of light is required, the " sun-burner " acts very efficiently in this way, and for smaller rooms or workshops, the " box-top sun -burner" is found to answer very well. Eickett's new "ventilating globe-light" ought also to be mentioned amongst the latest improvements in this direction. It is so arranged that so soon as the gas is lighted, an upward current is produced in the main tube, and as this becomes heated, the air in the surrounding tube near the ceiling becomes rarefied and set in motion. In this way the heated air in both tubes is carried to a special shaft or to the chimney, thereby securing the removal of the products of combustion, and a steady current outwards of the vitiated air in the room. Tubes of tin or zinc placed over common burners, and communicating with the external air, or leading into the chimney, would answer the same purpose where ornamentation can be dispensed with ; but in either case it is necessary that the room YKNTILATION AND WARMING. 11 7 should be well ventilated, otherwise the extractive force of the fire will most likely occasion a down-draught through the ventilating tubes. Extraction by means of a steam jet, and extraction by a fan or screw, are now generally abandoned on the large scale. What is known as the Archimedean-screw ventilator, however, has been lately recommended for small air-shafts, and has also been applied to large fac- tories, where it may be worked by hand or steam power. In mines, the fan has been made to extract as much as 45,000 cubic feet of air per minute. The system of ventilation by propulsion was first introduced by Dr. Desaguliers in 1734. It is carried on by means of a fan enclosed in a box, which can be worked by hand, horse, water, or steam power. The air enters through an opening in the centre of the box, and is thrown by the revolving fan into a conduit which com- municates by proper channels with the different parts of the building. In France and America the fan is employed in the ventilation of several of the large hospitals, the air being forced into a basement chamber, where it is heated before it enters the wards. This is known as Van Hecke's system. In this country St. George's Hall, Liverpool, may be cited as affording an example of venti- lation by propulsion on the large scale. The air is taken from the basement, and washed by being passed through a thin film of water thrown up by a fountain. It is then passed in cold weather into vessels for the purpose of being warmed, and in which it can be moistened by a steam jet whenever the difference between the dry and wet bulb exceeds 5, and finally, it is propelled along different channels into the hall. In summer, the air in the conduits is cooled by the evaporation of water. Various other methods of propulsion have been tried, such as the bellows arrangement proposed by Dr. Hales, 118 VENTILATION AND WARMING. or the gasometer pump worked by hydraulic pressure planned by Dr. Arnott, but mostly all of them have fallen into disuse. Concerning the relative merits of these two systems of ventilation, viz. extraction and propulsion, the balance of evidence is most decidedly in favour of the former, as regards cost, efficiency, and stability. In either system, natural ventilation plays a most important part, whether it be taken into consideration in the construction of buildings or not; and hence every facility should be afforded for its operation, without at the same time per- mitting its disadvantages to take effect. For dwelling- houses, workhouses, asylums, barracks, and hospitals, there is no doubt that natural ventilation, aided by the ex- tractive power of the heat generated in warming and lighting, is by far the best system. On the other hand, buildings such as prisons, theatres, etc., must be venti- lated by mechanical appliances, and experience has proved that these should provide for ventilation by extraction. General Considerations. With regard to the relative position of inlets and outlets, there seems to be some difference of opinion. Theoretically, the inlets for the fresh air should be situated near the floor, and the outlets near the ceiling : but the question of temperature inter- feres with the practical application of this rule. If the air is not warmed before entering, the inlets should be at least nine or ten feet from the floor, or close to the ceiling, and so constructed that the cold air will impinge against the roof, and fall gently into the room. They should slope upwards to prevent entrance of rain, and should communicate with the external air by means of perforated bricks or gratings so as to divide the entering current and break its force. With vertical tubes such as Tobin's or Shorland's tubes, the inlets need only reach about six feet from the floor. Sliding covers, valves, or rotatory discs VENTILATION AND WARMING. 119 might also be provided, in order that they may be partially or totally closed during rough weather. If the air is warmed before entering, the inlets may be situated, and generally are situated, near the level of the floor. But in either case it is essential that they should be equally distributed throughout the room, to ensure proper diffu- sion, and that the structural arrangements should permit of their being readily cleaned out, because dirt is sure to accumulate. The outlets, as already stated, are best situated in or near the ceiling, not only because air vitiated by respira- tion tends to ascend on account of its lessened density, but because experiment proves that, given the same ex- tractive power and the same size of outlet, a greater volume of air passes up a flue whose orifice is near the ceiling than up one whose orifice is near the floor. Inlets and outlets should not be situated near each other, otherwise the entering air will be extracted without being first diffused throughout the room. Outlet tubes, or foul-air flues, as they are generally called, should be smooth, so as not to impede the current of air by friction, and in systems of ventilation by extrac- tion they should be air-tight. When built in external walls and only plastered, I have frequently satisfied my- self by experiment that the outside air finds its way into the flue and sometimes in such volume that though there may be a good current issuing from the top, scarcely any current can be detected entering it at the bottom. I have also found that when the wind beats strongly against the side of a building, with foul-air flues situated in the outer walls, a current of air may actually be issuing from both orifices at the same time. The experiments of Pettenkofer explain how readily such an occurrence may take place, for he has proved beyond doubt that even under ordinary atmospheric conditions, a very considerable interchange 120 VENTILATION AND WARMING. of gases takes place through common dry-plastered walls, and indeed, as the sick often experience, very perceptible draughts find their way through outer walls when a stiff breeze is blowing. All foul-air flues, therefore, should be as nearly air-tight as possible, and if they were made of metal tubing, or of glazed earthenware, they would not only satisfy this condition, but would serve greatly to lessen the friction, which is such an impediment' to ready extraction through common plastered flues. It is further evident that, when it can be avoided, they should not be situated in external walls, because in cold weather the air becomes cooled as it ascends, and unless the extractive power is very considerable, the increased weight of the column of air by loss of heat will counteract the ex- tractive force. "Where there is no system of artificial extraction, it thus often happens that outlets become inlets, and inlets outlets. Another very important point remains to be con- sidered, namely, the sectional area of the inlets and out- lets. As atmospheric conditions are constantly varying, it is obviously impossible to fix upon any size which will meet every requirement. . The only alternative, therefore, is to provide an area that will suit the majority of cases, and which will be capable of being increased or diminished according to circumstances. Dr. Parkes has pointed out that in this country a size of 24 square inches for inlet per head, and the same for outlet, is the one best adapted to meet common conditions. Theoretically, the sectional area of the outlets should vary according to the height of the foul-air flues, and the Barrack Commissioners have accordingly recommended that it should amount to 1 square inch for every 50 cubic feet of space for upper floors, to 1 square inch for every 55 cubic feet for rooms below, and to 1 square inch for every 60 cubic feet for rooms on the ground-floor, in buildings of three stories. VENTILATION AND WARMINC. 121 Practically, however, these nice distinctions may be dis- regarded, because the friction in long flues lessens very considerably the advantage in extractive power attaching to them, on account of their greater height, and also because, in the great majority of cases, the column of air in the flue increases in density the higher the flue. In prisons, where the cubic space per head is comparatively small, the sectional area of inlets and outlets should be at least 20 square inches per head. In barracks, hospitals, etc., the separate inlets should not exceed 1 square foot, other- wise the entering air will be badly distributed. More precise details with regard to the ventilation of hospitals will be given in the chapter on hospitals. 122 EXAMINATION OF AIR AND VENTILATION. CHAPTEE V. EXAMINATION OF AIR AND VENTILATION. A DETAILED examination of the sufficiency of ventilation in any particular case will embrace the following inquiries : 1. The arrangements as regards cubic space, the rela- tive size and position of inlets and outlets, the distribution of the air, and the amount of fresh air supplied. 2. The examination of the contained air by the senses. 3. Chemical examination of the contained air. 4. Microscopical examination of suspended impurities. 5. Examination as regards temperature, moisture, etc. SECTION I. EXAMINATION AS REGARDS VENTILATING ARRANGEMENTS. The measurement of the cubic space is a simple question of mensuration, but corrections must be made for furniture, bedding, etc., and for inequalities in the contour of the space to be examined. For instance, the displacement caused by solid projections into the room must be deducted, and the cubic contents of open recesses added. The allowance for each bedstead and bedding may be estimated at 10 cubic feet, and for the space occupied by the body of each person at 3 cubic feet. After the exact cubic space per head has been ascer- tained, the next points to be inquired into are the relative position and size of inlets and outlets. Perforated bricks and gratings can be approximately estimated, as regards EXAMINATION OF AIR AND VENTILATION. 123 their total open sectional area, by taking their actual superficial area, and calculating the relative size of the interstices. Inlets should be inspected as regards their freedom from accumulation of dust, etc., and outlets as regards the presence of any impediments to the ready exit of the vitiated air. Where there are open fire-places, the sectional area of the smoke-flue must also be ascer- tained. The existence or otherwise of unpleasant draughts, and the relative position of doors and windows, and how far they assist in the ventilation of the room, are other items which must not escape notice. If the system of ventilation is artificial, it should be examined in all its details, and in this examination great assistance will be derived from inspecting the architect's plans, whenever they can be procured. The directions of air-currents in a room can be ascer- tained by means of the smoke from smouldering cotton velvet, fibres of floss-silk, small pieces of feather, small balloons filled with hydrogen gas, etc. The flame of a candle is often used for the same purpose, but it is of no value when the currents are delicate, because it is un- affected by them, but is of considerable service in showing whether air is entering or issuing through any opening. Very frequently, as has already been pointed out, open- ings that are meant to be inlets act as outlets, and vice /'-/#/, or the movement of air in them may be unstable, intermittent, and reversed in its action, now entering and now issuing through the same opening. All these points, and others which may arise from peculiarities of structural arrangement, must be carefully inquired into, and the various measurements and obser- vations noted down as they are made. When the venti- lation is intended to be carried on independently of open doors and windows, these should be closed during the examination. 124 EXAMINATION OF AIR AND VENTILATION. In determining the rate of movement through the various openings, an instrument called an anemometer is generally used. This may briefly be described as a miniature windmill. The little sails, driven by the air- current, set in motion a series of small cogged wheels, which move an index or indices on a dial-plate. The velocity of the current can thus be read off for a given time, in the same way as the amount of gas which has been consumed is ascertained from a gas-meter. A very beautiful and delicate instrument of this description has been constructed by Mr. Casella of Hatton Garden, with indices on the dial-plate indicating the velocity of an air- current in feet, hundreds of feet, thousands, etc., up to millions. By moving a catch, the machinery may be stopped at any moment of time. With this instrument, the rate of movement of air through any opening is readily, and, as a rule, accurately ascertained. Before using it, the index indicating feet in units should be set at zero, and the relative position of as many of the other indices as may be deemed necessary noted down. When the instrument is placed in the air-current, time is called, and the catch moved to set the machinery free. At the end of one minute, two minutes, etc., according to the length of period of observation, time is again called, and the machinery immediately stopped by means of the catch. The linear dimension of the current is then read off, and if this is multiplied by the sectional area of the opening, the volume of air which has passed through in a given time can be easily calculated in cubic feet. When the instrument is placed in a tube or shaft, it should be put well in, but not quite in the centre, because the velocity of the current in the centre is greater than at the sides of the tube. Should the shaft be large, the rate of move- ment ought to be taken at different parts, and the average ascertained. So also, when the rate of movement is EXAMINATION OF AIR AND VENTILATION. 125 irregular, several observations should be made, and the average of the whole of them will give the approximate velocity of the current. If placed in a tube whose sec- tional area exceeds but very little the space occupied by the revolving sails, the results cannot be depended on ; and when placed at the entrance of a tube, for example, against a perforated air-brick or grating, the velocity of the current indicated by the anemometer is considerably less than what exists in the tube. In these cases the instrument should be exactly fitted into an opening in a box, large enough to cover completely the mouth of the tube, by which means the whole of the air passing through the tube may be made to pass through the opening in the box. The amount of air found to be issuing up chimneys or other outlets is a far more reliable index of the fresh- air supply than the amount actually ascertained to be entering through the inlets ; and indeed the fresh-air supply can only be fairly estimated in this way. As already stated, the air enters through every chink and cranny, and in dry plastered walls may enter, to no slight extent, through the walls themselves. Hence the difference between the amount of air found to be entering through the regular fresh-air inlets, and that found to be issuing through the outlets, is often very great. In a ward containing 15 beds, with one door, eight windows, and four inlets for fresh air, I have found that while only 880 cubic feet of fresh air were entering through the inlets per bed per hour, as much as 3150 were found to be issuing up the two chimneys and the three extraction- flues of the ward. During the experiments the door and windows were, shut, and brisk fires kept burning in the two ventilating fire-places. The large amount, therefore, of 2270 cubic feet per bed per hour entered through chinks in the window-frames, and beneath and around 126 EXAMINATION OF AIR AND VENTILATION. the closed door. Very probably, in this instance, a con- siderable amount was also drawn, by the extractive force of the chimneys and flues, through the walls, inasmuch as they were built of brick, and were only whitewashed and not plastered. When an examination of the respired air itself is intended, a suitable time must be selected, during which all the conditions of the efficiency of the ventilation, in any given instance, can be fairly put to the test. Take a hospital ward, for example. It is necessary that all the beds should be occupied, that windows and doors be kept shut, if ventilation is intended to be effectually carried on without them, and that an hour should be selected in the night-time when the greatest accumula- tion of impurities is likely to occur. Any hour between midnight and 5 A.M. would meet this condition in most cases. In order to make the examination as complete in detail as possible, it is necessary to have a wet and dry bulb thermometer placed outside some time previ- ously, and several others fixed at different positions in the ward. The outside and inside temperature can thus be compared, and the relative hygometricity of the air indoors and outdoors ascertained. If the barometer is read off at the same time, and the state of the weather recorded, all the meteorological data are obtained which are usually considered necessary for a full and exhaustive report. SECTION II. THE EXAMINATION OF THE CONTAINED AIR BY THE SENSES. With a little practice, this method of examination gives tolerably reliable results ; but it is necessary that one should remain for some short time in the open air, before entering the ward or room to be examined, other- wise the sense of smell is likely to be blunted and unable EXAMINATION OF AIR AND VENTILATION. 127 to appreciate the degree of closeness or foulness. One of the terms, " not close," " rather close," " close," " very close," "foul," "very foul and offensive," will indicate, with sufficient accuracy, the degree of perceptible impurity in the majority of cases. The following selections from Dr. de Chaumont's experiments show how closely the sensations accord with the different degrees of impurity indicated by the percentage of carbonic acid : . f Extremely close At '0843 per cent. Not very foul. At '1408 per cent. J -,. \andunpleasant. ,, '0804 ,, Close. ,, -1090 ,, Extremely close, j ,, '0658 ,, Not very close. ,, -0962 ,, Very close. j '0568 ,, Not close. ,, -0921 Close. SECTION III. CHEMICAL EXAMINATION. 1. Carbonic Acid. In the chemical examination of respired air, the chief point to be determined is, the amount of carbonic acid per 1000 volumes. Petten- kofer's method is the one most generally adopted, because it is alike accurate and easy of application. For the analysis, which is volumetric, French weights and measures are used. The following apparatus and solutions are also required. (1.) Two or more glass jars, each capable of holding 4000 to 6000 centimetre cubes, and fitted with india- rubber caps. (2.) A Mohr's burette, graduated into centimetre cubes and tenths, fitted with pinch-cock, and large enough to hold 50 or 100 centimetre cubes. (3.) A narrow glass measure, marked to measure 30 and 60 centimetre cubes exactly. (4.) A pair of bellows or a bellows-pump. (5.) Turmeric paper specially prepared. (Turmeric powder should be boiled in alcohol, and ordinary filtering paper steeped in it, then washed and dried.) 128 EXAMINATION OF AIR AND VENTILATION. (6.) Pure clean lime water. (Both Dr. Angus Smith, and lately Pettenkofer, prefer baryta water, but I follow in my description the plan pursued by Drs. Parkes and de Chaumont, according to which my own analyses have been made.) (7.) A solution of crystallised oxalic acid, 2*25 grammes to the litre of distilled water. The capacity of the glass jars must be accurately determined by means of a litre measure graduated into centimetre cubes, and it is convenient to affix the cubic contents, expressed in centimetre cubes, to each jar. Before being used it is necessary that the jars should be perfectly clean and dry. The analysis depends on the relative degree of caus- ticity of the lime water before and after it has absorbed the carbonic acid contained in the sample of air to be examined. Thus 1 cubic centimetre of the above solu- tion of oxalic acid exactly neutralises 1 milligramme ('001 gramme) of lime ; and hence the amount of lime con- tained in a given quantity of lime water can be readily determined by adding the solution until the point of neutralisation is reached. The amount of oxalic acid solution required for neutralisation expresses the causticity of the lime water. If now the causticity of the lime water is known before and after it has absorbed the carbonic acid in the air contained in the glass jar, the difference will give the amount of lime in milligrammes which has united with the carbonic acid, and the amount of the latter is obtained by calculating according to the atomic weights. The amount of neutralisation is determined by means of the turmeric paper. The test solution of oxalic acid should be run into the measured quantity of lime water from the burette, and the mixture constantly stirred with a glass rod. Every now and again a small drop of the EXAMINATION OF AIR AND VENTILATION. 129 mixture is conveyed on the tip of the rod to the turmeric paper, and one can readily judge by the tint of the stain when the point of neutralisation is approached. With pure lime water the stain produced is an intense dark brown, and as the oxalic acid solution is added, it becomes gradually paler on each application, until at last the centre of the stain is not tinted, and the margin alone appears as a delicate brown ring. The solution should now be carefully added drop by drop, and when the tint of the ring also disappears, the point of neutralisation has been reached. In making a single analysis it is advisable to use two jars, because otherwise a repetition of the experiment would not be possible were it required. Under ordinary circumstances, however, as many analyses can be made as there are jars used for collecting samples of the air from different parts of the same room or building. The air to be examined is forced into the jars by means of a pair of bellows, and, by a suitable arrangement of tubing con- nected with the bellows, it can be pumped into them from any part of the room. In the case of small occupied spaces, such as prison-cells, when it is not desirable to disturb the ventilation by opening the door, the contained air can in this way be pumped into the jars through any opening, such as the inspection hole in the door, care being taken that the tubing and its connection with the bellows are perfectly air-tight, and that the bellows-valve acts efficiently. Instead of bellows, a bellows-pump may be used, but in either case the nozzle should be long enough to reach the bottom of the jar. Dr. Angus Smith prefers using the bellows-pump, exhausting the air in the jar, and thus ensuring that its place shall be taken by the air to be examined. Pettenkofer and Dr. - de Chaumont, on the other hand, pump the air into the jar ; but either method K 130 EXAMINATION OF AIR AND VENTILATION. answers very well, provided that care be taken that the jar is really rilled with the air to be examined. After the jar has been filled, 60 cubic centimetres of lime water are introduced, and the mouth of the jar closed by a tight-fitting india-rubber cap. If tubing has been used to convey the air from a distant part of the room, or from a small inhabited place without entering it, it is necessary that this part of the experiment should be performed rapidly, in order to prevent escape by diffusion, and therefore the measured quantity of lime water should be ready to be poured into the jar whenever the nozzle of the bellows is withdrawn. The jar is then well shaken, so that the lime water is made to wash the contained air thoroughly, and afterwards is left to stand for a period of not less than six or eight hours, and not more than twenty-four. 60 cubic centimetres are introduced, in order that 30 may be taken out for analysis. So much of the lime water adheres to the sides of the jar that the whole amount introduced cannot be poured out ; and hence, if a repetition of the experiment is necessary, another jar must be used. In making the analysis, 30 cubic centimetres of the lime water which has been employed are poured into a mixing jar, and its causticity determined as above de- scribed by the test solution. Then 30 cubic centimetres are taken from the jar, and the causticity also determined. The causticity of the lime water is found to vary from 34 to 41, according to its strength: in other words, from 34 to 41 cubic centimetres of the oxalic acid solution will be required for neutralisation, while the causticity of the lime water in the jar will be lessened in proportion to the amount of carbonic acid in the contained air. The differ- ence between the first and second operations is doubled to account for the 30 cubic centimetres left in the jar, and the product gives the amount of lime which has com- EXAMINATION OF AIR AND VENTILATION. 131 bined with the carbonic acid. The amount of the latter, as already observed, is obtained by converting weight into measure according to the atomic weights, and in one sum tbe factor is found to be '39521. The capacity of the jar being known, and a deduction of 60 cubic centi- metres made for the space occupied by the lime water, the amount of carbonic acid becomes a question of simple proportion. Thus, to take an example Suppose the causticity of 30 cubic centimetres of the lime water is 39'5, and the causticity of the lime water in the jar is 3 3 '5 ; suppose also that the capacity of the jar is 5060 cubic centimetres ; then, to find the ratio of carbonic acid per 1000 volumes, that is per 1000 cubic centimetres, the problem is as follows : (5060-60) :1000::[(39-5-33-5)x2x'3952l] :X therefore X = ^p^=-948 carbonic acid per 1000 volumes. It will thus be seen that the calculations may be simplified by adopting the following rule : Multiply the difference between the causticity of the lime water, before and after it has been placed in the jar, by 790, and divide this sum by the number of centimetre cubes contained by the jar, minus 60. The result will be the ratio of car- bonic acid per 1000 volumes. But a certain correction must be made for tempera- ture, according as it is above or below the standard of 62 Fahr. As the co-efficient of expansion of air is 0020361 for every degree Fahr., the rule for correction may be stated with sufficient accuracy thus : For every 5 above 62 add 1 per cent to the amount of carbonic acid calculated as above, and deduct the same percentage for every 5 below 62. If the place of observation is much above the sea- level, a correction must also be made for the difference of atmospheric pressure. The standard barometric pressure being 30, the formula for this correction is as follows : 132 EXAMINATION OF AIR AND VENTILATION. 3 : (observed height of barometer) : : capacity of jar : Z. The result expressed by Z is substituted for the actual capacity of the jar in the calculation for carbonic acid. Amongst various popular tests for the estimation of the carbonic acid in air vitiated by respiration, the follow- ing, proposed by Dr^_Ajigu JSDaith, is worthy of notice, because it does not require skilled manipulation, nor is it hampered with troublesome measurements or calculations. The method is based upon the fact that the amount of carbonic acid in a given quantity of air will not produce a precipitate in a certain given quantity of lime water, unless the carbonic acid is in excess. This will be better understood by comparing the different columns in the subjoined table, which is taken from Dr. Smith's work on Air and Rain : EASIEST PROPOSED HOUSEHOLD METHOD. TABLE. To be used when the point of observation is " No pre- cipitate." Half an ounce of lime water containing *0195 gramme lime. Air at C. and 760 Millim's bar. Carbonic acid in the air. Per cent. Volume of air in cubic centimetres. Size of bottle in cubic centimetres. Size of bottle in ounces avoirdupois. 03 571 584 20-63 04 428 443 15-60 05 342 356 12-58 06 285 299 10-57 07 245 259 9-13 08 214 228 8-05 09 190 204 7-21 10 171 185 6-54 11 156 170 6-00 12 143 157 5-53 13 132 146 5-15 14 123 137 4-82 15 114 128 4-53 20 86 100 3-52 25 69 83 2-92 30 57 71 2-51 EXAMINATION OF AIR AND VENTILATION. 133 Columns 1 and 2 give the ratio of carbonic acid in the quantity of air which will produce no precipitate in half an ounce lime water; column 3 is the same as column 2, with the addition of 14' 16 cubic centimetres, or half an ounce, to give the corresponding size of bottle ; and column 4 gives the size of bottle in ounces avoir- dupois. It will thus be seen that different-sized bottles containing half an ounce of lime water will indicate ap- proximately the ratio of carbonic acid in the air contained in them, by giving no precipitate when the bottle is well shaken. Thus, if a bottle of 1 oz. is used, and there is no precipitate, it will indicate that the ratio of carbonic acid does not exceed '06 per cent; or if one of 8 oz. is used, and there is also no precipitate, it will indicate that the ratio does not exceed "08, and so on. Dr. Smith says that " the lime w r ater may be prepared of the same con- stant strength so closely that we may neglect the differ- ence. Burnt lime is slaked with water and dissolved by shaking. It is then kept in a bottle to stand till it is clear. The bottle or bottles used should be wide-mouthed, so that they can be readily cleaned and dried, and the air to be examined may be made to enter them by inhaling the air contained in them through a glass or caoutchouc tube, care being taken not to breathe into the bottle." As a practical application of this method, which can be practised by any one, Dr. Smith proposes the following rule : " Let us keep our rooms so that the air gives no precipitate when a 10^ oz. bottleful is shaken with half an ounce of clear lime water." 2. Organic Impurities. To obtain an approximate estimate of the organic impurities, the air may be drawn through, or washed, in a very dilute solution of potassium permanganate of known strength. The result is stated in the number of cubic feet of air which it takes to decolourise 001 gramme of the potassium permanganate in solution. 134 EXAMINATION OF AIR AND VENTILATION. The method pursued by Dr. Angus Smith is somewhat different from this. He takes about 3 cubic centimetres of -pure water, and adds to it a small amount of known solution of the potassium permanganate. This solution is shaken up with the air in the bottle ; the air is then drawn out by a bellows-pump, and another bottleful washed, and so on until the whole colour is removed, or a sufficient amount to enable him to test the remainder, so as to be able to estimate the difference. The actual amount of oxygen taken is then calculated, and the results stated in grains per million cubic feet of air. 3. Ammonia. The estimation of the ammonia, organic and albuminoid, is a still more delicate and difficult pro- cess. The water used for washing the air must be per- fectly pure, and should therefore be boiled with soda or potash before distillation. From 30 to 50 cubic centi- metres are then introduced into a bottle of about 2000 cubic centimetres, and the washing of successive bottlefuls of the air to be examined is continued until the water is sufficiently charged with impurities. A more exact method is to draw the air through* distilled water by means of an aspirator of known dimensions, which, whether charged once or several times, will indicate accurately the amount of air whose impurities are to be tested. The testing afterwards is the same as that proposed by Messrs. Wanklyn, Chapman, and Smith, for organic impurities in water, and the results are stated in grains per million cubic feet of air. For further information concerning these methods of analysis, and for an account of numerous valuable experi- ments, see Dr. Angus Smith's work already quoted, and Dr. Fox's work on the Sanitary Examinations of Water, Air, and Food. EXAMINATION OF AIE AND VENTILATION. 135 SECTION IV. MICROSCOPICAL EXAMINATION. Suspended matters contained in the air may be col- lected by drawing the air through distilled water by means of an aspirator, by washing the air in distilled water, or by employing an instrument called an aeroscope. When either of the first two processes is employed, the suspended matters are merely allowed to subside, and are then removed to a glass slip for examination. The aeroscope invented by Pouchet consists of a funnel-shaped tube, ending in a fine point, beneath which is placed a slip of glass moistened with glycerine. Both glass and tube are enclosed in an air-tight chamber, which is connected by tubing with an aspirator, so that when the stopcock of the aspirator is turned, and the water allowed to escape, the air is drawn through the tube, and impinges against the slip of glass moistened with glycerine, by which the suspended matters are arrested. SECTION V. EXAMINATION AS REGARDS TEMPERATURE AND MOISTURE. 1. Temperature. The various points connected with the temperature of the contained air, such as its equability, sufficiency, etc., are readily ascertained by a judicious dis- tribution of thermometers throughout the space to be examined, and by comparing the outside with the inside temperature. The efficiency of the heating apparatus is of course best tested during very cold weather and in the night time. When open fire-places are used the tempera- ture should be noted at the remote parts of the room, and if the air is heated before entering, it is advisable to take x the temperature at the point of delivery, and to ascertain whether it is well diffused or not. 2. Moisture. The amount of watery vapour, or the 136 EXAMINATION OF AIR AND VENTILATION. hygrometricity of the contained air, may be determined by hygrometers such as Daniell's and Eegnault's, or by wet and dry bulb thermometers. The latter are the most convenient and reliable, but they should be distributed some two or three hours before the observations are made. The wet bulb is covered with muslin, over which there is twisted a small skein of cotton, which dips into a little vessel containing either distilled or rain water. The cotton should be boiled in ether, or soaked in a solution of sodium carbonate, to free it from fat, so that the water may readily ascend by the force of capillary attraction. Unless the air is saturated with moisture, the tem- perature of the wet bulb is always below the temperature of the dry, and the number of degrees of difference be- tween them varies according to the amount of watery vapour present. This is generally represented in relative terms. For example, the point of complete saturation being assumed to be 100, any degree of dryness may be stated as a percentage of this, and can be conveniently ascertained by reference to the table given on the opposite page, which has been calculated from Mr. Glaisher's large tables. The table is read by taking the temperature of the dry bulb, and the difference between it and that of the wet bulb, and noting the number given at the inter- section of the two columns. This number gives the relative humidity. The relative humidity of the air out of doors should also be ascertained at the same time, by way of com- parison. In carrying out experiments in ventilation, thejiajr- hygrometer gives sufficiently accurate results, and possesses a considerable advantage over the dry and wet bulb ther- mometer in rapidity of indication. It consists of a human hair freed from fat by steeping it in ether or a solution of liquor potassse, one end of which is fixed, and the other TABLE of the Relative Humidity given by the difference between the Dry and Wet Bulb. 137 = ' 8 Ss |pq S*& 1 fi DIFFERENCE BETWEEN THE DRY AND WET BULB. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 RELATIVE HUMIDITY, SATURATION = 100. 90 100 95 90 85 81 77 73 69 65 62 59 56 53 50 47 44 89 100 95 90 85 81 77 73 69 65 01 58 55 52 49 46 43 88 100 95 90 85 81 77 73 69 65 01 58 55 52 49 46 43 87 100 96 90 85 81 77 73 69 65 61 58 55 52 49 46 43 86 100 95 90 85 80 76 72 68 64 61 58 55 52 49 46 43 85 100 95 JO 85 80 76 72 68 64 61 58 55 52 49 46 43 84 100 95 90 85 80 70 72 68 64 60 57 54 51 48 45 43 83 100 95 90 85 80 70 72 68 64 60 57 54 51 48 45 42 82 100 95 90 85 80 70 72 68 64 60 57 54 51 48 45 42 81 100 95 90 85 80 76 72 68 64 60 56 53 50 47 44 41 80 100 95 90 85 80 75 71 67 63 59 56 53 50 47 44 41 79 100 95 90 85 80 75 71 67 63 59 56 53 50 47 44 41 78 100 94 89 84 79 75 71 67 63 59 56 53 50 47 44 41 77 100 94 89 84 79 75 71 67 63 59 56 53 50 47 44 41 76 100 94 89 84 79 75 71 67 63 59 55 52 49 46 43 40 75 100 94 89 84 79 74 70 66 62 58 55 52 49 40 43 40 74 100 94 89 84 79 74 70 66 62 58 55 52 48 45 43 40 73 100 94 89 84 79 74 70 66 62 58 54 51 48 45 42 40 7'2 100 94 89 84 79 74 69 65 61 57 54 51 48 45 42 39 71 100 94 88 83 78 73 69 65 61 57 53 50 47 44 41 38 70 100 94 88 83 78 73 69 65 61 57 53 50 47 44 41 38 69 100 94 88 83 78 73 68 64 60 56 53 50 47 44 41 38 68 100 94 88 83 78 73 68 64 60 56 52 49 46 43 40 37 67 100 94 88 83 7S 73 68 64 60 56 52 49 46 43 40 37 06 100 94 88 83 78 73 68 64 60 56 52 48 45 42 40 37 65 100 94 88 83 78 73 68 63 59 55 51 48 45 42 39 36 04 100 94 88 82 77 72 67 63 59 55 51 48 45 42 39 36 03 100 94 88 82 77 72 07 63 59 55 51 47 44 41 38 35 62 100 94 b^ 82 77 72 67 62 66 55 50 47 44 41 38 35 61 100 94 88 82 77 72 67 62 58 54 50 47 44 41 38 35 60 100 94 BS 82 76 71 66 62 58 54 50 46 43 40 37 34 59 100 94 88 82 76 71 66 61 57 53 49 46 43 40 37 34 58 100 93 67 81 76 71 66 61 57 53 49 46 43 40 37 34 57 100 93 87 81 75 70 65 61 57 53 49 45 42 39 36 33 56 100 93 87 81 75 70 65 60 56 52 48 44 41 38 35 32 55 100 93 87 81 75 70 65 60 56 52 48 44 41 38 35 32 54 100 93 86 80 74 69 64 59 55 51 47 43 40 37 34 31 53 100 93 86 80 74 69 64 59 55 51 47 43 39 36 33 30 52 100 93 80 80 74 69 64 59 54 50 46 42 39 36 33 30 51 100 93 86 80 74 68 63 58 54 50 46 42 38 35 32 29 50 100 93 86 80 74 68 63 58 53 49 45 41 37 34 31 29 49 100 93 86 79 73 07 62 57 53 49 45 41 37 34 31 28 48 100 93 86 79 73 67 62 57 52 48 44 40 36 33 30 47 100 93 86 79 73 07 61 56 51 47 43 39 36 33 30 46 100 93 86 79 73 07 61 56 51 47 43 39 35 32 29 45 100 92 85 78 72 66 60 55 50 46 42 38 34 31 28 44 100 92 84 78 71 65 59 54 49 45 41 37 34 31 28 43 100 92 84 78 71 65 59 54 49 45 41 37 34 31 28 42 100 92 84 78 71 64 59 54 49 44 40 36 34 30 27 41 100 92 84 77 70 64 58 53 M 43 39 35 31 28 40 100 92 84 77 69 03 57 52 47 42 38 34 31 39 100 92 84 77 69 57 51 46 42 38 34 38 100 91 83 75 68 62 56 50 45 41 37 37 100 91 83 75 68 01 55 49 44 39 36 100 91 82 74 66 59 53 47 42 35 100 90 80 72 34 100 89 79 72 33 100 89 78 70 100 87 75 138 EXAMINATION OF AIR AND VENTILATION. attached to a small needle, and according as the hair becomes shorter or elongates, the needle traverses a gradu- ated scale, and thus indicates the relative humidity. After a time, however, it loses its delicacy, and requires to be readjusted. In a room well ventilated and warmed the humidity ought to range between 73 and 75 per cent, the tem- perature should not fall below 60 Fahr., and the car- bonic acid, as previously stated, should not exceed *6 per 1000 volumes. In the examination of the air contained in the crowded dwellings of the poorer classes, the senses will alone suffi- ciently indicate the degree of impurity, but in all cases the cubic space per head, and the means of ventilation, should be carefully noted, because otherwise any sugges- tions as regards improvements will at the best be hap- hazard, and possibly ill-advised. The amount of cubic space obtainable in the houses of the poor, and especially in rural districts, will be more fully discussed in Chapters IX, and XVI. WATER. 139 CHAPTER VI. WATER. SECTION I. SOURCES. ALL supplies of fresh water are derived from the con- densation of the aqueous vapour contained in the atmosphere. Whether this falls to the earth in the form of rain or snow, a certain portion of it runs off the sur- face and gravitates towards the sea ; another portion sinks into the soil, and, passing through strata which are more or less porous, or through fissures in rocks, again reappears in springs and wells ; a third portion is evaporated where it falls; and the remainder becomes absorbed in the chemical composition of minerals, or is utilised in the pro- cesses of growth and decay of animal and vegetable life. The rainfall which flows on the surface collects in streams, lakes, and rivers, according to the conformation of the ground, while the water flowing under ground oozes to the surface either imperceptibly or in springs, and eventually unites with the surface water in its accumula- tion in lakes, or in its onward progress towards the sea. The immediate sources of water-supply may therefore be classified as rain water and water from springs, wells, rivers, or lakes. 1. Rain Water. Rain Water is highly aerated, and, when uncontaminated by the receiving surface or by air- impurities', is healthy and pleasant. But frequently, 140 WATER. according to the analyses of the Elvers Pollution Com- missioners, it contains a large amount of organic matter, and in this country is usually far less pure than water derived from deep wells and springs. This is not to be wondered at, when we consider that the atmosphere in a thickly populated country like Great Britain becomes the recipient of vast quantities of excremental dust and effluvia, of smoke particles, and the products of animal and vegetable decay. It is, therefore, seldom stored on premises except for washing purposes, but in Venice and many other continental cities it is collected in underground reservoirs, and constitutes almost the sole source of fresh- water supply to the inhabitants. It is usually collected from the roofs of houses, and occasionally from paved or cemented ground. In hilly districts with deep ravines, it may be stored by carrying an embankment across a valley, or, in level districts, by digging a series of open trenches leading to a tank or reservoir. The amount of water derivable from the rainfall in given cases is readily ascertained, if the mean annual rainfall of the district is known, and the dimensions of the receiving area are obtained. Thus, when the roofs of houses constitute the receiving area, the transverse section of the buildings will be one factor, and the mean annual rainfall the other. It has been estimated that the quan- tity which can be collected from the roof surface of any town in this country will scarcely amount to 2 gallons per inhabitant daily, assuming that the average rainfall is 20 inches, and that house accommodation gives a roof area of 60 square feet for each individual. If lines be drawn through the sources of the tribu- taries of rivers marked on a map, they will be found to form the boundaries of certain areas which are called the catchment basins of the various rivers that is, the areas which receive the rainfall supplying their waters. In WATER. 141 compact formations, where most of the rain runs off the surface, the ridge lines bounding these basins usually pass along the most elevated regions, but in porous formations their course will depend on the configuration of the reten- tive substratum. The amount of rainfall which penetrates beneath the surface varies according to the density and configuration of the ground, and also depends on whatever influences / / the rate of evaporation. Thus in loose sandy or gravelly districts as much as 90 to 96 per cent sinks into the soil; in chalk districts, 42 ; in limestone, 20; while in districts of retentive, impermeable clay, the percentage is very small. Dr. Dalton, in his experiments on the new red sandstone soil of Manchester, found that 2 5 per cent of the whole rainfall penetrated to the depth of 3 feet ; and Mr. Prestwich gave the amount of infiltration of the principal water-bearing strata surrounding London as vary- . ing from 48 to 60 per cent. Other things being equal, the amount of infiltration will be far less in an undulating hilly district than in open, level plains. It is obvious also that it must vary very considerably with the season of the year. Thus, according to the experiments of Mr. Dickinson, made in the gravelly loam which covers the chalk in the valleys around Watford, it was 70 per cent in the first three months of the year ; in the summer months it was only 2 ; while in November and December nearly the whole of the rainfall penetrated beneath the surface. 2. Water from Wells, Springs, Rivers, and Lakes. The quality and composition of the water derived from these sources depend on the nature of the soil and geolo- gical strata through which it has passed, or on the character of its surface-bed or channel. The rain, already charged with carbonic acid in its passage through the lower regions of the atmosphere, becomes still more 142 WATER. largely impregnated with this gas when it sinks beneath the surface. In some rich soils, the amount present in the air contained within their interstices, according to Boussinganlt, is 250 times greater than the ordinary atmospheric ratio. Aided by the action of the carbonic acid which it has thus absorbed, the rain water dissolves and decomposes various chemical compounds which it meets "with in its underground progress, and often be- comes so highly charged with them as to become unfit for ordinary use, as in the case of mineral waters. (1.) Surface or shallow-well waters, though some- times comparatively pure, frequently contain a large amount of organic matter. In mossy moorland districts, for example, or in rich vegetable soils, the water may contain from 12 to 30 grains of vegetable matter per gallon, which imparts to it a yellowish or brownish tint ; while in marshy districts the amount of organic matter varies from 10 to 100 grains. The saline constituents depend very much upon the geological character of the stratum in or upon which the well is sunk, but in in- habited places these are often masked by the products of excremental pollution. Shallow-well waters are drawn from wells not more than 50 feet deep, and seldom ex- ceeding half that depth. Surface waters from cultivated land are always more or less contaminated with manurial impurities, and should therefore be efficiently filtered before being used. (2.) The water from deep wells and springs varies according to the geological strata through which it passes. Thus alluvial waters are more or less impure, containing a large amount of salts (20 to 120 grains per gallon), and often much organic matter ; while the chalk waters are clear, wholesome, and sparkling, holding in solution a considerable amount of calcium carbonate besides other salts, and being largely impregnated with carbonic acid. WATER.- 143 Also wholesome and agreeable to the taste, but not so suitable for cooking purposes, is the water from the lime- stone and magnesian limestone strata. It contains more calcium and magnesium sulphate than the chalk water, and consequently does not become so soft on boiling. Waters from the granitic, metamorphic, trap -rock, and clay-slate formations, are generally very pure, and con- tain but small quantities of solids, consisting chiefly of sodium carbonate and chloride, with a little lime and magnesia. Waters from the millstone grit and hard oolite are also very pure. The saline constituents are by no means excessive, and are chiefly in the form of calcium and magnesium sulphate and carbonate, with traces of iron. Soft sand -rock waters, loose sand and gravel waters, and waters from the lias clays, vary very much in quality and composition, some of them being very pure, as the Farnham waters, and others containing large amounts of mineral and organic matters. (3.) River water is in most cases softer than spring or well water. It contains a smaller amount of mineral salts, but is often largely impregnated with organic matter on account of the vegetable ddbris and animal excreta which find their way into it. Its constant movement, however, facilitates the oxidation of organic impurities, and this purifying process is aided to some extent by the presence of fresh-water plants. (4.) Lake water, especially in mountainous districts composed of the older rock formations, is generally very soft, containing little mineral matter ; but as it is essen- tially a stagnant water, and as all lakes receive the wash- ings of the districts in which they are situated, the amount of organic nitrogenous matter is sometimes very consider- able. Any excess, however, of peaty matter in solution may be materially lessened by filtering through sand. As regards the qualities of potable waters founded 1 44 WATER. upon their respective sources, the following classifications are given by the Kivers Pollution Commissioners in their Sixth Eeport : I. In respect of wholesomeness, palatability, and general fitness for drinking and cooking : 1. Spring water. 1 , r , IT1 , h Very palatable. Wholesome. -{ 2. Deep-well water. 3. Upland surface water. "I Moderately 4. Stored rain water. / palatable. f 4. Stored ram water. Suspicious. \ 5. Surface water from cultivated ^ I land. f 6. River water to which sewage j- Dangerous. gains access. 1 7. Shallow-well water 6. River water to which sewage } Palatable. II. According to softness : 1. Rain water. 2. Upland surface water. 3. Surface water from cultivated land 4. River water. 5. Spring water. 6. Deep-well water. 7. Shallow- well water. III. In respect of the influence of geological forma- tion in rendering water sparkling, colourless, palatable, and wholesome, by percolation, the following water- bearing strata are given as the most efficient : 1. Chalk. 2. Oolite. 3. Greensand. 4. Hastings sand. 5. New red and conglomerate sandstone. SECTION II. QUANTITY NECESSARY FOE HEALTH AND OTHER PURPOSES. A healthy adult requires daily from 70 to 100 oz. of water for the processes of nutrition, about one -third of WATER. 145 which is contained in articles of diet, the other two-thirds being supplied in the form of liquids. The amount for cooking has been estimated at from half a gallon to a gallon daily for each person, while the quantity deemed necessary for personal cleanliness and for washing pur- poses will necessarily vary very much according to the habits of the individual. Dr. Parkes has given the following quantities used by a man in the middle class : Gallons daily. Cooking -75 Fluids as drink ...... '33 Ablution, including a daily sponge-bath . 5 Share of utensil and house washing . . 3 Share of clothes washing .... 3 12-08 The soldier is allowed about 1 5 gallons daily, no extra allowance being given for the women and children in a regiment. In the poorer districts of the city of London, Dr. Letheby found that the amount used was 5 gallons per individual daily, and in model lodging-houses, accord- ing to Mr. Muir, 7 gallons. In the cottages of the poor in country districts where water is scarce, the amount in many instances does not exceed 3 gallons, but then the inhabitants are not cleanly. A shower-bath daily will require 3 to 4 gallons, while a plunge-bath will take from 40 to 60 gallons. Where water-closets are used, an additional allowance of from 4 to 6 gallons must be pro- vided. Latrines require a less amount. In gross amounts Professor Rankine has given an estimate of 10 gallons daily per individual for domestic purposes, 10 for municipal purposes, and 10 more for trade purposes in manufacturing towns, and this amount, large though it seems, is actually supplied to many towns at the present day. Glasgow, for example, receives 50 L 146 WATER. gallons daily per head of population; Edinburgh and Southampton 35; Paris 31; and Liverpool 30. The different London water companies supply from 21 to 34 gallons the mean average being 2 8 ; while the manu- facturing towns in Lancashire and Yorkshire, according to Mr. Bateman, received from 16 to 21 gallons. In Norwich the average supply is only 12 gallons, and in Derby 14. Mr. Eawlinson's minimum estimate for manufacturing towns is 20 gallons per head daily, and if care be taken to prevent needless waste this amount will be quite sufficient. There is no doubt that a large pro- portion of the waste is connected with water-closets, ajid especially those which are directly flushed from the mains, and, as an instance in point, I may mention that when all such direct communication was cut off in the town of Warwick on my recommendation, the supply was reduced from 33 to 20 gallons per head daily. In apportioning the daily allowance for all purposes, Dr. Parkes has given the following estimate : Gallons per head of population. Domestic supply . . . . . . 12 General baths 4 Water-closets ....... 6 Unavoidable waste ...... 3 Total house supply ...... 25 Municipal purposes ...... 5 Trade purposes 5 Total 35 No doubt this estimate may be regarded as somewhat excessive, especially in the items of domestic and water- closet supply, but it has been based on the principle that a liberal allowance is not only necessary for thorough cleanliness, but that it is also required for an efficient clearage of sewers. There can be no question, however, WATER. 147 that the amount of water habitually wasted in many towns is enormous, reaching in all probability to at least one third of the supply, and this, when the water has to be pumped into the town, or when the town sewage has to be pumped or chemically treated in any way at the outfall, increases the rates to a very considerable extent. While part of this waste is due to underground leakage from pipes and mains, by far the larger portion of it is due to imperfect household fittings, and to carelessness in leaving stool-cocks and bib-cocks open in connection with water-closets whose flush pipes communicate directly with the mains. All closets should be provided with cisterns of the waste-preventing class, but of sufficient capacity to flush the closet-pan when used. For hospitals the daily amount per patient may be estimated at about 30 gallons. In prisons and work- houses the quantity will vary according to the bathing arrangements, and whether water-closets are used. In the Convict Prison, Portsmouth, where water-closets and water-latrines are both in use, and where each prisoner is allowed a general bath once a week, I found that the amount averaged about 11 gallons per convict daily. SECTION III. MODES OF SUPPLY. This part of the subject has reference to wells, borings, the collection and storage of water, and to waterworks generally. 1. Wells and Borings. In small urban and rural districts surface wells, whether as ordinary pump wells, draw wells, or shallow dip wells, constitute the usual source of supply, and though they may naturally yield a wholesome water, the surrounding soil often becomes so saturated with impurities that it is next to impossible to prevent their pollution. In crowded localities, therefore, 148 WATER. they should always be regarded with suspicion, and, as far as possible, their use should be discontinued. Deep wells, on the other hand, are not open to this objection, because they are generally sunk through an impervious stratum, which prevents the infiltration of any surface impurities, and at the same time serves to keep down the water in the porous strata beneath. The quality of the water from these wells, as has already been shown, will depend on the nature of the geological formation of the district. It is also apparent that, in accordance with a well-known physical law, it is only necessary to bore through the impervious stratum, and reach the water-bearing bed, for the water to rise to the surface, or to within a short dis- tance of it, so as to be collected in a well of ordinary dimensions. Indeed, in certain low-lying districts, where a boring is made at a point considerably below the level of the line of infiltration into the water-bearing stratum, the water rises above the surface and overflows. Such overflowing wells, or artesian wells as they are called, were once common in the valley of the Thames, and are still to be met with in the flat lands of Essex and on the coast of Lincolnshire. Ordinary borings differ from artesian wells in not piercing through a retentive stratum in order to reach the water-supply. They are very common in the chalk and new red sandstone districts, and are made to increase the yield of the wells. Practically, it is found that one boring adds to the supply of a well nearly as much as several. Thus in the Bootle well at Liverpool, with 16 bore -holes, some of which were 600 feet deep, Mr. Stephenson found that when all were plugged up but one, the yield was 921,192 gallons per day, and when all were open it was only increased by 112,792 gallons. Deep wells are now being abandoned for the supply of large towns, because they are found to be insufficient WATER. 149 for the wants of a rapidly - increasing population, and obviously cannot be multiplied within a given district beyond certain limits, because every single well drains a surrounding area of some considerable extent. For large isolated buildings, however, such as lunatic asylums, workhouses, and prisons, they usually supply the whole of the water required ; and in selecting a site in the country for any such building, the possibility of obtaining the requisite water-supply, and the cost at which it can be procured, are points of the first importance. Generally speaking, the chance of obtaining a good supply will depend upon the nature of the underlying strata, and upon the level of the proposed site. Wells sunk in superficial sand or gravel beds, though yielding a good supply at ordinary times, are very liable to have their yield very much lessened in seasons of drought, unless they are situated at points considerably below the level of the surrounding country, and the same remark applies to surface wells in the chalk districts. On the other hand, deep wells or borings in the new red sand- stone, and oolite or chalk formations, usually yield a large and constant supply, because these permeable rocks are so saturated with water that they may be regarded as vast subterranean reservoirs. The deepest artesian wells in the world are those at Grenelle in Paris and Kissengen in Bavaria, the former being 1800 and the latter 1878 feet in depth. The Commissioners, in the report already alluded to, strongly urge " that preference should always be given to spring and deep-well water for purely domestic purposes, over even upland surface water, not only on account of the much greater intrinsic chemical purity and palatability of these waters, but also because their physical qualities render them peculiarly valuable for domestic supply. They are almost invariably clear, colourless, transparent, 150 WATER. and brilliant, qualities which add greatly to their accept- ability as beverages ; whilst their uniformity of tempera- ture throughout the year renders them cool and refreshing in summer, and prevents them from freezing readily in winter. Such waters are of inestimable value to com- munities, and their conservation and utilisation are worthy of the greatest efforts of those who have the public health under their charge." The following are some of the towns which are sup- plied by deep wells : Canterbury, Cambridge, Bury St. Edmunds, and Deal, from the chalk formation ; Birken- head, Coventry, Leamington, and Southport, from the new red sandstone; and Bedford and Scarborough from the oolite. For a small or temporary supply the American tube well (Norton's patent) has been found to be very useful. It consists of a narrow iron tube driven into the ground in lengths, the lower part being pointed and perforated at its end, and is fitted with a single or double action pump according to the depth. The water enters the tube through the perforations, and, if the bed is sandy, has to be filtered for some time, until, by gradual removal of the sand, a well is formed around the lower end, and the water is obtained without sediment. This pump is especially adapted for country districts, and it possesses the further advantage of helping to keep out surface impurities. In order to ascertain the yield of surface wells, the water must be pumped out, and the time noted which is required for refilling. The yield of small springs can be readily measured by receiving the water into a vessel of known dimensions, such as a cask, and also noting the time which it takes to fill. 2. Waterworks. In addition to deep wells, water- works on an extensive scale obtain their supply from WATER. 151 lakes, streams, rivers, or gathering -grounds. If from a lake of sufficient elevation above the level of the town to be supplied, the water may be distributed throughout the town in conduits and pipes by the force of gravity. When the source of supply is a stream or small river, storage works are necessary ; but when the river is large, a constant supply can be obtained at all times, independ- ently of storage. In this case, the works required usually comprise a weir or. dam for maintaining part of the river at a nearly constant level ; two or more settling- ponds, into which the water is conducted ; filtering appa- ratus, and pumping engines. When it is required to ascertain the yield of any small stream, it is usual to employ a weir-gauge to dam up the water into a pond behind, and allow it to flow through a sluice or over a sill of known dimensions. In the case of an average-sized stream, a rough approxima- tion of the yield may be obtained by taking the breadth and depth at several distances in a short section of the channel which is tolerably uniform, and thus ascertaining the average sectional area. The surface velocity may then be taken by noting the time occupied in floating a light object over the selected distance, and as four-fifths of the surface -velocity are about equal to the actual velocity, the yield in cubic feet or gallons per second can be easily calculated. When the water-supply of a town is collected from small streams or gathering -grounds, the rainfall of the catchment basin and its available amount are items which ought to be carefully inquired into. The ratio of the available to the total rainfall, as already shown, is influenced by the nature of the soil, the steepness or flat- ness of the ground, the rapidity of the rainfall, and other circumstances. Professor Rankine has given the follow- ing examples : 152 WATER. Available Rainfall GROUND - divided by Total Rainfall. Steep surfaces of granite, gneiss, and slate, nearly 1 Moorland hilly pastures . . from '8 to "6 Flat cultivated country . . from '5 to -4 Chalk . ... The average annual rainfall in different parts of this country varies from '22 to 140 inches, the least recorded depth being 15 inches. It is greater in mountainous than in flat districts, and on the leeward side of a moun- tain ridge than it is on the side facing the prevailing winds. As regards water-supply, the most important data are the least annual rainfall and the longest period of drought. In selecting drainage areas, it must be borne in mind that the nearer the actual rainfall water is collected the freer it will be from impurities, and that purity of water and fertility of soil are not to be expected together. Water collected from a peaty soil will contain large quan- tities of vegetable matter, while that from a soil well cultivated will be tainted with animal impurities. The purest water, therefore, which can be collected from drainage areas is found in the barren moorland districts of the primary geological formations, or of the sandstone rocks. The channels of the gathering-ground may either be the natural watercourses of the district, or these may be supplemented by adits, closed drains, or open ditches. The latter, however, are objectionable because they form receptacles for vegetable matter, and as the current in them must be necessarily slow, there is considerable loss by evaporation. The position, extent, and dimensions of the adits leading to the reservoir will depend upon the configuration of the district. The reservoir itself is gener- ally a natural hollow, situated in the valley-line of the WATER. 153 catchment basin, and of sufficient elevation to procure a fall, so that the water can be distributed without mechanical means being required to raise it. In this country the storage-room should be large enough to con- tain a four or six months' supply ; and the site which can supply the requisite storage -room with the least embankment, the least amount of puddle, and the least area laid under water, is to be preferred. Upon the strength and stability of the embankment everything depends. It is made watertight by a core of clay puddle, the inner slope being protected from the action of the water by a pitching of dressed stones, and the outer from the effects of the weather by a covering of grass sods. The puddle-core generally amounts to a tenth of the whole embankment. The height of the embankment varies from 3 to 10 feet above the highest water-level, the top being covered with broken stones. No trees or shrubs are allowed to grow upon it, and the greatest care is taken in its construction to prevent animals, such as water-rats, bun-owing into it. Every impounding reservoir, as it is called, is pro- vided with an overflow weir to permit the discharge of the flood supply from the drainage area, and this is often supplemented by a channel termed the lye-wash, which is used to divert the streams supplying the reservoir, so as to prevent fouling of the store-water. The flood-water carried off in this way flows into the natural water- course. In order to remove the sediment which collects in the bottom of the reservoir, there is always a cleansing pipe as well as a discharge pipe, the former being on a level with the lowest point in the reservoir, and discharg- ing into the natural watercourse below the embankment. Both are carried through a culvert in the embankment, which is built of stone or brick, and founded on the 154 WATER. solid rock. The aqueduct or discharge -pipe bends up- wards in the reservoir, and has a series of inlets, the lowest at the lowest working level, and the whole of them guarded against the entrance of small stones, pieces of wood, or other bodies, which would interfere with the action of the valves. The sluices which are required for both pipes are situated in the reservoir, and are worked from the sluice-tower. The aqueduct is that portion of the conduit leading from the reservoir to the distributing conduits. It may be open or close throughout, or partly close and partly open. If close, it generally consists of a train of cast- iron pipes securely jointed, bedded on a firm foundation, and covered to a depth of at least 2 or 3 feet, to preserve them from frost. Sluice stop-cocks are provided in the valleys, for the purpose of scouring out any stones or sediment, and, at intervals not exceeding half a mile, to permit of repairs. Valve-cocks are supplied at all the principal summits, to allow the escape of air. When the aqueduct is partly close and partly open, or if, when close, it cannot withstand the whole pressure when the demand ceases, either a system of weirs is required to discharge the surplus water, or a second store-reservoir is provided, resembling in general plan and construction the impounding reservoir. The distributing conduits also consist of cast-iron pipes, and are coated, like the aqueduct pipes, with pitch, or Dr. Angus Smith's varnish, to preserve them from cor- rosion. The same details with regard to sluice-cocks and stop-cocks are observed in the different bends of the tracks, with this addition, that the dead ends or termina- tions of the branch and main conduits are supplied with scouring valves, through which stones and sediment can be washed. In wide streets, or in streets with much traffic, there is generally a service pipe for each side, in WATER. 155 order that the house-pipes may be as short as possible, and may be accessible without disturbing the traffic. The house service-pipes are usually made of lead, and though they are liable to be acted upon by some waters, the readiness with which they can be adapted to all the bends and curves rendered necessary in carrying the piping to different floors of houses, gives them a preference to all other kinds of metal pipes. The waters which act most on lead are the most highly oxygenated, and those which contain organic matter ; those which act least on it con- tain carbonic acid, calcium carbonate, and calcium phos- phate. Polluted shallow -well waters are especially dangerous in this respect, because they act on it violently and continuously, and hence leaden pump -pipes should never be used. Various means have been proposed to protect the lead from corrosion, such as coating with bitu- minous pitch or with coal tar; but when the quality of the water renders lead pipes objectionable, cast and wrought iron pipes make the best substitutes, or com- posite cylinder pipes. These pipes consist of a separate tube of pure block-tin encased in lead, and the union of the two is so perfect that no amount of torsion will separate them. As the greatest hourly demand for water is about double the average hourly demand, the main conduits supplying a town must have double the discharging capa- city which would be required if the hourly demand were uniform. The additional expense in piping which would be thus entailed is sometimes so great that distributing basins or town-reservoirs are constructed to supply certain districts. To meet all emergencies, tljey are made large enough to contain at least a day's supply, and they must also have a site of sufficient elevation to ensure distribu- tion by hydrostatic pressure. Every such reservoir should be roofed in and ventilated, to protect the water from 156 WATER. frost and heat, and from becoming tainted with aerial impurities. The water thus distributed to the various houses in a district is supplied either on the intermittent or con- stant system. The intermittent system necessitates storage in house cisterns, and is attended by so many disadvantages, that the constant system should always be adopted wherever it can be carried out. The use of cisterns, except on a small scale, for water-closets and boilers, is open to the great objection of the risk of con- tamination of the water, for not only are the cisterns liable to become fouled if not sufficiently protected against the entrance of aerial impurities, but the water is apt to become tainted with sewer-gases. Moreover, in poorer districts, the cisterns are often of a very inferior descrip- tion, are badly situated, and are seldom inspected or cleaned out. To meet this objection, it has been pro- posed to have one large tank for the supply of a group of houses, the tank to be under the immediate inspec- tion of the waterwork officials, and to be filled daily, and the householders to be supplied through small pipes con- stantly charged. It is further urged against the inter- mittent system, that the distribution pipes, being alter- nately wet and dry, are liable to collect dust and the effluvia from sewers or drains. The objections to the constant system, on the other hand, are the great waste when the fittings are imperfect, and an insufficient de- livery when the water-supply is not abundant. _ The diameters of the pipes for constant service should there- fore be carefully adapted to their discharges and to the head of pressure ; the drawing taps ought to be valve- cocks to open and shut with a screw ; and the town should be efficiently provided with distributing basins, so that an extra flow of water in one district would not in- terfere with the requisite supply of other parts. With WATER. 157 proper fittings, strict regulations, and efficient supervision, it is now clearly established that a constant supply re- quires a less amount of water than an uncontrolled inter- mittent supply, so that even on the score of economy the constant system is to be preferred. In order to prevent undue waste, water-meters are sometimes applied to the service-pipe supplying a group of houses, and the landlord charged for the amount used ; but as this plan induces the landlord to enforce a too rigid economy, it is not to be commended. The best water-meters are capable of registering exactly all amounts exceeding a flow of one gallon per hour ; but when the water contains a considerable amount of undissolved im- purities, and is badly filtered, they very soon become clogged up and fail to register anything like the quantity of water which may pass through them. * , The waste-preventer, or small cistern for the supply of water-closets, which has already been alluded to, should at least hold 2 gallons. The smallest waste-preventers hold % of a gallon, but this quantity is insufficient to flush the pan and soil-pipe properly. Another plan for effecting economy in the constant system, proposes that a cistern, large enough to hold a twenty-four hours' supply, be provided for each house, and that the service-pipe shall be of a diameter to deliver the required quantity during that time, and nothing more. Every cistern supplied in this way would become gradu- ally emptied during the day time, and would be refilled during the night ; but the plan is open to the great ob- jection attaching to the intermittent system, and does not sufficiently provide for emergencies. Wherever cisterns are employed, they should be so situated that they can be readiJy cleaned out when neces- sary. The best materials for their construction are slate- slabs well set in cement, or galvanised iron. Leaden 158 WATER. cisterns, unless lined with a coating of pitch, tar, or other preservative substances, are objectionable. All cisterns should be covered in, and protected from heat and frost. No cistern which supplies water for domestic use should be used to directly supply a water-closet ; a waste-pre- venting cistern should always intervene. The inlet to every cistern ought to have a cock, with a float to rise and stop the supply when the cistern is full ; and when the supply is constant, the overflow should be so arranged as to become troublesome if not immediately rectified. An overflow pipe from a cistern should never lead directly into a soil-pipe, sewer, or drain, but should end above ground over a trapped and ventilated grating. If this were always attended to, no sewer-gases could find their way to the cistern through this channel. In addition to the arrangements for domestic supply, outlets or hydrants with valve-cocks are provided on the service-pipes of all large towns, at regular intervals, in case of fire, and for supplying water to flush the gutters and water the streets. In laying down water-pipes and mains, it is of great importance that the separation between them and sewers, drains, or gas pipes should be as wide as possible. Whether the water-supply be on the constant or intermittent sys- tem, the risk of suction of gases or fluids into leaky mains is imminent, though of course much less when the supply is constant. Unfortunately, however, this danger of con- taminating public water-supplies has hitherto not been appreciated, and indeed in many towns, as for example in Croydon, it has been enhanced by arrangements for flush- ing sewers directly from the mains. (See Mr. Simon's Reports, New Series, No. VII.) Another danger to a public water-supply is the direct connection of water-drains with closet-pans. In Warwick and Eugby I found that nearly one-fourth of the closets WATER. 159 were flushed directly from the main by means of stool- cocks, and on my recommendation the whole of them were disconnected. SECTION IV. PURIFICATION OF WATER. On an extensive scale the process of purification is carried on by means of filtration, the water being received into large filter-beds previous to its distribution. A filter- bed may be described as a tank or reservoir several feet in depth, with paved bottom, on which are laid a series of open-jointed or perforated tubular drains leading into a central culvert. The drains are covered with a layer of gravel about 3 feet deep, over which is spread a layer of sand about 2 feet deep. The layer of gravel is coarse at the bottom, becoming gradually finer towards its upper surface, and the same relative gradation, as regards coarse- ness and fineness, is observed with regard to the sand. The water is delivered uniformly and slowly, and in order that the filtering process may not be carried on hurriedly, the pressure is always kept low, the depth of water being seldom above 2 feet, and in some cases only 1 foot. The speed of vertical descent should not be much above 6 inches per hour, nor should the rate of filtration much exceed 700 gallons per square yard of filter-bed in the 24 hours, although some water companies filter at a much more rapid rate than this. In large works there are always several filter-beds, to allow of some being cleansed while the others are in use. The sediment deposited on the surface of the sand requires to be scraped off at intervals, and at each cleansing operation about half an inch of sand is also removed. A fresh supply of sand is added when the depth of the layer is reduced to an extent which threatens to impair the efficiency of the filter. It appears that proper filtration, carried on according to this 160 WATEE. plan, removes suspended impurities, and a certain amount of dissolved mineral substances, but whether dissolved organic matters are destroyed, or oxidised to any consider- able extent, seems doubtful. Small filters for domestic use may be placed in the cistern, in the course of the delivery pipe, or they may be filled by hand. As filtering media various substances are used, such as animal or vegetable charcoal, a mixture of fine silica and charcoal, magnetic carbide of iron, sponges, wool, etc. According to Dr. Parkes, the best filters are made either of animal charcoal or magnetic carbide of iron. They are capable of removing almost all the suspended matters, and at least 40 per cent of dissolved organic impurities, together with a considerable amount of salts, such as calcium carbonate and sodium chloride. Indeed, the experiments of Mr. Wanklyn with the siiicated carbon-filter prove that, by repeated filtration, river water containing a considerable amount of free and albuminoid ammonia may be made as pure as deep spring water. Of filtering media, animal charcoal, properly washed, is now admitted to be in every way the most efficient, but it should be frequently renewed. It exerts a chemical as well as mechanical action on organic impurities, and Dr. Frankland is so convinced of its value as a filtering agent that he recommends its employment on a large scale for the purification of town supplies, in spite of the cost which would be entailed. Professor Bischof has also discovered that spongy iron possesses remarkable purify- ing properties, which have been fully confirmed by the experiments of the Eivers Pollution Commissioners, and it may here be stated that the spongy iron filter received the medal of the Sanitary Institute a few years ago for its general excellence. Carferal is another substance which has lately been introduced, and is highly spoken of as a filtering medium. It resembles charcoal in ap- WATER. 161 pearance, and consists of a mixture of charcoal, iron, and clay. Amongst other filters which have been commended for their efficiency, may be mentioned the cistern filter of the Water Purifying Company, London ; Lipscombe's Self-Cleaning Charcoal Filter; the Patent Carbon Block Filter, manufactured by Atkins and Co., London ; the Carbon Cistern Filter, planned by Mr. Finch of the Hoi- born Sanitary Works ; and the various filters devised by Halliday and ^Co. of Manchester, and Doulton and Co. of London. All of these contain animal charcoal as the filter- ing medium, and can be applied to any kind of house cistern. The filtering block of the Silicated Carbon Company consists of 75 per cent of charcoal and 22 of silica, with a little iron oxide and alumina. It is cemented into a vessel which it divides into two chambers, the one containing the filtered and the other the unfiltered water. This filter is found to work very efficiently, and with a little care retains its properties for a long time. The filtering material of the Magnetic Carbide Filter is pre- pared by heating haematite with sawdust, and has all along been highly commended. The Patent Moulded Carbon Filter makes an elegant article for the sideboard. It consists of two glass vessels, the upper containing the filter-block, and the lower, which can be used as a water bottle, the filtered water. Tap-filters, suited for a high or low pressure, can be fitted to the pipes themselves. They contain charcoal or silicated carbon, and would seem to act very well. Mr. Bailey Den ton's " Self- Supply ing Aerated Filter " is placed beneath the house cistern, and by a simple arrangement of valve-cocks as much water is supplied to the cistern as is removed from the filter every time water is drawn off. Amongst other domestic filters may be mentioned Dr. Bond's Patent Floating Feed Filter and Floating Syphon Filter, Dr. Bernay's Man- II 162 WATER. ganous Carbon Filter, and M. Maignen's " Filtre. Rapide," in which asbestos cloth and a substance called carbo- calcis are employed as the filtering media. A charcoal filter has been introduced by Lieut.-Col. Crease, of the Royal Marine Artillery, which, for sim- plicity of construction, adaptability to different kinds of water and rates of supply, and for efficiency, deserves special notice. It is now largely used in the Navy, and is specially suited for large buildings, such as asylums, workhouses, etc. The tank is made of iron, lined with cement, and the whole of the apparatus can be readily unscrewed, taken to pieces, and cleaned out when neces- sary, the joints being made water-tight by gutta-percha bands. Pocket Syphon Filters are made of hollow blocks of charcoal, with a tube passing into the cavity, into which the water filters through the charcoal. All filters after a time become clogged up, and have therefore to be taken to pieces and thoroughly cleansed ; or, if this cannot be easily done, they may be purified by passing through them a solution of potassium perman- ganate or Condy's fluid, with the addition of a few drops of strong sulphuric acid, and afterwards two or three gallons of pure or distilled water, acidulated with hydro- chloric acid. The charcoal in a filter may also be purified by exposing it for some time to the sun and air, or by heating it in an oven or furnace. In the spongy iron filter the filtering medium has to be renewed from time to time. The purification of water without filtration is not carried on in this country on the large scale except by Dr. Clark's process. This consists in adding a certain amount of lime water to a water which contains calcium carbonate rendered soluble by the presence of carbonic acid. Spring waters in the chalk districts are all more or less " hard," and many of them contain such a large WATER. 163 amount of calcium carbonate in solution as to be unfit for washing purposes. Such a water, when it is to be rendered " soft " by Clark's process, is let into a tank or reservoir, where it is mixed with a proper proportion of lime water and allowed to settle, the whole of the calcium being precipitated as calcium carbonate. A perfectly clear and wholesome water is thus obtained, well suited for domestic purposes. Calcium carbo- nate may also be removed by boiling, in which case it is deposited as an incrustation on the inner surface of the kettle or boiler. What is known as the " Porter- Clark Process" is a modification of Clark's process, which, at the same time, provides for very efficient filtration. Aluminous salts have long been used in Eastern countries to purify water, and are found to be very effica- cious in removing suspended matters, whether organic or mineral. Organic matters in solution are best treated with potassium permanganate or Condy's red fluid. It readily removes any offensive odour arising from water kept in casks, and oxidises at least a portion of the organic impurities which may be present ; but as albumen is only slightly affected by it without the aid of heat, it cannot be regarded as a reliable purifier of water tainted with animal impurities. Suspicious waters should always be boiled before being used. Among other purifying agents may be mentioned, distillation, the exposure of water in minute divided currents to the air, the immersion of pieces of charcoal or of iron wire, and the effects of plants and fish. In store reservoirs, the presence of a moderate quantity of living plants exerts a decidedly purifying influence, while the destruction of fish has been followed by an excessive multiplication of the small crustacean animals on which the fish had lived, thereby rendering the water nauseous 164 WATER. and impure. The remedy was found in re-stocking the reservoir with fish. (Eankine.) SECTION V. SOURCES OF POLLUTION. Although reference has already been made in the preceding remarks to various ways in which drinking water becomes polluted, it will be expedient to consider this important part of the subject somewhat more fully in detail ; and first with regard to the water-supply of rural and small urban districts. Estimating the town population of Great Britain at about fifteen millions, the Kivers Pollution Commissioners observe that " the remaining twelve millions of country population derive their water almost exclusively from shallow wells, and these are, so far as our experience extends, almost always horribly polluted by sewage, and by animal matters of the most disgusting origin. The common practice in villages, and even in many small towns, is to dispose of the sewage and to provide for the water supply of each cottage, or pair of cottages, upon the premises. In the little yard or garden attached to each tenement, or pair of tenements, two holes are dug in the porous soil ; into one' of these, usually the shallower of the two, all the filthy liquids of 'the house are dis- charged ; from the other, which is sunk below the water line of the porous stratum, the water for drinking and other domestic uses is pumped. These two holes are not unfrequently within twelve feet of each other, and sometimes even closer. The contents of the filth hole or cesspool gradually soak away through the surrounding soil, and mingle with the water below. As the contents of the water hole or well are pumped out, they are immediately replenished from the surrounding disgusting mixture, and it is not therefore very surprising to be WATER. 165 assured that such a well does not become dry even in summer. Unfortunately, excrementitious liquids, especi- ally after they have soaked through a few feet of porous soil, do jnot impair the palatability of the water; and this polluted liquid is consumed from year to year with- out a suspicion of its character, until the cesspool and well receive infected sewage, and then an outbreak of epidemic disease compels attention to the polluted water. Indeed, our acquaintance with a very large proportion of this class of potable waters has been made in consequence of the occurrence of severe outbreaks of typhoid fever amongst the persons using them." (See Sixth Report.) Although it can scarcely be said that this description applies to rural districts generally, there can be no doubt that it correctly represents the condition of the water- supply of a vast number of villages and scattered country houses. Cesspools, cesspits, or drains, in close proximity to wells, are a fruitful source of mischief; and so also are midden-heaps or deep ashpits connected with privies, and the huge manure-heaps which are allowed to accumu- late in farmyards. All such collections of liquid or solid filth should be regarded as dangerous nuisances, and should either be done away with altogether, or such adequate precautions taken as will obviate the risk of soakage into the well. The substitution of a dry system of conservancy and the use of pails or boxes for the cess- pool, common privy, and cesspit, together with better scavenging, would lessen to a very large extent the dangers of well-pollution in country districts; but in crowded localities the soil becomes so saturated with filth of all kinds that surface wells are never safe. All pump wells should be clay-puddled to a depth of eight or ten feet, to keep out surface impurities ; and instead of draw wells or shallow open dip wells, which are especially liable to pollution, either proper pump wells should be 166 WATER. provided, or, where the nature of the subsoil is suitable, Norton's tube wells would be found to possess many advantages. Surface wells near graveyards are very often found to be polluted; But even when there is no drain or cesspool near, a well frequently becomes polluted because it is never cleaned out, and for my own part I regard this periodic cleansing of wells so necessary that I think every pump well should be provided with a manhole and be cleaned out at stated times. In towns or large villages provided with a public water-supply, the closing of all surface wells, whether public or private, should be rendered com- pulsory ; for, with drains ramifying in every direction, it may be taken for granted that they are either polluted, or are at all events constantly liable to pollution. With regard to public supplies, it may be stated, generally, that water may become polluted either at its source, in the course of distribution, or through defects connected with its storage. Any supply which is taken from a river polluted by the sewage of towns up-stream must be carefully filtered, and even then it can only be regarded as a suspicious water. Deep wells or springs, on the other hand, may become polluted by the entrance of surface impurities, or by the access of polluted water through open fissures in the rock. But perhaps the most frequent and insidious sources of pollution to which public supplies are exposed, are those dependent upon the arrangements for distribution and storage. It has already been pointed out that, with an intermittent supply, the mains must necessarily become full of air when the water is turned off, and if at all leaky, as they very often are, they may become charged with liquid as well as aerial impurities. Moreover, when water-closets are served direct from the mains by mere taps or stopcocks, there is always the danger of liquid filth being sucked WATER. 1 6 *7 into them whenever a closet-pipe becomes choked up, and the pan becomes full. The following experiment will illustrate how readily such pollution may occur: In the report on Croydon, already referred to, Dr. Buchanan states that he had a common house tap connected with a pan containing solution of burnt sugar sufficient to colour some thousand gallons of water, and that .in the ordinary night -intermission of supply, the whole of this was straightway sucked into the pipes, and except from one neighbour, was no more heard of. He also adds that there is an instance on record of bloody water coming from the main tap of a house situated next to a slaughter- house. Then, too, connected with this system of inter- mittent supply, there are all the risks of contamination attaching to cisternage, or storage in pails, butts, or other receptacles. If the same cistern is used to supply the house and the water-closet as well, sewer -gases from the closet have access to the surface of the water in the cistern; or should the overflow pipe from the house cistern discharge direct into a sewer or drain, there is of course the same danger. Apart also from the risk of lead-pollution from leaden cisterns, the water stored in a cistern may eventually become unfit for use, because the cistern is seldom or never cleaned out. But even with a constant supply there appear to be certain dangers depending upon possible in-currents from leaky mains, especially when these are in juxtaposition to sewers or drains which have hitherto escaped the notice of engineers. The physical conditions under which such in-currents may take place have been in- vestigated to a certain extent by Dr. Buchanan, and I quote his results here, in order that others may be induced to make experiments in the same direction. In a note appended to the Croydon report he gives the following summary of results : " I find (1) the lateral in-current 168 WATER. is freely produced when the water-pipe is descending, and when the pipe beyond the hole is unobstructed ; (2) if the force of water-flow in a descending pipe be moderate, a moderate degree of obstruction beyond the hole does not prevent the in-current ; (3) in horizontal pipes of uniform calibre, when the flow is strong, or the pipe beyond the hole is long, or when the end of the pipe is at all turned upwards, the in-current does not take place, but (4) momentary interference with flow a tergo, or momentary reduction of obstruction a fronte, allows of a momentary in-current through the hole ; (5) in-current through a lateral hole takes place with incomparably greater ease when the hole is made at a point of con- striction of the water-pipe." It has further to be observed that water mains, if not sufficiently protected against corrosion, may render the water turbid, owing to rusting of the iron ; that the tow or gaskin employed to caulk joints may taint the water for a long period if the main is several miles in length ; and that leaden pipes, especially when first laid down, may become a source of danger if the water is soft. With regard to the general effects of drinking impure water, and particular outbreaks of disease depending upon ascertained sources of pollution, see Chapter VIII. WATER ANALYSIS. 169 CHAPTEE VII. WATER ANALYSIS. SECTION I. COLLECTION OF SAMPLES. IN collecting water for analytical purposes, and parti- cularly when it is intended to submit samples to a quantitative analysis, the following directions should be observed : An ordinary glass-stoppered Winchester quart bottle will answer very well for the conveyance of the water. It should be cleaned out with strong sulphuric acid, then rinsed with ordinary good water until the rinsings are no longer acid, and finally washed out with some of the water to be examined. The bottle should be filled almost up to the neck, stoppered, and the stopper covered over with a piece of clean calico, wash leather, or gutta percha tissue, tied, and sealed. No luting should be used except sealing-wax, and even that should be dis- pensed with if possible. If the water contains organic matter, it should be examined at least within forty-eight hours after being collected. In collecting pond or lake water the bottle should be plunged into the water as far. as possible from the bank, with the mouth well under the surface, so as to avoid the scum, care being taken, at the same time, that the mud at the bottom is not disturbed. If the sample is taken from a town supply, it should, if possible, be collected direct from the mains, or from the water-jets at the cab- 1 7 WATER ANALYSIS. stands or public fountains, in which case the water should be allowed to flow for some time previous to filling the bottle. If taken from a house service -tap, the water should also be allowed to flow for some time before col- lecting. With regard to river water, it is recommended to select the middle of the stream, to avoid the outlets of sewers and feeders, and to note whether there has been previously a heavy fall of rain or a long drought. When a sample is required from, the source of a spring, it is sometimes necessary to dig a small excavation and allow all sediment to subside before the sample is taken. Well- water should of course be drawn direct from the well. Different methods of examination require different quantities ; for Mr. Wanklyn's method one Winchester quart will be quite sufficient, but for a complete investiga- tion some analysts require about a gallon. If a Winchester quart cannot readily be procured, a clear glass wine bottle will answer very well, but care must be taken to have it thoroughly clean, and the cork should be clean and new, and fit well. The medical officer of health will find it very con- venient to have a basket containing two or more clear glass - stoppered bottles placed under the charge of the sanitary inspector of the district. The basket should be provided with a padlock fitted with two keys, one of which should be in the possession of the medical officer of health and the other retained by the inspector. Before forward- ing the bottles, the inspector should affix a label to each, containing the date and a distinctive number, or certain particulars with regard to- the source of the water and why it is suspected. For ordinary analysis pint stoppered bottles will be found to be large enough, because, should a greater quantity be required at any time, two bottles can be used instead of one. WATER ANALYSIS. SECTION II. PHYSICAL EXAMINATION. A portion of the sample collected should be poured, after shaking the bottle, into a good-sized clear glass flask. If the flask is then held in front of a dark-coloured surface, with a good light falling on the side or from above, any suspended impurities will become visible, but care should be taken to discriminate between them and air-bubbles. Colour and turbidity are best ascertained by pouring the water into a tall vessel of colourless glass, and placing it upon a porcelain slab or piece of white paper. Another glass of the same dimensions, filled with distilled water, should be placed by its side for comparison. Both samples are then looked through from above, and the difference between them noted. If organic matter is pre- sent, the water has usually a tinge of yellow, green, or blue, but mineral substances may give similar indications. Clay, peat, and other harmless contaminations impart a brownish tint. If the turbidity is considerable, or if the water is very dark in colour, it may be pronounced unfit for use, although filtration may render it perfectly wholesome. To observe the smell of the water, a portion of it should be poured into a wide-mouthed flask, making it about one-third full, and then shaking it well. If the smell is unpleasant, the water is unfit to drink. Should no smell be detected, the flask should be heated, and the water again shaken, and if there is still no smell a little caustic potash should be added to the warm water. Any unpleasant odour which may now be given off indicates with tolerable certainty that the water contains organic impurities in considerable quantity. The occurrence of a precipitate on the addition of the caustic potash will at the same time indicate hardness. 172 WATER ANALYSIS. With regard to taste, it is sufficient to say that a badly- tasting water should be condemned for drinking purposes. Many waters, however, which are largely impregnated with dissolved animal impurities may be quite palatable. Altogether, the physical examination of water is of a negative character ; and although it may impart some useful information, it cannot be relied upon in arriving at a sound conclusion as regards the good or bad qualities of any given sample. SECTION III. MICROSCOPICAL EXAMINATION. In order to collect the sediment the water should be poured into a large depositing-glass, and allowed to stand for 12 or 24 hours. Particles of sand are recognised by their angular shapes, and by their not being affected by acids. Particles of clay and marl are amorphous, and are also unaffected by acids. Particles of chalk are amorphous, and are readily dissolved by acids. Dead vegetable matter, such as woody fibre and portions of leaves, and living vege- table matter, consisting of confervoid growths, may all be detected in water which cannot be pronounced unwhole- some. So also may diatomacece, infusoria, and entomostraca. Microscopical examination, therefore, is only valuable for practical purposes, in so far as it indicates the various components of the suspended matters ; it gives no direct information concerning the presence of dissolved organic impurities. There is no doubt, however, that it presents a wide and interesting field for research, and in this respect the writings of Drs. Burdon Sanderson, Cohn, and Macdonald of Netley, are extremely valuable. Eeference should also be made to Koch's gelatine process, as recently explained by Dr. Angus Smith, which appears to be full of promise, and to indicate a new departure in water- analysis. (See Sanitary fiecord, 1883.) WATER ANALYSIS. 173 SECTION IV. CHEMICAL EXAMINATION. This may be either qualitative or quantitative. For ordinary purposes, as, for example, in the discharge of a medical officer of health's duties in rural districts, a quali- tative examination, if judiciously conducted, will be found to be quite sufficient to enable him to give a reliable opinion as to whether a water is fit for use or not in the great majority of instances, provided the water is not specifically polluted. But, in all cases in which qualita- tive tests indicate that a water is doubtful or suspicious, and in cases which are likely to lead to magisterial pro- ceedings, it is necessary to submit the sample to a quan- titative analysis more or less complete. A quantitative analysis is also required in the examination of public supplies, and in the case of any proposed new public supply it should be thorough in all its details. But the main object which the sanitarian has in view is to determine whether or not any given water is dan- gerously contaminated with organic matter, and this, as I have already said, may be ascertained in the great ma- jority of instances by a qualitative examination. After noting the various indications obtained from the physical i-xamination previously described, and taking care that all test-tubes, test -glasses, measures, and the like, are thoroughly clean and conveniently arranged, the qualita- tive testing of one or more samples may be readily con- d-.cted as follows: 1. Qualitative Examination. (1.) Ammonia. Fill an ordinary test-tube of about 1 oz. in capacity nearly full with the water to be examined, and add 3 or 4 minims of the Nessler re- 174 WATER ANALYSIS. agent. If a yellow or brown colour, or a brownish pre- cipitate, be produced, the water contains ammoniacal salts. As a rule, this should be regarded as a very suspicious circumstance, and should the coloration be well marked, it is almost sufficient of itself to condemn the water for drinking purposes. A milky or curdy-looking precipitate will also indicate that the water is hard. If the precipi- tate is excessive, it masks, to a certain extent, the colour indicative of the test, in which case it is advisable to take a fresh sample in another test-tube, add a few drops of a strong solution of caustic potash, and after the precipitate which is thus formed subsides, add the Nessler re-agent. (2.) Nitrites. Fill an average-sized test-glass about three parts full of the water to be examined, then add 5 minims of pure sulphuric acid and 5 minims of a solution of potassium iodide (5 grs. to 1 oz. distilled water), and afterwards pour in a small quantity of freshly-prepared starch solution. The solution is readily prepared by boil- ing a small quantity of starch powder in a vessel contain- ing distilled water. A blue tint indicates nitrites, and should the colour be at all deep the water is scarcely fit to drink. As iodide of potassium sometimes contains iodate, it is always advisable to make a comparative ex- periment either with distilled water or with a water which is known not to contain nitrites. Instead of the sulphuric acid, acetic acid may be used, and the starch paste, potas- sium iodide, and acid, may be mixed before adding the solution to the water. (3.) Nitrates. The readiest method of testing for nitrates is that known as Horsley's test, of which the fol- lowing modification has been proposed by Dr. Bond of Gloucester : Put 2 minims of pure sulphuric acid into a very small test-tube, then add 10 minims of the water to be examined, and afterwards drop in carefully 1 drop of a solution of pyro-gallic acid (10 grs. to 1 oz. distilled WATER ANALYSIS. 1*75 water acidulated with 2 drops of sulphuric acid). A pink zone, or sometimes a delicate blue zone changing into a dark amethyst tint, and from that into a brown tint, indi- cates nitrates. When shaken up, the greater part of this coloration may disappear for a time, but it gradually returns, and after the mixture has stood for a few hours a permanent tint is developed. The detection of nitrates in a water derived from a deep well is no evidence of sewage contamination, because, as in the chalk formation, they may be derived from the strata through which the water passes, but in surface or shallow well waters their presence may fairly be regarded as a suspicious circumstance. (4.) Chlorides. The amount of chlorine in water can be determined so quickly by a simple volumetric method, which will be subsequently described, that those who are provided with the test-solution of nitrate of silver should always adopt this method; but to those who have not this test -solution the following method is recommended: Acidulate a little of the water in a test-glass with a few drops of dilute nitric acid, and add in excess a solution of nitrate of silver. Four grains per gallon of sodium chloride give a turbidity; 10 grains a slight precipitate; and 20 grains a considerable precipitate, soluble in ammonia. A good water should only yield a slight haziness. If there is a distinct precipitate, it shows that the water is derived from a formation rich in salt, such as the new red sand- stone, that it is brackish if on the sea- coast, or that it has been contaminated with sewage. In the first two cases there will be a large amount of mineral solids, and there- fore, in the case of a soft water, any excess of chlorides would point to sewage contamination. On the other hand, it is important to note that the absence of chlorides from a sample of water renders it very probable that it is free from sewage contamination. 176 WATER ANALYSIS. (5.) Lead and Iron. Boil between 3 and 4 oz. of the water acidulated with a few drops of sulphuric acid, and afterwards add sulphuretted hydrogen water. If a brown or blackish coloration is produced, the presence of lead may be inferred. If no colour can be detected, add a little potash or ammonia, and if this produces a blackish precipitate, iron is almost certain to be present. Small traces of iron in a water cannot be considered injurious, but the presence of lead is sufficient to condemn the water as unfit for use. (6.) Organic Matter. Although the permanganate of potash test has of late years fallen into disfavour with many analysts on account of its indefinitiveness, I am still of opinion that it may be employed with considerable advantage in the qualitative examination of surface- well waters, and particularly in localities where salts of iron are not usually found. The following is a convenient method of applying the test : Fill a tall colourless glass vessel or test-tube nearly full with the water to be exam- ined, and add as much solution of potassium permanganate (2 grs. to 4 oz. distilled water) as will impart a distinct pink tinge after stirring with a glass rod. Then fill another glass cylinder or test-tube of the same size with distilled water, and add the same quantity of perman- ganate solution. Place the two glasses side by side on a white sheet of paper or porcelain slab, and note any differ- ences between the two tints which may speedily or sub- sequently take place. If decoloration takes place rapidly, or sets in -gradually, it shows that the water contains oxidisable organic matter, iron, nitrites, or sulphuretted hydrogen. The last of these is rarely found, and would be distinguished by the smell, while the presence of iron or nitrites can be ascertained by tests already described. In the absence of these three any rapid decoloration indi- cates that the organic matter is of animal origin, whereas WATER ANALYSIS. 1 slower changes indicate that vegetable matter is present. With these limitations, and with a general knowledge of the geological characteristics of the well-waters of a dis- trict, the test may be advantageously employed as a con- firmatory test, though it cannot always be relied on when it gives negative results. By a judicious application of some or all of these tests the medical officer of health can examine several samples of water in a comparatively short space of time ; but, in order to conduct the examination systematically, he ought to arrange the test tubes or glasses in separate sets, and number them according to the samples. These, it is presumed, are all derived from surface or shallow well waters, and the 'following indications will enable him to decide as to whether the water is fit for use or not, or whether it is of doubtful purity, in which case it should be submitted to a quantitative analysis : If the water contains a considerable amount of sedi- ment, and is found when decanted off or filtered to show little or no traces of ammonia, nitrates, or chlorides, it shows that it is fit for use, but the well requires cleaning out ; or, should the well be a tube well, that it ought to be filtered. If the sediment is flocculent and dirty-looking, it will generally be found that the water is polluted in other respects, and an order should be given that the well should be opened, examined, and cleaned out, and any ascertained source of pollution removed. In towns or villages where there is a public water-supply, and the premises are within easy reach of a water-main, there should be no hesitation in requiring the well to be closed ; or if the ground is so saturated with filth that it is hope- less to expect that any alterations can ensure subsequent safety, an order to close the well should still be insisted on. But supposing the water is tolerably clear, or quite clear, what are the inferences to be drawn from the quali- 178 WATER ANALYSIS. tative examination ? If there is distinct coloration on the addition of the Nessler re-agent, but very little precipitate, and with no distinct indications of either nitrites, nitrates, or chlorides, it shows that the water is a soft water and fit for use, and that the ammonia is either derived from rain water or is probably of vegetable origin. If ammonia, nitrites, and chlorides in excess are all present, the water is polluted and unfit for use. A water with no great excess of chlorides, and which yields a large flocculent precipitate on the addition of the Nessler re-agent, but does not become tinted, and gives no indication of the presence of nitrites, nitrates, or organic matter, is a hard water, but otherwise fit for use. Should a water contain nitrates and traces of nitrites, but give no distinct indica- tion of ammonia or chlorides, it may be considered fit for use. If nitrites and chlorides are both present in any excess, the water should be regarded as a very suspicious water, and be submitted to a more careful examination, even though the Nessler re-agent should produce no dis- tinct coloration. But it should always be remembered that chemical analysis, however complete, can only indicate danger when palpably present, but it is powerless to indicate any standard of safety when a water becomes specifically polluted. In giving instructions as to what action should be taken when a sample of well-water is found to be polluted, it is always advisable, when there is no public supply within reach, to recommend that the well should be opened and examined. The pollution may arise from want of cleansing, or from leakage from a drain, cesspool, or farmyard, and it will depend upon the special circum- stances of the case as to whether cleansing and removal of the source of pollution will suffice, or whether the well should be closed altogether, and a new one sunk in some other suitable place where there is no risk of pollution. WATER ANALYSIS. 1*79 It is evident therefore that detailed information with regard to the situation and surroundings of a polluted well is of very material service in advising as to what particu- lar steps should be taken ; but, so far as the water itself is concerned, the medical officer of health need only report that it is contaminated and unfit for use. Should his recommendations, when notified in the regular way by the sanitary inspector, not be complied with, it may become necessary to submit the water in question to a quantita- tive analysis, in order to obtain a magistrate's order to cleanse, repair, or close the well, as the case may be. 2. Quantitative Analysis. With the exception of proposed new public supplies, which should in all cases be submitted to a very minute analysis, the only points which require determination in an ordinary quantitative analysis are the total solids, the hardness, the chlorides, and the organic matter as repre- sented by the free and albuminoid ammonia. (1.) Total Solids. The amount of total solids is ascertained by evaporating a known portion of the water to be examined to dryness. Into a platinum dish which has been carefully cleaned, dried, and weighed, pour 70 cubic centimetres of the sample of water ; place the dish in the water or steam -bath, and evaporate to dryness, then wipe the dish externally, and weigh. The difference between the two weighings gives the weight of the residue yielded by 70 cubic centimetres of water. Seventy c. c. are taken, because each milligramme of residue counts for one grain of total residue in a gallon of water, inasmuch as a gallon of water weighs 70,000 grains, and 70 c. c. weigh 70,000 milligrammes. If the operator has a very delicate balance, and has had. some experience in chemical manipulation, 25 c. c. 180 WATER ANALYSIS. of the water to be examined will usually be found suffi- cient, but in that case the result in milligrammes must be multiplied by 2 '8 (4 X *7) in order to obtain the total amount of residue in grains per gallon. Thus, to take the following example : Weight of dish . . . 24 -286 grammes. dish and residue . 24*295 ,, Therefore weight of residue = '009 ,, But "009 grammes are 9 milligrammes, and multiplying this number by 2*8 gives 2 5 '2 grains as the amount of solid residue in a gallon of the water examined. If 1 c. c. are taken, the multiple will of course be *7. The times occupied in the evaporation average about two hours for the 100 c. c., an hour and a quarter for the 70 c. c., and about half an hour when only 25 c. c. are evaporated. In drying the residue, the dish should be put into a hot- air bath, then allowed to cool, and weighed promptly afterwards to avoid deliquescence of the salts. A very cheap and efficient steam -bath can be made from a pint oil -can by fitting it with a cork which is perforated to admit the stem of an ordinary glass funnel. The can is partly filled with water, and fixed on a retort stand, and the platinum dish is placed in the mouth of the funnel with a piece of folded paper between to permit the escape of the steam. The total solid residue consists for the most part of mineral matter, and in many waters this is composed chiefly of carbonate of lime. It is difficult to fix the maximum amount of permissible solid residue in drinking water. In public supplies it certainly ought not, if pos- sible, to exceed 30 grains per gallon, but many usable well-waters are found to contain double this amount. The following are examples of the amount of solids in different waters : WATEE ANALYSIS. 181 Grains per Gallon. Loch Katrine . . . . . 2 '30 Bala Lake 3'18 London Thames Companies ... 21 *66 Rochdale Spring ....'. 25 '93 Norwich Artesian well . . . . 26 70 If a complete quantitative analysis of the saline con- stituents is required, a much larger quantity of water must be evaporated, but the presence and amount of the more important constituents may be approximately determined as follows : a. (Lime.) Pour a little of the water into a test- glass, and add a solution of ammonium oxalate. Six grains of lime per gallon will yield a slight turbidity ; 1 6 grains a distinct precipitate ; and 3 grains a large precipitate, soluble in nitric acid. 1. (Magnesia.) In a good water there should only be a slight haziness, or none at all, on the addition of ammonia. c. (Sulphates.) Acidulate with a few drops of hydro- chloric acid and add a solution of barium nitrate. A good water should not give more than a slight haziness. It is seldom, however, that these subsidiary tests are required. A more important indication is obtained by incinerating the residue over a flame, when, if blackening occurs, the presence of organic impurities may be inferred, and should a bad smell be given off at the same time, it is almost certain to be derived from impurities of animal origin. (2.) Hardness. It has already been pointed out that a water is hard or soft according to the amount of solid , ( residue which it contains. Thus a water which contains only three to four grains of residue, such as the Loch Katrine water, is an exceedingly soft water ; a water containing eight to ten grains is a moderately soft water; while those which contain twenty grains and upwards are 182 WATER ANALYSIS. hard waters. For purely sanitary purposes, therefore, the determination of the hardness is seldom required, if the total solid residue has been ascertained. The hardness of a water is due to the presence of earthy salts, generally carbonate of lime and sulphate of lime and magnesia. The former is deposited on boiling, and is represented by what is called the removable hardness, while the latter, inasmuch as it is not affected by boiling, is called the permanent hardness. The rationale of the process, as . first explained by the late Professor Clark, will be under- * stood when it is remembered that if an alkaline oleate, such as soap, is mixed with pure water, a lather is formed almost immediately; but if salts of lime, magnesia, baryta, iron, or alumina are present, oleates of jthese bases are formed, and no lather is given until_the earthy bases are thrown down. As the soap will combine in equivalent proportions with these bases, it is only necessary to make the solution of soap of known strength by standardising it with a known quantity, say of chloride of calcium, to be able to determine the amount of lime or its equivalent of other salts in the water so much soap required before a lather is produced represents so many degrees of hard- ness. The standard solutions are prepared and deter- mined according to the following method, proposed by Messrs. Wanklyn and Chapman : Make a solution of pure calcium chloride of I'llO grammes to the litre of distilled water. Each cubic centimetre of this solution contains an amount of calcium chloride equal to one milligramme of carbonate of lime. The standard soap test is made by pounding together two parts of lead plaister with one of carbonate of potash, exhausting re- peatedly with alcohol at 90 per cent, and using about thirty times as much alcohol as lead plaister. This solution is allowed to stand for some time, and is then filtered, and afterwards diluted with its own volume of WATER ANALYSIS. 183 water. In order to standardise it 10 c. c. are taken and put into a bottle with 70 c. c. of pure water ; the chloride of calcium solution is now added until frothing stops, care being taken to shake properly; and from this trial experiment it is easy to calculate how much dilution of the soap solution is requisite in order to make 1*7 c. c. of the soap-test use up 16 c. c. of the chloride of calcium solution. The dilution should be made with alcohol of 50 per cent, and the soap test carefully verified after it has been made up. This is done by adding 16 c. c. of the standard solution of calcium chloride to 54 c. c. of distilled water, thus making a solution of 70 c. c., which should exactly be neutralised by 17 c. c. of the standard soap-test. A much easier method of making the soap test, and one which gives fairly accurate results, is to dissolve ten grammes of green Castile soap in a litre of weak alcohol of about 3 5 per cent. One cubic centimetre of this solution also precipitates one milligramme of carbonate of lime. Either solution, therefore, may be used, and the mode of employing the test is as follows : Into a clear glass-stoppered bottle, capable of holding about 250 c. c. put 70 c. c. of the water. Add slowly from a burette the standard soap solution, and shake well until a persistent lather is formed, noting accurately the amount of solution used. Each c. c. of the solution con- sumed indicates one grain of carbonate of lime or its equivalent in a gallon of water. If, after adding 17 c. c. of the solution, no lather is formed, add 70*c. c. of dis- tilled water and mix, and continue the addition of the soap solution. Should no lather be formed until other 17 c. c. are consumed, other 70 c. c. of distilled water must be added, but in making the calculation for hard- ness, 1 must be deducted from the number of c. c. of soap solution used for each 70 c. c. of water which have been 184 WATER ANALYSIS. added, and this deduction is necessary because 70 c. c. of distilled water would themselves neutralise about 1 c. c. of soap test. Suppose, for example, that 18 c. c. of soap solution have been required, then 1 must be deducted from the 70 c. c. of distilled water which were added, and the hardness of the sample in question is put down as 1 7 degrees. In other words, the total soap-destroying power of the water is equivalent to 17 grains of carbonate of lime per gallon. The permanent hardness is obtained by boiling 70 c. c. of the water for about an hour, and making up the loss by evaporation with distilled water. During boiling, the bicarbonate of lime is decomposed and the carbonate deposited, and thus the water becomes softer. After allowing to cool and filtering, the perma- nent hardness is determined in the same way as the total hardness, and the difference between these two, as already stated, is the removable hardness. According to Wanklyn's method, the degrees of hard- ness represent " the potential carbonate of lime," and in translating them into Clark's degrees, it is necessary to deduct 1. Thus, in the above example, the degrees of hardness, according to Clark's standard, would be 16. Altogether, the importance of this test has been greatly over-estimated, and it is seldom that the medical officer of health will deem it necessary to employ it. (3.) Chlorides. The estimation of chlorine as chlorides in water can be readily determined volunietrically by means of chromate of potash and a standard solution of nitrate of silver. This solution is prepared by dissolving 4* 7 9 grammes of dry nitrate of silver in a litre of distilled water. As chromate of silver is soluble in acids, it is necessary that the nitrate of silver used should be neutral. Each c. c. of this solution precipitates 1 milligramme of chlorine. 70 c. c. of the water to be examined are put into a beaker or evaporating dish, and a small crystal WATER ANALYSIS. 185 of pure chromate of potash, or a few drops of a strong solution of this salt added, sufficient in either case to produce a distinct yellow tint. The standard solution is then dropped carefully in from a graduated pipette or burette, and directly the first faint tinge of red is discern- ible and remains permanent on stirring, the whole of the chlorine is precipitated, and chromate of silver, which is a dark red, is formed. The number of c. c. of the solu- tion used before this red tinge is obtained represents the number of grains of chlorine per gallon of water. If, for example, 3*5 c. c. of the solution have been required, the water contains 3*5 grains of chlorine per gallon. The following are examples of the amount of chlorine in different waters : GTS. per Gallon. Thames at Kew -847 Thames at London Bridge . . . 4 '452 Bala Lake - 706 Polluted well at Rugby . . . 7 '5 The indications afforded by the chlorine test have previously been dwelt upon in the remarks on the quali- tative examination of water, and they need not therefore be further referred to here. (4.) Ammonia and Organic Matter. Of the two rival methods of estimating the organic matter in water namely, that of Frankland and Armstrong, and that de- vised by Wanklyn, Chapman, and Smith there is a general concurrence of opinion that the latter is especially suited for the medical officer of health, because it is easy of application, and, so far as chemical analysis can at present indicate, yields sufficiently accurate results for ordinary hygienic purposes. Frankland's process of esti- mating the organic carbon and nitrogen is a method of no small difficulty, and in the hands of any but an ex- perienced chemist the risk of experimental error is very considerable. What is known as the Auiinoni". j/rocess, 186 WATER ANALYSIS. therefore, will be the process described here. For a full description of this process the reader is referred to Mr. Wanklyn's excellent text -book on water analysis, from which the following remarks are for the most part collated. The rationale of the process depends upon the fact that vague and indefinite nitrogenous bodies can be converted into a definite compound, namely, ammonia, and that in this way they can be estimated and expressed as ammonia. Owing to the excessive minuteness of the quantities of nitrogenous compounds which distinguish between a good and a bad. water, it is convenient to adopt a much finer scale of measurement than is requisite for the saline con- stituents ; and the amount of ammonia is accordingly expressed by milligrammes per litre, or so many parts in a million. The re-agents which are employed are the Nessler test, a standard solution of ammonia, a saturated solution of carbonate of soda, and a solution of potassium permanganate and caustic potash. a. Nessler Test. Dissolve, by heating, 35 grammes of iodide of potassium and 1 3 grammes of corrosive subli- mate in about half a litre of distilled water, and after- wards add gradually a cold saturated solution of corrosive sublimate, and keep stirring until the red colour produced begins to be permanent. Then add 160 grammes of caustic potash dissolved in about 200,c. c. of distilled water, and dilute with sufficient water to bring the whole up to a litre. To render the test sensitive, add about 20 more c. c. of the saturated solution of corrosive sublimate, and allow it to stand in a stoppered bottle until the pre- cipitate has subsided. The clear liquid may now be decanted and kept in a tightly stoppered stock bottle ready for use. 1. Standard Solution of Ammonia. Dissolve 3*15 grammes of crystallised sal ammoniac or ammonium chloride in one litre of distilled water. Every cubic WATER ANALYSIS. 18*7 centimetre of this solution contains one milligramme of ammonia. This is termed the strong solution, and is the most convenient to keep. To prepare the dilute solution, put 5 c. c. of the strong solution into a half -litre flask, and fill up with distilled water. This is the standard solution of ammonia, and contains 0*01 milligramme of ammonia in one cubic centimetre of water. c. The Saturated Solution of Carbonate of Soda may be prepared by boiling an excess of the common carbonate in distilled water. About 1 c. c. of this solution is the proper quantity to use, or instead of the solution about one gramme of the dry carbonate of soda, which has just been ignited, may be employed. The carbonate of soda is used in order that the free ammonia may be more easily dispelled on distillation. d. The Permanganate of Potash and Oaustic Potash Solution is prepared as follows : Dissolve 8 grammes of crystallised permanganate of potash, and 200 grammes of solid caustic potash in one litre of distilled water. Boil the solution for some time to free it from all traces of ammonia, and afterwards replace the water lost by eva- poration by adding sufficient distilled water to make up the litre. The distilled water which is used to make up the various solutions may be obtained of sufficient purity from any common drinking water, if care is taken to re- ject the first portions of distillate, and the distillation is not pushed too far. It should always be carefully tested before being used, and so chemically pure that in 100 c. c. there ought not to be 0*005 milligramme of ammonia. The following is a list of the apparatus required for the process (see also Appendix) : A stoppered retort, capable of holding at least one litre; a Liebig's condenser; a good-sized Bunsen's lamp or burner ; a retort-holder ; about half a dozen Nessler glasses made of white glass, 188 WATER ANALYSIS. and with a mark at 5 c. c. ; a half-litre flask ; a gradu- ated burette marked into c. c., to measure off the standard solution of ammonia ; and a pipette marked to hold 2 c. c. It need hardly be said that the greatest care must be taken to have the whole of the apparatus thoroughly clean before it is used. Glass vessels should first be washed out with a little strong hydrochloric or sulphuric acid, and afterwards with pure water. The analysis itself is thus performed : After mount- ing the retort on the holder, and properly connecting it with the Liebig's condenser, half a litre of the water to be examined is poured into it, and 10 c. c. of the solution of carbonate of soda added. The Bunsen lamp is now lighted, the retort thrust well down into the flame, and 50 c. c. are distilled over into a Nessler glass, and Ness- lerised. Then distil over 150 c. c. and throw this distil- late away. This amount is thrown away because it has been found that the first distillate contains exactly three- fourths of the free ammonia present in the water, and it is therefore a waste of labour to Nesslerise the whole of the four 50 c. c. distilled over. There are now 300 c. c. left in the retort, and in order to liberate the "albu- minoid ammonia," 5 c. c. of the permanganate of potash and caustic potash solution are poured into the retort by means of a wide funnel. To prevent bumping, which is very liable to occur with a bad water, the retort should be gently shaken, so as to give the mixture a wavy motion. The distillation is then continued, and three separate dis- tillates, each of 50 c. c., taken and Nesslerised. What is called Nesslerising is the process of ascer- taining the strength of a dilute solution of ammonia by means of the Nessler re -agent, and is indeed one of the most beautiful examples of colorimetric analysis. Let the first distillate of 50 c. c. be taken as an illustration. To this distillate, which is contained in one of the WATER ANALYSIS. 189 Nessler glasses, 2 c. c. of the Nessler re-agent are added by means of the 2 c. c. pipette, which also serves as a convenient stirrer. If, after stirring and waiting about a couple of minutes, the liquid assumes a rich deep brown, it contains much ammonia ; if even a distinct brown tint is developed, it contains a considerable quantity of am- monia ; but if it remain colourless, it does not contain so much as *005 milligramme. When only a light-yellowish tint is produced, the amount of ammonia present is com- paratively small. In any case, however, the exact amount is determined by comparing with a known solution of ammonia. The depth of tint in the distillate is imitated by mixing, in a Nessler glass, more or less of the dilute standard of ammonia contained in the burette with dis- tilled water, and filling up to 50 c. c., and then adding 2 c. c. of the Nessler re-agent. If, after stirring and waiting two or three minutes, the tint developed in the artificially prepared solution is too dark or too light, it is necessary to make another artificial solution of less or greater strength, as the case may be. With a little practice it is easy to approximate very closely to the exact amount of the standard solution of ammonia which will be re- quired to produce a tint on the addition of 2 c. c. of the Nessler re-agent, which will harmonise completely with the tint of the distillate. In order to be able to compare the tints accurately, the Nessler glasses should be placed on a white porcelain slab or sheet of white paper. The number of cubic centimetres of the standard solution of ammonia, which on the addition of the Nessler re-agent were required to reproduce the exact tint given by the distillate, are noted, and the amount of " free ammonia " contained in the sample of water can then be readily calculated. The other three distillates which contain the albumi- noid ammonia are Nesslerised in the same way, and the 190 WATER ANALYSIS. amount of the standard solution of ammonia, which was required to imitate the tint in each case, is also noted. These several amounts added together represent the total " albuminoid ammonia " contained in half a litre of the water. It has already been pointed out that the first 50 c. c. which were distilled over contain three-fourths of the whole of the " free ammonia," and that therefore the next 150 c. c. distilled over may be thrown away. It was formerly the practice of Mr. "Wanklyn to Nesslerise the whole four 50 c. c. to obtain the total of the free ammonia, but the amount contained in the first distillate was found to bear such a constant ratio to the amount contained in the other three distillates, namely, as 3 to 1, that it becomes a needless expenditure of labour to Ness- lerise them. The rule, therefore, is to add one-third to the amount of ammonia found in the first distillate, in order to obtain the whole of the free ammonia. Eemembering now that each cubic centimetre of the standard solution contains '01 milligramme of ammonia, the calculation in any given case becomes very simple. For example, suppose the amount of dilute standard solu- tion of ammonia required to match the tint in each case to be as follows : Free ammonia distillate . . . . . 2 c. c. ( 1st distillate ... 5 Albuminoid ammonia-! 2d . . 2*5 ,, Ud . . -5 then we arrive at the following amounts : Milligrammes. Free ammonia = '02 + -^ = '027 o C 1st distillate ... '05 Albuminoid ammonia -I 2d ,, ... '025 (,3d ,, ... -005 Total albuminoid ammonia . . '08 But, inasmuch as half a litre of water was taken for WATER ANALYSIS. 191 analysis, these results must be multiplied by 2 in order to arrive at the amounts per litre, or per million parts. In the above example, therefore, the results would be stated as follows : Free ammonia Albuminoid ammonia Parts in a million, or milligrammes per litre. 054 16 In this process of water analysis it will be observed from the above description that ammonia is to be looked for at two stages : firstly, in distilling oft" with the carbonate of soda solution ; and secondly, on distilling off with the alkaline permanganate solution. The first portion of the ammonia is called the " free ammonia," because it is ob- tained from the decomposition of those organic impurities in water which are of simple constitution, such as" the ureal class, as well as the ammonia which may be present as ammonia. The second portions of ammonia are named " albuminoid ammonia," because the ammonia which is given off is derived from the oxidation of those more com- plex nitrogenous impurities which are closely allied to albumen. The following are examples of pure, indifferent, and bad samples of water, as determined by the ammonia process : Free Albuminoid Ammonia, parts per 1,000,000. Ammonia, parts per 1,000,000. Quality. Name of Authority. Loch Katrine 004 08 Good Wanklyn Water from Kent Com- pany's mains Edinburgh Water Sup- 01 02 M ply, Colinton, 1867 . 14 08 Indifferent Great St. Helen's pump, London 375 18 Bad > With regard to the inferences which may be deduced 192 WATER ANALYSIS. concerning the quality of a water as indicated by this method of examination, Mr. Wanklyn has laid down the following rules in the third edition of his work on water analysis: "If a water yield '00 parts of albuminoid ammonia per million, it may be passed as organically pure, despite of much free ammonia and chlorides ; and if, indeed, the albuminoid ammonia amount to '02, or to less than '05 parts per million, the water belongs to the class of very pure water. When the albuminoid ammonia amounts to '05, then the proportion of free ammonia becomes an element in the calculation ; and I should be inclined to regard with some suspicion a water yielding a considerable quantity of free ammonia, along with '05 parts of albuminoid ammonia per million. Free ammonia, however, being absent or very small, a water should not be condemned unless the albuminoid ammonia reaches something like "10 per million. Albuminoid ammonia above *10 per million begins to be a very suspicious sign ; and over '15 ought to condemn a water absolutely." But the recent experiments of Dr. Cory, to which reference is made at the close of this chapter, prove clearly that polluting matter, potent for harm, may be present in water which, according to Wanklyn's analysis, may be passed as organically pure, and hence it is of the utmost importance that the surroundings and possible sources of pollution of a particular supply should always be carefully taken into consideration. No matter what pro- cess may be adopted, whether Wanklyn's, Frankland's, Dupre's, or Tidy's, water analysis can only indicate de- grees of impurity and danger, not standards of purity and safety. On the other hand, it must be admitted that there are many surface well-waters in country districts containing even more than "15 parts per million of albuminoid am- monia, and to which no bad effects can be traced, but in WATER ANALYSIS. 193 these cases it is probable that the ammonia is chiefly derived from vegetable matter. If the quantity of chlorine found in a water is exceedingly small, any excess of albu- minoid ammonia would indicate that the nitrogenous matter present is of vegetable and not of animal origin, and therefore comparatively innocuous. At the same time it should be remembered that there might be the same absence of chlorine if the water becomes polluted from the presence of the body of a dead animal in a well or cistern. In conducting a water analysis, it is expedient, if the amount of solids is to be taken, to commence the evapora- tion for the solids first, 'then to commence distilling for the ammonia, and while the evaporation and distillation are going on, to determine the amount of chlorides, and the degree of hardness, if that be considered necessary. It is always advisable to keep a detailed record of the results of every analysis in a book set apart for that purpose. The form of report or certificate will of course vary according to the number of data and the mode of analysis, but the following hints will indicate generally how it should be drawn up : Date of reception of sample, size and description of bottle or bottles, how stoppered or sealed, and how labelled. Physical Examination. Appearance . (Clear, or slightly turbid, etc.) Taste . . (Tasteless, or unpleasant, etc.) Odour . . (Odourless, foetid, etc.) Deposit . . (Slight or large, dirty-looking, flocculent, etc.) Microscopic Examination. (Sandy particles, vegetable matters, animal matters, vibriones, etc.) 194 WATER ANALYSIS. Chemical Examination. Qualitative results : Free Ammonia . (None traces large amount.) Nitrites . . (None traces large amount.) Nitrates . . (None slight traces, etc.) Sulphates . . (None slight traces, etc.) Metals . . (None traces of lead, etc.) Quantitative results : Total solids . (In grs. per gallon.) Chlorides . . (In grs. per gallon.) Hardness, total . (In degrees.) permanent (In degrees.) Free ammonia . (Parts per million.) Albuminoid ammonia (Parts per million.) Remarks as to whether the water is soft or hard, of good quality and fit for use, or whether it is polluted and unfit for use. Date of analysis, signature, etc. As it is becoming customary to express the results of the ammonia process in grains per gallon instead of parts per million, the following formula will indicate the method of calculation : 100 : 7 : : '15 (parts per million) : '0105 (grains per gallon). Exclusive of the microscopic examination, which is seldom undertaken or required, a water analysis giving the above data may be completed in about an hour, provided, of course, that the operator is fairly expert at his work and has all his test and standard solutions pre- pared beforehand. The busy medical officer of health may obtain most of these solutions, as well as distilled water, from chemists, but he should always make blank experiments to test their purity and quality. Although I have thus far endeavoured to describe clearly and concisely the various steps of an ordinary water analysis, I nevertheless consider it very essential that every one who has to undertake this kind of work should receive some lessons in the laboratory of a com- WATER ANALYSIS. 195 petent analyst. If he is precluded from doing this, he may teach himself, provided that he has a fair knowledge of elementary and practical chemistry, but in this case he ought to experiment with samples obtained from a public supply, and compare his results with those of recorded analyses of that supply. As already stated, any proposed new public supply should be submitted to a full quantitative analysis of its saline and other constituents, and for this purpose samples should be sent to a professed analyst. It should not only be usable, but the best which can be procured within the limits of reasonable expenditure. All waters subjected to filtration should be examined from time to time, to ascertain that the filtering process is carried on efficiently. Any water which gives indications of having become con- taminated with animal or other impurities, and which has hitherto been good and wholesome, should be entirely disused until the source of contamination has been dis- covered and removed. A list of tests, etc., is given in the Appendix. Concluding Remarks. Although it must be admitted that the methods of water analyses which are now in use are capable of detecting very minute quantities of organic matter in large volumes of water, it must always be borne in mind, as previously pointed out, that chemical analysis however complete is powerless to indicate any standard of safety when a water becomes specifically polluted. The careful experiments conducted by Drs. Cory and Dupre, at the instigation of the Local Govern- ment Board, and published in the last report of the Medical Officer of the Board, prove clearly that chemistry cannot tell whether a healthy or a diseased body has been the source of any excremental pollution of any particular water. Many of Dr. Cory's observations had special reference to experimental contamination of differ- 196 WATER ANALYSIS. ent waters, some with healthy stools and some with the stools of enteric fever patients, and the results not only gave no indication as to whether the polluting matter came from a healthy or diseased body, but failed to in- dicate the presence of an amount of specifically pollut- ing matter which must have been far in excess of that which proved so disastrous in the well-known Caterham epidemic (see following chapter). The lessons which may be learned from this inquiry are so ably summed up by Dr. Buchanan that I cannot do better than quote them here : " While we must ever be on the watch for the indications that chemistry affords of contaminating matters gaining access to our waters, we must (at any rate until other methods of recognition are discovered) go beyond the laboratory for evidence of any drink- ing water being free from dangerous organic pollution. Unless the chemist is well acquainted w ith the origin and liabilities of the water he is examining, he is not justified in speaking of a water as ' safe ' or ' wholesome/ if it contain any trace whatever of organic matter ; hardly, indeed, even if it contain absolutely none of such matter appreciable by his very delicate methods. The chemist, in brief, can tell us of impurity and hazard, but not of purity and safety. For information about these we must go, with the aid of what the chemist has been able to teach us, in search of the conditions sur- rounding water sources and affecting water services." (Annual Report of the, Medical Officer of the Local Govern- ment Board, 1881-1882.) Very important investigations have also recently been carried out in America under the direction of Professor . W. Millet, of the University of Virginia, for the National Board of Health, which are strongly corroborative of Dr. Cory's results and deductions ; and when, in addition to these, we take into consideration the importance and signi- WATER ANALYSIS. 197 ficance of the researches of Dr. Angus Smith in applying 1 1 Koch's^gelatine process to the detection of minute organ- ' isms in samples of water (see Sanitary Record, 1883), there can be no longer question that present methods are in many respects fallacious, and that a complete reform in water testing is absolutely required before samples submitted for analysis can be pronounced safe. 198 IMPURE WATER, CHAPTEE VIII. IMPURE WATER, AND ITS EFFECTS ON PUBLIC HEALTH. ALTHOUGH impure water has long been recognised as one of the most potent causes of disease, it is only of recent years that minute investigation has succeeded in demon- strating the terrible mortality which it inflicts on all classes of the community. It is true that chemical analysis often fails in detecting the special impurities on which the development of certain diseases depends ; it is also true that, even when impurities are detected, it is extremely difficult to estimate their exact etiological value ; nevertheless, the broad fact remains, and it is founded on evidence of the most conclusive kind, that a vast number of cases of disease are attributable to. the use of impure water, and there are good grounds for believing that, as investigations become more frequent and precise, a continually increasing class of such cases will be discovered. It must also be remembered that the effects of impure water, like the effects of impure air, may engender a general impairment of the health, with- out giving rise to well-pronounced disease. Water impurities and their effects may be conveni- ently considered as follows : Firstly, water rendered impure by an excess of mineral substances ; secondly, water rendered impure by the presence of vegetable matter; thirdly, water rendered impure by animal or- ganic matter. AND ITS EFFECTS ON PUBLIC HEALTH. 199 SECTION I. WATER RENDERED IMPURE BY AN EXCESS OF MINERAL SUBSTANCES. As all potable waters contain a certain amount of mineral matters, it is extremely difficult to decide the quantities of these ingredients which may be present, either singly or collectively, without producing bad effects. This much, however, may be said, that waters of a moderate amount of hardness, provided that the hardness depends chiefly on the presence of calcium carbonate, are not found to be detrimental to health. A water of 8 or 1 degrees of temporary hardness, equivalent to about as many grains per gallon of total mineral solids, may be pronounced good and wholesome, while one of as many degrees of permanent hardness would prove injurious to many persons. With regard to the wholesomeness of Thames water, with a hardness averaging 15 degrees before boiling and 5 degrees after, the evidence given before the Eoyal Commission on Water Supply, 1869, is somewhat conflicting ; for while Dr. Letheby considered a moderately hard water, such as the Thames water, best suited for drinking purposes and the supply of cities, Dr. Parkes maintained that the amount of hardness should not exceed 10 or 1 2 degrees, if possible. Mr. Simon and Dr. Lyon Playfair, on the other hand, although they did not condemn the London water on account of its hard- ness, both expressed themselves in favour of a softer water for purposes of health. The inference that may , be drawn from this and other evidence would therefore jl appear to be this, that the total hardness of a good water ought not to exceed 15 degrees, nor the permanent hard- ness 5 ; or, in other words, that even in a moderately hard wate~r7 calcium carbonate must always greatly exceed the magnesium and calcium sulphates and sodium chloride. 200 IMPURE WATER, The symptoms referable to an excess of hardness, arising from the presence of earthy salts, are mainly of a dyspeptic nature. According to Dr. Sutherland, the use of the hard waters derived from the red sandstone rocks underlying Liverpool, produced in many cases con- stipation and visceral obstruction, and an excess of calcium and magnesium sulphates (7 to 10 grains per gallon) has been known to produce diarrhoea. The special disease, however, which, more than any other, seems intimately connected with the mineral in- gredients of water, is goitre. In some parts of England, such as Yorkshire, Derbyshire, Hampshire, and Sussex, it is found to prevail only in those districts where the magnesian limestone formation abounds. According to Dr. Coindet of Geneva, the disease is speedily produced in persons drinking the hard pump water in the lower streets of that town, while in other parts of Switzerland the use of spring water has been followed by the production or augmentation of the disease in a few days. In India, again, the researches, more especially of Dr. M'Clellan, show very conclusively that it is found to prevail only where the magnesian limestone formation prevails. Whether lime and magnesian salts, or ferrum sulphide, as has been suggested by M. Saint-Lager, be the active agents in producing the disease, has not yet been rendered quite clear; but it appears certain that goitre is originated by water-impurities, and that these are of an inorganic and not organic nature. (Parkes.) The latest authorities on the subject believe the impurity to be of a metallic nature, probably some salt of iron, and explain the prevalence of the disease in localities where the magnesian limestone formation pre- vails, by maintaining that metalliferous earths are always to be found in those districts. In support of this view it must be admitted that in many limestone localities AND ITS EFFECTS ON PUBLIC HEALTH. 201 the disease is by no means prevalent, as for example, in Scotland, Ireland, Norway, and Sweden, where mountain limestone enters largely into the geological formation. (Quain's Dictionary of Medicine.) With regard to this subject, Dr. Brushfield, formerly of Brookwood, Woking, has directed my attention to the prevalence of goitre at Pirbright, a village near Brook- wood, especially amongst the inhabitants who live along the course of a certain brook. Even the clergyman's wife contracted the disease after she had been resident there for a short period. But instead of magnesian lime- stone, the geological formation throughout the district consists of Bagshot sands overlying the London clay. Goitre has become much less common since sanitary matters have been better attended to. The effects of minute traces of metallic compounds in drinking water are as yet comparatively unknown. It is quite possible that the sanitary condition of a district may in some measure depend on impurities of this de- scription, and, as Mr. Wanklyn suggests, that the salutary effect of " change of air " may be partly due to change in the minute metallic impurity in the water of the parts of the country which are visited. Of the metallic ingredients, the effects of iron and lead have been the most fully ascertained. It would appear that iron, if present in quantities large enough to impart a chalybeate taste to the water, often produces headache, slight dyspepsia, and general mal-aise, while impregnation with lead from leaden cisterns or pipes has frequently been followed by symptoms of lead-poisoning. In the case of the ex -royal family of France, many of whom suffered when at Claremont from this species of water contamination, the amount did not exceed one grain per gallon ; indeed, from cases which have since occurred, it seems probable that the habitual use of water containing 202 IMPURE WATER, from* one- ten tli to one- twentieth of a grain per gallon may be attended with danger. In his investigations with regard to the Devonshire colic, which formerly pre- vailed to a great extent, Sir George Baker found that eighteen bottles of cider which he examined contained 4-J- grains of lead, or a quarter of a grain to each bottle. The impregnation arose from lead being employed in the construction of the cider troughs. With regard to the minor effects of lead-poisoning, there are good grounds for believing that many obscure forms of disease, partak- ing more particularly of the nature of dyspepsia and colic, are due to this cause. Arsenic, copper, or mercury, are only found in the drinking waters of this country in injurious quantities when streams are polluted by the washings from mines or chemical works. SECTION II. WATER RENDERED IMPURE BY VEGETABLE MATTER. Vegetable matter may be present in water either in suspension or in solution. In peaty water, which is characterised by its brownish tint, the dissolved impurities sometimes do not exceed two grains per gallon. In the absence of a purer supply, a water of this description cannot be pronounced objectionable, provided that it is not stored in leaden cisterns, and that the supply is con- stant. If stored in open-air ponds or reservoirs it is improved by oxidation and light ; and it is further im- proved by filtration through gravel and sand. Water containing a considerable amount of vegetable matter, partly in suspension and partly in solution, is decidedly unwholesome. It has been known to produce violent outbreaks of diarrhoea, and, since the days of Hippocrates downwards, it has been popularly acknow- AND ITS EFFECTS ON PUBLIC HEALTH. 203 ledged to be productive of ague and other malarious ailments. In this country there are several instances on record, that ague has been much lessened in small communities by using well instead of surface water ; and there is strong presumptive evidence that, apart from the influences attaching to improved drainage, the great decline of this disease throughout many parts of England, where it formerly prevailed, is in some measure due to the use of purer water. (Parties.) SECTION III. WATER RENDERED IMPURE BY ANIMAL ORGANIC MATTER. From a sanitary point of view this is by far the most important class of water impurities. The presence of putrescent animal matter, whether it has percolated through the soil from cesspools or other filth-accumulations into wells, or whether it has been discharged from open sewers into streams and rivers, converts drinking water into a dangerous poison, fraught with disease and death. It is true that to a certain extent the process of filtration through a porous soil tends to render less hurtful the sewage which dribbles into a well, but after a time this purifying power is lost, thejsoil ]becomes_.sodden, and the sewage enters unchanged. It is also true that, given a sullicieiitly large stream, a sufficient length of course, and a sufficient length of time, the greater portion of the sewage discharged into a river will become converted into harmless products by oxidation. Yet neither process can be trusted, however complete it may appear to be. There is always danger lurking in a water which is known to be contaminated with animal matter, and more especially when such matter is partly composed of the evacuations of patients suffering from certain specific diseases, such as cholera or enteric fever. The germs of disease, which 204 IMPURE WATER, may be communicated in this way, have a tenacity of life or chemico-physical power altogether beyond our knowledge. Leaving out of consideration the question whether animal organic matter in suspension or in solution is the more injurious to health, it would appear that it is the quality rather than the quantity which determines the clanger. As already stated, a trace of faecal matter, espe- cially when undergoing active chemical change, may render a public well poisonous, while a stream of sewer-gas may contaminate the contents of a cistern, and be the means of prostrating a whole household. The principal diseases which have been proved to be produced by this class of water impurities are, cholera, enteric fever, dysentery, and diarrhoea. 1. Cholera. Although much had been previously written with regard to the etiology and spread of cholera, it was not generally surmised that the disease could "be propagated by a polluted water-supply until the late Dr. Snow published the results of his researches in 1849. At first Dr. Snow's views were rejected by some, or ques- tioned by others; but in 1854 there occurred a violent outbreak of cholera in the parish of St. James, West- minster, the causes of which were inquired into by a committee of medical men, whose report fully substantiated Dr. Snow's conclusions. Between the 31st August and the 8th September of that year, as many as 486 fatal cases occurred within an area bounded by a circle whose radius scarcely exceeded 200 yards. On inquiring into the local peculiarities of the epidemic, Dr. Snow found that, the sufferers had been in the habit of drinking the water supplied by a pump-well in Broad Street, which had a great reputation for freshness and sweetness. An analysis of the water proved that it was highly charged with animal impurities, and, at Dr. Snow's earnest solicita- tion, the handle of the pump was removed by order of the AND ITS EFFECTS ON PUBLIC HEALTH. 2Q5 vestry on September 8th, to prevent further use of the water. After this the disease gradually subsided, and ultimately disappeared. It was made manifest, by a // subsequent examination, that the sewage of a neighbour- ing house had leaked into the well, and it was further ascertained that the evacuations of a patient residing in the house, and who was suffering from diarrhoea, or actual cholera, must have mingled with the sewage immediately before the occurrence of the general outbreak. No evi- dence could well be more convincing that, in this instance at least, the choleraic poison had been conveyed by the drinking water. Amongst other remarkable outbreaks, which go to prove that this mode of cholera propagation is not at all uncommon, may be mentioned the following : In the autumn of 1865, a gentleman and his wife, from the village of Theydon-Bois in Essex, had been lodging at Weymouth for two or three weeks, and returned home towards the end of September. On their way home they passed through Dorchester, where the gentleman was seized with diarrhoea, vomiting, and cramps, which con- tinued more or less during the next day and the day following, when they reached Theydon-Bois. During the journey the wife also began to complain of abdominal pain, which was followed by diarrhoea and eventually by cholera, from which she died. A few days after their return the disease rapidly attacked other members of the household, so that, " within a fortnight, in that one little circle, eleven persons had been seized with cholera mother, father, grandmother, two daughters, son, doctor, serving-lad, servant-maid, labourer, and country-woman ;. arid of these eleven only three survived the son, a daughter, and the serving -lad. Later, in the country- woman's family, there was another fatal case. It cannot well be doubted," continues Mr. Simon, "but that the 206 IMPUKE WATER, exciting cause of this succession of events was, in some way or other, the return of the parents from Weymouth ; of the father with the remains of choleraic diarrhoea still on him, of the mother with apparently the beginnings of the same complaint. But this is only part of the case, and the remainder teaches an impressive lesson. All drinking water of the house came from a well beneath the floor of the. scullery, and into that well there was habitual soakage from the water-closet." (Eighth Eeport of the Medical Officer of the Privy Council.) In addition to Mr. Simon's report on the cholera epidemics of London in 1848-49 and 1853-54, in which there is sufficient evidence to show that the pre valency of the disease in certain districts was almost entirely deter- mined by the degree of impurity of the water-supply, the conclusions, more especially of Dr. Parr and Mr. Eadcliffe, with regard to the localisation and distribution of the epidemic of 1866, are, if possible, more confirmatory still. Thus, Dr. Farr, in his evidence before the Eoyal Commis- sion on Water Supply in 1869, stated -that "in all the districts supplied by the Grand Junction, the West Middlesex, and the Chelsea Waterworks Companies, the mortality was about 3 in 10,000 ; in those supplied by the Southwark and Lambeth Companies, which were for- merly so heavily visited, it was about 6 in 10,000 ; and in those supplied by the New Kiver Company, about 8 in 10,000 ; while in those supplied by the East London Company, from the Old Ford Eeservoirs, it was 79 in 10,000." In effect, the area of explosion was found to be limited to the district supplied by the East London Water Company, and not only so, but Mr. Kadcliffe's investigations proved that the water delivered from the Old Ford covered reservoirs had been polluted with water from the filthy uncovered reservoirs, and that these latter had, in all probability, been contaminated with soakage AND ITS EFFECTS ON PUBLIC HEALTH. 207 from the Eiver Lea, which received the evacuations of the first two patients who died of epidemic cholera in the eastern districts. With regard to Scotland, the evidence of Dr. Steven- son Macadam, as to the influence of impure water on the spread of cholera, is also very conclusive. In a report read before the members of the British Association in 1867, he showed very clearly that the ravages of the disease were coincident in time and place with the use of water from impure wells, and that in all cases the abate- ment of the outbreak followed the introduction of a pure and fresh supply. Without quoting further evidence, it is sufficient to state that the weighty authority of Dr. Parkes strongly confirms this view of choleraic contagion ; and indeed the opinions of Professor von Pettenkofer, though at first sight they appear to be antagonistic to the theory, do in reality support it. For, while he considers that the pro- pagation of cholera is due to a fermentation of the rice- water stools, he also maintains that this ferment can only act, and the contagion be generated, under certain local conditions namely, when there is a damp porous subsoil to receive the ejecta. Although Pettenkofer believes that the air is the sole channel by which the .cholera miasm, thus generated in the soil, is spread, there is no doubt that the bearing of the geological influence amounts only to this, that where populations are living on a damp open subsoil, with no artificial water-supply, nor any effi- cient system of drainage, there the drinking water, as well as the local atmosphere, is almost certain to be largely polluted by those frecal impurities amid which the diar- rhceal contagia are peculiarly apt to multiply. (Simon.) Whether cholera can be produced by animal organic matters not of a specific nature, is still an open question. Very probably the effect of constantly drinking a certain 208 IMPURE WATER, amount of these impurities produces a lowered state of the system and a tendency to diarrhoea, so that, when the cholera poison is abroad in the atmosphere, it finds its victims in largest numbers amongst those who partake of an impure water-supply. This much, however, appears certain, that whenever cholera evacuations make their way into the drinking water, we may expect to find the disease burst forth with the greatest virulence and fatality amongst those who use the water, and that indeed the endemic area will approximate with remarkable closeness to the limits of the district which it supplies. 2. Enteric or Typhoid Fever. The remarks which have just been made with regard to the influence which impure water exerts on the spread of cholera, apply with still greater force to the etiology of enteric fever. For, although there are still some who do not believe in the com- municability of the disease, there is a constantly accumu- lating amount of evidence, which goes to prove not only that the poison of the fever may be conveyed through the agency of water from the sick to the healthy, but that this is the most common mode of propagation. Sir W. Jenner, than whom no higher authority could well be quoted, in commenting on this point, says, " The spread of typhoid fever is, if possible, less disputable than the spread of cholera by the same means. Solitary cases, outbreaks confined to single houses, to small villages, and to parts of large towns cases isolated, it seems, from all sources of fallacy and epidemics affecting the inhabitants of large though limited localities, have all united to support by their testimony the truth of the opinion that the ad- mixture of a trace of feecal matter, but especially the bowel excreta of typhoid fever, with the water supplied for drink- ing purposes, is the most efficient cause of the spread of the disease, and that the diffusion of the disease in any given locality is limited, or otherwise, and just in proper- AXD ITS EFFECTS OX PUBLIC HEALTH. 209 tion as the dwellers of that locality derive their supply of drinking water from polluted sources." According to the late Dr. William Budd it also appears to be highly probable that when the poison is conveyed by water, infection is much more certain than when it is disseminated by the air ; and in support of this statement he instances an outbreak which occurred in Cowbridge in Wales, in 1853, where, out of some 90 or 100 persons who went to a ball, fully one - third were shortly after- wards laid up with fever. Although the water was not examined, there was satisfactory reason to believe that it was polluted. Since that date numerous other local outbreaks have been carefully investigated, and some with so much pre- cision and completeness of detail that they are noticed here rather as examples of the painstaking and systematic way in which such inquiries should be conducted than as proving this mode of propagation of enteric fever : (1.) In the spring of 1867 Dr. Thome, one of the Health Inspectors of the Privy Council, was ordered to proceed to Winterton in Lincolnshire, to inquire into the causes of the excessive mortality from enteric fever which had prevailed more or less during the previous two years in different parts of the town, but had latterly assumed alarming proportions. The small town numbered about 1800 inhabitants, of whom about nine-tenths consisted of the labouring classes, living for the most part in well- built cottages and earning good wages. Absolute poverty was little known amongst them, intemperance was rare, and only in two instances was there any overcrowding. Moreover, the situation of the town was healthy, inasmuch u-j it was built on a gentle slope facilitating drainage, and the subsoil was open and porous, consisting of a stratum of oolitic limestone covered by a light marly soil. Yet, with all these advantages, the number of deaths in 1865 210 IMPURE WATER, amounted to 51, and in 1866 to 44, and of these more than a third had died of enteric fever. At the date of Dr. Thome's visit 55 cases were under treatment, and already 6 deaths had occurred since the beginning of the year. The cause of all this sickness and mortality is best given in Dr. Thome's own words : " The epidemic prevalence of fever in Winterton is undoubtedly to be ascribed to the disgraceful state of the privies, cesspools, ashpits, c^nd wells. With the exception of about six houses, where water-closets have been con- structed, all the cottages are provided with privies, which are generally built of brick, and have an aperture at the side or back, through which they can be cleaned out. This aperture I found open in almost all instances, and the result of this is that the contents of at least half the privies in the town run out into the gardens, soak into the earth, and penetrate in many instances into the wells, besides producing the most offensive odour. In addition to this many of the tenants either throw their refuse and slops, including urine, into the yards outside their doors, or else they improvise a receptacle by digging in the ground close to the aperture in the privy wall. The ftecal matter pours into it, and they thus add to their pre- vious list of nuisances that of an open cesspool. In some instances ashpits have been built, but these are uncovered, and since urine and the bowel discharges of the typhoid patients are thrown into them, in addition to other refuse, they are but little better than open privies. All these sources of ecal fermentation are situated, as a rule, close to the houses, and in some instances within a few feet of the back doors, and just under the windows. The wells are also in their immediate neighbourhood, and many of the inhabitants informed me that their water was so bad that they had been compelled to discontinue drinking it. In one instance I found the space between two pigstyes AND ITS EFFECTS ON PUBLIC HEALTH. 211 entirely occupied by a well 3 feet in diameter. Fever is present in the house to which this well is attached, but since the occupants do not use it, the necessarily conta- minated condition of the water cannot be considered to bear upon the disease. Given the existence of typhoid fever in a town, it is hardly possible to conceive of con- ditions more favourable for its spread than those existing in Winterton." (Tenth Eeport of the Medical Officer of the Privy Council.) (2.) In the autumn of the same year (1867) a severe epidemic of enteric fever broke out in Guildford. Dr. Buchanan, who was the Government Inspector on this occasion, found that during the first twenty-eight days of August, 10 cases of the disease had occurred in different parts of the town ; when suddenly, within the next thirty- three days, the number rose to about 250. As the epidemic was almost exclusively confined to a part of the town which corresponded with a particular section of the public water-supply, suspicions were aroused that this had become polluted ; and on further investigation it was as- certained that on a particular day, about ten days before the outbreak, the houses in that part of the town had been exceptionally supplied with water from a certain high- standing reservoir which had previously been filled from a new well. This well was sunk through a porous stratum of chalk, and in close proximity to it were various sewers, one of which was afterwards found to be leaking in several places. There was no doubt, therefore, that sewage had oozed through the chalk into the well, and had caused the epidemic. An analysis of a sample of the water was subsequently made by the late Professor Miller, the results of which gave unmistakable evidence of previous sewage contamination. (Tenth Eeport of the Medical Officer of the Privy Council.) (3.) The account of the epidemic at Terling, in Essex, 212 IMPURE WATER, by Dr. Thorne, is especially valuable as showing the effect of a sudden rise of the ground water level in a village situated on a porous subsoil, obtaining its water-supply from shallow wells, and allowing its excrementitious filth to accumulate in badly-constructed privies and manure heaps, or to lie indiscriminately in scattered masses on the surface of the ground. Out of a population of 900, about one-third of the number were attacked with enteric fever within a period of two months, and 41 had died. Some ten days before the outbreak, and after a period of prolonged drought, a sudden great rise in the water-level of the wells was observed to follow a heavy fall of rain and snow ; in other words, the shallow unprotected wells sunk in the porous gravel had become converted into so many receptacles for the washings of the filth-sodden soil, and hence the epidemic. (Tenth Report of the Medical Officer of the Privy Council.) (4.) In the beginning of 1873 a severe outbreak of enteric fever occurred in the small town of Sherborne in Dorset, which was investigated by Dr. Blaxall, and which is of extreme interest as having been the first outbreak of the kind which was clearly traced to the entrance of sewer air into the water-mains. Although the water- supply was intended to be constant, it was ascertained that in December 1872, and January 1873, the water was frequently shut off at a point near the reservoir, and that during the month of February it was shut off every night. It was observed that when the water was turned off there were certain water-mains up which there was a sudden rush of air immediately the tap was unscrewed, and as many of the mains communicated directly with closet-pans by means of taps, which were sometimes left open, and which in other instances were broken, there were thus numerous inlets for the entrance of air from the closet-pans into the water-mains. Moreover, if a pan AND ITS EFFECTS ON PUBLIC HEALTH. 213 happened to become full of excremental filth, there was the probability of excrement as well as sewer air having been sucked into the mains. In January and February there were about 27 cases of fever in the town, but before the end of April the number altogether had increased to 240, out of a population of 6041. After the first week, during which 73 cases occurred, the water-supply was again ma le constant, and the epidemic gradually declined. (Mr. Simon's Reports, New Series, No. II.) In April 1882, Dr. Blaxall was commissioned to pay a second visit to Sherborne, to investigate a limited out- break of enteric fever which was confined to three house- holds, and it is very noteworthy that the fresh outbreak afforded a second illustration of similar evils appearing to result from the self-same cause. For although general disconnection of the closets from water-mains and better ventilation of the sewers had been carried out in con- sequence of Dr. Blaxall's first report, it was very signi- ficant that such disconnection had not been effected in respect to the closets of the houses to which the second outbreak was limited ; indeed, the result of the inquiry, as in the first outbreak, confirmed the opinion that the drinking of water contaminated by sewer air was the channel by which the disease was spread. Owing to the improvements which had been carried out there had been no deaths from enteric fever from 1873 to 1882, except during one year. (Special Eeport to Local Government Board.) (5.) Somewhat akin to this outbreak in its mode of \ / causation was the outbreak of enteric fever which occurred at Caius College, Cambridge, towards the close of 1873. Dr. Buchanan's report on this outbreak is such a model of painstaking research and sound reasoning, that, apart altogether from its intrinsic value as a contribution to the etiology of fever, it ought to be read by every medical 214 IMPURE WATER, inquirer as one of the most lucid expositions in the domains of medical logic. Without detailing at any length the various interesting phases of the inquiry, it will be sufficient here to state that the cases of fever numbered 15, that the incidence of these cases was wholly upon the 112 students who were resident in the college, and that 12 out of the 15 cases were confined to 63 students, residing in a particular part of the college, namely Tree Court. The buildings connected with this particular court had been erected only four years pre- viously, and such an amount of care had been expended on the sanitary arrangements that any injury to health arising from drains, sewers, or water-pipes, seemed well- nigh impossible. Nevertheless, the chances as a matter of a priori probability were as 24 to 1 that the cause of fever depended upon some condition peculiar to Tree Court, and not operative, or only operative to a very limited extent, in other parts of the college. After con- sidering all the more usual ways in which enteric fever is known to be spread, and finding that none of them could account for the intensity of the incidence of the outbreak in Tree Court, Dr. Buchanan's suspicions were directed to the water-supply. Now, the water-supply of the college was taken from a surrounding 5 -inch main at six different places, and at one of them, namely at the Gate of Humility, there was a branch main which supplied Tree Court and no other part of the college. In short, the area of this particular water distribution was the area of the fever, and although there was no doubt that the quality of the public water-supply was good, this was no argument against a " local contamination in a local ser- vice." It had struck Dr. Buchanan at an early stage of the inquiry that the closets in Tree Court were the only closets in the college which were not provided with cisterns, but were supplied with water direct from the AND ITS EFFECTS ON PUBLIC HEALTH. 215 high-pressure constant main ; and on further inquiry the following facts were ascertained : (1) That, according to the servants, there was occasional intermission in the constant service of water-supply ; (2) that there had been two actual intermissions during the term, one of which occurred about October 25th, or a fortnight before the first case, and the other certainly on November 1st, a fortnight before the date of the second, third, and fourth attacks ; and (3) that although the mains were supplied with valve-taps which were believed to prevent any re- gurgitation of air or water, it was clearly proved by experiment that there was a reflux of air and water into the main when the water was turned off, and that the valve-tap was useless in this particular instance for the purpose for which it was intended. Of the closets in Tree Court, two were found to be connected directly with the water-main which supplied drinking water for the whole of the court, and it is on the structural arrangements of these closets that the chief interest of the inquiry depends. One was situated in the basement of the porter's lodge, the other in the staircase, at an elevation of about 30 feet above the surrounding water-main, and about 5 or 6 feet above the level of the former. Both closets were of similar con- struction, and both were considered to have assisted in contaminating the water-supply, but from its higher ele- vation there was greater probability that the closet in the staircase played a much more direct part than the one on the basement. This closet was ascertained to be of the S-bend pattern, but, in addition to the pipe communicating directly with the pan, there was found to be a smaller branch pipe dipping into the opening of a second S-bend, which was also connected with the soil-pipe, and which wns intended to drain the " safe " of the closet in case of its being flooded. There were thus two channels through 216 IMPURE WATER, which influx of air could take place when the water- supply became intermittent, and in the case of the smaller branch there was the further possibility of liquid filth . being sucked into the water-main under certain conditions. At all events, the air which thus entered " must have been essentially sewer air," and in this case the danger of such air forcing its way through traps was greatly in- creased by the circumstance that the sewer in the neigh- bouring street was unventilated, and that between the sewer and the closet there was no opening or trap of any kind connected with the excrement pipe or drain. It was further discovered that during the month of October this sewer received the discharges of patients suffering from enteric fever in other parts of the town, so that there was the probability of the sewer air having been at the time specifically contaminated. Lastly, and this is a most significant feature of the inquiry, Dr. Buchanan thought it desirable that the smaller branch pipe and part of the other pipe should be submitted to chemical examination, it having been observed that the end of the former was crusted over with a dirty-looking layer, and that the inside of both was lined with deposit. The analysis was accordingly made by Dr. Dupre* of "West- minster Hospital, who certified that the dirty -looking layer consisted of " a very large proportion of nitrogenised organic matter, and a very considerable proportion of phosphoric acid," and that he had little doubt that it was derived from " water strongly impregnated with faecal matter." The deposit inside the pipes was of a similar character, so that, as Dr. Buchanan puts it, " Dr. Dupre's results show, first, that (as circumstantial evidence ap- peared to- indicate) excremental matter actually had entered the water-pipes of the staircase closet, and secondly, that it had in fact (what had before been sug- gested as a possibility) entered the water-pipes as a 'AND ITS EFFECTS ON PUBLIC HEALTH. 217 liquid. In no other way can the presence of phosphates in those pipes be accounted for." (Mr. Simon's Reports, New Series, No. II.) (6.) While there can be little doubt that this parti- cular mode of enteric fever propagation is much more frequent than is usually suspected, the following outbreak will suffice to show the dangers which threaten any town where closets directly connected with water-mains are numerous, and where the water-supply is intermittent : During the latter half of the year 1874 an epidemic, of enteric fever prevailed in the town of Lewes, of such severity that out of a population of about 11,000, nearly 500 cases had occurred, and as many as 104 of these took place during the last week of October. Dr. Thome, who was appointed to report upon this outbreak, dis- covered, after minute inquiry, that "it was due, in the first instance, to pollution of the town water-supply by water drawn from the Ouse, which receives the town sew- age, but mainly spread by suction of polluting matter into the water-pipes of an intermittent water service." So soon as it became clear that the epidemic was not only favoured, but practically insured, by the intermittent water-supply, Dr. Thorn e urged the necessity of a constant service, and when this was obtained the epidemic became virtually arrested. (Mr. Simon's Reports, New Series, No. IV.) Although in these several epidemics there was no direct evidence to show that the outbreak depended, in the first instance, on the presence of the enteric poison in the sewage which contaminated the water, it is nevertheless note- worthy that cases of the fever were more or less common in the several localities previous to the outbreak. The following outbreaks, however, are strongly corroborative of the view which is maintained by many that the disease is essentially a specific disease, and can only be propagated by means of a specific contagium : 218 IMPURE WATER, (a.) In 1872, an outbreak occurred at Niamey, a village near Frome, and Dr. Ballard, the Local Govern- ment Inspector, who was sent to investigate the causes of the outbreak, thus states the conclusions deducible from his inquiry : " 1, That the fever at Nuimey was enteric ; 2, that it was brought into the village from a distant place by an individual whose evacuations, and those also of others attacked in the same and in the adjoining house, found their way into the Nunney brook, at the upper part of the village ; 3, that the fever spread in the village in consequence of the villagers habitually drinking the water of the brook thus contaminated, which water was still further polluted with the sewage of the village itself, containing, if not the actual excrement of .the sick, yet certainly matters washed out of their soiled linen, and also more or less of their liquid evacuations ; 4, that at the time of my visit, actual excrement from cases of enteric fever was finding its way into the brook at a hamlet only half a mile above the village of Nunney." (Med. Times and Gazette, 1873.) (b.) The outbreak at Over Darwen, which occurred towards the close of 1874, is alike remarkable for its terrible severity and for the thoroughness with which the cause of the outbreak was traced to its origin. According to Dr. Stevens, who was appointed by the Local Govern- ment Board to inquire into and report upon the epidemic, the first case occurred at a house some considerable dis- tance from the town, but not very far distant from the public water-main. The patient, having contracted the disease elsewhere, afterwards came home ill, and died there. On first inquiry it was stated that the water- supply could not by any possibility be polluted by the excreta from this case, but subsequent investigations ren- dered it only too apparent that here lay the whole cause of the epidemic. It was discovered that the drain of the AND ITS EFFECTS ON PUBLIC HEALTH. 219 closet into which the excreta of this patient were thrown crossed the line of the water-main, and though special precautions had been taken by way of cementing and the like to prevent any leakage, it was found that the drain had become choked up, that the cement had given way, and that the contents of the drain were sucked freely, indeed regularly, into the water-main. No doubt the general filthy condition of the town greatly aided in pro- pagating the epidemic after the specific contagium had been distributed by means of the water-supply, but the terrible rapidity with which the disease spread pointed clearly to specifically polluted water as being the prime cause of the epidemic. Out of a population of about 22,000, 2035 people were attacked within a very short period, and of these 104 died. (Sanitary Record, 1875.) (c.) In the small village of Lausen, in Switzerland, there occurred an outbreak of enteric fever in 1871 which proved that even filtration through a considerable tract of porous soil will not purify water which has once" been specifically tainted. It was found, when the outbreak was investigated, that all the houses in the village, with the exception of six, were supplied with water by means of wooden pipes, from a certain spring, and that the out- break was confined to the inhabitants who drank this spring-water, the other inhabitants, who drank well-water, having entirely escaped. That the disease had been in- troduced by -the spring- water was made clear by the fol- lowing facts : Behind the village there is a hill about 300 feet high, the westerly spur of which extends into a small side valley, and through this valley runs the Furler brook. Connected with this brook there were the latrines of several scattered farm-houses, in one of which four persons had suffered from enteric fever in the months of June and July. Although at first sight it did not seem possible that there could be any connection between these 220 IMPURE WATER, cases and the outbreak at Lausen, it was ascertained that when the meadows in the Furler valley were watered by damming up the brook, the spring increased in amount, and that when they were thus treated in July, it yielded a turbid and bad -tasting water. Not long afterwards, namely, on August 7, 10 inhabitants were attacked, and in nine days more 5 7 persons were prostrated with the disease, the number reaching to 130 at the end of October. To prove that the Furler brook could contaminate the. spring at Lausen, the experiment was tried of putting common salt into the brook, when it was discovered that the spring water became quite briny. (Deutsch. Arch, fur Klin. MerL, 1873.) (d.) In the early part of the year 1879 there occurred a severe outbreak of enteric fever at Caterham and Kedhill in Surrey, in which, within a period of about six weeks there were about 370 cases and 21 deaths. The outbreak was investigated by Dr. Thome, and his report, apart from its painstaking nature, is of special interest, inasmuch as the disease was brought about under conditions which stand alone in the history of such epidemics. Before Dr. Thome commenced his inquiries, Mr. Jacob, the medical officer of health for the combined Surrey sanitary districts, had come to the con- clusion that, as regards Kedhill at least, which was under his supervision, there could be little doubt that the disease, judging from its incidence, was associated with the public water-supply. That supply, like the supply for Caterham, was derived for the most part from deep wells belonging to the Caterham Waterworks Company, and after inquiring into other probable sources of the disease, such as the drainage and milk-supply, the evi- dence became quite conclusive that it had been caused by the use of this water. But this view received no support, either from consideration of the source of the AND ITS EFFECTS ON PUBLIC HEALTH. 221 supply or from its course or mode of distribution. It was derived from wells over 500 feet in depth, there was no evidence that there had been leakage into them from any neighbouring cesspits, the supply was constant, and no accidental contaminations could be ascertained con- nected with the mains. But while the probable causation of the epidemic was thus being gradually narrowed, certain circumstances came under Dr. Thome's notice which led to inquiries in quite an unexpected direction. It appears that during the latter part of 1878 and the beginning of 1879 the Caterham Waterworks Company constructed an adit from one of their old wells leading to a new bore which was then being sunk. A number of men were employed in the construction of this adit, and inquiry was made as to whether any of them had ailed while the work was going on, when it was ascertained that one of them had left the work some time in January, and was believed to have been ill. This man was sought out by Dr. Thorne and Mr. Jacob, and, on being questioned, stated that he worked in the adit, that up to January 5th he was quite well, but about that date began to suffer from diarrhoea, aching pains all over, loss of appetite, shiverings followed by feelings of feverish heat, and gradual prostra- tion. Nevertheless, he continued at his work up till January 20, the diarrhoea all the while being of a most persistent character, and so liquid at times that it occa- sionally " ran from him." While the work was going on it was expected that all the men who were employed in the adit should make such preparation before descending the well that no occasion should exist for relieving them- selves below, but should any such occasions arise, the buckets employed in excavating were to be used. Now, this man admitted that he was compelled to evacuate in the adit at least two or three times each shift, and though he denied that he ever did so without using a bucket, 222 IMPURE WATER, " there were undoubted means by which his evacuations could have found their way into the water." Although he was not attended by any medical man, there could be little doubt, therefore, that all this while he was suffering from, a mild form of enteric fever, and it was further ascertained that on December 25 and 26 he paid a visit to some friends in Croydon, where he had undoubted opportunity of contracting the disease. All these circum- stances are then summed up as follows : " Here then were the stools of an enteric-fever patient, from about January 5 onwards, getting into the Cater- ham Company's water, and distributed with that water to the district served by the company. "Now we know from ample experience that enteric fever is produced, and produced with the maximum of certainty, when the specific evacuations of that disease are consumed by a population. Again, it is a matter of experience that where enteric fever has been conveyed through water, some fortnight has to elapse between the distribution of the water and the occurrence of the disease among the community served by it. But a fortnight after January 5 is the very day when the first case of fever occurred, and during the fortnight following upon the period January 5 to 20, i.e. from January 19 to February 3, the disease became widely spread through- out Caterham and Eedhill ; the distribution of the .fever being limited, as we have already seen, to houses supplied with the water of the Caterham Company. There can, I think, be no doubt but that we have in the man J. K. the cause of the disease which followed." There are other points of great interest in this mas- terly report, some of them explaining what at first sight might be called the capricious spread of the disease, but all of them go to prove that the evacuations of this work- man were the sole cause of the epidemic, while the re- AND ITS EFFECTS ON PUBLIC HEALTH. 223 medial measures which Dr. Thome recommended were speedily followed by a complete cessation of the outbreak. (e.) During the summer and autumn of 1882, a very extensive outbreak of enteric fever prevailed in Bangor and the immediate neighbourhood, which forms the sub- ject of a special report by Dr. Barry, one of the Local Government Board Inspectors. The initial cause of the outbreak, as previously traced by Mr. Eees, the Medical Officer of Health for the Carnarvon combined districts, was found to be due to specific pollution of the public water-supply, which is obtained from a small stream called the Afon Gaseg. It appeared that towards the end of May a case of illness which was subsequently confirmed to be enteric fever, occurred in a detached house at Llwynrhandir, and the drain from this house discharged into a small rapid stream, which in its turn discharged into the Gaseg at a point about 350 yards above the intake of the Bangor water-supply, the whole distance from the house to the intake being about 700 yards. The incidence and simultaneous appearance of the disease in various districts and streets at once suggested some common medium of infection, and all the facts pointed clearly to a tainted water-supply. The main points con- nected with the outbreak are summarised by Dr. Barry as follows : " (1.) That the original case at Llwynrhandir, which began on the 22d May, had probably been passing in- fected matter into the Gaseg, to a greater or less extent, from that date until June 30th. " (2.) That prior to June 26th, two further cases had occurred in the same house, and that in these, owing to the mildness of the disease, no precautions had been taken, and the danger of infected matter passing into the stream had been thereby much increased. " (3.) That owing to the flushing and consequent 224 IMPURE WATER, bursting of the water main, considerable disturbance occurred in the water-supply on June 30th and July 1st. " (4.) Finally, that a simultaneous outbreak in various new localities occurred from ten days to a fortnight after this took place." The first period of the outbreak, which extended from the last week in May to the end of the first week in July, was characterised by a continued series of dropping cases occurring simultaneously in different parts of the town and district. During this period there was every reason to believe that a considerable amount of the infected material was retained in the very imperfect filtering beds, and when these were disturbed after the bursting of the water-main, the water became impregnated to a much more dangerous extent, and hence the sudden outbreak which characterised the second period. After a time the sewers became seriously infected, and no doubt the disease was subsequently spread in this way, though the tardy action of the sanitary authority in cutting off the source of pollution, and removing the filtering material, contri- buted to swell the alarming dimensions of the outbreak. Altogether the number of cases amounted to 540, out of a population of about 10,000 in the town and infected neighbourhood, and of these 42 had proved fatal up to September 12th. In stamping out the t outbreak, it may be added that tents were largely used for isolating the patients. (Special Report to Local Government Board?) The following outbreak merits particular notice, on account of its unique character, and as being the first of the kind reported. During the course of the first week in August 1882, Mr. George Fosbroke, medical officer of health for the combined Stratford-on-Avon districts, was called upon to investigate an outbreak of enteric fever which had suddenly assumed unusually extended propor- tions in the town of Evesham and the adjoining neigh- AND ITS EFFECTS OX PUBLIC HEALTH. 225 bourhood. Before the close of September as many as forty- eight cases had occurred in the borough, and twenty- one in the rural districts, five of the former and three of the latter having proved fatal. The suddenness of the outbreak, widely scattered though many of the cases were, pointed to some common cause ; and after careful inquiry Mr. Fosbroke discovered that all of the patients first attacked had attended a regatta held at Evesham on July 12th, and further, that they had all frequented a parti- cular meadow adjoining the river Avon. Still more ex- tended inquiry disclosed the fact that all these persons had partaken of " spirits, lemonade, or ices " while on the meadow, and that the water used either for diluting the spirits or manufacturing the lemonade and ices was ob- tained from a well which was subsequently found to be contaminated with sewage ; but whether specifically con- taminated was not quite clear, although suspicions strongly pointed in that direction. In any case, there is no doubt that the water from this well used for the manufacture of the lemonade was the cause of the outbreak, and subse- quently, by direct or indirect means, affected no less than 113 persons. (Mr. Fosbroke's Report for 1882.) But in country districts there occur many scattered cases of enteric fever, which, although they have a water origin, cannot be traced to specifically polluted water. According to my own experience, and it accords with that of many other health officers who have studied the etiology of enteric fever in rural districts, the disease is frequently produced by drinking water which is found to be polluted with animal matter, but not with specifically tainted matter. As regards these cases, the most careful inquiry has failed to discover any connecting link between them and pre-existing cases, while in all of them it has been found that the well-water has been polluted by leakage from some cesspool, privy, or drain. It may be Q 226 IMPURE WATER, said, therefore, that though they are essentially pythogenic, they are not specific. All this, however, will be discussed more fully in a subsequent chapter (see Chap. XIV.) 3. Diphtheria. Although .the etiology of this disease, especially as regards several recent outbreaks, has been by no means clearly established, there are grounds for believ- ing that it is frequently associated with polluted water. Certainly the majority of the sporadic cases which have come under my own notice have occurred at houses where polluted well-water was the only cause which could be discovered, and from the answers sent in reply to the circular issued in 1878 by the Society of Arts with refer- ence to our National Water Supply, it appears that there are a good many other medical officers of health who hold similar views. In an outbreak at Kirkella in Yorkshire, which was investigated on behalf of the Local Govern- ment Board by Dr. Blaxall, there was reason to believe that the water-supply of the school had been implicated in the causation of the disease, while other outbreaks have been instanced having a similar probable origin. 4. Dysentery. The instances of outbreaks of this disease which have been traced to the presence of animal impurities in drinking water are so numerous, especially in Eastern countries, that the mere mention of the fact will suffice. 5. Diarrhoea. In addition to outbreaks occasioned by direct sewage contamination, there are several recorded cases of the following description : In the Salford Jail there was a sudden outbreak of diarrhoea of a choleraic type, which affected 57 per cent of the prisoners, while of the officers and their families, who were distributed throughout the building, not one was attacked. The food of the prisoners was examined and found to be good ; it was evident also that the air did not contain the cause of the disease, for both classes were under the same conditions AND ITS EFFECTS ON PUBLIC HEALTH. 227 in that respect; suspicion was therefore directed to the drinking water. It was then discovered that, though the water supplying all parts of the prison was derived from the same source, there was one cistern for the use of the officers, and another covered cistern to supply the prison- ers, and that the untrapped overflow-pipe of the latter communicated with an open sewer. On the day of the outbreak the water from this cistern was observed to be coloured, and to taste unpleasantly. It had obviously absorbed sewer-gas, which had ascended through the over- flow-pipe ; and that this had been the real cause of the disease was confirmed by the fact that the outbreak dis- appeared almost as rapidly as it commenced, when the cistern was emptied and the pipe efficiently trapped. (Second Report of the Medical Officer of the Privy Council.) According to my own experience, much of the diarrhoea which prevails in country districts during the summer and autumn amongst children is due to polluted water drunk either as it is drawn from the well or when mixed with milk. Concluding Remarks. Although an attempt has thus been made to classify roughly the hurtful impurities of water, and the diseases which they may severally produce, it need hardly be said that in the great majority of in- stances of faulty sanitation connected with water-supply, there is often a combination of impurities and of diseases both. For example, the analysis of waters which have proved to be decidedly injurious shows that in general the impurities are numerous ; and, on the other hand, not one but several diseases may be either directly produced or indirectly influenced by them. And this difficulty of apportioning to special impurities their special effects is frequently increased by the presence of other causes of disease. Thus, the water may not only be polluted, but the supply may be scanty ; and thereby give rise to great 228 IMPURE WATER, ETC. want of cleanliness of the person, of clothes, of cooking utensils, and of the general surroundings ; while over- crowding, defective sewage - removal, badly ventilated drains, and other causes of disease, may also co-operate in seriously affecting the health of a community and largely increasing the death-rate. Amongst other diseases which have frequently a water origin may be mentioned ulcerated sore throat, low fever, and erysipelas. Indeed, in purely country districts what is known as low fever is essentially a filth fever, and is found to be produced in the great majority of instances by polluted well-water. It would also appear that the prevalence of calculous disease and gravel bears some relation to the amount of lime and magnesian salts contained in the drinking-water of certain parts of the country. This disputed subject has been carefully investigated by Dr. Murray of Newcastle- upon-Tyne (Brit. Med. Journal, 1872); and his state- ments, together with the cases which he adduces, are strongly corroborative of this view, but general statistical evidence is wanting. Finally, it has to be noted that several of the entozoa find their way into the body through the agency of drink- ing-water, as for instance the BothriocepJialus latus and the Ascaris lumbricoides. The latter, which is known as the round worm, I have found to be common in districts where the water-supply is chiefly obtained from shallow dip wells. DWELLINGS. 229 CHAPTEK IX. y DWELLINGS. THE vast importance attaching to the sanitary conditions of dwellings has already been frequently alluded to in previous chapters. Diseases arising from unhealthy site, from insufficient ventilation or overcrowding, from tainted or stinted water-supply, from defective drainage, or from accumulations of filth, are all of them associated with habitations which are faulty in their situation, construc- tion, or management. SECTION I. SITE. In choosing a site, special attention should be paid to the nature of the soil and the general conformation of the ground. Soils in order of healthiness may be approxi- mately classed as follows : Those overlying the primitive rocks, clay slate, millstone grit and oolite, gravel and loose sands, chalk, sandstone, limestone, and clays. The soil, if not dry, should be drained, and all hollows wherein water is likely to lodge should be avoided. For these and other reasons, the best situation for a house is on rising ground, with trees in the immediate neighbourhood, but not so close as to interfere with the free movement of the surrounding air. The aspect will very likely be influenced in great measure by the view to be obtained from the front windows, but it is preferable that a house should 230 DWELLINGS. face east or south-east, because in the morning the rays of the sun penetrate to the front rooms, and in the after- noon they cheer those at the back. "When, on the other hand, a house faces south, the front rooms are over- heated in summer by the rays of the noontide sun, while those at the back are deprived altogether of sunlight. Further, it is very essential in country districts that it be first ascertained that a good supply of wholesome water is procurable, and that there are no difficulties in respect to efficient drainage. If the subsoil is at all damp, it should be drained by suitable earthenware field-pipes, but care should be taken not to connect with house drains unless under strict precautions as to disconnection and ventilation. In towns, a great evil sometimes arises from building on rubbish containing vegetable matter which has been used to fill up the excavations made in brickmaking. Thus, in 1872, Mr. Crossby reported that the high rate of mortality in Leicester during the autumnal months was chiefly due to an annual visitation of infantile diarrhoea which prevailed in parts of the town built on such refuse ; and he distinctly attributed the disease to this cause. It is also worthy of special notice that this opinion has since been fully corroborated by the very elaborate and painstaking report presented by Dr. Buck and Mr. Franklin on the epidemic of diarrhoea which prevailed in that town during the summer and autumn of 1875. Further, the evidence of Drs. Parkes and Sanderson, in their valuable report on the sanitary condition of Liver- pool, though negative as regards the effects of cinder- refuse on the health of the occupants of houses built upon it, clearly points to the conclusion that such a soil is objectionable, at any rate when first laid down. With regard to this point they advised the Town-Council to adopt the following rules : DWELLINGS. 231 " 1. No excavation should be used for the reception of cinder -refuse unless it is efficiently drained. This appears to us to be of especial importance in relation to the filling up of brickfields. It is well known that the whole of the surface of clay is never removed, and there is always sufficient to form an impermeable basin, in which, in the absence of drainage, water constantly col- lects. We hold it to be of the greatest importance for the rapid decomposition of whatever offensive material may exist in the ' cinder/ that it should be able to become dry. The only way in which this can be promoted or secured is by efficient subsoil drainage. "2. As the vegetable and animal matter contained in the cinder -refuse decays and disappears in about three years, and is virtually innocuous before that time, we recommend that places filled up with cinder -refuse shall not be built upon for at least two years from the date of last deposit.'" They also advised that road - scrapings should not be mixed with the cinder -refuse, and that the scavenging department should be more careful with regard to the selection of material. It need hardly be said that wells sunk in made-up soils of this description can only yield a water which is highly polluted and altogether unfit for use. SECTION II. STRUCTURAL ARRANGEMENTS. In building on a site which has already been occu- pied, great care should be taken to make a thorough examination of the ground, so that no cesspits, rubble drains, or old wells, may escape notice. Every old drain should be taken up, all removable filth cleared away, and every pit thoroughly cleaned out and filled in with con- crete. 232 DWELLINGS. Unless absolutely necessary, no drain should traverse the basement of a house; and when it is necessary, as when houses are joined together in streets or squares, every such drain should be made absolutely air and water jight. Pipes of glazed earthenware are best suited for the purpose, and should not be less than four inches in diameter. They should be laid on a bed of concrete made with ground lime or cement, securely jointed, and covered with concrete. They should also be provided with full means of ventilation at either side of the basement. When they pass through foundation walls it is advisable that relieving arches should be turned over them, because it often happens that they become broken by settlements, or during the consequent underpinning. Outside the build- ing the pipes should be laid in a water-tight trench of clay puddle or concrete, and should lie their full diameters below the subsoil of the basement, in order that the lowest parts of the house may be efficiently drained. According to the new model by-laws of the Local Government Board, provision should be made for at least two untrapped openings to the house-drains, so as to ensure the constant flow of a current of fresh air through them. One such opening should communicate with the drains by means of a suitable pipe, shaft, or disconnecting chamber, and be situated as near as may be practicable to the trap, which should be provided between the main drain and the sewer. This trap is generally a syphon trap, and the ventilating opening, whether pipe, shaft, or simple cham- ber, should be situated on that side of the trap which is nearer the building. The second opening is to be provided by a vertical pipe or shaft, at least four inches in diameter, situated as far distant from the other opening as possible that is, at the upper extremity of the drain and carried to a height of at least ten feet, but so as to avoid the risk of discharging any sewer air into any window of the house DWELLINGS. 233 or adjoining building. When the soil-pipe enters the drain at the farther end, it will fully answer the purpose of this second ventilator, as shown at B in Fig. 5. Instead of the open grating at A, a ventilating pipe or shaft may WASTE PIPE FROM SAFE UNDER BATH Fig. 5. (After ROGERS FIELD, M. Inst. C.E.) be provided, as when houses abut on a street, but in either case facilities are thus afforded for the passage of a constant current of fresh air through the entire length of house-drain, and the entrance of sewer air into the house 234 DWELLINGS. is rendered practically impossible. Fig. 5 also shows the arrangements for overflow from cistern, and disconnection of pipes from sink and bath. To facilitate inspection, the outside track should be provided, at suitable intervals, with access pipes or man- holes. These are of various patterns, but all of them permit an easy opening into the drain, so that deposits or obstructions can be readily removed. To prevent the formation of such deposits, all house -drains should be regularly flushed, and it is a very good plan to provide an automatic flushing tank at the extreme end of the house- drain, wiiich could be charged with slops from the sink, or water from a bath. (For further particulars, see Chapter XL, on Eemoval of Sewage.) Doulton's patent grease interceptor (see Fig. 6), which is intended to receive sink-slops, makes an excellent auto- matic flush-tank. It is constructed to hold 12 gallons, Fig. 6. is 1 foot 6 inches in diameter and 1 foot 6 inches high, and comparatively cheap. Where a cesspool is required to receive the sewage of a country house provided with water-closets, it should be DWELLINGS. 235 situated at a safe distance from the building, made per- fectly water -tight, and be abundantly ventilated. The plan of construction should be on the liquid-manure tank principle, the walls being of brickwork set in cement, surrounded by a clay puddle, and lined inside with a coating of cement. Both roof and bottom should be arched, the roof provided with a manhole, and the bottom built with a fall towards one end, where a pump could be fixed. The depth should not exceed 6 or 7 feet, other- wise the increased hydrostatic pressure would necessitate expensive walling. To separate the solids from the liquids a galvanised iron wire diaphragm or grating should divide the tank into two parts. All cesspools should be regularly and frequently cleaned out, and it is of the utmost import- ance that the drains should be trapped and disconnected, and the soil-pipe ventilated. If the cesspool is situated in a field or orchard some distance from the house, the liquid contents can frequently be got rid of by construct- ing an overflow pipe leading into sub -irrigation drains, either with or without a flush-tank. (See Chapter XL) If the water-supply is to be derived from a well, the well and cesspool should be widely separated. In case of accidental leakage it is also necessary that the well should not be near the house-drains. To exclude subsoil water, the upper part of a well should be clay-puddled, or made otherwise water-tight, and the mouth should be protected against the entrance of surface-water. Every well should be ventilated and provided with a manhole for purposes of inspection and cleansing. After having secured dryness and healthiness of sub- soil, the next point of importance which has to be kept in view is the isolation of the area upon which the proposed dwelling is to be erected from the subsoil, and this can be effected in the cheapest and best way by using concrete. In order to prevent damp from rising into the walls, a 236 DWELLINGS. damp-proof course should overlay the whole of the founda- tions. Two or three courses of slate laid in the best cement will answer the purpose, or, if external symmetry in the damp-proof course be made a desideratum, tiles made of highly vitrified stoneware should be employed. When there is a basement story, it should be isolated from the ground by an open space. The entrance of underground damp may also be prevented by constructing what are called dry areas ; that is, by leaving a space between the main wall and a thin outer wall, which reaches to the ground level, the two being joined together here and there by stretching bricks. As much of the dampness in walls is due to driving wet, well-planned houses are now often built with hollow walls, in which case ties or bonding bricks must be laid in at regular intervals, to render the strength and stability of the twin walls equivalent to a strong single wall. With single walls, built of soft porous material, the effects of driving wet may be obviated by slating or tiling them, or by applying to the outer surface one or other of the several patent waterproof compositions which are well recommended. Perforated bricks should be introduced at suitable distances in the outward walls, to admit air to the joists and beneath the flooring. One of the gravest faults in the construction of even the better class of houses in the present day is the little attention which is paid to the position and arrangements of water-closets. They are too frequently situated in out-of-the-way corners, where only borrowed light can be obtained, and efficient ventilation is impossible. The best position is in an isolated block, built tower fashion, and abutting against the outer wall of the house, with a closet on each floor and the supply cistern on the top. There should be an anteroom or passage between each closet and DWELLINGS. 237 the house, large enough to admit of sufficient cross ven- tilation by means of open windows, or windows provided with ventilating panes. A double set of doors would be required, one leading into the house and the other cutting off the passage from the closet. The closet-seat should face a window in the outer wall, so that abundance of light may be secured for inspection with regard to cleanliness, and direct draught from the window be avoided. The window should extend up to the ceiling, and have double sashes. The closet may be permanently ventilated by keeping the top sash drawn down, or by air-bricks inserted immediately beneath the ceiling. In smaller-sized houses the closet may be simply projected from the build- ing, with the seat facing the door, and with two opposite windows reaching to the ceiling between the seat and door. Cross ventilation and sufficient light would thus be ob- tained, without the interposition of an anteroom. All, however, that is insisted on in the model by-laws of the Local Government Board is, that the closet should be built against an outside wall, and be properly lighted and venti- lated. There are so many kinds of closets, well arranged in all their details, that it is difficult to say which of them are most to be recommended. There are others, again, such as the round hopper closet-pan, fixed into an ordinary sigmoidal bend, which cannot be sufficiently condemned, unless worked by a very high pressure of water ; they are constantly getting foul, and it is seldom that the whole of the excreta are removed ; indeed, they can seldom be kept clean unless they are regularly flushed by a bucket or pail. Generally speaking, those closets are the best which provide for good flushing and rapid and complete removal of the excreta, without permitting reflux of foul air. Every closet, unless it be flushed by hand, should be provided with a cistern, preferably of the waste-preventing 238 DWELLINGS. kind, because it is of the utmost importance that there should be no direct communication with the water-main. It has also to be pointed out that the closet should not be supplied from the same cistern which supplies the drinking water. The pan should be roomy arid made of white glazed earthenware ; the machinery should work easily and not be apt to get out of gear ; and the seat should be so framed as to come asunder readily to permit of inspection. ~No closets should be constructed with either a " container " or a D-trap, because both retain filth, and thus become a source of danger. Amongst closets which have been highly commended may be mentioned thie " Excelsior Water-Closet ;" Banner's Closet ; Winn's Closet ; Dodd's Closet ; Bean's Household Closet ; and Twyford's National Closet. As soil-pipes communicate directly with the drains, they should be carried up to the highest part of the roof, and be of the same diameter throughout. Efficient venti- lation of the drains is in this way secured at a most important point, and the pipe from the closet trap can be connected with the soil-pipe without interfering with the upward current of sewer-air. If the soil-pipe cannot be carried straight up to the top of the house, the bends or angles should be made as obtuse as possible, and in any case it should not be plastered or built into the wall, but ]eft free for inspection throughout its whole track. It is obvious that, were this plan universally adopted, there could be no pressure of sewer-gas against the closet trap, and therefore little or no risk of its entering into the house by this channel. The waste-pipe from a house- maid's sink, intended to carry off foul matter, should be constructed and ventilated like a soil-pipe. // It has been urged, by way of objection against this plan, that, where houses are closely packed together, and are of different elevations, the sewer-gases discharged from DWELLINGS. 239 the pipes of the lower houses would find their way into the "higher, and thus become not only a nuisance but a source of danger. With ample sewer-ventilation, however, the objection does not hold good, because the sewer air is so diluted as to be inoffensive and comparatively pure. With regard to all other pipes, whether waste-water // pipes, sink-pipes, or pipes from lavatories, it should be laid down as a rule that none of them should lead directly into any soil-pipe or drain. They should be carried out- side an external wall, and discharge in the open air over a channel leading to a trapped gully grating at least 18 inches distant. (See Fig. 5.) But although the sewer- gases are in this way prevented from entering the house, it is still necessary that the sink and other pipes should be trapped. Scullery and sink pipes, for example, will require article-intercepting traps, and pipes to lavatories or baths must be provided with syphon traps to prevent the ingress of cold air. (See Fig, 5.) All traps on house-drains should be ventilated either by pipes carried to the roof or parapet of the house, or by what is called direct ventilation. Unless protected in some such way they are comparatively useless. (See Chap. XL) When a water-closet is dispensed with, some form of dry or pail closet situated outside, and at a safe distance from the well (if any) should be provided. Details concerning the ventilation and warming of a house have already been given in Chapter IV., and the only points which need be repeated are the importance of constructing a separate extraction flue for each room in the chimney-stalk, the desirability of inserting venti- lating fire-places, and the great advantage of securing that the products of gas-combustion be conveyed by special channels into the outer air. It is needless to say that the rooms in a well-con- structed and healthy house should be spacious, airy, and 240 DWELLINGS. light: < The windows should reach to within a short dis- tance of the ceiling, and should always be made to open. It is preferable to have them glazed with plate glass, to economise heat. No single bedroom should be of less dimensions than 1000 cubic feet, nor should any bed- stead be fixed in a recess. SECTION III. DWELLINGS FOE THE POORER CLASSES. In constructing buildings for the poorer classes, the great difficulty, encountered at the very outset, consists in providing the necessary accommodation with the requisite sanitary arrangements, at a cost which will allow of a sufficiently low rental. In towns the original cost is greatly increased by the high price of land ; but even in country places, where a site can be procured at a cheap rate, the cost for the erection of a cottage of the humblest pretensions will entail a rental which many a labouring man can barely meet. Where the ground rental is low, the cheapest and most commodious form of labourer's cottage is one without any upper story. Thus, according to Mr. Allen, in his manual on Cottage Building, a cottage consisting of a living-room for general every-day use, a bed- room for the labourer and his wife, a bedroom for boys, a bedroom for girls, a small wash-house, a store-room and closet, could be built for 100, provided all the rooms are on the ground-floor, and that two such cottages be ranged side by side, so as to be spanned by the same roof, and con- tained within four walls, forming a simple parallelogram. The row of cottages proposed by Dr. Hunter in the Seventh Eeport of the Medical Officer to the Privy Council, pro- vided for a front and back kitchen in each cottage, and two bedrooms overhead. The kitchens were to be paved with brick or tile, "the front about 11 feet by 11, by 8 feet 6 inches high ; the back about 1 1 by 8 feet 6 inches. DWELLINGS. 241 Ceiling would be unnecessary. There should be five doors only, the closet under the stairs one, each bedroom one, and two house doors. There should be four sliding win- dows, a grate with an oven, a boiler in the back kitchen, a little fireplace in one bedroom, and a Welsh slate roof, the bedrooms being ceiled. " Such houses might be supplied for 50, or 1500 for the thirty." In a paper read before the Farmers' Club in 1874, Mr. Howard of Bedford states that, some few years pre- viously, he built a block of six cottages for his labourers entirely of concrete. The walls were a foot thick, and in consequence of the impervious nature of the material they were warmer and drier than ordinary brickwork. Each cottage contained three bedrooms, and each was provided with an earth-closet at the end, but accessible from within. Exclusive of the closets, the cost of the whole block was a little over 600, or 100 per cottage. According to the design by Mr. Birch, which obtained the award of the Society of Arts in 1864 for premiums offered by Mr. Bailey Denton, the estimated cost of a pair of cottages was 203, including every requisite necessary to render them complete and fit for occupation. On the ground -floor it was proposed that there should be a living- room 12 feet 6 in. by 12 feet; a scullery, containing a copper for washing and a sink, 10 feet 5 in. by 7 feet 6 in. ; and a small pantry and place for fuel opening into the scullery. On the chamber floor there were to be three bedrooms with a floor-space respectively of 12 feet 8 in. by 8 feet 6 in. ; 7 feet 8 in. by 8 feet 6 in. ; and 9 feet by 8 feet. (See -Builder, 1864.) Owing to the increased cost of materials and the rise in wages, it is very likely that the above estimates would be found to be somewhat too low for the erection of similar cottages in the present day, but if built in blocks R 242 DWELLINGS. or pairs, I am credibly informed that good cottages with three bedrooms can still be erected for about 100. In these plans, and in fact in almost all plans for cottage construction, the cubic space allowance is very limited, so that overcrowding, to a greater or less extent, is sure to prevail at times. Cottages which are scarcely roomy enough for a married couple and two or three children become occupied by much larger families, or the family increases in number year after year, while the bed- room accommodation remains the same. The initial space, therefore, should be ample enough to meet the require- ments of, at any rate, moderate family increase ; and when a number of such cottages are built in the same locality, they should be of different sizes, to suit small and large families alike. The kind of closet best suited for country cottages is some modification of the dry system, while the slops, if they do not discharge into village drains, should be utilised in the garden, or disposed of by subsoil irriga- tion where that is possible. All this, however, will be discussed more fully in Chapter XI. In large towns the house accommodation for the labouring classes must necessarily be supplied in a great measure by what are called tenements, but in this case special attention should be paid to sanitary arrangements, such as closet accommodation, water-supply, ventilation, and general cleanliness of premises, and a copy of rules or by-laws should be prepared and handed to each occu- pant. Of equal importance with the construction of dwell- ings for the labouring classes is the far more difficult problem of repairing and improving the unhealthy abodes which, in town and country village alike, increase the annual rate of mortality to an extent that can hardly be estimated. It is true that the law already prohibits the inhabitation of the worst class of dwellings, such as damp, DWELLINGS. 243 dark, underground cellars ; but there are other dwellings, so numerous that their immediate demolition would deprive a large proportion of the lower classes of shelter, which no alterations or improvements can render healthy. They are either situated in narrow, dingy alleys, or huddled together in close courts, so as to be practically unventil- able, or their internal condition and constructural faults are so grave as to be beyond remedy. Nor are these the only sanitary defects connected with them which have to be condemned. It is in these very dwellings that the filth and poisonous effluvia due to overcrowding are con- stantly accumulating, and where the germs of disease find a fitting soil for their development. The departmental reports of the Privy Council afford numerous instances of such a state of things, and notably those of Drs. Hunter, Stevens, and Buchanan. It is to be hoped that the carrying out of the provi- sions of the Artisans' Dwellings Act of 1875 and 1882, or some similar measure, will eventually bring about a marked improvement in this respect in many of our cities and large towns, for hitherto the difficulty of dealing with what is called " surface-crowding " has thrown great obstacles in the way of reaping to the full extent the advantages to be gained from lessening the indoor over- crowding. In the worst parts of Liverpool, according to ^ Drs. Parkes and Sanderson, nearly 1000 persons are huddled together in one acre of ground, and in other towns, such as Glasgow and Greenock, the number per acre in some districts is quite as great. It is clear, there- fore, that no improvement in the dwellings, nor any in- crease in the amount of cubic space per head, will render the ventilation as satisfactory as it should be, when so many houses are packed together in such a limited space. Demolition of old houses, the displacement of the popula- tion into blocks of model dwellings, or into houses put 244 DWELLINGS. into serviceable repair, and the opening of new streets, are all necessary. As instances of successful enterprise in this direction, it may be mentioned that the London Improved In- dustrial Dwellings Company now provides house-accom- modation for over 20,000 persons, and that during 1881 the death-rate averaged only 16 '4 per 1000; while the Peabody Trust has provided accommodation for about 12,000 persons, and during the same year the death-rate averaged 17 '2 per 1000 as against 21 '2 for London generally. In country districts, where there is far less excuse for the existence of these evils, it has been found that in reality they are almost as glaring and wide-spread as in towns. The elaborate report of Dr. Hunter on the State of the Dwellings of Eural Labourers (see Seventh Report of Medical Officer of Privy Council) may be quoted in proof of this statement. In all, 5375 cottages were reported upon. Of these, 2195 contained only one bed- room ; 2930 contained two ; and only 250 more than two. The number of persons resident in them, including adults and children, was 24,770, giving an average of 4' 6 persons to a house, or 2*8 to a bedroom. In the single- bedroomed houses, the average number sleeping in the bedroom was 4, 2 '2 of whom were adults and 1/8 child- ren. The average cubic space for sleeping accommo- dation was estimated at 156 feet per head. The rickety state of the great majority of the hovels permitted a freer interchange of air than in the new cottages, so that, although the cubic space per head in the latter was some- what larger, the contained air was generally more impure. Indeed, many of the bedrooms were so much exposed to the weather, that cases of sickness, when they did occur, had to be treated in the kitchen. But the wretched sanitary condition of the dwellings was even a less evil DWELLINGS. 245 than their numerical insufficiency. It was found that many landlords pulled down the cots on their estates when they fell into decay, without providing others, and thus forced the labourers to find house-room in already over- crowded hamlets. As a consequence, this huddling to- gether of human beings not only presented numerous foci for the development of disease, but rendered the limita- tion of any contagious diseases which were introduced an almost hopeless task. That such a state of things con- tinues to exist in many rural districts the reports of medical officers of health from all parts of the country show but too clearly, and though there can be no doubt that the improvements which have been carried out in various districts since the passing of the Public Health Act of 1872 have been very considerable, it is impossible to cope with the innumerable evils connected with defec- tive house-accommodation in small towns and country villages until larger legislative powers are conceded. As I have stated elsewhere, I am strongly of opinion that some measure akin to the recent Artisans' Dwellings Act is urgently required for rural and small urban districts. " Let this legislative necessity be advocated as warmly as it has hitherto been tacitly admitted, and there will be no difficulty in drawing up a bill which, without unfairly interfering with the rights of private property, will give a wholesome stimulus to the discharge of public obligations ; afford the requisite scope for individual or conjoint enter- prise in adapting old cottages and in building new ones where they are required ; and, above all, empower and impose it as a duty on sanitary authorities, which cannot be evaded, that they themselves shall carry out the neces- sary improvements in localities where private or conjoint enterprise, aided if you like by philanthropic effort, may prove inadequate, or where public obligations on the. part of landowners are in this respect persistently neglected. 246 DWELLINGS. But it has been urged that individual or conjoint enter- prise will' fail to be elicited because cottage property does not pay a sufficient percentage on the outlay. Well, I am quite willing to admit that what are called ornamental cottages may not pay, but ornamental cottages are need- lessly expensive, and are built under exceptional circum- stances. What I do know is this, that substantial and comfortable cottages can be built in pairs or in blocks, each containing three bedrooms, at a cost of about 100 per cottage. Then, again, it is very well known that the worst class of cottages, when they get into the hands of small property owners, often pay as much as ten to fifteen per cent on their outlay ; so that, taking into consideration the improved and improving position of the labourer to pay a better rental, the fair return that may even now be obtained for new cottages, and the comparatively large return which is obtained for all cottages after being put into habitable repair, there is every reason to believe that there will be no lack of private or public enterprise in the shape of local building and improving societies, pro- vided only the requisite facilities for such enterprise be legalised by Act of Parliament." (See the Author's pamphlet on Sanitary Defects in Enrol Districts, and How to Remedy them, and Dr. Bond's Home of the Agricultural Labourer.) Unfortunately, too, many of the evils connected with house-accommodation in rural districts threaten to become perpetuated, inasmuch as rural sanitary authorities, unless they apply specially for urban powers, have no control over the erection of new buildings. Similar by-laws should be in force with respect to thickness of walls, height of rooms, ventilation, drainage, and general sanitary arrangements which are carried out in urban districts. Indeed, it is difficult to conceive why such control should not have been conceded to sanitary authorities without DWELLINGS. 247 distinction, unless it be that sanitary legislation has hitherto been halting and one-sided. It is quite true that many sanitary defects connected with existing cottages can be dealt with under the wide term nuisance, such as the repair of uneven floors, and roofs that let in the rain ; the repair of dilapidated walls ; the opening of closed windows; the removal of privies and pig-styes which abut against outside walls ; the drying of the sub- soil ; the repair of drains ; and the like. It is likewise true that if a house cannot be put into fairly habitable repair the law gives power to close it ; but where houses are scarce, it need hardly be said that this becomes a very serious matter, inasmuch as it either tends to increase the overcrowding elsewhere, or leads to displacement of labourers and their families, an alternative which is attended at all times with much inconvenience, and very frequently with great hardship. In large towns this displacement of the population becomes a question which naturally affects the poorer classes to a much greater extent than in country villages. Many extensive undertakings, such as the construction of railways and new streets, while they act beneficially in making wide clearances in the crowded districts, almost of necessity conduce to overcrowding in neighbouring parts. The families that are thus rendered homeless by the demolition of their dwellings seek the nearest shelter, rents are raised in consequence of the increased demand for accommodation, and such as cannot afford to expend more than they did previously must be contented with homes even less healthy than those which they have been compelled to leave. As a compensating measure, the running of working men's trains morning and evening, between the suburbs and the town stations, although it is a step in the right direction, does not by any means meet the difficulty. Larger measures are undoubtedly 248 DWELLINGS. required, and the more thoughtful amongst sanitary re- formers are agreed in maintaining that no parliamentary powers, permitting the demolition of numerous dwellings in populous districts, should be granted unless the com- panies or corporations applying for these powers provide commensurate and improved accommodation elsewhere, and within reasonable distances. It is true that many of the displaced population might not choose to remove to the new dwellings, but they should have the option. Tenants, at all events, would not be wanting, and that there would be no financial loss is clearly proved by the profits gained by private enterprise in building homes for the working- classes, although it must be admitted that numbers of such houses, as they are run up in the present day, can scarcely be pronounced habitable. Urban sanitary autho- rities have, however, full powers vested in them by the statutes to prevent the erection of dwellings that are unwholesome, and it is their duty to see that the accom- modation and structural .arrangements are in all cases satisfactory. Concerning the duties of the medical officer of health with regard to overcrowding and places unfit for habita- tion, together with the sanitary enactments dealing with the same, see Chapter XVI. . SECTION IV. SANITARY INSPECTION OF DWELLINGS. 1. Diseases traceable to Sanitary Defects. There are so many diseases, and some of them so fatal, associated with sanitary defects in or around dwell- ings, that it is of the utmost importance that every medical practitioner, and above all every sanitary official, should be able to detect these hidden dangers, or direct how they may be discovered and remedied. Exclusive of new houses, which have been erected in accordance with DWELLINGS. 249 well-devised by-laws, it is no exaggeration to say that in the vast majority of houses, and especially good-class houses, sanitary defects may be found which at any time may lead to the gravest consequences, and when disease does break out the wonder often is that the inmates should have escaped so long. Minor disorders, such as languor, headache, so-called bilious attacks, dyspepsia, diarrhoea, and slight ulcerated sore throat, are frequently allowed to pass unheeded, or are treated as ordinary ailments ; and it is not till disease of more pronounced severity occurs that the sanitary condition of the house becomes suspected, and the real cause is discovered. Apart from ailments which are connected with damp- ness of site, foundations, or of walls, such as rheumatism, phthisis, bronchitis, or other lung affections, the class of diseases which are associated with faulty house sanitation are essentially filth diseases, wh ether they originate de novo or are conveyed by befouled air or water. And among these diseases may be enumerated the following : diphtheria, ulcerated sore throat, follicular tonsillitis, follicular stomatitis, croup, enteric and ill-defined forms of fever, diarrhoea and dysentery, erysipelas, carbuncle, abscess, pyaemia, hospital gangrene, and puerperal fever. There is no doubt, too, that the breathing of vitiated air, whether depending upon overcrowding, defective ventilation, or the entrance of sewer gas, not only induces phthisis, pneumonia, and other lung affections, but largely influences the spread of zymotic disease and the severity of all kinds of diseases, however they may have been originated in the first instance. Pneu- monia, is frequently engendered by impure air, and it is now generally admitted that this filth-pneumonia, as it may be called, is infectious, and occasionally becomes epidemic. Then, again, there can be little doubt that it is this influence which changes pleurisy into empyema, 250 DWELLINGS. simple bronchitis into broncho -pneumonia, and which serves to explain the frequency with which lung affec- tions are associated with various infectious diseases, such as smallpox, measles, whooping-cough, and enteric fever. 2. Sanitary Defects in and around dwellings. As regards the defects themselves, they are of every variety and extent, and many of them palpable enough. Damp foundations, damp walls, imperfect ventilation, windows not made to open, roofs dilapidated and out of repair, floors uneven, general uncleanliness, overcrowding all these constitute nuisances which are especially common in the dwellings of the poorer classes in town and country districts alike. Then, if there is no sink inside the dwelling, there is generally a drain near the front or back door to remove the slops, which is so badly laid and trapped that foul smells are constantly given off, and these are often aggravated by other nuisances. In country districts, for example, pig -styes, byres, and manure -heaps are frequently so close to the dwellings that the inside air is always more or less tainted. The closet accommodation, again, consists either of a foul privy, which, though sufficiently far removed, is so offen- sive that it cannot be used without risk, or of a privy and deep ash-pit close to the house and in dangerous proximity to the well. Indeed, pollution of the well- water from closets, leaky drains, or manure-pits in farm- yards, is the principal cause of the majority of the spor- adic cases of enteric fever which are met with in country districts, and of much of the diarrhoea which becomes more or less prevalent during dry and warm seasons. Apart from overcrowding, then, it may be said that the gravest dangers to health connected with the dwellings of the poorer classes in rural and small urban districts are external rather than internal, and therefore it is essential that in making a systematic inspection of such DWELLINGS. 251 premises special attention should be paid to the surround- ings. The points to be noted on a detailed inspection are the following : Date of inspection ; name or situation of house ; name of owner and occupier ; number of in- mates ; number of lodgers, if any ; number of living- rooms and sleeping -rooms (if overcrowding is suspected, the cubic space of the sleeping -rooms should be ascer- tained see Chapter XVI.) ; state of ventilation (note whether all windows are made to open, and whether every sleeping-room not provided with a fire-place has a ventilating opening of some sort in addition to window) ; condition of floors (whether they are uneven or out of repair) ; condition of walls (whether damp or dilapidated) ; condition of roof (whether it lets in the wet) ; general condition of premises (whether clean and in good repair) ; condition of drainage (if any drain enters the house, note whether it is properly disconnected, also note whether outside drains are well laid and properly trapped) ; nature of water-supply (if from a well, note whether there are any sources of pollution near, such as deep ash-pit, privy, cesspool of any kind, leaky drain, or manure-pit if water is suspected, have it analysed) ; nature, situation, and condition of closet accommodation (note whether closet is free from nuisance, whether there is a deep ash- pit in connection with it, whether, if not a pail-closet, it is situated at a safe distance from house or well, etc.) ; other nuisances (such as keeping of pigs too near dwell- ings, pig-wash cisterns, manure-heaps, etc.) A detailed examination of all these various items is of course not necessary in the great majority of cases, but in making a systematic survey of a district it is essential that they should be noted in the survey -book (see Chapter XVI.) With regard to country mansions and the better class country houses, the dangers to health, if not more 252 DWELLINGS. numerous, are certainly more serious, and for the most part are connected with the drainage or water-supply. Indeed, it is no exaggeration to say that grave sanitary defects will be found to exist in almost every country residence which has not been built or inspected within the last few years ; and even in respect to new buildings it is lamentable to find that, owing to ignorance or neglect on the part of architect, contractor, or plumber, and sometimes of all three, the most serious blunders are still perpetrated. One of the chief dangers in country houses attaches to the cesspool and the drains leading to it. The cess- pool itself is generally some distance from the house, and is provided with an overflow which discharges into the nearest ditch or brook. It is rarely ventilated, but is usually completely covered up, and in any case is only cleaned out at long intervals, sometimes not for periods of years. The drains are either rubble drains, sometimes huge brick culverts, or common tile drains ; but, whatever their exact structure, they permit of free deposit, and are neither efficiently trapped nor ventilated. In close prox- imity to the walls, and sometimes under the floors, there are frequently supplementary cesspools or catch-pits, in- tended to retain solid matters, which are kept covered up with close-fitting slabs, and are so seldom opened and cleaned out that their very existence becomes forgotten. Into this system of drainage are discharged directly the pipes from sinks and sculleries, the overflow pipes from baths, the drains from cellars, the soil pipes from water- closets, and very often the rain-water pipes. The water-closets are generally situated somewhere in the centre of the house, badly lighted, badly constructed, and without proper ventilation. The soil-pipes are un- ventilated, and very soon become decayed and perforated. Very often the cistern supplying the closet is filled by DWELLINGS. 253 means of a force-pump ; and the same cistern, which is rarely cleaned out, and from which there is an overflow- pipe leading direct into the soil pipe, also supplies the water for drinking and cooking purposes. In addition to all these sources of danger, the well itself may be close to one of these leaky drains or cesspools, or it may be near some outside offices of the worst form of privy or midden ash-pit, so that in any case it is constantly exposed to the risks of pollution. In town houses of old construction the dangers to health are similar, though perhaps not so grave, inasmuch as the water used for domestic purposes is usually ob- tained from a public supply. But even this may become contaminated in the house -cistern if the overflow pipe from the cistern, as often happens, discharges directly into the soil-pipe or the house-drain, or if the same cistern directly supplies the water-closet. The drains, for the most part, are laid underneath the house, and are often found to be constructed of brick, and generally so leaky that the sewage percolates into the soil. In houses in- fested with rats it may be taken for granted that the drains are brick drains, or at all events that they are of very faulty construction. Even when drain-pipes have been used, they are frequently so badly laid and jointed that soakage into the soil becomes constant, and the inside air of the house always more or less contaminated. The closets, again, are generally of faulty pattern, and very improperly situated it may be, in the centre of the house, on the landing, or sometimes in the bedrooms themselves ; but in any case they are almost always badly lighted and ventilated. The soil-pipes, as in country houses, are usually inside the house, often very leaky, and seldom ventilated, nor are any other means of ventilation pro- vided for the house-drains. Moreover, the waste-pipes from sinks, baths, and cisterns are seldom disconnected, 254 DWELLINGS. so that channels for the entrance of sewer-air are to be found on every floor of the house, but especially in the basement, where, in addition to the leakiness of the drains, there are openings into them for the purpose of washing down the floors or draining cellars. These drain inlets are a permanent source of danger, because the traps are often bell-traps, from which the water evaporates, leaving practically untrapped openings ; or if the water does not evaporate, the pressure of sewer-gas is so great that the water becomes saturated, and is constantly giving off foul emanations. Sometimes it happens that foul smells are detected in parts of a house where there are no drains or inside pipes discharging into them, and in these cases it is generally found that the foul air travels along rat runs, under floors, or behind skirtings ; or it may be conveyed along the pipes containing the bell- wires ; or it may find an entrance through the windows, from an adjacent rain- water pipe which is directly connected with the sewer. Of course foul smells in a house do not always indicate the entrance of sewer-air, but they should never be tolerated a single day until the cause is ascertained and removed. Sometimes they are caused by the decaying body of a dead rat or mouse under the flooring, by dry rot, or, in rare instances, they have been found to proceed from some filthy paste used in papering the walls ; but as a rule they point to defective drainage or escape of sewer-gas into some part of the house. 3. Mode of Inspection. In making a detailed exami- nation of the sanitary condition of a house, it is advisable that either an experienced builder, whose practical know- ledge can be relied upon, or a sanitary engineer, be called in ; and if there are plans of the house and drainage in existence, these should be obtained. In order to make the examination as thorough as possible, arrangements should be made to have the drains previously opened in DWELLINGS. 255 several places, and concealed pipes and other fittings ex- posed to view. If the main drain is found to pass under the house, and to be badly laid or constructed, the instruc- tions should be to have it taken up and relaid. Should it appear to be in good condition, it should then be tested as to its soundness, which is done by stopping it up at its lower end and filling it with water, and noting whether the water sinks or not, and at what rate. To test whether there are any deposits, a large volume of water should be poured down at the water-closet or sink, and if this appears foul and thick at the lower opening the drain is condemned as one of deposit. By noting the time which intervenes before the rush of water appears at the lower opening, an approximate idea may be obtained of the velocity of flow, or this may be determined with greater precision by pouring down some lime-water, and timing the flow. Leakages in the pipe tracks or elsewhere, for the escape of sewer -gas, may be detected by pouring down some oil of peppermint at the closet or sink, or blowing up at the opening made in the drain the smoke from burning brown paper. The next point which should be ascertained is, whether the house drain is disconnected ; and if there be a strong draught up the drain it shows that there is no intervening- trap. As already shown in the by-laws laid down for the drainage of new houses, this disconnection of the house drain by trapping, and providing a ventilating open- ing on the house side of the trap, is of the utmost im- portance, and it can readily be carried out in all cases, either by providing a ventilating pipe if the house is close to the street, or a simple open grating if there is sufficient space (see also Chap. XL) Before leaving the basement, all traps and branch drains should be carefully examined, and a careful search should be made for cesspools, if the existence of any is 256 DWELLINGS. suspected. The condition of the flooring should also be noted as to dryness or otherwise, and the ventilation of all parts of the premises should be inquired into. Any water-closet on the basement which is found to be in the centre of the building, or to abut against any inside wall, should be condemned. Such closets are badly lighted and ventilated, and the drains leading from them are usually very defective, and liable to be choked up. If there are no underground cellars or basement, inquiry should be made as to whether the space beneath the floors is sufficiently ventilated, and whether there are any signs of rot. The dust-bin or ash-pit, and any outside offices, should also be examined, and if the ash-pit is found to be large and deep, it should be filled up to the ground level. The details to which attention should next be directed are those connected with water-closets, sinks, baths, etc. If the closet is in the centre of the house, or abuts against an inside wall, there can be no doubt of the faultiness of the arrangement. But even when the closet abuts against an outer wall the soil-pipe generally leads down inside the house into the drain, and not infrequently is taken through cupboards or larders. The track of the pipe should be exposed to view, and its soundness tested, by means of filling it with water or by the smoke test ; but it is advisable to recommend, in any case, that the soil-pipe should be carried outside, and be ventilated by a pipe of the same dimensions extending to above the eaves. Small ventilating pipes, of about % in. or li> in. in diameter, are practically of little use, and often become choked up. The woodwork and fittings of the closet should next be examined, and auy overflow-pipe from the safe should be made to discharge outside. If the pipes from sinks, lava- tories, and baths are not disconnected and it is seldom found that they are, except it be in new houses instruc- DWELLINGS. 257 tions should be given to have all these pipes carried out- side the walls of the house, and made to discharge on to trapped gratings communicating with the drain. Kain- water pipes which are found to be directly connected with the drain should also be disconnected, and any found passing inside the house should be carried outside. The cisterns which supply the closets should next be examined, and it should be ascertained whether these supply the drinking water as well. If the water is stored in a large cistern under the roof, and is found to supply any taps, each closet supplied from this cistern should be provided with a small waste-preventing cistern, or steps should be taken to provide an independent supply for drinking and cooking directly from the main. The cistern itself should be examined as to cleanliness, and the overflow pipe, which is often found to lead directly into the soil-pipe, should be carried outside. In all houses provided with a public supply, the use of well water should be condemned, because, although it may be found to be fit for drinking purposes, the risk of pollution is always greatly increased in towns, on account of neighbouring drains and sewers. In country districts special attention should be directed to the water supply, and any deep ash-pits, midden-privies, or cesspools near wells should be removed, and the drains examined. If the water is pumped up by means of a force-pump into a cistern, for the purpose of supplying the closets, it will generally be found that the cistern also supplies the housemaid's sink, and that at this tap the water-bottles, as well as bedroom utensils, are usually filled. With regard to the alterations generally, it should be recommended that unless special automatic flushing arrangements are provided, the house drains should have a fall of at least one in thirty, and be at least 4 in., and never more than 6 in., in diameter. In cases where a 3 258 DWELLINGS. proper fall cannot be obtained, a small self-acting flushing tank, in connection with the sink, should be provided. If the house drains extend beyond the closets, the terminal end should be ventilated, as well as the soil-pipes, and no ventilating pipe should be less than 4 in. in diameter. Manholes should be placed at all bends in the drains so as to permit of ready inspection, and all down pipes should either be exposed to view, or, if encased, the casing should be made easily removable. Although much improvement has been made of late years in the sanitary arrangements of dwellings, it should be laid down as a rule by every tenant in search of a house, that he should have the sanitary condition carefully inquired into, and any defects removed, before he takes possession. In London, Edinburgh, Gloucester, and several other large towns, there are sanitary protection associa- tions which undertake such inspections, and repeat them at stated times for a fixed fee or subscription ; but it would be a wise policy on the part of sanitary authorities throughout the country to undertake these duties them- selves, and not limit their functions to the removal of actual nuisances, without interfering with many defects which only become declared nuisances when disease breaks out. HOSPITALS. 259 CHAPTEE X. HOSPITALS. IN large towns the position of every hospital must prim- arily depend on the distribution of the population, or part of the population, whose wants it is intended to relieve, and hence the choice with regard to site is often very limited. Apart, however, from this restriction, there are certain considerations which ought always to influence the selection of site. For example, the future hospital should be erected in as airy and open a space as can be obtained, preference being given either to the outskirts of towns or to their largest interior unoccupied spaces. According to the recommendations of the Chirurgical Society of Paris in 1864, a free area of not less than 540 superficial feet should be allowed for each patient. This would give an acre of ground for a hospital containing 80 beds. In this country, on the other hand, an acre for 100 patients has been held to be sufficient, but a good deal will depend on the size of the hospital. Any defect in salubrity of site must be compensated by increased floor and cubic space. No doubt, the most healthy site for a hospital is in the open country, with a dry and porous soil, and slightly raised above the plain to facilitate drainage, but even a stiff clayey 'soil can be made perfectly healthy if proper precautions be taken in asphalting or concreting the foundations, and in providing plenty of free ventilation 260 HOSPITALS. beneath the ground-floors. While shelter from the cold north-easterly winds is desirable, it is an error to build hospitals on the face of a steep slope, or in any situation where there is an impediment to a free circulation of the air. Undrained marshy ground should be avoided, nor should houses or clumps of trees be in close proximity to the building. For hospitals situated in the crowded localities of large towns, convalescent homes in the country, or at the sea-side, are now being provided, and with marked advan- tage to the patients. The late discussions on hospitalism, though perhaps somewhat one-sided in giving such prominence to the test of surgical results, have fully established the great hygienic advantages which small cottage hospitals possess over the large palatial buildings that have hitherto found favour with the profession. It is further generally admitted that, when large hospitals are rendered necessary, they should approximate as much as possible to the sanitary conditions which can only be ensured by small detached buildings. The application of this principle has resulted in the con- struction of hospitals on the pavilion system a system which accommodates itself to almost any site and to any number of patients. SECTION I. PAVILION HOSPITALS. In this description of hospital, each pavilion may be regarded as a separate hospital, and the impurities of every single ward are cut off from the other wards. The pavilions are united by a corridor for administrative pur- poses and for convenience, but are so arranged that a free circulation of air can always take place between them. In its simplest form a pavilion would consist of a single ward, with the necessary additions for administration. HOSPITALS. 261 More frequently, however, it consists of two wards, one above the other, and, in some instances, of three wards, as in the Marine Hospital at Woolwich. Three-storied pavilions are objectionable, because their height necessi- tates a lofty corridor to unite them, and induces stagnation of the air. With two-storied pavilions, on the other hand, the corridor need only be half the height of the pavilions. SCO Fig. 7. General Plan of Herbert Hospital, Woolwich. (From "Construction of Hospitals," by DOUGLAS GALTON.) In large hospitals, such as the Herbert Hospital, the pavilions may be united in twos, end to end, with the corridor running between them, the staircase being, as it Fig. 8. Sketch of the end of the southern Pavilions of Herbert Hospital, showing the elevation of the Corridor. (After GALTOX.) were, strung on to the corridor. The distance between the pavilions should be at least twice their height. 262 HOSPITALS. The basis or unit of hospital construction is the ward. The conditions which determine the size and form of a ward are the following : 1. The number of patients which it should contain. 2. The floor and cubic space allowed to each patient. 3. The arrangements for warming, light, ventilation, and nursing. 1. The number of patients in a ward will depend on the size of the hospital, and, occasionally, on the nature of the cases. A cottage hospital, for example, will neces- sarily consist of small wards, and even in large hospitals small wards are required for isolating very severe or special cases. With these exceptions, however, the number of patients in a ward must depend mainly upon the number which can be efficiently nursed at the smallest cost per head. Miss Nightingale, in the Eeport on Metropolitan Workhouses, fixes this number at 32. She says, " A head nurse can efficiently supervise, a night nurse can carefully watch, 3 2 beds in one ward ; whereas, with 3 2 beds in four wards, it is quite impossible." Throughout European hospitals the number varies from 24 to 32. 2. One of the most important questions attaching to hospital construction is the amount of floor and cubic space which should be allowed to each patient, and there is scarcely any question concerning which there has been so much discrepancy of opinion. Thus, Dr. Todd main- tained that 500 cubic feet were sufficient ; Dr. Burrows, 1000; the Army Sanitary Commission, 1200; and the Committee appointed to consider the cubic space of Metro- politan Workhouses, 850. The recommendations of this Committee further limited the cubic space allowance for dormitories to a minimum of 3 feet, and for wards con- taining infirm paupers to a minimum of 500 feet per head. There is no doubt, however, that, in consequence of the conflicting evidence on which the Committee had to base HOSPITALS. 263 its recommendations, the difficulties of efficiently ventilat- ing small spaces without draught were not sufficiently appreciated ; but as reference has already been made with regard to this point, it need not be again discussed. Suffice it to say that General Morin, the greatest French authority on ventilation, to whom the disputed subject was sub- mitted, gave it as his opinion that, even for paupers who are not ill, he considered it " necessary not to descend below 880 cubic feet of space, and besides this the con- dition must be imposed of renewing the air in the pro- portion of 1060 cubic feet per individual per hour." For ordinary hospital cases it is now generally admitted that a cubic space of at least 1200 feet should be allowed per patient, and for cases of infectious disease, or for severe surgical cases, as much as 2000, and it may be doubted if this be sufficient at all times. On the superficial area per bed will depend the dis- tance between the beds, the facilities for nursing, and the conveniences for ward administration. This, like the cubic space, has been variously estimated. Thus, in St. George's Hospital it is only 6 9 square feet ; in St. Bartholomew's it is 79; in the Herbert Hospital, 99 ; in the Netley Hospital, 1 3 ; in Guy's, 138; and in the new St. Thomas's Hospital, 112. For all nursing purposes, Miss Nightin- gale maintains that at least 90 square feet should be allowed per bed, and this amount, according to Captain Gal ton, should be accepted as a minimum. Where medi- cal schools are attached to hospitals, an extra allowance must be allotted for the requirements of clinical teaching. The space must also be greatly increased in fever or lying- in wards. The height of an average-sized ward should be 13 or 14 feet. 3. For providing sufficient light and for maintaining purity of the air, much depends on the width of the ward. Experience has shown that this should not be less than 264 HOSPITALS. 24 feet, and not more than 30 or 35. In the new. Leeds Hospital it is 27 feet 6 inches ; in the new St. Thomas's 28 feet; and in the Herbert Hospital 26. The ventilation of each ward should be entirely in- dependent of the others, and to effect this, cross-ventilation by means of open windows, aided by Sheringham valves, extraction flues, and ventilating fire-places, is deemed to be the most efficient. In the summer months, when fires are not required, the windows should always be kept more or less open, except during rough, blustering weather. When a window is allowed for each bed, which is sometimes the case, the wall-space between the windows should be six or eight inches wider than the bed. In the pavilion system, however, an allowance of one window for every two beds is generally considered sufficient, the beds being arranged in pairs between the windows, and sepa- rated from each other by a distance of at least three feet. The windows should reach from within two feet or two feet six inches from the floor to within one foot from the ceiling. The space between the end wall and the first window on either side of the ward should be four feet six inches, and the space between the adjacent windows nine feet, the windows themselves being four feet six inches wide. An end window to a long ward adds greatly to its cheerfulness, and aids materially in the ventilation of the ward. The ordinary sash window, made to open at top and bottom, is perhaps preferable to any other kind. To economise heat, plate-glass should be used instead of ordinary glass. In addition to means of ventilation provided by win- dows, there should be a fresh -air inlet, furnished with a Sheringham valve, placed near the ceiling and between each window, or an upright ventilating tube of the kind recommended by Mr. Tobin. When the fire-places are situated in the external walls, two or three fresh-air inlets HOSPITALS. 265 may be provided at equal distances along the centre of the floor, and communicating by means of transverse flues beneath the flooring with the external air. Such inlets are so far removed from the beds that the currents enter- ing through them are not felt by the patients when in bed, and they could be closed if deemed necessary during the day-time. The gratings covering them should be capable of easy removal, so that the flues may be cleaned out regularly. The extraction flues should be situated, if possible, on the same side of the ward as the fire-places, and should be carried above the roof and louvred. When not con- tiguous with a chimney, they should be provided with gas-jets to aid their extractive power. If the fire-places are situated in the centre of the ward, the extraction-flues should be placed in the opposite corners. The inlets to extraction-flues ought to be near the ceiling, but not in close proximity to the fresh-air inlets. The fire-places best suited for infirmary wards are the ventilating stoves already described in the Chapter on Ventilation. But in addition to these, or in place of them, the fresh air might also be heated by hot-water pipes, coiled in boxes below each bed, as recommended by Dr. Parkes, or the pipes might pass along behind the skirting, the skirting being perforated or supplied with k^atings opposite each bed for the admission of the heated air. Every gas-jet in a ward should be furnished with a bottomless lantern, communicating with an extraction-tube, to carry off the products of combustion, or Eickett's ven- tilating globe lights should be used. (For particulars with regard to ventilation, see Chapter on that subject.) The furniture in a ward ought always to be reduced to a minimum, and should never be cumbrous or bulky. Iron bedsteads are to be preferred to wooden ones, and 266 HOSPITALS. thin horse-hair mattresses, placed on springs, or on woven wire mattresses, to thick flock or woollen mattresses. All bedsteads should be ranged at a short distance from the walls. Coverlets and blankets should be white or light- coloured, to show dirt, and ought to be frequently aired. The other points of sanitary importance connected with a ward are its offices, and the materials employed in construction. Ward-offices are required for facilitating nursing, and for the direct use of the sick. Thus every ward should have attached to it, at the end nearest the door, a scullery and a nurse's room, and, at the farther end a water-closet and ablution -room. The nurse's room should be light and airy, and large enough to be used as a bedroom. It should also be provided with a window, looking into the ward, for purposes of inspection. The scullery should be situated opposite the nurse's room, and ought to be fitted with a small range for warming drinks, preparing fomentations, etc.; a sink with hot and cold water laid on ; and shelves and racks for dishes. It should be large enough for the assistant nurses to take their meals in. The water-closet and ablution-room should be situated, w Fig. 9. (After GALTON.) one at either farther corner of the ward, and both should be completely cut off by means of swing-doors and a lobby supplied with cross-ventilation from the ward. The water-closet apartment ought to contain one closet for HOSPITALS. 267 every 10 beds, or 3 closets for 32, and should also be supplied with a sink and a urinal. Instead of a handle and plug for turning on the water for flushing, it is pre- ferable to have a self-acting water-supply connected with the door, because some patients are careless, and others are too feeble to raise the handle. The ablution-room should contain a plunge-bath with hot and cold water laid on, a shower-bath overhanging the broad end of the plunge-bath, and a lavatory table fitted with basins, and also supplied with hot and cold water. There should likewise be room enough to contain a port- able bath on wheels, a hip-bath, and a foot-bath for the use of patients more or less bed-ridden. The pipes lead- ing from the sink and lavatory table should not be boxed in, because the spaces thus enclosed become receptacles for dirt. The supply of water should be ample, and the drain- age and sewerage perfect. All closet pipes should be ventilated and placed against outside walls, and all other pipes disconnected from the drains. The various fittings should be of a light colour, to show dirt, and thus ensure thorough cleanliness. The walls of closets and ablution- rooms should be lined with Parian cement, glazed tiles, or enamelled slate. With regard to- the materials of ward construction, it is now strongly recommended that floors should be made of hard wood, such as oak laid on concrete and well jointed ; that the walls should be lined with Parian cement, or well plastered, periodically cleaned, and white- washed or painted ; and that the ceilings should be plas- tered and whitewashed, or painted a light colour. Floors of upper wards ought to be non-conductive of sound. A ward thus constructed and arranged is in itself a small hospital, and the aggregation of ward units will depend on the number of patients to be accommodated. 268 HOSPITALS. In an average-sized hospital the administrative build- ings occupy considerable space, and may be variously dis- tributed. All of them, however, must be made entirely subservient to the requirements of the sick, and should not interfere with the ventilation of the wards. Usually the administrative buildings are as follows : Kitchen, provision-stores, and stores for bedding and linen. These should be central. Apartments for house-surgeon, matron, and servants ; consulting-room, waiting-room, surgery, drug-store, and operating-room ; all of them more or less central. Laundry, mortuary, post-mortem room, disinfecting- room. These should all be detached from the building. The night-nurses should have well -ventilated bed- rooms at a distance from the wards, with all the necessary appliances for ablution, etc. The staircases for patients should be broad and easy, and should be cut off from the connecting corridors by swing-doors. The corridors themselves should be as low as possible, well lighted, warmed, and ventilated. According to Captain Galton, the administrative Fig. 10. General Plan of Swansea New Hospital. A, Administration ; B, Men's Wards ; C, Women's Wards and Out-patients ; D, Operating Room and Eye Ward. (After GALTON.) buildings take up about half the cubic space of the whole hospital. As very good examples of the pavilion form of HOSPITALS. 269 hospital on the small scale, he instances the Eoyal Hants County Hospital at Winchester, the Buckinghamshire County Hospital at Aylesbury, and the New Hospital at Swansea. With regard to the cost of pavilion hospitals, Captain Galton is of opinion that, with care and attention to economy in the design, a hospital for in-patients only, and built on a favourable site, should not cost more than from 90 to 120 per bed. The Leeds Hospital, which accommodates 350 patients, cost 197 per bed; the Eoyal Hants Hospital, with 108 beds, and including accommodation for out-patients, cost 229 ; and the Swansea Hospital, also including an outside-patient de- partment, cost 142 per bed. Day-wards, exercising grounds, and flower or winter gardens, are great additions to the sanitary advantages supplied by a well-constructed hospital. In summer, all the patients who are able to move about, and, indeed, most of those who are bed-ridden, should be allowed to remain during some part of every warm day in the open air. The flat roofs of the corridors, protected by awnings, could be utilised for the bed-ridden patients of the upper wards, while the corridors themselves might be appropri- ated by the same class of patients belonging to the lower wards. With very little extra expense the corridors could be converted into winter gardens. during the colder months of the year, and might be occupied by patients in the day-time without interfering with any of the ad- ministrative arrangements. SECTION II. COTTAGE HOSPITALS. The cottage hospital system, originated by Mr. Napper of Cranleigh, is based on the principles of providing 270 HOSPITALS. hospital accommodation for the sick poor of rural districts, with as much of the surroundings of home as possible ; of permitting equality of privilege to subscribers in recom- mending patients, the patients themselves paying a certain sum weekly, according to their means; and of allowing any medical man practising in the district the use of the hospital for deserving cases under his care. The model cottage hospital should not have more than twenty beds, and must be under the management of one medical man as director, appointed either permanently or by rotation, the other medical men in the district holding office as honorary medical officers. The annual cost of the estab- lishment is defrayed chiefly by voluntary contributions and partly by the weekly payments of the patients. These weekly payments, as already stated, are regulated by the means of the patient, and vary from 2s. 6d. when the Union has to help, to 5s. or 8s. when the patient has been earning fair wages, or belongs to a club. All fees allowed by the Union for accidents or operations are paid to the Union medical officer, in the same way as if he had attended the patient at his own home. Every subscriber, no matter what the amount of his subscription, should have equal privileges in recommending cases, and will generally be able to state what amount the patient whom he recommends can afford to contribute weekly. Cases of accident and emergency are admitted without order, but otherwise a recommendation from a subscriber must be procured, and this should in all instances be accompanied by a certificate from one of the medical staff, to the effect that the case is one deserving and fit for admission. Only those are admitted who cannot be efficiently treated at their own homes, while cases of infectious or incurable disease are excluded. In some few hospitals pay patients are admitted where there is sufficient accommodation, and it is rightly urged by Mr. Burdett in his excellent work "HOSPITALS. 2*71 on Cottage Hospitals that this system should be extended to all hospitals. Experience has proved that in rural districts a cottage hospital of six beds will suffice for a population of 6000. The initial outlay will of course depend on whether a cottage which has already been built can be procured, and, if so, what alterations will be necessary to convert it into a hospital. If the hospital has to be built, the amount required may be estimated at 600, or about 100 per bed. In converting a cottage which has already been occupied into a hospital, the walls should be thoroughly, cleaned, scraped, and afterwards re-plastered and washed with caustic lime. Attention must also be paid to the sanitary surroundings of the building. The cost of furnishing a cottage hospital for six beds will amount to about 100, and the necessary surgical instruments to about 50. The maintenance per patient weekly would cost from 10s. to 15s., so that the hospital, when once started and properly furnished, will require for its support an annual income of at least 150, about 25 or 30 of which will be subscribed by patients. Although the architectural arrangements may admit of many variations, the plan best suited for a cottage hospital of six beds should provide for a nurse's room, a three-bedded male ward, a two-bedded female ward, a single-bedded ward, which can be used as an operation room, a kitchen, which may also be used as a day -ward, a scullery, and a small mortuary. All the rooms should, if possible, be on the ground-floor, so that good roof venti- lation and ample cubic space may be secured. Part of the roof should overhang, so as to form a sort of verandah for the use of patients. It need scarcely be added that a tasteful arrangement of flowers and shrubs in the space immediately surrounding the hospital will add greatly to its cheerfulness. 272 HOSPITALS. As regards nursing, cooking, and management, much will depend on the size of the hospital, but efforts should always be made to secure the services of a trained nurse. If a cesspool is used as the receptacle of excreta, it should be at a safe distance from the building, and con- structed as described in the Chapter on Dwellings ; but where no water is laid on, the pail or dry-earth system is to be preferred. (See Handy Book of Cottage Hospitals, by Dr. Swete, and the much more exhaustive work, Cottage Hospitals, by Mr. Burdett.) SECTION III. HOSPITALS FOR CASES OF INFECTIOUS DISEASE. By the 131st clause of the Public Health Act, 1875, power is given to the sanitary authorities of any town or district to provide, for the use of the inhabitants, " hospitals or temporary places for the reception of the sick;" and when such provision has been made, any Justice may order the removal to the hospital of any person suffering from a dangerous infectious disease who is without proper lodging, or lodged in a room containing more than one family, or is on board ship. Judging from my own experience, however, and that of other health officers, it is very seldom that a magistrate's order is re- quired for the removal of a patient, inasmuch as patients and their friends are, as a rule, only too glad to avail themselves of the advantages of a hospital of the kind, when proper isolation and adequate nursing cannot be procured at their own homes. In a Memorandum of the Privy Council, printed in the Appendix to the First Eeport of the Local Govern- ment Board, it is recommended, as a condition of the first importance, that the accommodation for isolating HOSPITALS. 273 cases of infectious disease shall be ready beforehand ; and further, that it shall be sufficient for the treatment of different infectious diseases separately. The amount of accommodation required will of course vary for different places. As regards villages, for example, it is recommended that "each village ought to have the means of accommodating instantly, or at a few hours' notice, say four cases of infectious disease, in at least two separate rooms, without requiring their removal to a distance. A decent four-room or six-room cottage, at the disposal of the authority, would answer the purpose. Or permanent arrangement might be made beforehand with trustworthy cottage - holders not having children, to receive and nurse, in case of need, patients requiring such accommodation. Two small adjacent villages (if under the same Sanitary Authority) might often be re- garded as one." If further accommodation be at any time required, neighbouring cottages should be hired, or tents or huts may be erected on adjacent ground. Practically, however, it is found that Sanitary Authorities are generally so averse to providing any accommodation of the kind, unless under the stern pressure of an epidemic, that in rural districts, especi- ally, the health officer may consider himself fortunate if he succeeds in obtaining a place sufficiently central to meet the requirements of a whole union, or at least the most populous parts of it. With a good ambulance, patients, if fit to be moved at all, can, I believe, be moved a distance of about six or eight miles without risk. In reference to this point, Dr. Thome, in his exhaustive report on Infectious Hospitals, says : " It is not that removal for a distance of some five, and even in isolated instances, eight and ten miles in a well-con- structed ambulance, and over ordinarily good roads, has T 274 HOSPITALS. appeared to do harm to the particular patient, provided the removal has heen effected at an early stage of the disease. By far the greatest difficulty in the matter of distance has been found, as a rule, to lie with the relatives and friends of the patients, who assent much more readily to removal to hospital if it be within such distance as to enable them, without much trouble and without material interference with their business and other avocations, to make frequent inquiry as to the patient's welfare. In rural districts, the question of distance is usually less thought of than in urban districts, especially when the hospital to which removal is effected is in or near some centre to which the population often travel in connection with their daily or occasional pursuits." Then, too, it was found in the course of Dr. Thome's inquiry, that strong objection was often raised to the removal of patients from one district to another, as from rural districts in the neighbourhood of large towns to hospitals situated in those towns, even when arrangements had been made between the Sanitary Authorities for the reception of patients from adjoining districts. (See Tenth, Annual Report of the Local Government Board, 1882.) The question here arises, and it is a somewhat difficult one to answer, What should be the ratio of beds to the population for whose wants the hospital is to be provided ? Dr. Buchanan, in a very able address delivered in 1876 to the Medical Society of London, lays down the ratio of one bed to every 1000 inhabit- ants, and no doubt, taking this as an average estimate, it may be considered as fairly accurate. But much will depend upon the special circumstances of the district and population. For example, a poor crowded district will require a larger amount of accommodation than a district not crowded, and whose inhabitants are on the whole well off. In the latter case, the ratio of one bed to HOSPITALS. 2*75 every 2000 inhabitants, with means for temporary ex- tension, if it should be required, might be considered sufficient. It heed hardly be said that the greatest difficulty 'is frequently experiened in obtaining a site. Vested in- terests at once take alarm because the popular prejudice against living in the vicinity of such hospitals is so great that property will, for the time being, depreciate in value. The site, therefore, which may be ultimately fixed upon may not be free from objection, but it should always be such that no sanitary objection can be raised against it. If the soil is stiff and clayey, special care ought to be taken, by means of drainage, a free use of concrete or asphalt, and abundant ventilation, to secure perfect dryness of the building. The building itself should be sufficiently central as regards the distribution of the population of the district, sufficiently accessible from all parts of the district, and, if possible, well isolated. In rural or suburban districts, there ought to be no difficulty in obtaining an abundant supply of good water, nor any difficulty in getting rid of the excremental matters and slops. The question of cost of site will of course vary im- mensely according to the circumstances of the district, while the amount of space required will also vary very much. But, speaking roughly, no site to afford sufficient isolation should be less than one acre in extent, and a hospital, say of thirty beds, would require about two acres. Then, too, the site should be surrounded by a suitable fence to cut off all communication except through the lodge entrance, and such fence Dr. Thorne recom- mends should be a wall about 6 feet 6 inches high. The following table from Dr. Thome's report gives im- portant particulars with regard to the best arranged permanent hospitals which he visited : 276 HOSPITALS. I IJ 1 i|g II. fcl 31 |1. c3 +^ o ^3 * ' -* rt ^Q QJ c8 ^ ^ C3 *t2 t-t ?; 5 !, 1 g 5-3 8 <& ?.S 1"! O & O 4^ 'S SI a 5 Efl P Ita Is il Berkhampstead, rural 11,000 8 07 144 2000 2,162 270 Cheltenham, urban . 44,000 32 07 Varies ; Varies ; 11,121 347 mean is 144 mean is 2300 Darlington, urban . 35,000 44 1-3 144 to 175 2000 10,123 225 Folkstone, urban 18,700 14 07 140 1 2000 2,800 200 Lewes, combined districts 11,200 12 1-1 144 2000 1,975 164 Middlesborough, i urban . 56,000 32 0-6 122 to 180 1620 to 2100 6,829 213 Sheffield, urban 285,000 64 0-2 138 1810 19,785 309 Solihull, rural . 20,000 12 0-6 144 to 156 2000 to 2184 2,892 241 Tonbridge, urban . 10,000 12 1-2 140 2000 1,394 116 Warrington, urban . 42,000 28 07 144 to 175 2058 to 2529 6,555 234 "Weymouth, port ? 26 ? 144 to 169 2014 to 2028 5,135 192 Permanent hospitals should be built of brick or stone, and not of wood or corrugated iron, because, apart from other reasons, it was found in the course of Dr. Thome's inquiry that it was very difficult to maintain in the latter class of buildings a sufficiently warm temperature in cold weather. They should be built on the pavilion system, and consist of an administrative block; at least four wards, in two separate pairs, in which patients of both sexes, suffering from two different infectious fevers, can be HOSPITALS. 27*7 simultaneously treated ; and certain outbuildings, such as mortuary, laundry, etc. The administrative block is usually built in excess of the requirements of the permanent pavilions, so as to be commodious enough for any future extensions, should they become necessary ; and where it is desirable to economise space, it may be a two-storied building. It should only communicate with the pavilions by means of covered passages with free cross-ventilation ; and should be so situated that persons can enter it without passing close to the pavilions. The pavilions themselves are generally one-storied buildings, but where a site is necessarily limited Dr. Thorne saw no reason to object to two-storied pavilions, provided of course that only patients suffering from one kind of infectious disease are treated in the same pavilion the patients of one sex on one floor, and the patients of the other sex on the other floor. The distance between the several pavilions and between them and the administrative block should be equal to one and a half times their height, and when the buildings are of unequal height, it should at least be equal to the full height of the higher of the adjacent buildings. Dr. Thorne further recommends that in the case of a smallpox pavilion, the separation between it and the other hospital buildings should, if possible, be even still more complete, or it should be, as at Folkestone, an entirely separate institution. At Folkestone, too, arrange- ments have been made for the reception of better class patients into a separate block of small wards, and there is no doubt that such an addition to most infectious hospitals would be a great boon to paying patients, besides affording means for isolating noisy or delirious patients and doubtful cases. The construction and arrangement of the ward pavi- lions are so similar to the details already given with regard 278 HOSPITALS. to general hospitals that only a few additional particulars may be given here. The cubic space per bed, according to the memorandum of the Local Government Board, should be at least 2000 feet, and the minimum floor space per bed 144 square feet. The height of the wards, should be about 14 feet, and no additional height should be taken into account in reckoning the cubic space. The floors should be closely jointed, the walls either covered with Parian cement, or made smooth and limewashed and coloured, and flat ceilings without cornices should be pre- ferred to pitched roofs. The windows should be double- sashed, and be evenly distributed in the opposite walls, so as to ensure efficient cross-ventilation. The best arrange- ment is found to be that which provides for one window between every two adjacent beds, and one near the angles of the ward beyond each end bed. They should reach from about 3 feet above the floor level to within 6 inches of the ceiling or wall-plate, and the amount of window space should be in the proportion of 1 square foot to about 70 cubic feet of ward space r- too much window space having been found to interfere with the equable warmth of the contained air. In addition to the window ventilation, Dr. Thome re- commends that there should be ventilating openings under each bed, and just above the floor level, and each capable of being closed by means of a small sliding-door on one or other side of the ward, according as the direction of the prevailing wind may determine. The ward ventilation should be supplemented by vertical enclosed shafts passing through the roofs, or special flues opening near the ceiling, and carried alongside the chimney flues. With regard to warming, it was found that open fire- places are best adapted for ward purposes, and preferably those of the ventilating kind. When wards exceed 30 feet in length, ventilating stoves, having an open fire-place HOSPITALS. 279 both back and front, should be provided in the centre of the ward, or instead of these close ventilating stoves may be substituted. In connection with each ward pavilion there should be an entrance lobby, a nurse's room fitted with fixed windows to command a view of either ward, a room in which to store food, and a linen store. In small hospitals the nurse's room is often fitted as a ward kitchen, and provided with a scullery sink. In two-storied pavilions similar apartments should occupy the end of the ward which adjoins the entrance lobby and staircase. At the opposite end of the ward, closets, sinks, and bathing accom- modation should be provided in a building projecting from the main payilion, as already described in Section I., and separated by a lobby provided with efficient means of cross- ventilation. When no separate bath-room is provided, a movable bath on wheels is found to answer the require- ments of small hospitals. It need hardly be said that the drainage should be perfect in all its details, and the water-supply abundant and wholesome. Where there are no public sewers the closets should be dry closets, provided with movable recep- tacles, which can be removed through a small doorway in the outside wall, and the best way of treating the slops is by sub-irrigation from a Field's syphon flush-tank. (See Chapter XL, Section VII.) The furniture of the wards should be simple and neat ; and, for obvious reasons, all bed-curtains, carpeting, or matting should be prohibited. The best kind of bedsteads are iron bedsteads, provided with wire -woven mattresses, and thin horse-hair beds, which can be easily disinfected in a disinfecting chamber. The outbuildings should consist of a porter's lodge, if the hospital is of considerable size, a mortuary, a laundry, an ambulance shed, and a disinfecting chamber, and if 280 HOSPITALS. necessary a post-mortem room all of which should be built at a safe distance from the pavilions. According to Dr. Thome, the most efficient disinfecting chamber is the one devised by Dr. Kansome, of Notting- ham ; and another, which has been highly commended, is the disinfecting chamber devised by Dr. Scott. Temporary extension of the accommodation of any hospital may be provided in the summer and autumn by tents, and in the winter and spring by wooden huts. The tents recommended are, the regulation bell-tent of the War Department, 513 cubic feet space, and the regulation hospital marquee of 3000 cubic feet space. The former should not contain more than one patient, nor the latter more than three. The ground on which they are pitched should be kept dry by means of trenches around and be- tween them ; the floors should be boarded ; the approaches paved or boarded; and the tents themselves should be everywhere distant from each other at least a diameter and a half. All slops and refuse matter should be care- fully removed. In the recent outbreak of smallpox at Wednesbury, large double canvas tents were used with great success, and it was found that they could be effi- ciently warmed with hot-water pipes. With regard to huts, " dryness of site is, as in the case of tents, of the first importance. Each hut should be trenched round. Its floor should be raised a foot or a foot and a half from the earth, so as to permit the free under-passage of air ; but care must be taken to prevent the lodgment of moisture or impurities beneath the floor. A distance not less than three times the height of a hut should intervene between any two huts, and each hut should be so placed as not to interfere with free circula- tion of air round other huts. In huts, as in permanent buildings for the treatment of infectious diseases, not less than 2000 feet cubic space, with 144 square feet of floor, HOSPITALS. 281 should be given to each patient. The ventilation of huts, also, is of equal importance with that of permanent hospital buildings. It is best secured by the combination of side- windows with roof-opening, the latter protected from rain, and running the whole length of the ridge of the roof. The windows, capable of being open top and bottom, should not be fewer than one to each pair of beds, or in large huts one to each bed, nor should be of less size than the sash-window in common use for houses. The venti- lating opening beneath the ridge may have flaps, movable from within the hut by ropes and pulleys, so that the opening to windward can be closed, if necessary, in high winds. Double -walled wood huts may have additional ventilation by the admission of air beneath this outer and inner wall, and its passage into the interior of the hut through openings with movable covers at the top of the inner lining. The roof should be covered with waterproof felt; the edges of the felt fastened down by strips of wood, not by nails. The hut should be warmed by open fire-places, fixed in brick stove stacks placed in the centre of the floor, the flue being carried through the roof." (See Memorandum of Local Government Board.) D Q D 1A1I WAKO GO 48 X 8* OLOOM. A DOIT^ ROOM* Fig. 11. The above is a ground-plan of a hospital hut for 282 HOSPITALS. eight patients of each sex, having the same infectious disease. Fig. 12 is a ground-plan of an extension of hut hos- pitals for ten patients of each sex, having the same infectious disease, where plenty of ground is available. Both these plans are copied from the Memorandum of the Medical Department of the Local Government Board already referred to. Fig. 12. Fig. 12. A, Administrative Buildings (Kitchen, Stores, Offices, Nurses' Bed-rooms, etc.) ; B, Laundry, etc. ; C, Disinfection, Dead-house, etc. ; D, Huts for 10 patients each, with Scullery and Bath-room at end, and Closet and Sink at other end of each ; E, Open Corridors. The dotted lines show direction of further extension. Fig. 13. HOSPITALS. 283 Fig. 13 is the ground-plan of a hospital which was built in the Solihull Union, which forms part of the Mid- Warwickshire sanitary district, in 1876. The general principles of the plan are those laid down in the Local Government Board Memorandum, although the details were modified to suit local circumstances. The central block A contains a kitchen, bed-room, larder, small sur- gery, etc. There is a doorway, E, in each corridor, D, so that the patients in the blocks B and C can be kept completely apart if required. In addition to these blocks there are out-buildings containing a porter's lodge, a disinfecting chamber, a dead-house, a wash-house and laundry, and a shed for an ambulance. The population of the Union is about 21,000, and the site covers two acres of ground, and cost 400. As an illustration of the value of hospital provision for infectious cases, I may quote Dr. Buchanan's remarks concerning the smallpox hospital in Cheltenham, from the address already referred to : " Here fourteen beds are permanently provided for smallpox cases in an admirable little hospital that is devised to suit the wants of well-to-do people, as well as those who may be sent to it by the public authorities. In six months of last year smallpox was brought into Cheltenham no less than six times, from Gloucester, from Birmingham, from Liverpool, and elsewhere. Seven persons ill of the im- ported disease were taken without delay to the Delaney Hospital, and except one individual, who was also re- moved to the hospital, nobody in the town caught the disease from these centres of contagion. There was literally no other smallpox in the town. How much there would have been if, in the absence of the hospital, the seven importations had been allowed to spread their contagion in a widening circle round each, can of course only be a matter of surmise." 284 HOSPITALS. The management of a small infectious hospital would be very much like that already described as suitable for a cottage hospital. A medical officer should be appointed who would have full powers as superintendent, but any patient should have the option of being placed under the care of his own medical attendant should he desire it, provided he pays for the cost of attendance. No obstacles ought to be thrown in the way of admitting patients, and no payment should be insisted on except in special cases or where private wards are provided. A skilled nurse can always be obtained on the shortest notice from any of the excellent nursing institutions advertised in the medical papers. At times when the hospital is not occupied, the building and bedding should be kept clean and well aired. (For Eules of Management, see Appendix.) An indispensable adjunct to a hospital is a well- constructed ambulance. In the Appendix will be found the official instructions with regard to ambulances gener- ally, but a few hints introduced here may likewise prove serviceable. A one-horse omnibus, with door behind and easy springs, can be converted into a very comfortable ambulance by taking out all the lining and polishing or varnishing the wood work. The space beneath the driver's feet should be utilised in extending the internal space, and this should receive the foot-end of the stretcher. The stretcher should be made of wire or wicker work, and the handles should be jointed, so that when the stretcher is placed in the ambulance the handles will not encumber any of the space. Instead of a stretcher, a net hammock slung on hooks will be found to be a very comfortable mode of conveying children and young persons ; indeed, for that matter, there ought to be no difficulty in sling- ing the stretcher itself by means of strong indiarubber bands attached to properly fixed hooks or bars. Such HOSPITALS. 285 an arrangement would remove much of the discomfort arising from jolting, which good springs do not always prevent, and it would cost little, either in ingenuity or as regards expense, to carry it out. In addition to the stretcher or hammock, there should be a hinged seat near the door for the attendant, and one or two hot water cans to secure sufficient warmth in cold weather and during a long drive. After being used, the ambu- lance should be thoroughly disinfected by being washed with a strong solution of sanitas, or any other disin- fectant which does not leave a disagreeable smell after- wards. The comfort of the patient would be greatly increased if, in addition to good springs, the ambulance were provided with noiseless wheels having indiarubber tires. Particulars with regard to a disinfecting chamber will be given in Chap. XIV. When an infectious hospital is required at very short notice, it may be run up- of wood or corrugated iron ; or, to meet sudden emergencies, it has been sug- gested that " flying hospitals," consisting of two or more large vans, which could be moved by road or rail, would be found to be of immense service, and they could no doubt be so arranged as to be made quite as comfortable as hut hospitals. Double canvas tents pitched on wooden floors have also been utilised to meet an emergency at Grantham, Newark, Wednesbury, and other localities, and with a large amount of success. At seaport towns it is proposed to use hospital-ships of the " Dreadnought " type, but any hull of an old vessel capable of floating, and large enough, would suffice. Wooden huts erected on the upper deck would supply the ward accommodation, while the body of the vessel could be utilised for the administrative department. Such hospital-ships would prove of immense value in the event of cholera again visiting this country. 286 HOSPITALS. SECTION IV. MORTUARIES. In connection with this subject of hospitals, some hints may be given with regard to public mortuaries. By Section 141 of the Public Health Act, 18*75, it is enacted that any Sanitary Authority, whether urban or rural " may, and if required by the Local Government Board, shall, provide and fit up a proper place for the reception of dead bodies before interment, and may make by-laws with respect to the management and charges for the use of the same ; they may also provide for the decent and economical interment, at charges to be fixed by such by-laws, of any dead bodies which may be received into a mortuary." Further, it is enacted by Section 142, that " when the body of one who has died of any infectious disease is detained in a room in which persons live or sleep, or any dead body which is in such a state as to endanger the health of the inmates of the same house or room, any Justice may, on a certificate signed by a legally qualified medical practitioner, order the body to be re- moved at the cost of the Local Authority to any mortu- ary provided by such Authority, and direct the same to be buried within a time to be limited by such order." Such are the provisions of the Public Health Act, but except it be in large towns and even in them there is still a great lack of adequate mortuary accom- modation little or no effort has been made by Sanitary Authorities in this direction, and hence Section 142 becomes practically inoperative. Mr. Burdett, in his excellent work on Cottage Hospitals, already referred to, suggests that not only should mortuaries be provided at all hospitals, but that Sanitary Authorities should contract with hospital managers to receive bodies from overcrowded homes on payment of certain fees or of a fixed annual HOSPITALS. 287 subscription. The estimated cost of a small brick build- ing, with two compartments, including mortuary, two waiting-rooms, and a disinfecting chamber, is laid down at between 200 and 300. For large towns the mortuary should be sufficiently capacious to hold ten or twelve bodies placed in shells or coffins resting upon trestles or movable iron brackets fixed around the sides of the building. The post-mortem room should be ad- joining, but quite distinct from the mortuary. It should be well lighted, well ventilated, and be provided with special appliances for post-mortem examinations. There should also be a room or rooms for the accommodation of the coroner and jury in inquest cases, as at Islington, Clerkenwell, and the City of London. As regards the regulation and management of mortuaries, a large amount of valuable information is given by Mr. Burdett in his work on Cottage Hospitals. 288 REMOVAL OF SEWAGE. CHAPTEE XL REMOVAL OF SEWAGE. THE term sewage may be conveniently used as indicating the excrementitious matter thrown off by the bowels and kidneys, and, indirectly, the refuse, whether solid or liquid, which is constantly accumulating in inhabited places, and requires to be constantly removed if cleanli- ness and health are to be maintained. A consideration of this subject will therefore have reference not only to the different methods of excretal removal, but also to scavenging. Although in thinly-populated districts it might be inferred that the disposal of the excreta and house- refuse ought to be attended with very little risk, it is found practically that, owing sometimes to nearness to the house, or at other times to being close to the well, the midden or cesspool frequently becomes the cause of severe illness, and, if the contents are allowed to accumu- late, is always a source of real danger. Even when a house stands widely apart from every other, the occupier cannot safely neglect the sanitary obligation which rests upon him of disposing of his house refuse, whether solid or liquid, so that there shall be no foul smells to taint the air, nor foul leakage from drains or cesspools to pol- lute his drinking water or render unhealthy the walls and foundations of his dwelling. And in proportion as houses are gathered together in towns or large villages, it REMOVAL OF SEWAGE. 289 need hardly be said that this sanitary obligation becomes more and more important. Yet nothing is more clearly established in the numerous reports of the Medical In- spectors of the Local Government Board and in published reports of health officers from all parts of the country, than the gross and utter neglect which still prevails with regard to that continuous and systematic removal of all filth which can alone ensure even an approach to clean- liness. In the words of Mr. Simon " There are houses, there are groups of houses, there are whole villages, there are considerable sections of towns, there are even entire and not small towns, where general slovenliness in everything which relates to the removal of refuse matter, slovenli- ness, which in very many cases amounts to utter bestiality of neglect, is the focal habit ; where within, or just outside each house, or in spaces common to many houses, lies for an indefinite time, undergoing foetid decomposition, more or less of the putrefiable refuse which house-life, and some sorts of trade-life, produce ; excrement of man and brute, and garbage of all sorts, and ponded slop-waters, some- times lying bare on the common surface ; sometimes un- intentionally stored out of sight and recollection in drains or sewers which cannot carry them away ; sometimes held in receptacles specially provided to favour accumulation, as privy-pits, and other cesspools for excrement and slop- water, and so-called dust-bins receiving kitchen refuse and other filth. And with this state of things, be it on large or on small scale, two chief sorts of danger to life arise ; one, that volatile effluvia from the refuse pollute the surrounding air and everything which it contains ; the other, that the liquid parts of the refuse pass by soakage or leakage into the surrounding soil, to mingle there of course in whatever water the soil yields, and in certain cases thus to occasion the deadliest pollution of u 290 REMOVAL OF SEWAGE. " wells and springs. To a really immense extent - - to an extent, indeed, which persons unpractised in sanitary inspection could scarcely find themselves able to imagine, dangers of these two sorts are prevailing throughout the length and breadth of this country, not only in their slighter degrees, but in degrees which are gross and scandalous, and very often, I repeat, truly bestial. And I state all this in unequivocal language, because I feel that, if the new sanitary organisation of the country is to fulfil its purpose, the administrators, local and central, must begin by fully recognising the real state of the case, and with consciousness that in many instances they will have to introduce for the first time, as into savage life, the rudiments of sanitary civilisation." " A second point which, equally with the above, needs f to be recognised by all who are responsible for the pre- vention of filth -diseases, is that filth does not only infect where it stands, but can transmit its infective power afar by certain appropriate channels of conveyance ; that, for instance, houses which have unguarded drainage com- munication with cesspools or sewers may receive through such communication the same filth-infections as if excre- ment stood rotting within their walls ; and that public or private water-reservoirs or water-conduits, giving acci- dental admission to filth, will carry the infection of the filth whithersoever their outflow reaches. Thus it has again and again happened that an individual house, with every apparent cleanliness and luxury, has received the contagium of enteric fever through some one unguarded _drain inlet ; or that numbers of such houses have simul- taneously received the infection, as an epidemic, in places where the drain inlets in general have been subject to undue air pressure from within the sewer. And thus, equally, on the other hand, it has again and again hap- pened that households, while themselves without sanitary REMOVAL OF SEWAGE. 291 reproach, have received the contagium of enteric fever through some nastiness affecting (perhaps at a consider- able distance) the common water-supply of the district in which they are." (See Mr. Simon's Reports' New Series, No. II.) In describing briefly the various methods of sewage- disposal, it will be convenient to discuss the subject under the following sections : 1. The water system. 2. The privy or midden system. 3. The pail system. 4. The dry system. 5. Lieurnur's, and other continental systems. 6. Systems best suited for rural districts. 7. Disposal of slops. 8. Public scavenging. With regard to systems other than the water-carriage system, most of the information here collated has been obtained from the valuable joint-report of Dr. Buchanan and Mr. Netten Eadcliffe (see Mr. Simon's twelfth Report to the Privy Council), and from the still more elaborate report of Mr. Netten Eadcliffe, contained in No. II. of the New Series already referred to, as well as from the report on sewage-disposal issued by the Local Government Board in 1876, and other works. SECTION I. THE WATER SYSTEM. Where there is no unusual difficulty in dealing with the sewage at the outfall, there can be no doubt that the water-carriage system of sewage removal is the one best suited for large towns. In the great majority of towns, however, this difficulty has become so very serious, or the drainage in parts is so defective, that the water system 292 REMOVAL OF SEWAGE. has been supplemented by other plans, varying according to local requirements, but all of them intended to deal more particularly with fsecal matters. Apart from con- siderations of cleanliness and convenience, this system possesses the additional advantage of employing the same channels for the removal of sewage which are required for the removal of waste water, and not only so, but the waste water can in this way be utilised as a very efficient vehicle for the conveyance of the excreta. In most cases the subsoil water, surface water, and the water used for domestic purposes, are all eventually discharged by the same channels, so that the drainage and sewerage of a town usually form part of the same system. 1. Drains and Sewers. In any system of drainage intended to carry off surface water and drain the subsoil, it is necessary that the drainage channels should have sufficient area and declivity to maintain the discharge of the water which they receive at all times, and at its fullest flow. This quantity will of course depend chiefly on the rainfall of the locality to be drained, and upon the amount entering the drains from other sources. Thus, in country districts, the water to be carried off may be partly derived from porous strata, which have their gathering ground beyond the boundary ridges of the drainage-area ; and in towns, the water-supply artificially brought in is added to the amount derived from the drainage of the in- habited district. Moreover, as the soil acts as a kind of reservoir, the water does not enter the drains in the open country as rapidly as it falls, indeed a considerable portion of it is evaporated or absorbed by vegetation ; but in towns it runs off the roofs and paved or macadamised surfaces almost as fast as it is delivered. .. Guided by these considerations, engineers have esti- mated that the capacity and declivity of the water- channels for country districts should be sufficient to REMOVAL OF SEWAGE. 293 carry off the greatest available rainfall occurring during twenty-four hours in that space of time, whereas m towns they should be capable of discharging the greatest ^hourly rainfall on the area, and the greatest hourly supply from other sources. The depth of the greatest hourly rainfall is estimated by different authorities at from half an inch to an inch. In small towns, where the storm- water, or greatest hourly rainfall, may be passed over the surface without causing injury, the main sewers need not be constructed of a capacity to discharge it, a plan which has been carried out at Penzance and Carlisle. In other towns, again as at Dover, Ely, Eugby, etc. most of the storm- water is carried off by the old drain -sewers, and the sewage by separate pipe- sewers ; or pipe-sewers are used exclusively for the sewage, and separate drains are con- structed for the subsoil and storm-waters. This is called the separate system, and it is now adopted in all new plans of drainage which provide for the treatment of the sewage. The advantages of the pipe- sewer system are, that If the pipes, if strong and well jointed, prevent percolation ; that they can be quickly laid, and require much less excavation than brick sewers ; that they can be made of various curves to suit different positions ; and that, with a proper declivity, they are not liable to get fouled. Another great advantage depends on the fact that the sewage can be treated without excessive dilution, and when a pumping -station is required at the outfall the original cost and working expenses are much lessened. On the other hand, the pipe system does not fully ensure the important hygienic condition of drying the subsoil if separate drains are not laid down, or unless subsoil pipes are conjoined with sewer pipes, as in the system devised by Messrs. Brooke and Son of Huddersfield Brick sewers, 294 REMOVAL OF SEWAGE. however, as they are usually constructed, do act efficiently as subsoil drains, but at the same time it must not be forgotten that all such sewers are more or less leaky, and are therefore a constant source of danger to any wells or water-mains which may be near them. / / (1.) Construction of Drain-Sewers. The main drains or sewers of a town are underground arched conduits, built of brick in cement, and should be perfectly water- tight. They are generally laid on a bed of concrete, to prevent sinking of any part of the track, and consequent fracture. The jsross^section preferred for them is an egg- shaped oval, with the small end downwards, and with a width of at least 2 feet, to allow "men to enter them for the purpose of cleansing and repair. They should be laid out in straight lines and true gradients from point to point, so that the current shall have a velocity of not less //than I foot, and not more than 4-| feet, per second. At each principal change of line or gradient, arrangements should be made for inspection, flushing, and ventilation ; and at all junctions or curves the declivity should be in- creased, to compensate for friction. No sewers or drains should join at right angles, or directly opposite the entrance of others. Tributary sewers should deliver in the direc- tion of the main flow, and should also have a fall into the main at least equal to the difference between their diameters. Surface - drains or gutters communicate with the under-ground drains by gulley-holes, which are covered with gratings, and generally fitted with syphon-traps to prevent the escape of foul air. Branch drains, leading from the houses and from the adjoining ground, are usually made of earthenware pipes, bedded on concrete, and well jointed in hydraulic mortar or cement. They should never be less than 4 inches in diameter, and should have a declivity sufficient to ensure a velocity of REMOVAL OF SEWAGE. 295 flow of at least 4^- feet per second, to prevent the forma- tion of deposits. All junctions with other drains or sewers should be curved or acute-angled, and, whenever practicable, they should be made in a vertical or trans- versely inclined, instead of a nearly horizontal, plane. Pipes of small size should always be joined on to pipes of larger size, as 4-inch pipes into 6, 6 into 9, and 9 into 12. No drain should ever commence in the basement of a house, otherwise the up-draught produced by the increased inside temperature will occasionally draw the air through any trap. House-drains should never be less than, or seldom exceed, 4 inches in diameter, and, as previously shown, should be completely disconnected from the public sewers. Cellars should be drained by making the drain so as to discharge upon a trapped grating communicating with the drain outside the wall of the house, or, if this cannot be readily effected, the drain should be trapped, and well ventilated either by a special pipe or an open grating. Where houses have to be drained from back to front through the basement, the drain-pipes should be carefully jointed, bedded in concrete, and ventilated back and front outside the walls of the house. Sink-pipes, and pipes from cisterns, lavatories, or baths, should never com- municate directly with the drains, but should always be carried outside the walls of the house, and be made to discharge on to open trapped gratings communicating with the drains. All soil-pipes should be sufficiently venti- lated, and no other pipes, such as overflow-pipes from cisterns, should open into them. (See Chapter on Dwell- ings.) (2.) Ventilation of Sewers. In order to prevent con- centratiou or stagnation of the gases which are largely given off by sewage, it becomes a matter of the utmost importance to provide numerous Openings communicating 296 REMOVAL OF SEWAGE. with the sewers, to ensure free ventilation. Main sewers, with steep gradients, should have a manhole, a tumbling bay, and double ventilating arrangement, at intervals of not less than 300 yards. The tumbling bay or fall is provided to allow of a flap-valve being applied to the discharging end of the sewer, and thus compel the gases Fig. 14. Manhole, Tumbling Bay, and Double Ventilating Arrangement. (After RAWLINSON.) to ascend through the ventilating shaft. One or more charcoal baskets may be placed in the man-hole. to deodor- ise the sewer-air as it escapes, and before it enters the ventilating chamber, but charcoal should never be used when it can be avoided, because it impedes free ventila- REMOVAL OF SEWAGE. 297 tion. The manhole and ventilating chamber are built side by side, and together constitute the ventilating shaft. For ordinary sewer-ventilation, the manhole without a side chamber may be utilised as a ventilating shaft, or efficient ventilation can be secured by making a sufficient number of direct openings into the crown of the sewer. Manhole covers can also be utilised as ventilators by in- serting an open grating into them. In cases where the sewer runs parallel with and close to the pavement, it is advisable to carry the ventilating shaft in a sloping direc- tion to an open grating situated in the centre of the street. All these different methods of sewer- ventilation have been carried out in several places at my suggestion with respect to sewers which when first laid were not ventilated, and have been found to answer admirably. The mistake which is often made is to carry out extensive improve- ments of this description during the warm months of summer or autumn. At this period of the year the evolu- tion of sewer-gases is greatest, and as it is evident that it must take some considerable time to construct a large number of ventilating shafts, great complaints are made of the foul effluvia which are discharged through the openings which are first made. All such improvements, therefore, should be carried out during the colder months of the year, when the sewers are better flushed and sewer- gases are not generated so rapidly. With regard to the number of openings, it may be said generally that the terminals of all drains and sewers should be ventilated, and the junctions of branch sewers with main sewers. According to Mr. Eawlinson there should be not less than 18 fixed openings for ventilation, or 1 at intervals not greater than 1.00 yards, for each mile of main sewer. Flap valves, or other contrivances, should be provided for the outlet ends of sewers, to pre- vent the wind from blowing in. In some cases street 298 REMOVAL OF SEWAGE. gulleys, if left untrapped, could be utilised as ventilators. Indeed, the great object of ventilation is by means of numerous openings to so dilute the sewer air as to render it innocuous and imperceptible to the senses. Some ventilators will act as inlets for fresh air, and others as outlets, according to the direction of the wind. There can be no doubt that direct ventilation when properly carried out is the most efficient, and if sewers are pro- perly constructed in the first instance and kept well flushed there should be no nuisance from the ventilators. Main sewers, liable to be affected by the rise of tides or land floods, must be abundantly ventilated, in order that the sewer air may not be forced back into the tribu- tary sewers and drains. To provide for efficient ventila- tion under these circumstances, Drs. Parkes and Sanderson, in their report on the sanitary condition of Liverpool, recommended the erection of lofty shafts, with a sectional area at least half as great as that of the sewers. They condemned the ventilating shafts in use at the date of the inquiry as being too narrow, and ascertained by ex- periment that the Archimedean screw ventilators, with which the shafts were supplied, only aided the extractive power by 20 per cent. (3.) Flushing of Sewers. As offensive discharges of sewer-air are generally due to the formation of deposits, careful attention to systematic flushing is highly essential. The flushing of sewers is effected by damming back the water, and removing the obstruction when a sufficient collection is made, the sudden rush clearing away any deposit that may have taken place. In addition to the arrangements for flushing, which should be provided at every manhole, there should also be a flushing chamber or syphon flush-tank at the head of each sewer and drain, such chambers being flushed either from the mains where there is a public water-supply or from water- REMOVAL OF SEWAGE. 299 carts. If the flushing is carried out from the mains, care should be taken that there is no intimate connection between these and the sewers. Sewers in straight lines, and even gradients from manhole to manhole, can be cleared out by using scrubbers. No water from manufactories of an elevated tempera- ture should be allowed to enter sewers before being cooled, because it accelerates putrefactive changes in the sewage. Blowing off steam from boilers into them is also objec- tionable. With a system of sewerage properly constructed, well ventilated, and regularly flushed, the dangers arising from atmospheric pollution by sewer -gases is reduced to a minimum. Indeed, the amount of impurities in sewer- air under these conditions is so small as to be almost in- appreciable to the sense of smell, and it may be laid down as a rule that whenever foul effluvia are given off, it is an indication that the sewer is insufficiently ventilated, imperfectly flushed, or that it has been badly constructed in the first instance. In exceptional cases charcoal may be used, but it is wrong in principle, as it cannot deodor- ise sewer-gas without impeding the ventilation. For- merly the practice of employing it in ventilating shafts was general, but all who have practical experience in the matter are now agreed that direct open ventilation is the cheapest and most effectual method, and that when pro- perly carried out it does not give rise to nuisance. When charcoal is used, the kind best suited for the purpose is ordinary wood charcoal, broken into small pieces about the size of coffee-beans, and clean sifted. The layer in the tray or basket should never be more than 3 inches deep, otherwise the passage of the air would be almost completely obstructed. Charcoal always acts most effi- ciently when kept dry, but it does not altogether lose its deodorising powers when it becomes damp. Instead of 300 REMOVAL OF SEWAGE. baskets, Mr. Baldwin Latham introduced some time ago a system of spiral charcoal trays for the ventilation of main sewers. But though charcoal may thus be found to be useful in abating the nuisance arising from the effluvia issuing through an exceptionally situated ventilator, it cannot be too strongly urged that the evil of a foul-smelling sewer should be dealt with at its source. If a sewer is old, leaky, or otherwise so imperfect from original faulty construction as to be nothing but an elongated cesspool, the sooner that it is abolished the better. Unfortunately, however, sewers of this description exist in almost every town ; and not only so, but the gravest errors have been perpetrated in laying down house-drains in total ignorance of sound sanitary principles, and with the grossest care- lessness as regards workmanship. (4.) Shone 's Pneumatic System. Some mention ought to be made here of this system, which was first brought to notice at the meeting of the Sanitary Institute of Great Britain at Stafford in 18*78, and has since then received a large and increasing share of attention. It has passed the stage of experiment, and there can be little doubt that it will greatly assist engineers in overcoming many of the diffi- culties with which they have hitherto had to contend, more especially in low-lying and undulating districts, and sea-board towns. By means of sewage ejectors, which are worked by compressed air conveyed in pipes from a central station, where the engine-power may be either steam or water, Mr. Shone proposes to force the sewage along properly-constructed pipes, or sealed sewers as he calls them, to the outlet, or over rising ground. The ordinary gravitating sewers, properly ventilated, and kept properly flushed, are made to discharge into one or more collecting stations according to the size and contour of the town ; and in these stations are placed the ejectors. REMOVAL OF SEWAGE. 301 So soon as the sewage is forced into the sealed mains from the ejectors, all communication, both with the street and house-sewers, as well as with the atmosphere of the town, is completely severed, and the sewage is harmlessly and rapidly hurried on to the outlet. Flat stagnant sewers and deep cuttings may thus be avoided, and pumping in many instances may be dispensed with. The system has been in operation for some time at East- bourne, where it has worked to the entire satisfaction of the Local Board, and it has also been adopted for War- rington, Worthing, and Winchester. It is applicable to mansions and large public buildings as well as to towns, and has recently been applied to the drainage of the West London District Schools. There is no doubt that the system possesses many advantages, and it has been so highly spoken of by eminent engineers that its appli- cation for the removal of existing defects in the sewerage of towns, as well as to new systems of sewerage, will become much more general as it becomes better known. 2. Traps. That too much reliance has been placed by engineers and builders on the efficacy of traps for the exclusion of sewer-air, is becoming every day more and more evident. Up till quite recently no adequate pro- vision was made for drain or sewer ventilation, and the consequence was that mechanical ingenuity became taxed to the uttermost to prevent the pent-up sewer-gases from forcing their way through the terminals of drains which for the most part were situated inside houses. When hot water is poured down a drain, or when a sewer becomes suddenly charged with a large volume of water, as after a heavy fall of rain, the forces which are brought to bear within the sewer are far greater than the resisting power of any trap, and the displaced gases make their escape often at points where they are the most dangerous. There are few traps whose resisting power exceeds that of 302 REMOVAL OF SEWAGE. a column of water an inch and a half in height ; indeed, the greater number of them, as for example common bell- traps, have only a resisting power of about one-quarter of an inch. Besides, it should be remembered that the water in an otherwise very efficient trap will absorb sewer-gas on one side and discharge it but little changed on the other. All traps, therefore, should be regarded as at the best useful auxiliaries only, for in no case will they afford protection against the escape of foul air if proper ventilation be neglected. Some traps, such as the com- mon bell-trap, are worse than useless, because they are readily removed, often forgotten to be replaced, and are easily broken. Many traps, too, and especially those which are supposed to protect the terminals of drains in cellars or basements, are practically useless, because the water in them speedily evaporates and is seldom renewed. Although there is almost an infinite variety of traps, the most useful of them are either of what is called the mid-feather description, or are constructed on the syphon principle. Flap-traps are sometimes used for sewers or large drains, but they are merely hinged valves which permit water to flow in one direction only, and are also intended to prevent the reflux of sewer-air. In the ball- trap, a floating ball is lifted up when the water rises, and when it reaches a certain level the ball impinges on and closes an orifice. All traps constructed on the mid-feather principle have one or more partitions dipping down into the water between the entrance and discharge pipe, and as water stands in the trap to the height of the discharge-pipe, the partition is always under water. What are called D-traps are of this description, and the common bell-trap, with its various modifications, belongs to the same category, The following are illustrations of useful traps. Fig. 15 is an illustration of a mud-intercepting trap, REMOVAL OF SEWAGE. 303 manufactured by Doulton and Co., and by means of the bucket-handle inside is easily cleaned out. Syphon traps may be described as curved tubes, in which the_whole__of the curve should be always full of water. All bath and lavatory pipes should be trapped in this way, even when Fig. 15. Fig. IH.-bimple Gulley Trap. they do discharge on to outside gratings, to prevent the entrance of cold air. Fig. 17 is an illustration of the syphon trap recommended in the Annotated Model By- La ws of the Local Government Board for ventilating and disconnecting house-drains. Amongst good ventilating traps, well adapted for house -drains, may be mentioned Banner's patent house- drain trap, Buchan's patent discon- necting and ventilating drain trap, and the trap known as " The patent Edinburgh air-chambered sewer trap," manufactured by Messrs. Potts and Co. of Birmingham. By adopting one or other of these appliances, the most serious defects connected with house -drainage may be effectually re- moved, provided the drains are well enough laid, in the first instance, to prevent leakage. Fig. 1 8 is an illustration of Gregen's patent air-inlet, manufactured by Doulton and Co., together with trap and ventilating pipe. The raised rim round the shaft 304 REMOVAL OF SEWAGE. prevents the entrance of any dirt into the drain, and the whole apparatus if properly applied will not only effectually disconnect the drains of any house from the sewer but will ensure a constant current of fresh air AIR INLET Fig. 18. through them. At the same time all waste-pipes from sinks, lavatories, or baths, and overflow pipes from cisterns, should be carried outside, and made to discharge on trapped gratings, as previously shown in the Chapter on Dwellings. 3. Water -Closets. The situation, construction, and general arrangement of the water-closets best suited for private houses have already been described in the Chapter on Dwellings. In the crowded districts of large towns, however, the ordinary form of water-closets has proved a failure, partly on account of the complicated character of the contrivances for flushing, but chiefly on account of the carelessness and filthy habits of the poorer classes. For these reasons some special modifications of the usual plan of closet, suited for large collections of people, and whose management may be more under the control of the REMOVAL OF SEWAGE. 305 public authorities, have been devised and introduced into several large towns. The arrangements which have been found to answer best are the trough- closets in use at Liver- pool, the tumbler-closets in use at Leeds and Birkenhead, and what is known as the "Bristol Eject," in use at Bristol. (1.) The Trough-closet may be described as consisting \( of a series of closets communicating with a long trough ^ situated beneath and behind the seats, which receives the excreta from each closet in the series. The lower end of ^ the trough communicates with a drain leading to the j^ ~ sewer by an opening which is closed by a plug. Behind ^ ] the back wall of the closet there is a small space, to f ^ which no one has access but the scavenger, and from ^ a which alone the plug can be raised by means of a handle. \ The scavenger visits daily, empties the trough, washes it out with a hose connected with a hydrant, and again >* ' charges it with water. . As much water is let in as will - ,T W^ V***- VW<4JU A, Ttfttotft^ MJL**U.<> ' cover the excreta received during twenry-TourKours, and so prevent any smell. The closets are kept clean by the ^ p users, and an inspector visits occasionally to see that ' f cleanliness is maintained. Offenders may be summoned, and fined or imprisoned. Dr. Buchanan and Mr. Eaclcliffe, in the report already alluded to, make the following observations with regard to the trough-closets : " Nothing could be more admir- able than the working of the Liverpool arrangement, and f^ nothing could be more marked than the difference between N^ them and what are called water-closets in the poor neigh- bourhoods of London and other large towns ; " and this r favourable opinion is fully confirmed by Mr. Radcliffe in his more recent report. (2.) The Tumbler-closet resembles the trough-closet in its general plan and structure, but differs from it in regard to the arrangements for flushing. At the upper end of x 306 REMOVAL OF SEWAGE. the tumbler- closet trough there is a swinging basin, into which water is constantly trickling, and which is so con- structed that it capsizes whenever it becomes full. In this way the contents of the trough are every now and then washed into the drain, at longer or shorter intervals, as may be deemed necessary. Although these closets are capable of doing good work, it appears from Mr. Kadcliffe's report, and an admirable report written by Mr. Vacher, health officer for Birkenhead, that, owing to want of proper supervision and an insufficient supply of water, they have practically failed. The sanitary flushing-closets, manu- factured by Wilcock and Co., Leeds, with automatic flushing arrangements, would answer much more satis- factorily. (3.) The Bristol Eject. According to Mr. Eadcliffe, this consists of a strongly constructed dip-trap interposed between the privy trunk, as the receptacle is termed, and the drain. It thus admits of the ready extraction of foreign matters which may be thrown in, it is not easily broken, and as it is flushed and kept clean by the servants of the corporation, it is found to answer much better than ordinary water-closets among the poorer classes of large towns. For barracks, prisons, etc., water latrines of a much simpler construction than either of the above answer exceedingly well. An open metal trough roofed in, and with the necessary partitions and doors, receives the excreta, while its anterior upper margin constitutes the seat. In order that the excreta may be constantly covered, the trough should be kept one-third full of water. It should also be well flushed at least twice daily, and the contents allowed to run off into a drain connected with a sewer. A plug or flap-door at the lower end of the trough will be required to prevent the water from draining off during the intervals. REMOVAL OF SEWAGE. 307 There is a further advantage, common to all closets of the trough system, which may here be pointed out. In the event of an epidemic of cholera or enteric fever raging in the crowded courts where these closets are in use, it will be an easy matter to throw disinfectants into the troughs, and thus destroy the infectious power of the alvine discharges. (4.) Intercepting Tanks. This system of intercepting the solids and allowing the liquid part of the sewage to run off into the drains, has been advocated by many, on the grounds that the manure thus collected can be readily utilised, that there is no risk of clogging up the sewers, and that the sewers themselves may be constructed of much smaller dimensions. Many of the fosses perma- nentes and. fosses mobiles on the Continent are constructed on this principle, and in this country a tank has been introduced by Mr. Chesshire of Birmingham, which has been well spoken of by Dr. Parkes, and Dr. Hewlett, health officer of Bombay. The following is the patentee's description of the tank : " The plan or form at present preferred is that of an iron box, large enough to hold the solid part of the excreta of an average household for from eight to twelve months, and yet, when full, within the power of two strong men to lift. This box is 2 feet 4 inches long, by 18 inches wide and 18 inches deep. The pipe from the privy or closet passes into the top of the box, by preference at the opposite corner to the outlet or waste-pipe, which, placed at the bottom of the box, is divided from the main part by a perforated grating ex- tending across the corner and the whole height of the box. Except as to the inlet and outlet pipes, the box is hermetically sealed, though the lid can be readily removed when it is desirable to empty it. The connection of the inlet and outlet pipes to the box can also readily be sepa- rated and re-made without the assistance of the plumber." 308 REMOVAL OF SEWAGE. It is doubtful, however, whether this or any other plan which merely intercepts the solids, can ever be com- mended for extensive use. For, on the one hand, the prevention of the more solid portion of the excrement from entering the drains does not materially lighten the sewage-problem ; and, on the other, the detention of filth on premises, even though it be in close boxes, is wrong in principle, and cannot be regarded as free from danger. Indeed, the advantage above all others which attaches to the water-closet system when efficiently carried out, is the continuous and complete removal of all excremental mat- ters from dwellings. (5.) Urinals. These should be lined with glazed stoneware tiles, or enamelled slabs of smooth slate. They can be kept perfectly clean and inodorous by allowing a small quantity of water to trickle down them constantly. In all towns of any size it is a great desideratum on the score of cleanliness, health, and convenience, to pro- vide public lavatories in suitable localities, supplied with water-closets, urinals, and washhand basins, and they should be provided for the female as well as for the male sex. At Nottingham a ladies' lavatory has recently been provided by the Corporation, which about pays for interest on outlay and attendance, and in Glasgow three such lava- tories have also lately been opened. SECTION II. THE PRIVY OR MIDDEN SYSTEM. From what has already been said, it is obvious that the privy or midden system of old type, with leaky and foetid cesspits behind, is totally inapplicable to populous places. Cesspools and large deep ashpits in connection with privies are equally objectionable, no matter what precautions be taken. To improve the system so as to render it even tolerable, it is essential that the pit should REMOVAL OF SEWAGE. 309 be small in order to secure frequent removal of the con- tents ; that it should be shallow and perfectly water-tight to prevent leakage ; that it should be roofed in, to keep out rain ; that it should be well ventilated ; that it should be easy of access ; that it should be at a safe distance from the house ; and that the contents should be kept dry and inoffensive by means of sifted ashes or other dry refuse. It is not necessary that it should be drained, for if the ashes do not keep the excreta dry the system is a failure. According to Mr. Netten Radcliffe, the only kinds of midden-privies which were found to answer all these re- quirements fairly well are the improved middensteads of Hull and Glasgow. The Hull middenstead consists solely of the space under the closet seat, and its floor is formed by a flag which slopes downwards to the back wall at the ground-level there. The ashes are thrown in through the hole in the seat, and the front board of the seat is movable, to enable the scavenger to get at the contents, which are removed weekly. Privies of this description can be built for about 3. The Glasyow middenstead is proportionately of smaller size than the Hull middenstead, but is extended sufficiently far back from the seat to admit of the ashes being thrown upon the excrement from behind. As several families use one privy, the contents are cleared away every two days. Other schemes, intended to diminish the offensiveness of large middensteads, as observed in Manchester, Salford, Nottingham, and elsewhere, were all found to have practi- cally failed. In Manchester, where many of them were drained into the sewers, it was discovered that the sewers were becoming gradually choked up with sediment. KKMOVAL OK SKWAOK. SECTION III. Tin. PAIL 81 The more common varieties <>\ thin system arc the following : 1. Pails used without preparation (Glasgow). 2. Pails supplied with a deodorant and anti-septi-- (Kochdale, Birmingham, Nottingham, Leeds). 3. Pails lined on the Goux system (Halifax). 4. Pails in which ashes and house-refuse as well as excrement arc deposited (Kdinbnr;_di, Nottingham;. ... l';iil:i into which co;d ;r,he are :rreened above the excrement (Manchester, Salford, Cockermouth;. In order to carry out this system in the most efficient manner, two pails are required ir each closet, one to receive the excreta, and the other the ,-. h- ;,nd house- refuse. The excrement pail may be either n wooden pail or tub, as used at Ilochdale, Nottingham, and Hal i In ; 01 it may be of metal, such as that used in Manchester, Leeds, and Glasgow. In either case it is requisite tli;>i it should be round, so that it can be easily cleaned, ;md !<. u!<, than ordinary pail closet manure mixed with ashes. In a letter dated March 1883, the Medical Officer of Health assures me that the Goux system is extending every year in Halifax, and continues to give every satis- faction. In Manchester, Salfbrd, and other large towns, a dry ash system of excrement-disposal has been combined with 312 REMOVAL OF SEWAGE. a pail system ; and in some places Morrell's patent self- acting cinder -sifting ash -closets have been extensively introduced. As to the kind of closet best suited for the pail system, it is found that a closet somewhat after the im- proved Hull or Glasgow pattern, but with level floor and with space enough to contain the ash-pail as well as the excrement pail, is the cheapest and most convenient. According to Mr. Netten Kadcliffe, " it would be diffi- cult to suggest any great improvement upon the patterns adopted in Rochdale, Manchester, and Halifax. The com- pactness of the plan and the facility with which the pail- closet can be adapted to the varied requirements of old towns in the reconstruction of midden-closets, is most instructively shown in the plans given of adaptations in Halifax." But in all large towns the great difficulty which has to be encountered rests mainly on the disposal and treat- ment of the ashes, refuse, and pail contents after they have been collected. The following is a description of the system carried out in Warrington, and I beg here to express my indebtedness to Mr. Longdin, surveyor of that borough, for the details : (1.) Ashes, etc., collected in ash-tubs. These are dis- charged at the ground-level of the depot, and lifted by an elevator and cast into an automatic cinder-screen, which separates the material into two portions, viz. fine ash and coarser substances. The fine ash is discharged at a point sufficiently high that it can be shot into a cart without labour, and afterwards removed and mixed with such portion of the pail -contents as will furnish a manure sufficient to satisfy the local demand. The coarser materials are discharged into the top of a furnace called a " Destructor," which is almost self-feeding, and all that is required is to break up and remove the clinkers. The KEMOVAL OF SEWAGE. 313 heat generated in the process of combustion passes under and through a multitubular boiler, and generates steam for furnishing the power required for working the whole machinery. The clinkers from the "Destructor" are passed into a mortar-mill, which reduces them to powder, and this is either sold as sand or mixed with lime to form an excellent and tenacious mortar. (2.) Street sweepings, including vegetable and animal refuse. This refuse, which consists mainly of sw.eepings from the markets and streets, is discharged on the ground- level, and raised by an elevator to a platform, and thence passed into a furnace called a " Carboniser," which con- verts all vegetable material into charcoal. The fuel required for heating this furnace consists of a portion of the sifted cinders from the ash-tubs. The charcoal pro- duced is a powerful deodorant, and what is not used for mixing with the pail-contents is sold at 20s. per ton. (3.) Pail -contents. The bulk of these, which have not been mixed with fine ashes or charcoal, are emptied on the ground-level into a covered tank, and are conveyed by means of a chain -pump into an elevated air-tight store - tank. After having ^been mixed with a small por- tion of acid to fix the ammonia, the thicker portion of the material settles to the bottom of the tank. The more liquid contents are drawn off into two "Evapor- ators," which are tall cast-iron cylinders, each containing near its lower end a drum-shaped heater, precisely resem- bling a multitubular steam-boiler. These cylinders are partially filled, and the heating -drums are covered with the thin liquid; steam is introduced into the heating- drums, and the liquid becomes partially concentrated. When the contents have lost by evaporation the greater portion of their water they are drawn off into a machine called a " Firman's Dryer," along with the thick portions of the pail-contents which have settled in the store-tank. 314 REMOVAL OF SEWAGE. ' This machine consists of a steam -jacketed horizontal cylinder, traversed by a steam-heated axis and by steam- heated revolving arms, and furnished with scrapers to keep the inner surface of the cylinder free from accumu- lations of dried excreta. The pail-contents are admitted into the " Dryer " at the consistency of thin mud, and after treatment this mud emerges as a dry powder resembling guano in appearance and quality. The method of working this important mode of con- centration is thus summarised : " The vertical concen- trating vessel first described is supplied with steam direct from the boiler, and the ' Firman's Dryer ' is supplied in like manner. The steam and vapour, however, which are driven off from the concentrating vessel and the ' Dryer,' instead of being allowed to escape into the air or being condensed by cold water, are used to furnish heat to the large or main concentrating apparatus, which is kept boiling at a low temperature. This is effected by con- ducting the boiling below atmospheric pressure in a vacuum which is maintained by an air-pump attached to the steam-engine. This larger vessel is in fact a vacuum pan. The apparatus is so connected with tubes and valves that the 'Firman's Dryer' may also be worked under vacuum if necessary. The whole of the vessels are enclosed. All the steam generated is condensed, and the odour given off during the process is also passed through the ' Destructor ' fire arid destroyed. From the time the liquid material enters the store-tank there is no oppor- tunity for odour to escape into the air, as it is kept closely under cover until it finally emerges as a dry powder. The manure made by this process closely resembles guano in appearance and quality, and is sold at 6 : 10s. per ton at works." After the pails are emptied they are thoroughly cleansed and disinfected. REMOVAL OF SEWAGE. 315 The operations at the depot are conducted without the purchase of any coal, and they are so arranged that in case of any interruption to the new process the old can be continued efficiently and with much less cost than formerly. This process of purification by fire, as it is called, has also been adopted by Birmingham, Leeds, Eochdale, Man- chester, and other towns; and so far it appears to have solved the difficulty of dealing satisfactorily with such refuse of towns as is not disposed of by means of the sewers. The " Destructor " and " Carboniser " have both been devised by Mr. Fryer, of the firm of Manlove, Alliott, Fryer, and Co., engineers, Nottingham ; while Firman's patent " Dryer " is also supplied by the same company. The whole of this process is fully described and dis- cussed in an excellent report on the " Disposal of Kefuse " by Dr. Sedgwick Saunders, Medical Officer of Health to the City of London, published in 1881. In this report Dr. Saunders further recommends that condemned butcher- meat and carcases, after being crushed in a mill called a " Devil," should be treated in a Firman's Drying Apparatus, which separates the fat, and reduces the bone and other tissues to a fine fertilising powder. Whether in desiccat- ing liquid excreta or other foul refuse, the great advantage attaching to this process is that it can be carried on without creating any nuisance. SECTION IV. THE DRY SYSTEM. The difference between what is called the dry system of excretal removal and the pail system depends upon the deodorising and destroying power of the dried earth or other material, which, if used in sufficient quantity, converts the mixture into a uniform and inoffensive mass. 316 REMOVAL OF SEWAGE. 1. Moide's Earth- closet. This consists of a wooden box with a receptacle or pail beneath, a reservoir for the dry earth above, and an apparatus for measuring and delivering the requisite quantity of earth whenever the closet is used. The closet is made self-acting by means of a spring in connection with the seat, or it is worked by a handle as in the ordinary water-closet. It is essen- tial that the earth be previously dried and sifted, that a sufficient quantity be thrown into the pail before the closet is used, and that the same amount be delivered over each particular stool. The quantity requisite for the deodorisa- tion of each stool (inclusive of the urine) is found to be 1J Ib. The slops and the rest of the urine must be re- moved in some other way. This system has been introduced, with more or less success, into several public establishments in this country (Broadmoor Lunatic Asylum, the Manx Lunatic Asylum, Isle of Man, the Beading Workhouse, etc.), at the Wim- bledon Camp, and several villages throughout the country. Its use in India has been very highly spoken of by Dr. Mouatt, late Inspector of Indian Gaols. Dr. Buchanan, in Mr. Simon's report for 1869, makes the following summary with regard to the working of the earth system : " (1.) The earth-closet, intelligently managed, furnishes a means of disposing of excrement without nuisance and apparently without detriment to health. " (2.) In communities the earth-closet system requires to be managed by the authority of the place, and will pay at least the expenses of its management. " (3.) In the poorer classes of houses, where super- vision of any closet arrangements is indispensable, the adoption of the earth system offers special advantages. "(4.) The earth system of excrement -removal does EEMOVAL OF SEWAGE. 317 not supersede the necessity for an independent means of removing slops, rain-water, and soil-water. " (5.) The limits of application of the earth system in the future cannot be stated. In existing towns, favourably arranged for access to the closets, the system might be at once applied to populations of 10,000 persons. "(6.) As compared with the water-closet, the earth system has these advantages : It is cheaper in the original cost, it requires less repair, it is not injured by frost, it is not damaged by improper substances driven down it, and it very greatly reduces the quantity of water required by each household." The agricultural value of the earth excrement, its facility of transport, and variety of application, are also pointed out. The disadvantages of the system are the difficulties of procuring, drying, and storing the earth, particularly in crowded localities ; the special service and attention which the closets require ; the frequent discomfort attending their use when the earth is very dry and powdery ; and the inadequacy of the system as a means of removing the whole excreta and slops. " Add to these circumstances the enormous aggravation of all the difficulties of the plan, when not 50 but 50,000 households have to be provided with the necessary appliances, and induced to work them properly, and we can have no hesitation in pronouncing the dry earth system, however suitable for institutions, villages, and camps, where personal or official regulations can be enforced, entirely unfitted to the circumstances of large towns." (First Eeport of the Rivers Pollution Com- missioners, 1868.) When the closets are properly managed, it appears that the faecal matters are disintegrated, so that after a time no excrement whatever can be detected in the mix- 318 REMOVAL OF SEWAGE. ture. After keeping and drying, therefore, it may be used several times without losing its deodorising and absorbing properties, but much depends on the quality of the earth used at the outset. The suitability of various soils is given in the following order: 1, rich garden mould; 2, peaty soils ; 3, black cotton soils ; 4, clays ; 5, stiff clayey loams ; 6, red ferruginous loams ; 7, sandy loams ; 8, sands. For isolated buildings and small country villages, where there is no difficulty in obtaining suitable earth, and afterwards disposing of it, and where the necessary labour and management can be procured, the system is almost perfect. The closets may either be used as fixtures or as movable commodes, the latter being intended for use in bed-rooms, hospital-wards, etc. 2: Various other modifications of the dry system have been tried or proposed, among which may be mentioned the Carbon Disinfecting and Deodorising Closet of Messrs. Weare and Co., in use in several parts of Liverpool ; the charcoal manufactured from street sweepings by the Uni- versal Charcoal and Sewage Company, Limited, at Salford ; and the charcoal manufactured from seaweed by the -Carbon Fertiliser Company of Glasgow. With regard to the last, Mr. Netten Radcliffe observes that "the examination of the charcoal closets in Glasgow and the vicinity proves, as was to be anticipated, that charcoal properly applied acts as a most effective deodoriser of excrement, and that this action, in receptacles kept dry, persists for an inde- finite period. The assumption, however, that the mixed excrement and charcoal may therefore be safely stored for many months in the vicinity of or within the precincts of dwellings, appears to me to be at least premature." The carbon fertilising process, as patented by Mr. Stanford, has recently been tried at Oldham, but only REMOVAL OF SEWAGE. 319 witli varying success. It consists in absorbing excre- mentitious matter with charcoal, and afterwards drying and carbonising the mixture ; thus producing a continually increasing quantity of charcoal, which may be employed in the manufacture of manure, or for other purposes. The principal product of the destructive distillation is ammonia. Another closet which works well, and which has been highly spoken of by Dr. Carpenter, Professor Corfield, and Lieut-Col. Hope, V.C., is the closet known as the Moser Dry Closet. It is simple, automatic, and certain in its action, and is so constructed that any kind of available absorbent material can be used, such as dry earth, road dust, powdered charcoal, sawdust, etc., and either with or without the addition of chemical disinfectants. Although other appliances might be enumerated in connection with the dry system, it will be sufficient to point out that without proper care and supervision this system possesses no special advantages over the ordinary pail system. With respect to the various systems already referred to, the Committee on Sewage Disposal reported that " the attempts to economise in town-sewering and scavenging by removing human excreta separately has been a failure, the local costs have been increased, and the local nuisances also, in proportion to the time of retention of the excreta before removal ; there is also the inconvenience suffered by trespass on the privacy of the household." SECTION V. LIEURNUR'S AND OTHER CONTINENTAL SYSTEMS. These need only require brief mention. Captain Lieurnur's system may be described as consisting of air- tight iron tanks situated under the streets, which are 320 REMOVAL OF SEWAGE. connected by iron pipes with the closets in the houses. By means of a powerful air-pump worked by steam the sewage is sucked along the pipes to these central tanks, and is afterwards converted into poudrette. Only a little water is used in the closets. The system has been tried in Amsterdam, Leyden, and elsewhere ; but, owing in great measure to its original cost, it has not met with much acceptance. Moreover, it appears to be radically defective in principle, because it is evident that the pipes must become clogged up sooner or later with fsecal matter, and indeed this result is not at all unusual. According to the Seventh Eeport of the State Board of Health of Massa- chusetts there is great complaint of the bad odour from the closets when they are situated inside houses, and in order to obviate this nuisance, the people are in the habit of flushing them with large quantities of water. The consequence is that the sewage becomes so much diluted that it could only be converted into poudrette at a most ruinous cost. The fosses permanentes of Paris, Brussels, and other continental towns, are huge j)its, placed generally under courtyards. They are lined with cement, so as to render them impervious, and are usually ventilated by shafts rising some feet above the roofs of the houses. The con- tents are removed three or four times during the course of the year by air-tight carts (tonneaux), from which the air is exhausted previous to filling, so that the sewage is forced into them through a hose by atmospheric pressure. The closets in connection with the cesspools are almost invariably in a filthy state, from the habit of standing on the seat, which appears to be prevalent in private houses as well as in public places. The system known as fosses mobiles is now adopted in many continental towns, and is a great improvement on the system of fosses permanentes. The fosse mobile is a KEMOVAL OF SEWAGE. 321 closed tub placed on a stand with wheels, and connected by a descent-pipe with the different closets or faiences of a house. When filled it is replaced by another of the same construction. The alfuhrtonnen of the Germans are of a similar description, but in many of the larger towns the bucket or pail under the privy seat is used (Berlin, Leipsic, etc.) SECTION VI. SYSTEMS BEST SUITED FOR EURAL DISTRICTS. In villages where the scavenging is undertaken by the Sanitary Authority, it is just as essential that some uniform scheme of excrement-disposal should be adopted as in towns, but in the great majority of country villages provided with sufficient garden space, public scavenging is not necessary, because the solid refuse can generally be safely disposed of on the premises. The kind of altera- tions, therefore, which may be required to remove privy nuisance, will depend very much upon existing arrange- ments. If, for example, the privy abuts against the house, or is not very far from a well, it should either be removed altogether, or be converted into an earth or ash closet, and be provided with a box or pail to receive the excreta. " Inside a house," as I have said elsewhere, " the only . . kind of closet which can be used without risk to health \ must be a water-closet communicating with a drain or cesspool, or a dry closet of an approved pattern ; but in either case the closet must be detached from any living or sleeping room, and be properly ventilated. In country, villages, however, the closet accommodation, except in a few of the better class houses, is situated outside, and is of every conceivable description. In the older villages it is sometimes represented by a rough wooden erection, with a hole dug in the ground to receive the excreta, or Y 322 REMOVAL OF SEWAGE. more frequently by a sentry-box-looking structure, stuck somewhere near the far end of the garden, and with a stinking leaky cesspit behind. In more modern villages, however, the privy and ashpit or middenstead are found combined ; but as a rule the ashpit is large and deep, leaky and uncovered, so that at all times it is more or less of a nuisance. Then, again, in the few best class houses pro- vided with water-closets, it is generally found that the soil-pipe is not ventilated, and that the closet discharges either into a covered cesspool, from which any gases generated can escape only into the house, or into a village- drain which was not constructed to receive excremental filth. Such, briefly, are some of the more common varieties of closet -accommodation to be met with in country villages, and I need hardly say that the structural defects connected with them are very often a source of nuisance and risk to health. How, then, are these defects to be remedied, legally, in the first place, and with a due regard at all times to efficiency and cost ? Take, for ex- ample, the primitive wooden structure, with the hole dug in the ground to receive the excreta. As a rule, this kind of privy-accommodation is only met with when the cottage itself is old and dilapidated, so that it would be a sheer waste of money to insist on the erection of a new and substantial structure. All that the law demands is to fairly satisfy the requirements of health and decency, and this can be accomplished in the great majority of instances at a very trifling outlay. Let the whole be cleaned out and filled in with fresh gravel or clay, and such other . alterations made that a galvanised iron pail or box can be readily inserted beneath the seat to receive the excreta. This, of course, should be regularly emptied into the garden ; and to obviate nuisance, dry earth or sifted ashes should be thrown into the pail at least once a day, and in sufficient quantity to keep the excreta covered. If the REMOVAL OF SEWAGE. 323 seat is hinged, there will be no difficulty in removing the pail or in throwing the ashes into it without dirtying the seat. Or take the old-fashioned privy, with its foetid cesspit behind. This can be readily converted into an inoffensive privy and ashpit combined, by filling up the cesspit to the level of the ground ; paving or cementing the filled area, walling it in, and covering it as an ashpit ; raising the floor of the privy a step, and with it the seat ; and placing a flag sloping backwards beneath the seat, so that the excreta may be readily covered with the sifted ashes or dry refuse thrown into the ashpit. Or the ash- pit may be dispensed with, and, after filling up the cess- pit, the privy may be readily converted into a pail-closet. To sift the ashes, either a common riddle may be used, or such cinder-sifters as those devised by Dr. Bond of Gloucester, and Mr. Fox of Cockermouth. But whatever alterations may be adopted in addition to those required for privacy and ventilation, the great desideratum is to keep the excreta dry, and prevent undue accumulation. Large, deep, and uncovered middensteads, or ashpits connected with privies, are always a source of nuisance. When they are nearly empty, the surrounding soil drains into them in wet weather, so that for the time being they become open offensive cesspools, and when full they permit of soakage into the surrounding soil. Every ashpit, there- fore, connected with a privy should be little, if at all below the level of the ground ; it should be cemented, or made otherwise water-tight, and should be covered (a sloping tarred wooden covering hooked on to the back of the privy will do), to keep out the rain. Moreover, it should be of limited capacity, to prevent undue accumu- lation, and thereby necessitate frequent removal of the contents. Sometimes, in order to keep the contents more or less dry, the ashpit is drained ; but apart from the liability to chokage of the drain, and the nuisance arising 324 REMOVAL OF SEWAGE. from the admission of liquid excremental filth, drainage of the ashpit should be prohibited, because, if the ashes do not keep the excreta dry and inoffensive, the system is a failure." " From these few remarks it will be observed that I advocate every possible latitude as regards the way in which nuisances connected with privy accommodation may be removed. In villages, however, for which public scavenging is considered necessary, there is no doubt that some uniformity in the nature of the alterations must be carried out, and I am of opinion that one or other of the pail systems would answer best; as, for example, the Goux system. In rural districts, provided with urban powers, the kind of privy-accommodation supplied for new houses should be carefully considered and enforced ; and in one of my own districts I may mention that the closet known as Moser's closet is the one approved by the Sani- tary Authority, although I need hardly say there are many other patents which would answer equally well. Indeed, for new houses any patent of the kind is much cheaper than the old-fashioned privy with its huge deep ashpit, and, what is more, it is a sure preventive against any serious nuisance. But for old-fashioned country villages, where alterations of a limited kind have to be carried out, I do not think that any of the excellent patents to which I have referred are suitable, partly because they are some- what expensive, and partly, too, because I find that from neglect they do not afford any advantages over the ordi- nary pail-system. In short, there is no dearth either of adequate appliances or material ready at hand to answer all reasonable sanitary requirements, if we could only get people to make proper use of them." (See the Author's pamphlet on Sanitary Defects in Rural Districts, and how to remedy them.) REMOVAL OF SEWAGE. 325 SECTION VII. DISPOSAL OF SLOPS. The term slop - water, as commonly understood, is used to indicate ordinary household liquid refuse ex- clusive of faecal matter. For the most part it consists of urine, soap-suds, and the foul washings from premises generally ; and though it may not be considered as offensive as town -sewage, it frequently gives rise to serious nuisance when it is allowed to fester in rubble drains or stagnant ditches, and is a constant cause of well-pollution in country districts. In all sewered towns the slops are of course removed by the ordinary drains and sewers, and even in most villages it is fonnd that their disposal is in great measure a question of village- drainage in the first instance. But, unfortunately, this village-drainage is so radically defective in the great majority of instances, that pollution of air and water is alike common. The shallow road drains which were intended, when first laid down, to carry off the surface water, and which, for the most part, are generally con- structed of common drain pipes, or loosely laid bricks or stones, have been converted into common sewers by conveying into them the badly laid and open -jointed drains leading from almost every house, or group of houses, in the village. If there be a watercourse near the village the drainage discharges into the stream by one or several outlets, as the case may be, and with what results it is needless to specify. Should it happen, how- ever, that the village is some distance from a stream, then it is found that the slops discharge into open ditches by the roadside, or into field-ditches in the immediate neighbourhood of houses, and thereby often give rise to filthy nuisances in every direction. This description, it is true, only applies to the worst drained villages ; but in almost all of them some of these defects 326 KEMOVAL OF SEWAGE. are to be met with. Shallow, unevenly laid, and leaky drains are especially common ; and as these are not only liable to pollute any wells which may be near them, but in consequence of the want of proper means of flush- ing permit of filth-accumulations, which give off noxious effluvia, they are a source of constant danger. And this description, it should be remembered, ap- plies to villages in which water-closets do not exist at all, or are very rare, so that the whole of the nuisance may be said to depend upon the disposal of the slop- water. The question, therefore, at once arises whether in any given case a new system of drainage will be required, or the existing system improved to remove nuisance, or whether the slops cannot be satisfactorily disposed of in some other way. If common gutters, as some recommend, are to take the place of drains, it is clear that all the old defective drains must first be taken up and filled in with sound material, and that the gutters themselves should be properly channelled and kept clean. But in the present condition of village-roads, with badly- laid side-paths, it is just as evident that these open gutters would be a constant source of nuisance, and hence, in compact villages, or villages of any size, the question of the disposal of slops, is, as I have already said, a question of drainage, and need not be further dis- cussed here. It is sufficient to state that all such drains ought to be well laid, well ventilated, and kept properly flushed, especially in warm weather, by means of a hand water-cart, which could be easily wheeled about by the road-man. (For further remarks, see next chapter.) As regards scattered houses, or -groups of houses which create nuisance by draining into open roadside ditches, such nuisance may be obviated by using the slops in the garden, and if there be not sufficient garden space, I know of no better mode of dealing with them REMOVAL OF SEWAGE. 327 than that devised by Dr. Bond, which consists in the use of a precipitating slop-tub with a filter. Where there is sufficient garden space, and the ground slopes away from the house, the most satisfactory way of treating them is by sub-irrigation, and the use of Field's syphon flush- tank, but care must be taken that the sub-irrigation drains are laid at a safe distance from the well. Some- times the drains lead into what is called a dumb-well ; and provided there is no well for drinking-water near, and the dumb : well is ventilated and regularly cleaned out, this may be regarded as a tolerably safe and ready method of dealing with the difficulty. But the multipli- cation of dumb-wells or cesspools in villages, as in towns, is always attended with danger, and ought to be avoided as much as possible. SECTION VIII. PUBLIC SCAVENGING. Except it be in small scattered communities, and perhaps purely agricultural villages, it may be laid down as a rule that no semblance of local cleanliness can be maintained unless the scavenging, as well as the sewerage, be undertaken by the Sanitary Authorities ; for, in pro- portion as dwellings become aggregated, and populations increase, it becomes more and more difficult for individual householders to dispose of their refuse separately. Fortu- nately, in the great majority of agricultural villages there is sufficient garden space attached to the houses to permit at all events of the safe disposal of the solid refuse on the premises without creating nuisance, or for exceptional cases there need be little difficulty in arranging for its disposal on some closely adjacent land. Arrangements, for example, may generally be made with some neighbour- ing farmer, or, as Mr. Haviland has suggested, any excep- tional difficulties which may arise, from want of sufficient 328 REMOVAL OF SEWAGE. garden space might be overcome if Sanitary Authorities were to provide a spare corner of ground, known as " the muck acre" to which householders could remove their solid refuse. But whenever, in any village or town, these difficulties are ascertained to be at all common, it then becomes the duty of the Sanitary Authority of the dis- trict to undertake the efficient scavenging of premises, either through their own officers or by contract, and in case of refusal or neglect, they can be compelled to do so by order of the Local Government Board. In any case, however, the Sanitary Authority is virtually responsible for the cleanliness of its district, either by enforcing the provisions of the Public Health Act for the prevention of nuisance arising from filth-accumulation on individual premises in places to which scavenging does not extend, or by systematically preventing the occurrence of nuisance in places where public scavenging has been introduced. As regards the general details of public scavenging, much will depend upon local circumstances, and upon the method of excretal removal which may be found to prevail in any particular town. Where the old-fashioned midden system is still allowed to be carried on, the house- refuse is mixed with the excreta, and both are carted away together. In the majority of towns, however, the ashes and other solid house-refuse must be collected and removed by a separate system, which necessitates the use of dust pails or bins, and the daily or frequent visit of the scavenger's cart. For dwellings occupied by single families the dust box or pail answers very well, it being large enough to contain the dry refuse collected during the twenty-four hours ; and as it is emptied into the scavenger's cart at a stated time daily, any accumulation about the premises is prevented. But in crowded parts, where families live in separate tenements, the whole of the ashes and dry refuse is usually, in the first instance, REMOVAL OF SEWAGE. 329 emptied into a common dust-bin, and afterwards carted away when the bin becomes full. In this case it is necessary that the bin should be roofed in, in order to keep the contents dry, and that it should be well ven- tilated. No slops or excrement should be allowed to be thrown into it, because the former excite fermentation in the vegetable and animal matters contained in the refuse, and the latter renders the contents offensive. It need scarcely be added that, in a sanitary point of view, dust- bins should be frequently and regularly emptied. In large towns where the pail system of excreta! removal is carried out, the excrement -pails should be removed in specially covered vans, and the ashes and dry house-refuse in separate carts. The following is Mr. Netten Kadcliffe's description of the system of scavenging as carried on at Eochdale : " The town is divided into six districts for the pur- poses of removal, and the dry house refuse is removed at // the same time as the excrement, a dust-cart accompany- f ing each night-soil van for the purpose. The removal is all effected during the ordinary working hours of the day, the vans commencing their rounds at 7.0 am., and ending at 5.30 p.m. Each night-soil van makes five rounds daily. It leaves the yard laden with clean empty pails, each pail containing a quantity of a ' disinfectant/ and returns carrying the pails containing excrement, for which the empty pails have been substituted. The pro- cess of substitution is effected by the scavengers with- drawing from beneath the closet seat the pail containing excrement, covering this up with the lids already de- scribed, removing it to the van, an empty pail being left in its place, and on placing the pail in the van sprinkling over the outer lid a little carbolate of lime. The ash- tub is then carried to the dust-cart, and its contents simply tilted into it. Each pail closet is numbered and 330 REMOVAL OF SEWAGE. registered, and the scavengers proceed from closet to closet systematically, according to the portion of their district within the day's beat, revisiting at the end of each round the closets from which the pails had been removed, and those, if any, which had been omitted. The greatest number of omissions for any one month in the whole town has been 42, for any one week 14. Each Monday the scavenger's returns are balanced, and a supplementary van with dust-cart sent out to rectify omissions. In the case of lodging-houses and closets used by several families the excrement-pails are removed twice or thrice weekly." In scavenging old-fashioned midden-steads and privies, the nuisance is so abominable that the soil-cart can only make its rounds during the night-time, and even then the stench is so horrible that the air of every street or court along which the cart passes becomes for the time being positively dangerous to breathe. People who are out late at night may sniff these carts a long way off, and when they do so they generally beat a hasty retreat. One very important branch of scavenging in urban districts is directed to the cleaning of streets and back courts, many of which are so badly constructed that it is next to impossible to prevent filth -accumulations. Gutters are often so unevenly laid, that after rain or flushing there are small stagnant pools to be seen throughout their whole extent. The surfaces of maca- damised streets, again, are being constantly pulverised, and give off clouds of dust containing large quantities of decomposing animal and vegetable matter in dry weather, or are covered with liquid mud when it is wet ; while paved streets present numerous interstices, which cannot be efficiently cleaned out even when scrubbing-machines and flushing are both used. There is no doubt, therefore, that the new plan of street construction which has lately REMOVAL OF SEWAGE. 331 been introduced into some parts of London and other large towns, whether it be wood-pavement or asphalt, and preferably the former, will not only prove to be economical in many ways, but will also be productive of great sanitary advantages. Tar-asphalt, if properly laid, is especially applicable to side paths, back courts, and narrow streets, where the traffic is inconsiderable, because it is cheap, durable, non-absorbent, and washable. 332 PURIFICATION AND UTILISATION OF SEWAGE. CHAPTEK XII. PURIFICATION AND UTILISATION OF SEWAGE. IT has already been shown, in the previous chapter, that of all methods of sewage -removal, the water-carriage system is the one which best meets the requirements of large towns. It is the speediest, cleanest, and, in the long run, the most economical, method which can be employed on an extensive scale, and its general sanitary advantages are now placed beyond dispute. But no sooner had this difficult hygienic problem been solved by engineering skill than another of even greater difficulty arose. The eagerness of early sanitary reformers to get rid of human refuse at any cost blinded them to the fact that, by pouring sewage into the nearest watercourse, they were merely removing the evil from one place to take effect somewhere else. No consideration was paid to the probable results of the method on the future water- supply of increasing populations, nor to other serious con- sequences which speedily began to declare themselves. Rivers were in reality converted into sewers, and the communities down stream, while they loudly complained of the annoyance and danger to health, added to the nuisance by following the general example. After a time it was discovered that the mouths of navigable rivers were being silted up, that valuable stocks of fish were destroyed, that water-supplies were contaminated, and that riparian rights were in every sense grossly violated. Such were some of the more important evils PURIFICATION AND UTILISATION OF SEWAGE. 333 resulting from river-pollution, and eventually legal prohi- bitions were issued in many places to prevent their con- tinuance. These prohibitions have multiplied, until the sanitary authorities throughout the country are at last compelled to purify the sewage of towns before it is dis- charged into any watercourse at a distance from the sea, or run the risk of incurring legal penalties ; while the Eivers Pollution Act of 1876 absolutely prohibits any new drainage- works which may in future be carried out from discharging into any river or stream without pre- vious purification. Meanwhile there has been an increasing number of economists who have rightly maintained that sewage was not only wasted, but worse than wasted, when discharged into rivers, and that, on account of its manurial value, its proper destination was the soil. Hence has risen the larger question of the utilisation of sewage, the merits of which will be best understood by considering first the composition of town-sewage. SECTION I. TOWN-SEWAGE. In addition to excretal matters, town-sewage contains the effete products of various trades and manufactures, animal and vegetable dtbris, mineral detritus from roads and streets, and the like, all of which are held in suspen- sion or solution by an amount of water varying according to the water-supply in the first instance, and depending, in the second place, on the rainfall and amount of sub- soil-water entering the sewers at different times of the year. This varyiug amount of water is one of the chief difficulties to be encountered in the utilisation of sewage, and, apart from other considerations, it has led Mr. Men- zies and other eminent engineers to recommend the intro- duction of the pipe-sewer system, which has already been described, into all towns where sewerage-plans have yet to 334 PURIFICATION AND UTILISATION OF SEWAGE. be carried out. The sewage delivered from pipe-sewers, consisting almost exclusively of excretal matters, slops, and the water-supply, can of course be readily estimated in all cases, and is much more easily dealt with. But with common drain-sewers, which receive in addition the rainfall and subsoil- water, not only is the extent of dilu- tion much greater, but it is constantly varying in amount. Thus, to quote the data given in the Third Eeport of the Sewage of Towns Commissioners (1865), it is con- sidered that 6 tons per head per annum ( = 36 gallons per head daily) is the average amount of normal or dry- weather sewage in the metropolis ; but this amount is further increased by the rainfall and subsoil-water from two-thirds to an equal volume. With pipe-sewers, however, the amount of sewage equals the amount of water-supply, and in towns supplied on the constant system, this ought not to exceed 20 gallons per head daily, or about 33 tons per head per annum. In the face of such considerations as these, the sanitary and practical importance of Mr. F. 0. Ward's famous alliterative dogma of "the rainfall to the river, and the sewage to the soil," becomes at once apparent. But, with either system of sewers, the value of the sewage may be said to depend entirely on the excretal matters, and the amount and relative value of these will be gathered from the following data : The subjoined table represents, as the result of numerous analyses, the average amount and composition of excretal matter discharged by a male adult daily : Fresh Excrements. Dry Substances. Mineral Matter. Carbon. Nitrogen. Phosphates. Faeces Urine Oz. 4-17 46-01 Oz. 1-041 1735 Oz. 0-116 0-527 Oz. 0-443 0-539 Oz. 0-053 0-478 Oz. 0-068 0-189 Total 5018 2776 0-643 0-982 0-531 0-257 PURIFICATION AND UTILISATION OF SEWAGE. 335 In a mixed population, the actual amounts per indi- vidual will obviously be considerably below this average, and, according to Dr. Parkes, they may be estimated at 2J oz. faecal matter and 40 oz. urine daily, an estimate which gives 25 tons solid fseces for every thousand in- habitants annually, and 91,250 gallons of urine. But the above table also shows that the manurial value of the urine voided in the twenty-four hours greatly exceeds that of the fasces passed in the same time. Indeed, the relative value, as determined by numerous analysts, is approximately as 6 to 1. The actual value of both urine and faeces in sewage has been estimated at 6s. 8d. per individual per annum, supposing that 10 Ibs. of ammonia is a fair estimate of the amount voided in that time. When the sewage averages 24 gallons daily per individual that is, 40 tons per head per annum its money value, according to this estimate, would be 2d. per ton, and the value per ton will decrease in proportion to the rate of dilution above this average. It may be added that this estimate corresponds very closely with the money value of average sewage given in the First Eeport of the Eivers Pollution Commissioners (1868); for it is there stated that the " value of the dissolved constituents in 100 tons of average sewage is about 15s., while the suspended matters only contain about 2s. worth of them." In other words, 100 tons are worth l*7s., or about 2d. per ton. These monetary details are quoted here because they largely affect the question of utilisation of sewage, and have more or less influenced the various plans which have been proposed or carried out in this direction. 336 PURIFICATION AND UTILISATION OF SEWAGE. SECTION II. SCHEMES FOR THE PURIFICATION AND UTILISATION OF SEWAGE. These have generally been classified under the sepa- rate headings of precipitation, nitration, and irrigation processes, and the more important of them are as fol- lows : 1. Precipitation processes. In all of these processes the main object in view is the purification of sewage by the introduction of chemical agents. The dissolved matters are precipitated to a greater or less extent, and can therefore be separated along with the suspended matters, while the effluent water is supposed to be in a sufficiently pure state to allow of its being discharged into a stream or river without producing any serious degree of pollution. It is needless to say that many of them have proved to be signal failures, chemically as well as financially. Fictitious values 'were given to the resulting manure, and some of the schemes, which otherwise might have proved fairly successful, were simply ruined by being made stock -exchange speculations. Indeed, it cannot be too widely known that, no matter what pro- cess may be adopted, Sanitary Authorities must be pre- pared to pay a subsidy for the chemical treatment of their sewage, because it is now clearly established that the manure, or whatever other products may be obtained, will in no case pay, or nearly pay, for the cost of purifi- cation. Several of the following processes have been tried and failed, while others are still on trial, and they are given here rather to show what has been attempted in this direction, than as selected instances of success or failure : PURIFICATION AND UTILISATION OF SEWAGE. 337 (1.) Precipitation ly Lime. This process was at one time carried out on an extensive scale at Blackburn, Leicester, and Tottenham. It consists in mixing the sewage at the outfall works with a certain proportion of cream of lime, when a copious precipitate takes place, which may be sold as manure or converted into bricks. The supernatant fluid flows off in a comparatively clear though milky condition, but contains about half the putrescible matter of the sewage, -and a great proportion of the fertilising constituents. The plan has been pro- nounced by the Eivers Pollution Commissioners to be a conspicuous failure, " whether as regards the manufacture of valuable manure, or the purification of the offensive liquid." At Northampton a modification of this process, by the addition of iron perchloride and subsequent filtration through calcined iron ore, has also been tried, but with little better results. Other salts, such as salts of zinc and manganese, and carbolates of lime and magnesia, have been proposed as adjuvants to the lime-process, but they all fail in separating the ammonia and other manur- ing material. They disinfect the sewage for the time being, but do not prevent subsequent decomposition. (2.) Myth's process consists in the addition of a salt of magnesia and some lime superphosphate, or super- phosphate of magnesia and lime water, with the view of purifying the sewage by the formation of the triple phosphate of magnesia, ammonia, and water. Such a precipitate, however, can only take place in water con- taining an excess of ammonia ; so that the whole process, while being more costly than others, was found to be as inefficient. (3.) In Holders process, a mixture of iron sulphate, lime, coal-dust, and clay, is added to the sewage, but it z 338 PURIFICATION AND UTILISATION OF SEWAGE. fails to remove the nitrogenous matters in solution, and indeed increases their amount by dissolving some of the suspended constituents. (4.) Bird's process, which was tried at Cheltenham, but abandoned, consists in the addition of crude sulphate of alumina, and subsequent filtration through coke. The sulphate of alumina was obtained by treating pulverised clay with strong sulphuric acid. In this and Stotherd's process, which somewhat resembles it, the effluent liquid was not found to be sufficiently purified for admission into a river without creating a nuisance. (5.) The " A B C" or Sillars process. This process, which attracted so much attention some few years ago, had a prolonged trial at Leamington on an extensive scale, and was ultimately pronounced to be a failure. It consisted in adding a mixture of alum, blood, clay, char- coal, a salt of manganese, and other ingredients, to the sewage as it entered the works. A precipitate was thus obtained, which settled to the bottom of the tanks in the form of a soft black mud. This was afterwards pumped up into receptacles, from which it ran into centrifugal drying machines, or was removed into drying chambers. But in either case it was subsequently spread out on the ground to complete the drying process, and the mass was from time to time sprinkled with sulphuric acid to fix the ammonia. It would appear, from the conclusions of the Eivers Pollution Commissioners, that, though it was superior in some respects to the processes already described, it was nevertheless an inefficient purifier. It is but right to state, however, that the process has recently been much improved, and is now carried on successfully at Aylesbury (Sanitary Record, 1880). (6.) Tlie Phosphate process, as proposed by Messrs. PURIFICATION AND UTILISATION OF SEWAGE. 39 Forbes and Price, consists in adding to the sewage a solution of the native phosphate of alumina, dissolved in sulphuric or hydrochloric acid, and diluted in water. The resulting manure has been estimated by Dr. Voelcker at 7 : 7s. per ton. The effluent water is clarified and disinfected, but not by any means freed from putrescible or fertilising matters, and the originators of the process have themselves pointed out that it is only intended as a preliminary step to irrigation, where that can be carried out. Where irrigation is impossible, the process is com- pleted by adding milk of lime, to precipitate the phos- phates in solution. The process generally has been favourably reported on. (7.) In HilUs process the mixture consists of lime, tar, calcined magnesium chloride, and some other substance not named. The lime is slaked, and the tar added while it is hot. The whole ingredients are subsequently mixed with water, and flow through a large tap into the tank which receives the sewage. Here precipitation takes place, and the sewage, completely deodorised, passes into a second tank, where the deposit settles. The effluent water is afterwards filtered through a charcoal basket into a third tank, is received into a fourth, and over- flows from this into a small brook. The working ex- penses of the process are small, but the manure is not valuable. (8.) General Scott's process differs from others already described, in the introduction of the chemicals into the sewer at some considerable distance from the outfall. The precipitating agents consist of lime and clay properly pulverised, and the motion of the sewage in its onward flow ensures their thorough admixture with itself before it reaches the outfall. The resulting sludge which is formed, instead of causing any deposit in the sewer, as 340 PURIFICATION AND UTILISATION OF SEWAGE. some anticipated, acts rather as a scouring agent, and keeps the sewer clean. When received into the outfall tanks, the sewage is found to be deodorised, and here the suspended matters are deposited. These are subsequently removed to be dried and burnt, and are thus converted into a useful cement. The drying process, it appears, is not attended with any nuisance. The British Association Sewage Committee have reported favourably on the whole process, as solving one of the difficulties of the sewage question, namely, the separation and deodorisation of the offensive ingredients in an efficient manner, at a comparatively small cost, and of easy application on a large scale. The effluent water, according to the Committee's analysis, contains rather more than two-thirds of the chlorine and of the dissolved nitrogen of the sewage. It is therefore too valuable to be wasted, and too impure to be discharged into a river, and can only be properly dealt with by irrigation. General Scott's process has been carried on at Ealing, West Ham, and Birmingham. (9.) WTiitthread's process, which has also been favour- ably reported on by the British Association Committee, consists in adding to the sewage a mixture containing two equivalents of dicalcic phosphate, one of monocalcic phosphate, and a little milk of lime. The resulting pre- cipitation was found to be very rapid, and the supernatant fluid clear and inoffensive. Suspended matters were completely removed, and the organic nitrogen nearly so. It was considered by the Committee that the manure would be valuable, as it contained a large amount of lime phosphate and 3 per cent of ammonia. As the effluent fluid contained phosphoric acid and ammonia it would be suitable for irrigation. (10.) Dr. Andersons process, first tried at Nuneaton, PURIFICATION AND UTILISATION OF SEWAGE, 341 has been carried on much more successfully at Coventry. It consists in adding an impure sulphate of alumina, made by dissolving aluminous shale in sulphuric acid, to the sewer water, which is kept constantly stirred, and which afterwards flows into a series of settling tanks. The whole of the machinery is admirably planned, and the effluent, especially after it has passed through an adjoining filtering area, is very clear and fit to be dis- charged into any river. The resulting manure does not command a ready sale, and the works were carried on at considerable loss. Some few years ago, the works were taken over by the Corporation, who pay the Company a fixed sum annually. 2. Filtration processes. (1.) Simple Filtration. In this process the sewage is merely strained or screened, so that, although almost all the suspended matters are removed, the effluent fluid is not by any means purified. The mud which collects at the bottom of the filtering tanks is generally mixed with the town ashes and sold as manure. (2.) Carbon, as in Weare's process, has been tried to purify sewage by filtration, but it does not appear to have been very successful. Very possibly, if it could be obtained at a cheap rate and the filtration were made intermittent, it would be found to answer with small quantities of sewage where land cannot be procured. A cheap kind of carbon is now manufactured for this pur- pose, called Sanitary Carbon. (3.) Upward Filtration. This process was at one time carried on at Baling, but the results were not satis- factory. (4.) Intermittent Dovmward Filtration. Amongst the 342 PURIFICATION AND UTILISATION OF SEWAGE. numerous important experiments conducted under the direction of the Eivers Pollution Commissioners, there were none attended with better results than the filtration of sewage through a considerable depth of soil. The ex- periments were made on sand, on a mixture of sand and chalk, and on different soils. The results varied a good deal according to the quality of the soil, but in all of them it was found that the suspended matters were entirely removed, and that the organic carbon and nitrogen were greatly reduced. According to the report of the Com- // missioners, " These experiments also show that the process of purification is essentially one of oxidation, the organic matter being to a large extent converted into carbonic acid, water, and nitric acid ; hence the necessity for the continual aeration of the filtering medium, which is secured by intermittent downward filtration, but entirely prevented by upward filtration." The process was for some time carried on at Merthyr Tydfil, according to the plans of Mr. Bailey Denton, C.E. ; and the following abstract from the report of the British Association Sewage Committee will afford a sufficient description of the various details and the results : The filtering area or farm was about 20 acres in extent, and consists of a very porous gravelly subsoil, covered with vegetable mould. It was pipe -drained to the depth of about 7 feet, the drains conveying to the lowest corner, where the effluent water was discharged into a small stream leading into the river Taff. The area was laid out in square beds, intersected by paths, along which were constructed the main carriers, which received the sewage from the outfall sewer, where it was screened through a bed of clay, and distributed it over the beds. In order to supply the sewage on the intermittent system, the area was divided into four equal portions, each portion receiv- ing the whole of the sewage for six hours in succession, PURIFICATION AND UTILISATION OF SEWAGE. 343 and thus leaving an interval of eighteen hours for rest and aeration of the soil. The surface of the land was cultivated to a depth of about 18 inches, and was laid up in ridges to allow of the sewage running down the furrows. The ridges were planted with cabbages and other vegetables. The results of the process, as stated by the Committee, were highly satisfactory. All the suspended matters were removed, and the ammonia and nitrogenous organic matters were almost completely oxidised, so that they escaped in the effluent water as nitrites and nitrates. They added, however, that though the sewage was thus efficiently purified, the process could not be regarded as one of utilisation. Since that report was published in 1872, additional land has been obtained to the extent of 230 acres, and the intermittent downward filtration process has been supplanted by simple irrigation, in order that better re- turns might be obtained. The requisite extent of filtering area, as estimated by the Eivers Pollution Commissioners, is 1 acre drained to a depth of 6 feet for every 3300 of the population ; but this ratio must vary according to the nature of the soil. The soil should be porous and the surface have an easy slope. At Kendal, with a population of 13,700, this method has been successfully carried out on an area of 10 acres. 3. Irrigation. It is now generally conceded that this is the only process which fully meets all the requirements attaching to the disposal of sewage ; in other words, it is the only one which, while it purifies the sewage efficiently, realises the highest profits, and may be carried on without creating any nuisance or detriment to the health of the neighbouring inhabitants. But in order that the process may be carried out satisfactorily, it is necessary 344 PURIFICATION AND UTILISATION OF SEWAGE. (1.) That the acreage be sufficient. This will depend in great measure on the looseness or porosity of the soil ; hence to lay down as a rule that 1 acre should be allowed for every 100 inhabitants, which is the estimate usually given by engineers, is manifestly illogical. (2.) The land to be irrigated must be drained, and stiff clayey soils broken up and mixed with ashes, sand, or lime. (3.) The surface must be irrigated on the intermittent system, to ensure sufficient aeration of the soil. (4.) The ground should be laid out in broad ridges and furrows, the sewage being conveyed along the tops of the ridges in open carriers, and made to flow gently down the slopes by inserting temporary sluices in regular suc- cession and at regular intervals. At Breton's Farm, near Eomford, the breadth of the ridge is 30 feet, giving a slope of 15 feet on either side of the carriers. At Lord Warwick's Farm near Leamington, Mr. Tough, the man- ager, informs me that the ridge varies from 50 feet wide, according to circumstances. (5.) There must be a rotation of crops such as Italian rye -grass, peas, maize, different roots, cabbages, etc., and where land is plentiful, it always pays to let portions of it rest for a time for the growth of cereal crops. (6.) The sewage should be delivered in a fresh state, and freed from the coarser portion of its suspended matters. This may be effected either by precipitation, filtration, or screening. At Lord Warwick's farm, the borough of War- wick farm, and the Rugby farm, the sewage is simply screened and delivered fresh on to the land. Such, briefly, are the principal details connected with sewage-farming, and it is the neglect of one or more of them which has brought so much opprobrium on the system. If the irrigated soil becomes water -logged and swampy, the fault lies with the engineering and manage- PURIFICATION AND UTILISATION OF SEWAGE. 345 ment, not with the system. Or, again, if the farm becomes a nuisance, it is because the sewage is not properly dis- tributed, or the carriers kept free from deposit. The comparative results of the different processes of purification are stated by the Kivers Pollution Commis- sioners as follows : Average Results. Percentage of Dissolved Organic Pollution removed. Percentage of suspended Or- ganic Impurity removed. Organic Carbon. Organic Nitrogen. Chemical processes Upward filtration . . Downward nitration . Irrigation .... 28-4 26-3 72-8 68-6 36-6 437 87-6 817 89-8 100- 100- 977 This table shows that, in order to obtain the best purifying results, irrigation should always be combined with intermittent downward filtration. With regard to 'towns where a sufficiency of land cannot be procured for irrigating purposes, the process of downward filtration, as carried on at Kendal, should be adopted, and, in either case, the ashes and other town-refuse can be largely used in clarifying or disinfecting the sewage before it is de- livered on the filtering ground. Trade or manufacturing pollution must be treated according to the nature of the pollution. Where no sufficient amount of land can be procured, as in the case of numbers of large inland towns, recourse must be had to purification by some chemical process, but in many instances the difficulties are so enormous, that the pollution of neighbouring streams cannot be prevented unless at a cost which would irretrievably ruin commercial enterprise. Even were all trade-refuse and sewage excluded 346 PURIFICATION AND UTILISATION OF SEWAGE. from streams, the mere surf ace -wash ings of large towns are sufficient of themselves to convert many of them into foul rivers, which no legal enforcement of riparian rights nor any number of Eivers Pollution Bills can ever render pure. Indeed, at Birmingham, Leeds, and other inland towns, the effluent is much purer than the filthy streams into which it discharges. Sanitary reformers are too apt to forget that, though streams and rivers may, and often do, prove valuable sources of water-supply, they are never- theless the natural drainage outfalls of the country, and while many of them may be preserved from injurious pollution, there are numbers of others doomed to such an amount of pollution that, no matter what preventive means may be adopted, fish can scarcely live in them, and their turbid waters, however carefully purified, can never be safe to drink. It is evident, therefore, that with regard to river pollution, the special circumstances of every large town involved in sewage-difficulties must be taken into account, and that no hard-and-fast rule can be enforced by Act of Parliament which shall be applicable to all alike. The following were the conclusions adopted by the Executive Committee of the Conference on the health and sewage of towns, held under the auspices of the Society of Arts in May 1876, and they are appended here as afford- ing a full and fair exposition of the various aspects of this difficult problem of sewage treatment and utilisation : " 1. In certain localities, where land at a reasonable price can be procured, with favourable natural gradients, with soil of a suit- able quality, and in sufficient quantity, a sewage farm, if suitably conducted, is apparently the best method of disposing of water- carried sewage. It is essential, however, to bear in mind that a profit should not be looked for by the locality establishing the sewage farm, and only a moderate one by the farmer. " 2. With regard to the various processes based upon subsidence, precipitation, or nitration, it is evident that by some of them a suf- PURIFICATION AND UTILISATION OF SEWAGE. 347 ficiently purified effluent can be produced for discharge, without injurious result, into watercourses and rivers of sufficient magnitude for its considerable dilution ; and that for many towns, where land is not readily obtained at a moderate price, those particular processes afford the most suitable means of disposing of water-carried sewage. It appears, further, that the sludge, in a manurial point of view, is of low and uncertain commercial value ; that the cost of its conver- sion into a valuable manure will preclude the attainment of any adequate return in the outlay and working expenses connected therewith, and that means must therefore be used for getting rid of it without reference to possible profit. " 3. In towns where a water-carried system is employed, a rapid flow, thorough ventilation, a proper connection of the house drains and pipes with the sewers, and their arrangement and maintenance in an efficient condition, are absolutely essential as regards health ; hitherto sufficient precautions have rarely been taken for efficiently ensuring all the foregoing conditions. " 4. "With regard to the various dry systems, where collection at short intervals is properly carried out, the result appears to be satisfactory, but no really profitable application of any one of them appears as yet to have been accomplished. "5. The old midden or privy system in populous districts should be discontinued, and prohibited by law. " 6. Sufficient information was not brought forward at the Con- ference to enable the Committee to express an opinion in regard to any of the foreign systems. " 7. It was conclusively shown that no one system for disposing of sewage could be adopted for universal use ; that different locali- ties require different methods to suit their special peculiarities ; and also that, as a rule, no profit can be derived at present from sewage utilisation. ** 8. For health's sake, without consideration of commercial profit, sewage and excreta must be got rid of at any cost." To those who are interested in the monetary details of the question, the following table from the report on sewage-disposal by the Committee appointed by the Local Government Board in 1876, gives the cost in different towns by different processes in proportion to the annual rateable value, etc., for the year 1875 : 348 PURIFICATION AND UTILISATION OF SEWAGE. BY IRRIGATION. NAME OF TOWN. Population (about.) Number of Houses. No. of Water- Annual Kateable Per of Eateable Value. Sewage. Scavenging. 1. Banbury . . 12,000 3,485 2,485 34,104 Id. 2. Bedford . . . 18,000 3,500 3,000 65,000 Id. 3. Blackburn . . 90,000 16,700 730 235,127 8d. 8JcL 4. Cheltenham . 45,000 8,725 8,500 217,849 id. id. 5. Chorley . . . 20,000 4,000 200 54,407 4|d. 2jd. 6. Doncaster . 20,000 4,300 68,721 Sid. 7. Harrogate . 12,000 1,500 1,620 50,000 5|d. 8. Leamington . 24,700 4,500 8,370 113,400 5M. Id. 9. Merthyr-Tydfil 55,000 10,778 8,000 135,000 7d. 10. Rugby . . . 8,400 1,700 1,400 45,000 ijd. 11. Tunbridge Wells 23,000 5,750 5,635 142,914 lOd. 12. Warwick . . 11,000 2,400 2,000 43,339 6|d. 13. Wolverhampton 14. West Derby . 71,000 31,400 14,000 750 3,220 210,000 163,000 2d. 4d. lid. lid. BY LAND FILTRATION. 15. Kendal . . . 13,700 2,727 450 44,600 4d. BY PRECIPITATION. 16. Birmingham . 350,000 83,420 8,000 1,229,844 4d. 5fd. 17. Bolton-le-Moors 93,100 18,249 758 311,563 2d. ld. 18. Leeds . . . 285,000 57,000 8,000 945,141 4fd. 4M. 19. Bradford . . 173,723 34,000 4,050 745,671 3d. 2fcL BY THE PAIL SYSTEM. i 20. Halifax . . . 68,000 11,218 2,600 262,581 _ 4d. 21. Rochdale . . 67,000 . 14,388 350 222,000 8|d. PURIFICATION AND UTILISATION OF SEWAGE. 349 SECTION III. TREATMENT OF VILLAGE SLOPS. Some slight reference has already been made to this part of the subject in the previous chapter, but the follow- ing remarks are submitted in the hope that they may prove of further service in assisting to clear up many of the difficulties in which this important question is involved. They are quoted from the pamphlet on Sanitary Defects in Kural Districts, already alluded to, and are an attempt to explain the principles on which my own recommenda- tions have been based, when local circumstances are taken into account : "If the village drains into a large stream which is not used for drinking purposes below the village, and provided there is no nuisance at the outfall, I have not considered it necessary to recommend any interference. If, again, the village drains into an_open ditch without creating nuisance, it will generally be found that a large catch-pit will suffice, provided all excremental filth and slaughter-house refuse are kept out of the drains. But in all cases in which there is nuisance at the outfall, or risk of water pollution used for drinking purposes, I recommend that the sewage, if it be at all possible, should be purified by irrigation or sub-irrigation, and failing these, that it should be filtered through a filter of sufficient size and on the intermittent downward filtration system. In some localities where the soil is porous, and the quantity of sewage comparatively small, a dumb-well in a field will satisfactorily solve the difficulty, or the outfall drain may be carried alongside a field ditch of lower depth, and the soil between will act as a ready filter. Indeed, in purely agricultural districts, the various expedients which might be easily adopted for the purifi- cation and utilisation of village slops are so accessible, so 350 PURIFICATION AND UTILISATION OF SEWAGE. to speak, that in the great majority of instances there not only need be no difficulty in treating them efficiently, but if properly utilised they will pay a fair return to any farmer who is public-spirited enough to take them. As a rule, however, the method of applying them to the soil is anything but satisfactory. Very often the quantity is so small that unless a tank is provided, which can be periodically emptied, the sewage trickles along the surface- gutter in the field, and finally disappears without con- tributing any of its fertilising properties, except it be to the sides of the gutter, on which some rank grass is found growing. But this insufficiency of volume, which con- stitutes the great objection which farmers have to village sewage, can easily be obviated by constructing one of Denton and Field's automatic sewage -meter tanks, in which the sewage can be collected for a period of twelve or twenty-four hours, according to the size of the tank, and by means of a self-acting syphon can be readily discharged when the tank becomes full. If land has to be purchased, half an acre to three quarters of an acre of ground properly drained and laid out would be quite sufficient to purify the slops and refuse-water of a village containing 800 to 1000 inhabitants, provided the sewage is applied on this intermittent system, and the subsoil is porous. Of course, if simple irrigation should be carried out, some three or four acres would be required, but in any case I should recommend the automatic sewage-meter tank to secure rapidity and intermittency of flow. " Sometimes the question is raised as to whether vil- lage slops possess any agricultural value at all. For my own part, I am inclined to believe that they possess fertilising properties quite equal to those of ordinary town sewage ; and, as an instance in point, I may mention that one of the rural sanitary authorities in my district receives a rental of about 6 an acre for a small field laid out in grass, which was purchased for the purification and utilisa- PUBLICATION AND UTILISATION OF SEWAGE. 351 Lion of the slops of an average-sized village. Indeed, any one who takes the trouble to use the household slops in the garden will soon find for himself that the increase in garden produce will more than compensate for the extra trouble. And here I may remark, that part of the objec- tions which farmers generally have to village sewage may be fairly attributed to their not unnatural opposition to any village improvements which are likely to increase the rates, and from which they do not receive any direct benefit. In places where both intermittent downward filtration and simple irrigation are objected to on account of their unsightliness, or the possibility of their giving rise to nuisance, the slops of a small village, if separated from the surface water, could be satisfactorily disposed of by sub-irrigation. In short, the difficulties to be en- countered with regard to village drainage and purification of slops, as I have already said, are not so much engineer- ing difficulties ; the great difficulty in many rural districts is to get anything done at all in this direction. " In sub-irrigation, the drains consist of common agricultural pipes laid at a depth of about 1 2 inches below the surface upon a bed of larger pipes divided longitudi- nally in half, so that the slops soak through between the open joints into the subsoil, part of them filtering into the ground, and part of them being absorbed by the vegetation on the surface. The system may be used in gardens, and is specially applicable to land which is reserved for pasture land. Mr. Field recommends that the drains should be taken up and relaid at least once a year, and it is always advisable to have the subsoil deep- drained. Where the system is adopted, as at Shenfield near Brentwood, for separate houses or groups of houses, care must be taken to avoid pollution of the wells by laying a longer or shorter portion of water-tight drain, according to circumstances, between the flush-tank and the sub -irrigation drains." 352 EFFECTS OF IMPROVED DRAINAGE CHAPTER XIII. xj THE EFFECTS OF IMPROVED DRAINAGE AND SEWERAGE ON PUBLIC HEALTH. THIS subject may be conveniently considered as follows : 1. The effects of dampness of soil on the public health. 2. The sanitary aspects of the water-carriage system of excretal removal. 3. The sanitary aspects of sewage-irrigation. SECTION I. THE EFFECTS OF DAMPNESS OF SOIL ON PUBLIC HEALTH. Amongst the numerous valuable reports which Dr. Buchanan, in his capacity of Health-Inspector, has sub- mitted to the Privy Council, there is perhaps none which excited greater interest at the time than his report " On the Distribution of Phthisis as affected by Dampness of Soil." In a previous investigation regarding the effects of improvements in drainage and water-supply, Dr. Buchanan had ascertained that in certain towns which had been improved in this respect, the mortality from phthisis had greatly diminished; and not only so, but the rate of diminution was found to correspond with the extent of the drying of the subsoil. This result, which was so far unexpected, led to the important inquiry above AXD SEWEKAGE ON PUBLIC HEALTH. 353 mentioned, and the principal facts connected with both may be briefly summarised as follows : In the first inquiry, it was found that wherever the drying of the subsoil had been effected, either by the con- struction of drain-sewers, or by special drains and deep storm-culverts, when the pipe-system was carried out, the mortality from phthisis had decreased from about 50 per cent downwards. In Salisbury, for example, the death- rates from phthisis had fallen 49 per cent; in Ely, 47 ; in Rugby, 43 ; in Banbury, 41 ; and in 13 other towns the rate of diminution, though not so marked, was never- theless noteworthy. On the other hand, it also became apparent that in certain towns, such as Alnwick, Stafford, Morpeth, and Ashley, where no drying of the subsoil had been effected, there was no reduction in the phthisis death- rate, even although the greatest possible progress had been achieved in the removal of filth. This was owing to the fact that in these towns impervious pipe-sewers had been laid down, without making any provision for deep subsoil- draining, the storm-water being carried off in superficial culverts. In some towns, again, such as Penzance, where the subsoil was already dry, the phthisis death-rate re- mained stationary ; and in others, where plans of drainage had been carried out, the sanitary advantages, as regards phthisis, were nullified, because, as in the case of Carlisle, they were so low-lying that the subsoil was at all times more or less waterlogged. So far, therefore, the relation between dampness of soil and phthisis, as one of cause and effect, became highly probable, and Dr. Buchanan's second inquiry converted the probability into a scientific certainty. In this special inquiry (see Tenth Eeport of the Medical Officer of the Privy Council) the various registration districts in the three south-eastern counties of England, beyond the limits of the metropolis, were brought under detailed examination, and. considered in two ways. Firstly, 2 A 354 EFFECTS OF IMPROVED DEAINAGE the true phthisis-rate of the population was ascertained, and due allowance made for the causes of the disease which were likely to influence the rate besides the nature of the soil ; and secondly, the numbers of the population, in each district, that were found "living upon various kinds of soil, and under various topographical conditions," were also noted. The results of these two separate lines of investigation were then brought together, and statistic- ally compared. Without entering into any of the geological details, which are fully given in Dr. Buchanan's report, it may be said, generally, that the dampness or dry ness of a soil depends partly on whether, if pervious, it is retentive of water, or, if impervious, the water can readily drain away. Again, it is obvious that pervious soils may present very different degrees of dryness or wetness, according to the elevation of the ground, and the dip of underlying imper- vious beds. Thus, a stratum of gravel or chalk, covering a sloping bed of impervious clay, is necessarily a dry soil, because the rainfall readily sinks to and flows along the surface of the impervious slope, whereas the same stratum in a valley may be actually waterlogged, although the depth of the stratum may be the same throughout. Bearing in mind, then, the topographical relations as well as the physical qualities of different soils, the following general conclusions, given by Dr. Buchanan as the result of his inquiry, will be at once understood : "(1.) Within the counties of Surrey, Kent, and Sussex, there is, broadly speaking, less phthisis among populations living on pervious soils than among popula- tions living on impervious soils. " (2.) Within the -same counties there is less phthisis among populations living on high -lying pervious soils than among populations living on low-lying pervious soils. " (3.) Within the same counties there is less phthisis AND SEWERAGE ON PUBLIC HEALTH. 355 among populations living on sloping impervious soils than among populations living on flat impervious soils. " (4.) The connection between soil and phthisis has been established in this inquiry " (a) By the existence of general agreement in phthisis- mortality between districts that have common geological and topographical features, of a nature to affect the water- holding quality of the soil ; " (b) By the existence of general disagreement between districts that are differently circumstanced in regard of such features ; and " (c) by the discovery of pretty regular concomitancy in the fluctuation of the two conditions, from much phthisis with much wetness of soil to little phthisis with little wetness of soil. "(5.) The whole of the foregoing conclusions com- bine into one which may now be affirmed generally, and not only of particular districts that wetness of soil is a cause of phthisis to the population living upon it." It is interesting to note that this new discovery in the etiology of disease, which in this country has been associated with Dr. Buchanan's name, had already been brought to the notice of the profession in America by Dr. Bowditch, of Boston, U.S. It would appear, how- ever, that Dr. Bowditch's researches were not known in England until after Dr. Buchanan's inquiry had been finished : and although the priority rests with him, the credit of independently establishing causation of phthisis by dampness of soil as a general law in this country remains with Dr. Buchanan. But it would be unfair not to quote Dr. Bowditch's own remarks. In a very able and lucid address delivered to the Massachusetts Medical Society in 1862, he submitted the two following proposi- tions as containing the essential results of very extended inquiry : 356 EFFECTS OF IMPROVED DRAINAGE " 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, marshes, or springy soils, is one of the principal causes of consump- tion in Massachusetts, probably in New England, and possibly in other portions of the globe. " Second. Consumption can be checked in its career, and possibly, nay probably, prevented in some instances, by attention to this law." But, in addition to phthisis, there are other diseases whose prevalency is largely affected by dampness of soil. Thus, rheumatism, heart-disease, catarrhal complaints, and ague, are especially common in damp districts ; and no greater proof can be given of the sanitary advantages arising from drainage on an extensive scale than the total disappearance of the last-named disease in various parts of the country where it was at one time so common. Moreover, it is evident that in towns situated on damp pervious soils, there is the constant danger of filth-accu- mulations finding their way by soakage into surface-wells, or, as has previously been shown, the soil may eventually become excrement-sodden, so that the air, as well as the well-water, becomes polluted. It is in this sense that the views of Pettenkofer with regard to the spread of cholera and enteric fever become so important, for he insists on humidity of soil as a necessary factor in the etiology of any localised outbreak of either disease. An undrained or damp state of soil, especially in populous places, is thus fully proved to be highly inimical to public health, and, according to Mr. Simon, it answers to the legal definition of the term "nuisance." Sanitary authorities are therefore " bound to provide that such a state shall not continue through want of proper construc- tions for the drainage." AND SEWEKAGE ON PUBLIC HEALTH. 357 SECTION II. SANITARY ASPECTS OF THE WATER- CARRIAGE SYSTEM OF EXCRETAL KEMOVAL. So much has already been said with regard to the evils resulting from collections of excretal matter in towns, that, at first sight, the superiority of any system which prevents these accumulations would appear to be placed beyond dispute. Unfortunately, however, the sewer-system is by no means free from serious dangers, and these have at times been attended with such disas- trous consequences that many have been led to condemn it altogether. But an examination of a few of the more important outbreaks of disease, which have been attributed to the introduction of sewers, will show that such whole- sale condemnation is groundless ; that in fact such out- breaks are due to faults in the system, and not to the system itself. Thus, in the first inquiry of Dr. Buchanan, already alluded to (Ninth Report of the Medical Officer to the Privy Council), it was found that at Chelmsford the death-rate from enteric fever had increased since the in- troduction of the sewer-system 5 per cent, and at Worth- ing it had increased 23 per cent. In both these places, however, there was backing up of the sewage, and, as a consequence, the sewer -gases were forced up into the houses. At Chelmsford, the sewage was received into a tank or underground well ; and, at times, when the pumping -engine was not at work, the well filled, and choking of the outfall-sewer, and flooding of the cellars, ensued. At Worthing, again, although there was not so much backing up of the sewage, there was no provision made for ventilation ; and hence, in the outbreak of 1865, the disease "almost exclusively attacked the well- to-do occupants of houses on the higher levels, where the water-closets were inside the houses, and almost entirely spared the houses, mostly of a much poorer sort, situated 358 EFFECTS OF IMPROVED DRAINAGE on lower levels, where the closet was placed outside the house. It was not so in the times of cesspools ; then these low-lying poor houses were far more attacked with fever than the others." At Morpeth it was also observed that occasional outbreaks of enteric fever had followed times of flood, during which the outfall sewer was under water. Other instances of a similar character might easily be multiplied, but these are sufficient to show that all such outbreaks are due either to faulty construction, deficient ventilation, or imperfect flushing of sewers, or to backing up of sewage in low-lying towns. But while outbreaks of enteric fever do occasionally take place through the agency, of sewers, and amongst others may be mentioned the outbreak at Croydon in 1875, there was no point more clearly established in the whole of Dr. Buchanan's inquiry than -the remarkable reduction of t)ie death-rate from this disease which had taken place in almost all the towns where a proper system of sewerage had been carried out. Thus, in nine of the twenty-five towns examined the diminution in the number of deaths was over 50 per cent, and in ten others from 33 to 50 per cent, the average reduction being about 45 per cent. The same kind of evidence is also afforded in the account of the sanitary condition of Liverpool, given by Dr. Trench in 1868. Dr. Trench wrote : In 1868 "there raged a wide -spread epidemic of typhoid fever in the town, and in the rural districts of the town. . . . While in the families of the rich, in their costly suburban dwell- ings, there was raging a fever, clearly and unmistakably due to the pestiferous emanations from ill-drained cess- pools, or other collections of filth or decomposing organic matter ; the districts in the borough of Liverpool known as the fever districts, and wherein no midden-steads or cesspools were allowed by the Council to remain unaltered, continued, during the whole period of the epidemic, re- markably healthy and free from fever." AND SEWEKAGE ON PUBLIC HEALTH. 359 As regards other diseases, it appears that cholera epidemics had been " rendered practically harmless " in all of the twenty-five towns examined by Dr. Buchanan ; and in the majority of cases the death-rate from diarrhoea had also been considerably reduced. Moreover, the general death-rate was lowered in some towns over 2 per cent ; and the progress made by the inhabitants in cleanliness, decency, and self-respect, was found to be as striking as the improvement in their health measured by the mortuary returns. No doubt, the improved water-supply, which was generally obtained at the same time, aided in the common health - amelioration ; but there can be little question that the system of excretal removal by water- closets and sewers was the real agent at work. But un- less sewers are well ventilated and kept regularly flushed, the best health results cannot be expected. SECTION III. SANITARY ASPECTS OF SEWAGE IRRIGATION. It has already been shown in the previous chapter that irrigation is the only method of sewage-disposal which sufficiently purifies the sewage, and, at the same time, secures, in some instances at least, a profitable agricul- tural return. It now remains to be seen whether the carrying out of the system is attended with danger to public health. And here it may be premised that the same difficulty is encountered in sifting evidence as throughout the whole sewage - question, the difficulty, namely, of dealing with sweeping generalisations which have been based on isolated or exceptional cases. For while, on the one hand, it appears that Dr. Letheby and others have condemned all sewage farms as pestilential swamps, Dr. Carpenter of Croydon and other strenuous 360 EFFECTS OF IMPROVED DRAINAGE advocates of the system, so far from pronouncing them as in any way dangerous to health, maintain that the general health of the neighbouring inhabitants is actually improved by them. But this is pushing the argument perhaps too far on both sides. No doubt some sewage farms answer to Dr. Letheby's description, especially such farms as have been laid out, without any due regard to drainage, in low- lying districts, and those that have been planned on the " catch - water " system. It is evident that this latter system necessitates a swampy condition of both soil and subsoil, unless the ground is porous and well drained, inasmuch as the sewage passes over successive areas of land, overflowing from each into a " catch-water " ditch, which conveys it to the next. Again, when the sewage is not delivered in a fresh state, and at least properly strained, if not disinfected by some precipitation process, offensive emanations are undoubtedly given off, especially when the carriers are not kept clean. But though all this is perfectly true, it is no argument against the system when properly carried out, unless direct evidence can be brought forward to show that, even when the engineering and management are alike satisfactory, there is not only possible but actual risk to health. Such evidence, how- ever, does not appear to be forthcoming ; and even with regard to farms which have neither been planned nor are conducted according to the most approved principles, the evidence as regards the production of disease is of a nega- tive character. Thus, Sir Eobert Christison testified con- cerning the Craigentinny Meadows, near Edinburgh " I am satisfied neither typhus, nor enteric fever, nor dysen- tery, nor cholera, is to be encountered in or around them, whether in epidemic or non-epidemic seasons, more than in any other agricultural district of the neighbourhood " (First Report of the Rivers Pollution Commissioners). At Norwood, again, where the farm lies on a deep clay soil, AND SEWERAGE ON PUBLIC HEALTH. 361 Dr. Cresswell stated that the health of the neighbouring inhabitants was in no way influenced by it ; and according to the Ninth Eeport of the Medical Officer of the Privy Council, the irrigation works at "Worthing did not cause any description of nuisance or injury to health. So far, therefore, the production of disease arising from fsecal pollution of air or water by the system, when properly managed, is not substantiated. But it was feared at one time that entozootic diseases would be greatly propagated, no matter how efficiently the system might be carried out, and Dr. Cobbold's high authority gave currency to the belief. Dr. Cobbold, however, with rare scientific candour, and after careful investigation, has since stated that the fears which he originally entertained have not been real- ised. Animals fed on sewage produce have not been found to be parasitically diseased, nor has any case of parasitism been detected in man which could be traced to the effects of sewage-irrigation. Alarmists, too, have not been wanting, who strenu- ously maintain that the milk of cows fed on sewaged grass is poor in quality, rapidly decomposes, and is unfit to be used. But so far is this from being the case, that there is an overwhelming amount of evidence to the contrary ; and, amongst other instances, I may mention the following : Dr. Brushfield, formerly of Brookwood Asylum, states that he has tried the experiment, and found that cows fed on sewaged grass yield more and richer milk than cows fed on ordinary pasture, and this is also the ex- perience of Mr. Tough, the manager of Lord Warwick's farm. Further, Dr. Hill of Birmingham and Dr. Swete of Worcester, have frequently analysed both milk and butter, and with the most satisfactory results. It need hardly be said that on a well-conducted sewage farm, no sewage is applied for several days before the grass is mown, so that it is always perfectly clean. 362 PREVENTIVE MEASURES DISINFECTION. ^ wf ^ . > ft ^/**^-- VC-U CHAPTEK XIV. PREVENTIVE MEASURES DISINFECTION. THE remarks in this chapter will have reference chiefly to the prevention of infectious diseases, and to the adop- tion of measures best calculated to check their progress when they become epidemic, or threaten to become epidemic, in any locality. By infectious diseases is meant all diseases which are communicable "from one person to another, whether by actual contact or through the agency of certain media, such as air or water. Many of these, however, are comparatively of such little hygienic concern, that they may be excluded from further notice ; as, for example, certain parasitic diseases of the skin, and others, which are never found to affect communities in an epidemic form. The preventive measures, therefore, or other protective means, which will be here considered, apply mainly to the class of diseases termed zymotic, such as smallpox, cholera, typhus fever, enteric fever, scarlet fever, relapsing fever, measles, and the like. Although, in preceding chapters, the mode of propagation of several of these diseases has been considered more or less fully in detail, it will nevertheless be of advantage to allude very briefly to some of the opinions which are entertained concerning their etiology. According to the germ theory of infectious diseases, the origin, de now, of a fever poison is as impossible as the spontaneous generation of plants or animals; the inference being that enteric fever, for PKEVENTIVE MEASURES DISINFECTION. 363 example, can only be developed from the specific con- tagium of the fever, just as a case of smallpox cannot occur without infection from some pre-existing case. Now, to this it may be replied that the poisons of all the acute specific diseases must have originated at one time or another independently of pre-existing cases, and there is no reason to believe, therefore, that the causes which led to the development of the first cases should not be in operation at the present day. As regards the various views which are at present entertained with respect to the nature oT contagia little need be said, because so much is still left open to controversy. Some maintain that the particles are of animal origin, born in, and only growing in, the body ; in other words, that they are minute portions of bioplasm endowed with a certain amount of independent life, which enables them to thrive on suitable pabulum. This view has been ably advocated by Dr. Beale, and has been modified by Dr. Eichardson under the name of the glandular origin of disease. Others, such as Hallier, maintain that the par- ticles are of fungoid nature, and simply grow in the body after having been introduced from without ; while some of the most careful observers hold that they are of the nature of the Schizomycetes, such as Bacteria, Microzymes, Bacilli, Vibrios, Monads, etc. No doubt these minute organisms are intimately associated with some of the so- called specific diseases, and the researches of Pasteur on fowl-cholera and charbon go to prove that these two diseases are not only due to Bacteria, but that they can in all probability be prevented or modified by cultivated virus. The inquiries into the wool -sorters' disease at Bradford afford further evidence that it is identical with the anthrax of cattle, in which the Bacillus anthracis plays such a prominent part, while Bacilli were found to be the diagnostic agents in the poisoning by hams at 364 PREVENTIVE MEASURES DISINFECTION. Welbeck (see Chapter IL) Koch's researches into the nature of phthisis have also associated the disease with the presence of well-defined Bacilli. But the very uni- versality of these various micro-organisms affords the strongest argument against the view that they constitute the contagia of any of the specific diseases, and there are good grounds for believing that further pathological research will demonstrate their presence in the blood of patients who have died from other diseases. The fact is, as Dr. Murchison has pointed out, the question at issue has been discussed on too narrow a basis, and the possibility of the several zymotic diseases differ- ing greatly has been too much lost sight of. Just because all of them are infectious, it has been argued that none of them can be generated except by a specific contagium. But even as regards this infectious quality, there is the widest possible divergence between them ; for while, on the one hand, we find that smallpox and scarlet fever are extremely infectious, we find, on the other, that enteric fever and erysipelas have only a limited power of pro- pagating themselves, except under insanitary conditions which are favourable to their development and spread. Moreover, while, in regard to smallpox, it can never at the present day be traced to any other cause than infec- tion, in diphtheria it is comparatively rarely that the first case, even of several, can be traced back to any pre- existing case ; and the same remark applies generally to sporadic cases or limited outbreaks of enteric fever as they occur in rural and small urban districts. Then, again, it is a matter of almost daily observation that pyaemia and puerperal fever are not only generated de now, but the researches, more especially of Dr. Sanderson, show that they can be generated at will, and when so generated they become, under certain circumstances, eminently infectious. It is no argument, therefore, that because a disease is PREVENTIVE MEASURES DISINFECTION. 365 infectious it cannot be generated de now, and the argu- ment becomes weaker still when it is remembered that several of these diseases do not breed true, nor do they run a definite course. Thus we find erysipelas and pyaemia running into each other, and that either of these, or scarlet fever in its varied forms, may generate puerperal fever in the parturient woman. Without, however, entering further into the speculative or scientific aspects of this question, I prefer quoting the matured views of Mr. Simon. After dilating upon the influence which filth, and more especi- ally excremental filth, exercises in the development and spread of diseases such as cholera and enteric fever, which, in respect of their leading symptom, may be generalised as diarrhoeal, Mr. Simon continues " But though hitherto, for convenience of argument, I have referred specially to the influence of human ex- crement in determining the spread of ' specific ' infections from man to man, and provisionally as if man's body were the sole birthplace of the several contagia which afflict his kind, assuredly that intermediary influence is but part, and it may be but a very subordinate part, of the faculty by which filth produces disease. While it is indeed true, as regards some contagia, that at present we know them only as incidents of the human body, wherein we see them in case after case multiplying their respec- tive types with a successivity as definite and identical as that of the highest orders of animal or vegetable life, and while thus it is at present true, for instance, of small- pox or syphilis, that a case arising independently of a previous like case is hitherto practically as unknown to us as the parentless production of dog or cat, our know- ledge with regard to other very important contagia is growing to be of larger scope. I would mention it as among the most hopeful advances of modern preventive medicine, that some diseases, which, in the sense of being 366 PREVENTIVE MEASURES DISINFECTION. able to continue their species from man to man, are apparently as ' specific ' as those which I have above named, seem now beginning to confess in detail a birth- place exterior to man, a birthplace amid controllable conditions in the physical nature which is around us, a birthplace amid the ' common,' putrefactive changes of dead organic matter. Eeferring again now to what I have not pretended to be able to analyse in detail the excess of miscellaneous, and in great part nominally ' common/ disease in filthy neighbourhoods, I would particularly wish to connect with that subject a reference to our growing scientific knowledge in the matter of the ' common ' septic ferment. The pathological studies of late years, including eminently certain very instructive researches which Pro- fessor Sanderson has conducted under my Lords of the Council, have clearly shown that in the ' common ' septic ferment, or in some ferment or ferments not hitherto to be separated from it, there reside powers of disease- production as positive, though not hitherto as exactly defined, as those which reside in the variolous and syphi- litic contagia. Experimentally we know of this ferment, that, when it is enabled by artificial inoculations to act in its most effective way on the animal body, and even more when it has received a curious increment of strength which its first propagation within the living body seems to bestow on it, it shows itself one of the most tremendous of zymotic poisons. It rapidly in the one animal body de- velops disease, which then is communicable to another : febrile disease, with inflammations numerous and intense, and including in marked degree one of the acutest known forms of intestinal inflammation and flux : disease exactly corresponding to certain very fatal and unfortunately not unfrequent infections to which lying-in women, and per- sons with accidental wounds and the wounds of surgical operations, are most subject, but which also sometimes PREVENTIVE MEASURES DISINFECTION. 367 occur independently of such exceptional states ; infections, chiefly known under the names of erysipelas, pyaemia, septicaemia and puerperal fever ; infections which we sometimes see locally arising anew in unquestionable dependence on filth, but of some of which, when arisen, it is perfectly well known that they are among the most communicable of diseases. And a further, perhaps still more instructive, teaching of the artificial infections is this : that the ' common ' ferment, which in its stronger actions quickly destroys life by septicaemia, can in slighter actions start in the infected body chronic processes which will eventuate in general tubercular disease. I need hardly point out that the above facts, extremely suggestive though they are, must of. course, in relation to my main argument, be applied only under certain reserve ; that evidently the exact conditions of the physiological experi- ment are not reproduced in ordinary life ; and that against the common septic ferment, as presented in fouled atmo- sphere or fouled drinking water, the living human body in its normal state can apparently make considerable (though presumably not unlimited) resistance. But after all such reserves the truth remains, that, looking well at the pathology of human life under residence in foul air, we find ourselves again and again reminded of these results of physiological experiment; often seeing phthisis and other tubercular and like diseases gradually developed, as though under gradual overpowering of the limited normal resistance to the septic ferment ; or seeing and particu- larly where some exceptional bodily state (wounded or puerperal) gives opportunity the sudden invasion of erysipelas or other septic infection, not in discoverable dependence on any human infectant, but conceivably a filth-inoculation from the air. The line of reflection thus suggested is one which I cannot now follow further, but of which the practical interest seems to be extremely 368 PREVENTIVE MEASURES DISINFECTION. great. For, while the excessive production of fatal disease in filthy neighbourhoods is a fact as to which there can be no doubt, and of which the immediate significance is deplorable, the ulterior suggestion is this : that so far as filth in any instance produces anew such a disease as erysipelas or puerperal fever on the one hand, or phthisis or other tubercular disease on the other, the mischief first done is of a sort which entails certain possibilities of extension : such, namely, that in the one instance by accidental contagion, as in the other instance by heredi- tary transmission, it may, for aught we know, indefinitely extend beyond the sphere in which filth first produced it." (See Mr. Simon's Reports, New Series, No. II.) But apart from the influence of sanitary defects in the development and spread of infectious diseases/ and apart also from the influence of personal susceptibility, which as regards some of them is very great, there are certain other influences obscurely called epidemic, which appear to act as predisposing causes, or, at all events, to give increased energy to causes already in operation. Such epidemic influence, however, is merely the expres- sion of the fact that we cannot always explain why it is that certain diseases should rage with terrible violence in a particular locality at one time and not at another ; or why the type of the disease should now be mild and now severe ; or why again, a disease, such as cholera, should be subject to periods of pandemic extension. All these are questions which still afford ample room for speculation and research. Meanwhile it is encouraging to sanitary efforts to find that as civilisation advances, epidemics de- crease in frequency and intensity, and that nothing tends so much to weaken their power and circumscribe their range of action, as a free circulation of pure air in in- habited places, a good supply of pure water, and a suffi- ciency of wholesome food. PREVENTIVE MEASURES DISINFECTION. 369 In preceding chapters the mode of propagation of several of these diseases has been considered more or less fully in detail. It has been shown, for example, that there is good reason to believe that the contagia of cholera and enteric fever are contained in the alvine discharges, which, in their turn, pollute the water-supply or the respired air ; that typhus fever is essentially a disease of overcrowding ; and that relapsing fever is associated with wide-spread insufficiency of food. It has also been shown that, when the local circumstances which are found to favour the propagation of any one or other of these dis- eases in an epidemic form are improved, the extension of the disease is checked, and its ultimate extinction from a portion of the community secured. Improvement of local circumstances is, therefore, a most important, and perhaps the most important, part of prevention. But there are other measures which are found to be of immense service in checking the course of any epidemic, such as the isolation of the sick, the use of disinfectants, and the destruction of the contagia by any other means which may be deemed most efficacious. In order, however, to be able to apply these measures judiciously, some know- ledge of the mode of propagation of the several epidemic diseases is essential, and this part of the subject may be briefly discussed as follows : SECTION I. MODE OF PROPAGATION OF EPIDEMIC DIS- EASES, AND THE PRECAUTIONARY MEASURES INDI- CATED. 1. Cholera. The basis of precautionary measures with regard to this disease is thus described by Mr. Simon : " That, when cholera is epidemic in any place, persons who are suffering from the epidemic influence, 2 B 370 PEEVENTIVE MEASURES DISINFECTION. though perhaps with only the slightest degree of diar- rhcea, may, if they migrate, be the means of conveying to other places an infection of indefinite severity; that the quality of infectiveness belongs particularly, if not exclusively, to the matters which the patient discharges, by purging and vomiting, from his intestinal canal ; that the matters are comparatively non-infective at the moment when they are discharged, but subsequently, while under- going decomposition, acquire their maximum of infective power; that choleraic discharges, if cast away. without previous disinfection, impart their own infective quality to the excremental matters with which they mingle, in drains or cesspools, or wherever else they flow or soak, and to the effluvia which those matters evolve; that if the cholera-contagium, by leakage or soakage from drains or cesspools, or otherwise, gets access, even in small quantity, to wells or other sources of drinking-water, it infects, in the most dangerous manner, very large volumes of the fluid; that in the above-described ways even a single patient with slight choleraic diarrhoea may exert a powerful infective influence on masses of population among whom perhaps his presence is unsuspected ; that things, such as bedding and clothing, which have been imbued with choleraic discharges, and not afterwards fully disin- fected, may long retain their infectious properties, and be the means of exciting choleraic outbreaks wherever they are sent for washing or other purposes." (Eighth Report of the Medical Officer of the Privy Council) The practical applications of the above remarks are therefore these, that the alvine discharges and vomited matters, as well as any clothing or bedding tainted by them, should be carefully disinfected ; and that, if this is carefully attended to, there is little or no risk of infection by direct contact with the patient. It would be out of place here to refer, except in the PREVENTIVE MEASURES DISINFECTION. 371 briefest terms, to the various conflicting doctrines which have been advanced with regard to the propagation of this disease. Suffice it to say, that while Mr. Simon's views are in full accordance with the experience of those who have most carefully investigated its etiology in this country, the views more especially of Dr. Cunningham, the Sanitary Commissioner of the Government of India, are so entirely opposed to them, that it would appear as if the results of all the inquiries which have been so carefully made are absolutely worthless, and that previous inves- tigators have been on the wrong track. In the Ninth Annual Sanitary Eeport to the Indian Government, he declares in effect, on the evidence of 108 outbreaks, that the transportability of cholera by persons is erroneous, that the water-spread theory of the disease is untenable, and that the influence of tainted air cannot be at present affirmed. According to him, so little is known about the epidemic extension of the disease, that preventive measures are practically of little or no value. It is satis- factory to note, however, that even in India, these views are already beginning to receive substantial refutation; for in his report for the second quarter of 18*76, Dr. Payne, the medical officer of health for Calcutta, shows clearly that though other insanitary conditions in the native parts of the city remain unaltered, the introduction of a public water-supply, which took place in 1870, has been followed by a remarkable and continuous diminution in the spread of cholera. Pettenkofer's views have already been alluded to in Chapters VIII. and XIII. ; and those who are desirous of studying the European relations of the disease, should read the elaborate report of Mr. Netten Eadcliffe, and the abstract by Dr. Seaton of the proceedings of the International Congress held at Vienna in 1874, both of which are contained in No. V. of ^ the New Series of Mr. Simon's Reports. 372 PREVENTIVE MEASURES DISINFECTION. 2. Enteric or Typhoid Fever. That this disease is essentially a filth-disease is alike admitted by those who accept the doctrine of Von Gietl and Dr. Budd, and those who, like Dr. Murchison and Sir William Jenner, maintain that it may be generated independently of previous cases. As it occurs in rural and small urban districts, my own experience leads me to believe that the great majority of scattered cases, and many of the first cases of isolated outbreaks, are due to poisoning of air, drinking-water, or other ingesta, with decomposing filth. Most frequently it is found that the well-water has become polluted by soak- age from some drain, cesspit, or manure heap, and in some instances in would appear as if ill-defined forms of enteric fever, such as those vaguely termed low fever, gastric fever, febricula, and the like, may be caused by decom- posing organic matter not necessarily faecal. But whether the disease is produced by befouled air or polluted water, there is a constantly accumulating amount of evidence which goes to prove that neither the air nor the water need be tainted with the specific contagium of the disease. At the same time, there is no fact more clearly established in preventive medicine than this, that whenever the disease is developed, the bowel discharges possess an in- fective power, which, where local conditions assist, can operate with terrible force, and often at long distances from the sick. Indeed, exclusive of the epidemic influ- ence, what has been said with regard to the infective power and the mode of propagation of cholera applies to enteric fever, and, in the main, the same precautionary measures (see Appendix) are indicated. The evacuations, and any clothing tainted with them, should be thoroughly disinfected. The water-supply should be examined, and in localities where the sewer-system has been introduced, the condition of the water-closets and drains, with regard to ventilation, flushing, and trapping, should be carefully PREVENTIVE MEASURES DISINFECTION. 3*73 inquired into. Any epidemic of enteric fever in a sewered town points to imperfect ventilation, deficient flushing, or to some faulty construction of the sewers or drains, or to contamination of the water-supply, as in the outbreaks of Sherbourne, Over Darwen, and Lewes (see Chap. VIII.) ; or to polluted milk, as in the outbreaks in Marylebone, East Moseley, and Eagley (see Chap. II.) In villages and country districts it points to polluted wells, bad drainage, or filthy privies, all of which may originate the disease in the first instance as well as be the means of propagating the specific contagium when it is developed or introduced. If proper precautions are taken there is little or no risk that the disease will spread to persons who nurse or otherwise closely attend upon the sick. 3. Typhus Fever. The conditions essential to the propagation of typhus fever are mainly these :- Over- crowding and deficient ventilation ; clothing saturated with cutaneous exhalations; squalor and want; a deteri- orated state of the constitution from whatever causes; and a moderate temperature. 'Si\&? ^ u^ ^*2T7 The disease, once generated, is highly contagious, the contagium being thrown off by the cutaneous and respi- ratory exhalations. The air of the sick-room is therefore contaminated, and by this means the contagium may attach itself to the walls of the room, or to furniture, or to bedding and clothing, and may long retain its efficacy if fresh air is excluded. Cases are not at all uncommon in which the disease has been communicated to persons who have been employed in cleaning out places which had been occupied by the sick, even though some con- siderable time had elapsed after the sick had been re- moved. But the contagium does not travel far through the air, for, according to Dr. Murchison's observations, it 374 PREVENTIVE MEASURES DISINFECTION. appears that if a patient is placed in a well-ventilated room, the attendants incur little risk, and the other occupants of the house none whatever. Dr. Eussell, medical officer of health for the City of Glasgow, has also reported to the same effect, and has, in addition, deduced from his experience other points of practical importance. Thus, in his report on the Fever Hospital for 1870, he writes : " All these facts concur in proving (1) that, where attention is paid to personal and general cleanli- ness, typhus does not carry far, so to speak, through the atmosphere, and is not portable; (2) close approach to, and contact with, the infected individual and his dirty belongings, lead with great certainty, even in the best sanitary circumstances, and in healthy and well-fed people, to an attack at the end of about four weeks in the great majority of cases, but not in a few until the lapse of some months; (3) that individual susceptibility does not exist, except that which is conferred by a pre- vious attack." As regards the period of the disease at which the contagium is most powerful, there is a difference of opinion. According to Dr. Murchison the disease is most readily propagated from the end of the first week up to convalescence that is, during the period when the peculiar typhus smell from the skin and lungs is the strongest. The practical deductions from these observations are as follows : The sick should be isolated as much as possible; the attendants, by preference, should be those who have been protected by a previous attack ; others who visit the sick should avoid coming into close contact with them ; the room should be well ventilated by open windows and fires if necessary ; all extraneous furniture, such as carpets and curtains, should be removed and disinfected ; disinfectants should be constantly used in PREVENTIVE MEASURES DISINFECTION. 375 the room ; the bedding and clothing should be disinfected or destroyed; and after convalescence the whole room, and every piece of furniture, should be purified. 4. Relapsing Fever. Excluding for the present the consideration of the public measures which should be adopted when an epidemic of relapsing fever is raging, the hygiene of the sick-room should be conducted in the same manner as in the case of typhus fever. The disease, however, is much less frequent than typhus, and though contagious in the same way, is not contagious to the same extent. It selects its victims from the poor and ill-fed, who live in crowded, un ventilated buildings, rather than from the well-nourished, whose surroundings are healthy. 5. Smallpox. " There is no contagion," wrote the late Sir Thomas Watson, " so strong and sure as that of small- pox ; none that operates at so great distance." The contagium, indeed, may be wafted from house to house on opposite sides of a street ; and, as recent inquiries have shown, it may be conveyed by the air to houses in the neighbourhood of smallpox hospitals. The poisonous material is thrown off from the cutaneous and mucous surfaces of the patient, and is contained in the exhalations, the excretions, the secretions, the matters in the vesicles and pustules, and in the scabs. It contaminates the air of the sick-room, and attaches itself, as in typhus, to everything contained in the room, or which comes in con- tact with the patient. Further, it is possessed of great vitality, and if protected from air may remain active for an unknown number of years. The period of incubation varies from ten to sixteen days, though in the majority of cases it does not exceed fourteen. The patient ought not to be pronounced free from infection until all the pustular crusts have fallen off, and the whole surface of the body has been well sponged with water and some disinfectant soap, or several warm baths have been taken. 3*76 PREVENTIVE MEASURES DISINFECTION. Unfortunately, as regards the speedy suppression of outbreaks of this disease, it not unfrequently happens that the first few cases, if of a modified nature, are not cor- rectly diagnosed, the disease "being mistaken for chicken- pox or measles. In my own district I have had to report several outbreaks in which mistakes of this description have been made, and I have also been consulted in a few cases when the disease turned out not to be smallpox, as suspected, but either measles or chicken-pox. Of course it is often very difficvilt to diagnose with certainty an isolated case of either of these diseases, and hence it is very essential that not only should the character of the eruption be carefully scrutinised, but the premonitory and other symptoms, as well as the probable source of infec- tion, should also be carefully inquired into. It need hardly be said, too, that until the nature of the disease is clearly ascertained, every precaution should be taken as regards isolation and other preventive measures. Con- cerning the protection afforded by vaccination and re- vaccination, as well as other rules of prevention, see Appendix. The stage of the disease at which the poison is first generated in the person of the sick is not accurately de- termined, but there cannot be the slightest doubt that, so soon as a case is diagnosed, precautionary measures should forthwith be adopted. If the patient is not at once re- moved to a hospital, he should be carefully isolated ; those in attendance on him should if possible be protected by a previous attack of smallpox or by re- vaccination ; and the same details with regard to the hygiene of the sick-room, disinfection, etc., should be observed, as have already been insisted on in cases of typhus. All persons living in the same house or adjoining houses over twelve years of age, should at once be re- vaccinated, and all children whose vaccination marks are not large and distinct. PREVENTIVE MEASURES DISINFECTION. 3*77 6. Scarlet Fever. Although this disease may attack persons of all ages, it specially attacks children between the third and fourth year ; after the fifth year the chances of attack decline rapidly. The contagium, like that of smallpox, is exceedingly powerful and volatile, so that no susceptible person can remain in the same room for any length of time, or even in the same house, unless the patient is carefully isolated, without running great risk of contracting the disease. Moreover, the contagium is con- tained in everything which proceeds from the patient, but more especially in the cuticular scales given off in de- squamation. These scales, laden with the specific poison, are conveyed by the currents of air to every part of the room, and may settle on clothing, bedding, furniture, walls, etc. They preserve their virulence for an unknown period of time, and when disturbed are always liable to reproduce the disease. Thus, there are several instances recorded in which the fever has been contracted by sleep- ing in a room, which weeks previously had been occupied by a scarlet fever patient ; and the fact that the poison adheres to articles of clothing is proved by instances in which the disease has been propagated by the clothing of pupils returning home from school. The cases already referred to in the chapter on water impurities are also of great interest in showing the absolute necessity of the utmost care and cleanliness to be observed on all occa- sions, whether the attack is mild or severe. In the vast majority of cases a previous attack confers permanent immunity from the disease. There is reason to believe that the disease is infectious even before the eruption appears, but, according to my own experience, it is seldom that other cases break out in the same family if the first case is promptly removed to a hospital, and proper steps are taken to disinfect the house, etc. The patient ought not to be pronounced free from 378 PEEVENTIVE MEASURES DISINFECTION. infection until desquamation has ceased, and the surface of the body has been well bathed. The precautionary measures which are indicated by the above remarks are obvious ; although it may be ad- mitted that it is impossible to carry them out efficiently in the crowded homes of the poorer classes. But even in homes where no difficulty should be experienced, the necessary isolation and disinfection are too often grossly neglected, either because they are irksome, or, if the case is slight, because they are considered to be needless. With regard to special precautions, see Appendix. 7. Measles. This disease, like scarlet fever, is emi- nently communicable. The contagium may be conveyed by fomites, or by means of the contaminated air of the sick-room. The disease attacks persons of all ages and of both sexes, but is much more frequent amongst children. The risk of infecting commences with the primary fever, and is greatest when the specific eruption is fully deve- loped. As a rule, a patient who has once suffered from the disease is no longer liable to a second attack. 8. Whooping-Cough. The susceptibility to this dis- ease is so strong that few persons have passed the age of childhood without having contracted it. Moreover, the infecting distance of the contagium appears to be very considerable, inasmuch as domestic isolation is frequently found to be of little avail in preventing the disease from attacking other members of the family who have not been protected by a previous illness. That the contagium may likewise adhere to clothing, and may in this way propa- gate the disease, has been clearly proved by numerous instances. Such being the mode of propagation of measles antl whooping-cough, the precautionary measures which are indicated comprise isolation of the patient, if other members of the family have not been protected by a pre- PKEVENTIVE MEASURES DISINFECTION. 379 vious attack; careful attention to the hygiene of the sick-room, and disinfection of the clothing, bedding, etc. And here it may be pointed out that the prevalence of these two diseases is in great measure attributable to the culpable neglect, arising from the popular belief, amount- ing almost to fatalism, that children must contract them some time, and that there is therefore little use in endea- vouring to take any protective steps when either disease is epidemic. The consequence is that the epidemic con- tinues to spread so long as susceptible victims are to be found in the community, and only dies out for a time when almost all these have been attacked. How far the medical profession are to blame in allowing this popular delusion to retain its hold on the public mind it would be difficult to say, but until they unite in striving to get rid of the listless apathy which it engenders, the preva- lence of such epidemic diseases will continue to be an opprobrium to sanitary science. Nor must it be forgotten that medical men, in the hurry of practice, do sometimes, though unwittingly, convey the contagium of an infectious disease from one patient to another. For example, in- stances are not at all uncommon in which scarlet fever has been propagated in this way, and the records of puerperal fever contain the histories of many painful cases which could never have occurred had greater care been taken to guard against such fatal mishaps. 9. Diphtheria. Although the etiology of this disease still continues to afford ample scope for research, there can be no doubt that, in its origin and spread, it is inti- mately associated with sanitary defects. In the majority of the sporadic cases which have come under my own notice, I have every reason to believe that the disease was attributable to polluted drinking-water, though in a few others there could be as little doubt that foul effluvia from cesspools, drains, and the like, produced the malady. 380 PREVENTIVE MEASURES DISINFECTION. According to Dr. Thursfield, medical officer of health of the Shropshire Combined District, it is associated with dampness of dwellings, and in this respect may, like ague, be largely preventible by the improvement of local condi- tions. In most cases the severity of the disease is directly influenced by the conditions under which the person attacked is living ; and the symptoms become greatly intensified by the disease passing through a person who has newly come into the locality. Diphtheria is more prevalent in rural than in urban districts, and although it may attack adults, it is, like scarlatina, a disease of child- hood and early youth. When once the disease becomes developed it is eminently infectious, the contagium being given off principally from the throat and breath, although there can be little doubt that it is also conveyed by the other excretions, and may thus become disseminated through the agency of sewers or closets. In a household, and among children, it is often disseminated by kissing, and, indeed, the greatest care ought always to be taken not to bend over the patient so as to inhale the breath. Further, there can be no doubt that the infection is most portable, and may be conveyed in articles of clothing and the like, but the opinion that it may be wafted long dis- tances in the air does not appear to be well corroborated. As in enteric fever, the disease may be spread through the agency of contaminated milk ; and, according to Dr. Thursfield, the infection can be taken from a corpse, or, at least, from its adjuncta. Of all diseases, not even excepting scarlatina, this is the one most liable to be disseminated through the agency of schools, partly because the symptoms are frequently so mild as not to prevent children from attending school, but chiefly because the disease is peculiarly liable to be spread by the breath, and may be disseminated by the throat after children are sent back to school apparently well. There can be no PEEVENTIVE MEASURES DISINFECTION. 381 doubt that the agency of schools in the spread of children's diseases, such as scarlatina, diphtheria, and measles, is becoming all the more potent as attendance becomes better enforced; but now that Sanitary Authorities are empowered to close schools to prevent the further spread of infectious disease, the dangers should become greatly lessened. The precautions to be taken in respect to diphtheria are much the same as those which are recommended with regard to scarlatina. (See Ap- pendix.) 10. Diarrhoea. Although many are inclined to dis- pute the grounds on which diarrhoea is classed as a zymotic disease, there is abundant evidence to prove that wherever it becomes prevalent it is due in large measure to insanitary conditions, and that so-called summer diar- rhoea is often as distinctly infectious as enteric fever. No doubt there is a considerable amount of diarrhoea, especially that known as infantile diarrhoea, which is due to hand-feeding and other errors in diet; but according to Dr. Johnson of Leicester, who has written a very exhaustive paper on the subject (see Sanitartf Record, August 15, 1879), out of the 238 deaths which he in- vestigated, as many as 165, or 69*3 per cent of the cases were breast-fed. As is well known, diarrhoea has been exceptionally prevalent in recent years in Leicester, more particularly during the summer and autumn months, and Dr. Johnson was requested by the Sanitary Committee to investigate the causes of the origin and spread of the disease. Dr. Johnson, in his painstaking researches, ascertained that the disease was not limited to the infan- tile portion of the community, nor was it confined to the most unhealthy parts of the town. He found, however, that after a period of warm and dry weather, the appear- ance of diarrhoea is hastened ; and he attributes the origin and spread of the disease to the presence of bacteria in 382 PREVENTIVE MEASURES DISINFECTION. sewer-air, and the foul effluvia which emanate from cess- pools, middens, and other filthy accumulations, and which find a ready entrance into the air of houses. These bacteria were found in the stale food of infants and in the juices of stale or over-ripe fruit, and they were also detected in the bowel-discharges of patients affected with the disease. He therefore concludes that badly- ventilated and stagnant sewers constitute an important factor in the causation of the disease, and that different conditions of drainage account largely for the varying prevalence of diarrhoea in different towns. In these remarks on the mode of propagation of in- fectious disease, it has been assumed throughout that the body of the diseased person is the soil in which the germs or infective particles of the disease are multiplied ; that these germs, whatever be their nature, are given off by the patient, and may contaminate the air, drinking-water, or other ingesta, or may adhere to clothing, bedding, fur- niture, or walls of a room ; that, either directly or after remaining dormant for an unknown period of time, they may infect other persons ; and that, by adopting suitable measures they can be destroyed altogether, or rendered inoperative to a large extent. So far also these remarks have had special reference to the precautionary measures which form a part of personal and domestic hygiene, and which fall under the control and regulation of the private medical attendant. The general proceedings, which should be carried out under the advice of a health officer in places attacked or threatened by epidemic disease, are set forth in an official memorandum given in the Appendix. SECTION II. DISINFECTANTS. In the wide sense of the word, the term disinfectant may be defined as any agent which oxidises or renders PREVENTIVE MEASURES DISINFECTION. 383 innocuous decomposing organic matters and offensive gases, which arrests decomposition, or which prevents the spread of infectious diseases by destroying their specific contagia. The term, therefore, includes any agent which possesses deodorising, antiseptic, or fixative properties. Without entering into any discussion on the modus operandi of disinfectants generally (because the subject is still under dispute), it will be convenient for practical purposes to enumerate and describe the most useful amongst them seriatim, and without any attempt at classification. 1. Heat and Cold. While extreme cold prevents putrefactive change, and therefore acts as an antiseptic, extreme heat is destructive of all organic matter, and in this respect it is the most efficacious, as it is the most ancient, of all disinfectants. But even a temperature much below that of actual combustion is found to be sufficiently powerful, if continued for any length of time, to kill animal or vegetable germs, and to render inert any contagious matter. Thus, the late Dr. Henry proved experimentally that the vaccine virus was deprived of the power of reproduction when exposed for three hours to a temperature of 140 Fahr., while a temperature of 120 failed to produce this effect. As a result of these and other experiments, he was the first to recommend the employment of the hot-air chamber to disinfect clothing, bedding, and the like; and experience has proved that, when conducted with care, the plan is highly successful. Among disinfecting stoves which have been found to work satisfactorily may be mentioned Dr. Ransome's self-regu- lating disinfecting stove, manufactured by Goddard and Massey, Nottingham ; the patent disinfecting stove, manu- factured by Bradford and Co., Crescent Iron Works, Sal- ford; and Dr. Scott's disinfecting chamber. 2. Charcoal, and specially animal charcoal, is a power- f 384 PREVENTIVE MEASURES DISINFECTION. V/J ful deodorant, but there is no evidence to show that it 1 6 has any effect in destroying specific disease-germs. It oxidises offensive organic effluvia, and is therefore very useful in purifying sewer -gases or other filth emana- tions. 3. Chlorine decomposes sulphuretted hydrogen and " ammonium sulphide more certainly than any other gas, and is an energetic destroyer of all organic substances prone to decay. It is especially valuable in purifying rooms which have been occupied by persons suffering from infectious diseases, but it is doubtful whether it can be of much service in the hygiene of the sick-room itself, because, even when largely diluted, it is very irritating to the lungs. It is given off in small quantities by chloride of lime moistened with water, or when employed in scrubbing out the floor. It may also be obtained by adding a little muriatic acid gradually to a wine-glassful of Condy's fluid, or to crystals of potassium chlorate. When required in large quantity for the disinfection of empty rooms, it is most rapidly obtained in one of the following ways : (1.) To equal parts of common salt and binoxide of manganese add two parts of water, and about the same amount of strong sulphuric acid. (2.) To one part of powdered binoxide of manganese add four parts by weight of strong muriatic acid. (3.) To three parts of bleaching powder add one part of strong sulphuric acid. In any case, the quantities required will depend upon the size of the room. 4. Nitrous Add. Nitrous fumes are obtained by adding strong nitric acid, diluted with a little water, to copper filings. The power of oxidation of organic matter possessed by nitrous acid is very great, and no disinfectant will more readily remove the offensive smell of the dead- house. The fumes, however, are exceedingly irritating and dangerous, so much so, that" this process of disin- PREVENTIVE MEASURES DISINFECTION. 385 fection is only suitable for empty rooms, and under skilled superintendence. 5. Iodine, though less useful than chlorine, has been recommended as a substitute by Dr. Eichardson and others. It is a powerful antiseptic, and may be diffused through the air of a room by placing a small quantity of the substance on a warm plate, but it is not suited for the sick-room. 6. Bromine. The vapour of bromine can be obtained by exposing a solution of bromine in potassium bromide in open dishes. It was largely used as an atmospheric disinfectant during the American War, but has not found much favour in this country. 7. Sulphur Dioxide or Sulphurous Acid Gas. This is exceedingly useful for disinfecting empty rooms. It is obtained by burning sulphur in an earthenware pipkin or other vessel that will not readily crack. It decomposes sulphuretted hydrogen, and as it combines with ammonia, it deodorises or destroys stinking alkaloids, and, probably, disease-germs. Usually fumigation is best effected by burning about 1 Ib. of lumps of sulphur for every thousand cubic feet of space in an iron dish (or the lid of an iron saucepan) supported on a pair of tongs over a bucket of water. In a long room it is advisable to burn the sul- phur in one or two places in order to secure thorough disinfection. 8. Carbolic Acid. This is one of the most popular disinfectants, and is especially valuable on account of its highly antiseptic properties. In its pure state it is a white crystalline solid, which in a diluted form has been found to be of immense service in preventing putrefactive change in surgical wounds. The commercial article is a thin, tarry fluid, possessing a somewhat offensive odour. It is highly poisonous, and has already been productive of several fatal accidents, on account of its having been 2 c 386 PREVENTIVE MEASURES DISINFECTION. mistaken for porter or other fluids. For this reason the carbolic acid powder is safer as a domestic disinfectant. It can be employed in scrubbing out floors, in steeping infected clothing, and in vessels for receiving the excreta. It is also very useful in disinfecting urinals, latrines, water-closets, stables, midden-heaps, etc. In whatever form, the acid is destructive of the low forms of animal and vegetable life, and arrests or prevents all kinds of putrefactive change. It should never be sprinkled freely about the sick-room, on account of its irritating and dis- agreeable odour. 9. Terebene. This disinfectant, which has been de- signed by Dr. Bond of Gloucester, is obtained from spirits of turpentine. It has a fragrant odour, very much re- sembling that of pinewood, and is powerfully antiseptic. It has been used by Professor Maclean at the Koyal Victoria Hospital, Netley, with excellent effects, in cor- recting the highly offensive evacuations of dysentery, and the fcetor of purulent collections, such as occur in cases of liver abscess and empyema, while, at the same time, it was found to sweeten the air of the wards by diffusing through them its own peculiar pine-like fragrance. It is especially suited as a deodorant for commodes, and as a disinfectant for the bowel-discharges of infectious diseases. It is only slightly soluble in water, but it mixes readily with sweet oil or with benzoline for use in surgical dress- ings. The experience of its effects gained at Netley shows that it is peculiarly suitable for use in Indian hospitals and in hospitals generally, and it specially commends itself for use in the sick-room. 10. Oupralum or Terebene Powder, also designed by Dr. Bond, is a combination of terebene with cupric sulphate and potassic bichromate, and possesses the same agreeable odour. It neutralises ammonia and sulphuretted hydrogen, and "acts as a powerful coagulator of albumen. It is PREVENTIVE MEASURES DISINFECTION. 387 specially adapted for disinfecting bowel-discharges, water- closets, urinals, and drains. 11. Sanitas is another disinfectant which has been highly recommended. It is manufactured chiefly from turpentine and water. As it possesses an agreeable odour, is non-poisonous, and does not stain, it is well suited for the sick-room. 12. Condys Fluid, red and green, consists of a solu- tion of potassium permanganate. It is essentially an oxidising agent, and as it is odourless, it is a very valu- able disinfectant in the sick-room. 13. Chloride of Aluminium, or " Chloralum" is a powerful disinfectant, and possesses the great advantages of being non-poisonous, inodorous, and very cheap. Pro- fessor Wanklyn says that " for removing fcetor and effluvia, it is better and 'more available than any agent with which I am acquainted. In this respect it is in- comparably superior to chloride of lime." Dr. Dougall, after a series of carefully-conducted experiments, likewise maintains that it arrests putrefactive change, and prevents the appearance of animalculse to a greater extent than any of the commonly employed disinfectants. Not being volatile, it cannot be regarded as an aerial disinfectant, but it is exceedingly useful in washing infected clothing, or as a scouring material for cleansing rooms. It is also an excellent sewage deodorant. 14. Chloride of Lime is very useful for disinfecting drains and faecal matters. 15. M'Dougall's Powder consists of carbonate of lime and magnesium sulphite. Like Calvert's carbolic acid powder, it may be employed very advantageously for cleansing purposes, and for the disinfection of masses of putrescent matter, sewage, or excreta. 16. Sidphate of Copper has been recommended by Dr. Dougall as possessing antiseptic properties equal to 388 PREVENTIVE MEASURES DISINFECTION. those of chloralum ; but it is not so suitable on account of its price and poisonous nature. 1 7. Chloride of Zinc. " Burnett's solution " consists of 25 grains of this salt to every .fluid drachm. It de- stroys ammoniacal compounds and organic matter. When used, it should be diluted with eight times its bulk of . water. 18. Ferrous Sulphate or Green Copperas has been largely used for disinfecting heaps of manure and sewage. It has also been recommended by Pettenkofer to be added to cholera evacuations for the purpose of destroying the contagium ; but it does not appear to have been attended with any good results. 19. Jeye's Disinfectant is very useful for disinfecting excreta or drains, and is a powerful deodoriser. Other sewage disinfectants have already been de- scribed in the chapter on the Purification of Sewage. 20. Cooper's Salts, which consist of a compound of sodium, calcium, and magnesium chlorides, have also been recommended as street and sewer disinfectants. 21. Potassium Bichromate has been extolled by Dr. Angus Smith, and chromic acid by Dr. Dougall, as being powerful antiseptics, but it is doubtful whether their price will ever permit of their being largely employed. Although the names of other agents could be added to this list, it embraces all the more useful disinfectants, and several which, while they are useful, are not so common. Probably the most reliable amongst them may be enumerated as follows : heat, sulphurous acid, car- bolic acid, Condy's fluid, chloralum, ferrous sulphate, chloride of zinc, chloride of lime, M'Dougall's and Cal- vert's powders, terebene, cupralum, sanitas, charcoal, and Jeye's disinfectants. PREVENTIVE MEASURES DISINFECTION. 389 SECTION III. PRACTICAL DISINFECTION. 1. Hygiene of the Sick-room. In all cases of highly infectious disease, if the patient is not removed to a hospital, the first duty to be attended to is the enforce- ment of a strict domestic quarantine by isolation of the patient whenever it is possible ; the next point is to make certain that the room is well lighted and sufficiently ventilated by means of open windows, and fires if neces- sary ; and the third point is to require the instant re- moval of all extraneous furniture, such as carpets, curtains, and the like. The attendant on the patient should receive strict and precise injunctions, not only with regard to the nursing of the patient, but also with regard to the main- tenance of the utmost cleanliness in the room ; the dis- infection of excreta, slops, soiled linen, etc., and their immediate removal afterwards ; and other points of detail depending upon the special nature of the disease and the circumstances of the patient. Although aerial disinfectants v may be regarded as of doubtful efficacy in the sick-room, they are deemed to be useful or expedient by many ; and, when properly selected and managed, it may be said, at all events, that they do not do any harm, if they are not productive of much good. The great danger is, that when employed without due precaution, they may only serve to disguise the signs of insufficient ventilation, and in this way con- duce to inattention as regards this most essential point. If they are employed at all, they should not be irritating to the patient. Hanging rags steeped in disinfectant solutions about the room is not to be commended, but a sheet moistened with a strong solution of chloralurn, sanitas, cupralum, or Condy's fluid, and suspended out- side the door of the room, is advantageous to complete 390 PREVENTIVE MEASURES DISINFECTION. the isolation of the patient. The infected clothing, etc., should be received into a tub containing chloralum, san- itas, or carbolic acid, and the ejecta, etc., should be in- stantly covered with one or other of these disinfectants and removed. Care must also be taken, in using different disinfectants, that they do not counteract each other ; for example, carbolic acid decomposes Condy's fluid. Further, the inunction of the body of the patient, in certain of the exanthematous infectious diseases, and especially scarlet fever, with camphorated oil, or a mixture of terebene and sweet oil, or a weak solution of glycerine and carbolic acid, followed by disinfecting baths during convalescence, is attended with the best results. 2. Disinfection of Empty Rooms and Uninhabited Places. After a case of infectious disease, the room should be thoroughly cleansed and disinfected. The furniture should be washed with a strong solution of chloralum (three or four ounces to the gallon of water), or with carbolic acid or terebene soap, and the room, as far as possible, emptied. Afterwards the floor and wood- work should also be thoroughly washed with disinfectant soap, and the paper should be removed. After closing doors, windows, and other openings, sulphurous acid gas should be generate^ in large quantities in the manner already described, and the room kept closed for several hours. After this, the door and windows should be thrown open, and in a few days the ceiling should be washed with quick lime and whitened, the walls repapered, and the floor and wood-work thoroughly washed with water and some disinfectant soap. 3. Disinfection of Clothing, Bedding, etc. Any mate- rial of this description which cannot be injured by being washed, should be steeped in a solution of chloralum or carbolic acid, and boiled. If Condy's fluid be used, the material should merely be immersed, and afterwards 1'KEYENTIVE MEASURE* DISINFECTION. 391 rinsed out in cold water, otherwise the solution will stain. In all cases, however, when it can be carried out, the clothing, bedding, etc., are best disinfected by being exposed for an hour at least to a dry heat of about 240 or 250 Fahr., and for this purpose every town of any dimensions should be provided with a hot-air disinfecting chamber for public use. Such a chamber is built of brick, and is heated by a coil of hot-air pipes lying underneath a perforated grating, and communicating with a furnace which opens outside. The one in use in Dublin cost 400. Dr. Kansome of Nottingham, as already stated, has devised a specially constructed disinfecting chamber, which, while it secures a sufficiency of heat, prevents the articles from being scorched. In connection with every such chamber in large towns there should be a covered van or hand-cart for conveying infected articles, and great care should be taken, by the free use of disinfectants, or by wrapping the articles in a sheet moistened with a strong disinfecting solution, to prevent any risk of spread- ing disease. A small portable disinfecting chamber is much needed for rural districts. The hair of infected mattresses should be teased out, fumigated, and exposed to the air, if the mattresses cannot be disinfected in a hot-air chamber. Eags and other articles which can be spared should be destroyed by fire, but so as not to create nuisance. When clothing cannot be disinfected by heat, Dr. Kansome has proposed that the different articles should be placed, layer on layer, in a box, with hot sand or bricks placed at the bottom, and sprinkled over with carbolic acid ; but a better plan is to hang them up in a small room and disinfect them with sulphurous acid gas. 4. Disinfection of Water-Closets, Urinals, Sinks, etc. In any district where an epidemic prevails or is threaten- ing, disinfection of all water-closets, etc., should be carried 392 PREVENTIVE MEASURES DISINFECTION. on systematically, either with solutions of chloride of lime, chloralum, cupralum, carbolic acid, copperas, or Burnett's fluid. Cooper's salts might be used for the streets, lanes, and open courts. Any manure-heaps or other accumulations of filth, which it is inexpedient to disturb or impossible to remove, should be covered with powdered vegetable charcoal to the depth of two or three inches, or with a layer of fresh dry earth, or with freshly- burnt lime, if charcoal cannot be obtained. Cesspits and midden-heaps may be disinfected with solutions of cop- peras (3 Ibs. to the gallon of water), or with cupralum or chloralum (1 Ib. to the gallon of water). It need hardly be said, however, that in a town or district well looked after by the sanitary authorities, no such filth-accumula- tions would be allowed to take place at any time. 5. Disinfection of the Dead Body. When a patient dies of a highly infectious disease, such as smallpox or scarlatina maligna, the body should be washed with a very strong solution of carbolic acid or chloralum, or, better still, enveloped in a sheet saturated with such solution, and placed in the coffin as soon as possible, disinfectants being again freely used, and the lid screwed down. The burial should take place without delay ; or in crowded districts, and in towns where a mortuary is provided, the dead body should be at once removed thither. The linen worn by the patient at death, if not buried with the body, should be destroyed by fire ; but when this cannot be done without creating nuisance, the burning should be effected at some distance from houses, or the bedding may be saturated with quicklime, and buried. It may be urged that many of these directions are needlessly minute ; and that, in fact, they cannot possibly be carried out in perhaps the great majority of cases. In answer to such objections let it be said, once and for all, that no labour is wasted which aims at preventing the PREVENTIVE MEASURES DISINFECTION. 393 spread of disease, even though it be often attended with failure ; and that, however limited be the means or oppor- tunity of carrying out preventive or precautionary mea- sures, such means and such opportunity should always be used, so as to be productive of the best possible results under the circumstances. Although a number of disin- fectants have been mentioned, it is always advisable that only a few, and those deemed the most efficient, should be used. Thus, for use in the sick-room, terebene or sanitas appears to be one of the most suitable ; for steep- ing clothing, a solution of carbolic acid or sanitas ; for disinfecting drains, closets, etc., chloride of lime, Jeye's disinfectant, or carbolic acid powder ; and for fumigation, sulphurous acid gas. For more special directions, see Appendix. 94 VITAL STATISTICS. CHAPTEE XV. VITAL STATISTICS. VITAL statistics may be defined as the science of figures applied to the health-history of communities. They deal with the principal events or phenomena of human life, the births, marriages, and deaths ; the various diseases from which people suffer or die, together with all the influences which affect vitality. In other words, the units of which they are composed consist mainly of persons living and of persons dying, and these units are classified or grouped under certain definite characteristics, such as age, sex, occupation, and disease. The analysis of these units or elementary facts, observed in their various rela- tions to time and place, and dealt with according to strict numerical method, lies at the foundation of all sound inquiry, and supplies the only true criterion of sanitary progress. SECTION I. SOURCES OF INFORMATION. In briefly discussing this subject for the purposes of the health officer or sanitarian, it will be convenient to refer at the outset to the two main sources from which the data which constitute vital statistics are derived, namely, the census returns, and the returns of births, marriages, and deaths, supplied by registration. As all these returns particularise the locality of every unit, whether supplied VITAL STATISTICS. 395 by census or registration, the units themselves can be readily classified according to various divisions or sub- divisions of the country, such as counties, towns, unions, parishes, villages, or streets, or according to urban and rural districts, as defined by the Public Health Act, 1875. For purposes of registration the country is divided into registration and sub -registration districts, which bear a more or less definite relation to counties, towns, and unions ; while for sanitary purposes the par- ticular returns, which apply to every district, however small or however large, can be obtained by every sanitary authority throughout the country from the district regis- trars. The management of the census, and the entire charge of the vital statistics of the United Kingdom, are entrusted to three Registrars-General, viz. one for Eng- land and Wales, one for Scotland, and one for Ireland, who publish yearly and quarterly reports for the whole country, and weekly reports for certain large towns. 1. The Census. The census, or actual enumeration of the people, is effected in Great Britain every ten years. The first enumeration was made on March 10, 1801, and the last on April 4, 1881, so that the recent census was the ninth enumeration of the inhabitants of this country. In order to secure accuracy of returns it is essential that the census should be taken rapidly and simultaneously ; and this is effected by issuing schedules to every householder beforehand, who has to enter all the particulars concerning every one sleeping in the house- hold on the night of the date fixed for the census. These schedules are all scrutinised and collected on the follow- ing day by the appointed enumerators, and in due course forwarded to the office of the Kegistrar-General, where they are tabulated and made available for statistical purposes. It need hardly be said that the taking of a census 396 VITAL STATISTICS. does not consist merely of a simple enumeration of the people. Amongst other items, the schedule returns con- tain particulars of the name, sex, age, rank, profession or occupation, condition, relation" to head of family, and birthplace of every living person who passed the night of the date of the enumeration in every house throughout the kingdom. When these returns are fully classified and analysed, they not only give the -number of inhabited and uninhabited houses in every parish, town, union, or county throughout the kingdom, together with the number of inhabitants, but the population can be grouped accord- ing to ages, sex, occupation, etc., thus supplying a vast storehouse of statistical information, which is of the highest value. The following table, from the Preliminary Keport of the 1881 Census, is interesting, as showing the growth of the population of England and Wales, and the enormous increase in the population of London, during the present century : Year of Enumeration. Population in England and Wales and in London at the Nine Enumerations. England and Wales, j London. Persons in London to 100 in England and Wales. 1801 . . . 8,892,536 10,164,256 12,000,236 13,896,797 15,914,148 17,927,609 20,066,224 22,712,266 25,968,286 958,863 1,138,815 1,378,947 1,654,994 1,948,417 2,362,236 2,803,989 3,254,260 3,814,571 10-78 11-20 11-49 11-91 12-24 1318 13-97 14-33 14-69 1811 1821 1831 1841 1851 1861 1871 1881 The aggregate population of England and Wales at the last census, including the population of London, con- sisted of 12,624,754 males and 13,343,532 females, show- VITAL STATISTICS. 397 ing an excess of females over males of 718,778. Further, it is shown that the rate of increase in the aggregate population is almost entirely dependent upon two factors, namely, the birth-rate and the death-rate ; the effects of emigration, immigration, or other movements of the popu- lation, being found to be comparatively insignificant. The rapid growth of the past decennium was also ascertained on analysis to be due to the fact that the birth-rate was unusually high, while the death-rate was much below the average. This is shown in the following table, which applies to England and Wales : Mean Annual Mean Annual Birth-rate. Death-rate. 1841-1851 32-61 22 '33 1851-1861 34-15 22 '25 1861-1871 35-24 22 '50 1871-1881 35-35 21 '27 In the words of the report, " the higher birth-rate in 1871-81, as compared with the preceding decade, im- plies the addition of 26,774 extra members to the com- munity ; while the lower death-rate implies the survival of 299,385 persons who, with the previous rate of mor- tality, would have died." What is called " the natural increment of the people " is represented by the excess of births over deaths, while the " actual increment " can of course only be determined by enumeration. During the last decennial period the difference between the natural and actual increment only amounted to 0*74 per cent, the former representing an increase of 15*08 per cent upon the population at the beginning of the period, while the latter represented an increase of 14' 3 4 per cent. The following table gives the population of the United Kingdom at the censuses 1851-81 inclusive: 398 VITAL STATISTICS. 1851 1861 1871 1881 United Kingdom . 27,745,949 29,321,288 31,845,379 35,246,562 England .... 16,921,888 18,954,444 21,495,131 24,608,391 Wales 1,005,721 1,111,780 1,217,135 1,359,895 Scotland .... 2,888,742 3,062,294 3,360,018 3,734,370 Ireland .... 6,574,278 5,798,967 5,412,377 5,159,839 Isle of Man . . . 52,387 52,469 54,042 53,492 Channel Islands . . 90,739 90,978 90,596 87,731 Army, Navy, and "j Merchant Seamen V 212,194 250,356 216,080 242,844 abroad . . . . J 2. Calculated Estimates of Population. Having pointed out so much concerning the actual census of the people, it becomes necessary now to refer to the method of estimating populations adopted by the Kegistrar- General for years intervening between one census enume- ration and the next. This method of calculation is based, as regards' the country generally, and large and growing populations, on the assumption that the rate of increase which prevailed Between the last two census enumera- tions will be maintained until the next census is taken. The estimate of the population of a town or sanitary dis- trict thus obtained becomes the basis upon which the birth-rate, death-rate, and other rates are calculated, and it need hardly be said that the nearer the estimate ap- proaches the actual number of the population the more strictly reliable will be the statistical results. The method pursued by the Eegistrar-General requires the use of logarithms, and is lucidly described in a leading article in the Sanitary Record for March 1879. In the article in question the population of Sheffield is dealt with by way of illustration, and this is stated as amount- ing to 185,172 at the census of 1861, and 239,947 at that of 1871, giving an increase of 54,775 persons VITAL STATISTICS. 399 during the intervening period. The article then goes on to show that " the rate of increase can most conveniently and most simply be calculated by the aid of logarithms. Instead of taking the difference between the population enumerated in 1861 and 1871, the difference between the logarithms of these numbers affords the true method for ascertaining the rate of increase. The logarithm of the population of Sheffield in 1861 is 5*2675753, and that of the population in 1871 is 5*3801136 ; the dif- ference between these logarithms is 0*1125383, which is the logarithm of the rate of increase of population in Sheffield during the ten years 1861-71. If this logarithm of the rate of increase be added to the logarithm of the population in 1871, the number corresponding to this new logarithm will be the estimate of the population at the next census in 1881, which will be found to be 310,922 (or 70,975 more than the enumerated popula- tion in 1871). Having obtained the logarithm of the ten years' increase (0 '1125383), a tenth of this will give us the logarithm of the annual rate of increase ; by in- serting a cypher to the left of the logarithm we shall divide it by 10, and 0*0112538 will be the logarithm of the annual rate of increase. The Eegistrar-General usually estimates his populations, for calculation purposes, to the middle of the year, and as the census is taken at the end of March or the beginning of April, a quarter of the logarithm of the annual rate has to be added to the logarithm of the enumerated population to obtain the logarithm of the estimate for the middle of the year 1871. The logarithm of the annual rate in Sheffield divided by 4 gives 0*0028135, which, added to the logarithm of the enumerated population in 1871, gives the logarithm of the population in the middle of 1871, namely, 5*3829271. Having thus obtained the logarithm of the population in the middle of 1871, the successive addition thereto of 400 VITAL STATISTICS. the logarithm of the annual rate of increase (0-0112538) will give the logarithm of the population in the middle of 1872, 1873, and so on up to the middle of 1881, by which time a new census will give us a new starting- point. The addition of eight and a quarter times the logarithm of the annual rate of increase to the logarithm of the enumerated population of Sheffield in 1871 gives the logarithm 5 '4 729575, the number to which is 297,138; this is the Eegistrar-General's estimate of the population of the borough of Sheffield in the middle of this year. " The reverse operation, that is, deducting the loga- rithm of the annual rate of increase from the logarithm of the estimated population in the middle of 1871, will give the logarithm of the population in the middle of 1870 ; and by repeating this operation the logarithm of the populations in the middle of each of the years back to 1861 may be obtained." It may be interesting to note here that though the estimate of the population of Sheffield in 1881 was 310,922, the actual population as enumerated at the census of that year was only 284,410, showing that the rate of increase which prevailed during 1861-71 was not maintained during the last decennial period. But unless the census is taken at shorter intervals, this discrepancy between the calculated and the actual increase of large towns cannot well be avoided. In small and slowly-increasing districts the following method of calculation will give a fairly approximate esti- mate of the population. Add to the population of the district as enumerated at the last census a tenth of the difference between that number and the number obtained at the previous census for each year that has elapsed since the last census. This will give the estimated popu- lation for the end of the first quarter of any given year, VITAL STATISTICS. 401 that being the period of the year at which the census is taken. But inasmuch as the death-rate is calculated on the estimated population of the district at the close of the second quarter or middle of any year, it is evident that a fourth part of the annual increment, or a fortieth part of the actual increase, of population which has taken place between the two censuses must be added to represent the increment for the additional quarter. As regards new and rapidly-increasing districts, how- ever, this method of calculation will not apply, and in such cases it is desirable, when possible, to ascertain the number of inhabited houses for the year, which may generally be obtained from the assessment books. An approximately correct estimate of the population can then be obtained by multiplying the average number of in- habitants per house, which can be ascertained without much trouble, by the number of occupied houses. 2. Registration. Ever since the days of Queen Elizabeth, births, deaths, and marriages have been regis- tered in the different parishes throughout England ; but it was not till the year 1837 that the Legislature passed an Act which provided that for the future all these entries should find a place in a national register, and that as regards deaths the various causes or diseases should be certified by the medical attendant. That the important office of the Kegistrar- General of England, which was established by that Act, has been productive of a vast amount of benefit to the health of the nation, and indeed has largely stimulated other countries to follow in the wake of sanitary progress, there can be no doubt. The first annual report of the Eegistrar-General, which was drawn up by the late Dr. Farr, appeared in 1839, and from the date of his appointment as Superintendent of the Statistical Department up to the date of his retire^ ment in 1879, his was the master-mind which, by a wide 2 D 402 VITAL STATISTICS. yet accurate induction from statistical data, laid the foundations of public hygiene, and at the same time enlarged and established the principles of medical science. In England and Wales there are over two thousand registrars and superintendent-registrars, whose duty it is to collect and forward to the central office at Somerset House all the certificates returned to them throughout the country. These, as already stated, apply to births, marriages, and deaths. a. Registration of Births. The chief data in these returns are the sex, the date of birth, the place of birth, the number of births (twins or triplets), legitimacy, and the residence of the parents. b. Registration of Marriages. These returns give the name, age, occupation, residence, and condition of husband and wife. c. Registration of Deaths. The principal data in these returns are the date, name, residence, age, sex, occupation, condition (whether single, married, or widowed), and the fatal disease or cause of death. In the case of children the age is stated in days, weeks, or months up to two years. But of all the data the most important to the hygienist is the cause of death, which has to be certified by the medical attendant, or, in cases of inquest, by the coroner. To ensure accuracy of statistical results it is highly essential that the cause of death should be clearly diagnosed, and certified according to the nomenclature of diseases drawn up by the Eoyal College of Physicians, and adopted by the Eegistrar- General. But it must be confessed that, apart from errors in diagnosis, which frequently occur, the cause of death is too often certified in a haphazard sort of way, and with but little regard to correct medical terminology. As a rule, however, these inaccuracies apply for the most part to causes of disease which do not come under sanitary VITAL STATISTICS. 403 control ; and in this respect, therefore, they do not vitiate statistical results to any appreciable extent, except when the primary cause of death is not certified. For example, a case of enteric fever often succumbs to pneumonia ; a case of scarlatina to nephritis ; a case of measles or whooping-cough to bronchitis; a case of phthisis to diarrhoea ; a case of rheumatic fever to endocarditis and so on. Now, in all such cases it is of the utmost importance that the primary cause should be certified as well as the secondary, because the former is the cause which should be classified as the actual cause of death. Accuracy of data, uniformity of data, and completeness of data, are all of them indispensable to correct statistical analysis. But, in addition to the registration of deaths, it has long been urged by leading sanitary reformers, that no true estimate of the vitality of the nation can be formed, unless a national system of registration of cases of sick- ness is also established. It is true that to a certain limited extent this has been attempted by the Local Government Board, by issuing instructions to clerks of unions to furnish weekly returns of all new cases of sick- ness occurring among paupers, whether in-door or out- door, to the medical officers of health of their respective districts ; but the information thus supplied is often of a very incomplete kind, and except, as regards cases of fever or infectious disease, is practically of little value. Of far greater importance is it for purposes of sanitary defence that some system of compulsory notification of all cases of dangerous infectious disease should be adopted for the country generally, such as is now in force in several large towns, because without prompt information of early cases, preventive measures are often of little avail, and especially in districts where proper hospital accommodation has been provided. 404 VITAL STATISTICS. SECTION II. CLASSIFICATION. The data thus obtained are classified or grouped under various headings. For example, so far as the duties of the medical officer of health are concerned, the births are classified according to sex, while the deaths are classified according to sex, ages, and diseases. In large urban dis- tricts the system of classification usually adopted is that of the Kegis trar- General, ^but for small urban or rural districts the limited tabular returns required by the Local Government Board will be sufficient. In either case, however, printed forms should be used for classification, and arranged to contain all the data for weeks, months, or quarters. In classifying data of any kind, it is essential that the individual units should have precise and definite characters, so that every unit in a group should be strictly included in that group. Then, again, the dividing char- acter of every group should be so distinct and clearly defined as to afford no room for doubt under which group or heading every unit should be classified. Care also should be taken that no unit should be classified so as to appear in two allied groups at the same time. Thus, we will suppose that a death has been returned as due to phthisis as the primary, and diarrhoea as the secondary, cause ; it would obviously vitiate the results if the single case were classified under the heading of diarrhoea, and also under that of phthisis. SECTION III. STATISTICAL EESULTS. After the data or units have been correctly classified, it becomes possible to compare and discuss their numerical relations. For this purpose a constant numerical standard VITAL STATISTICS. 405 must be adopted, and in vital statistics it is the rule to state this relation or rate as so inuch per cent or per 1000, or some other multiple of 1000. 1. Birth-Rate. The birth-rate of a population or community is obtained by comparing the total number of births occurring in a year and the total population esti- mated, as previously shown, at the middle of the same year. It is usual to represent it as a rate per 1000 of the population living in the district, at all ages. Thus, we will suppose that the estimated population of a dis- trict is 11,902, and that the number of births registered in the district during the year amounted to 384, then the birth-rate is obtained as follows : 11,902 : 1000 : : 384 : X, or annual birth-rate per 1000 = ,, = 3 2 '2. The rate of illegitimate births is generally represented as a percentage of the total number of births. Thus, the total number of births registered in England and Wales during 1880 amounted to 881,643, of which number 42,542 were born illegitimate, being in the proportion of 4* 8 to every 100 children born. Male births are everywhere more numerous than female,' but in England and Wales the proportion of boys to girls is smaller than in any other European country. This is shown in the following table from the Eegistrar- General's Eeport for 1880, which gives the average number of male births to 100 female births, for the ten years 1870-79 : Italy Austria France Switzerland German Empire 107-1 106-8 106-4 106-3 106-2 Holland . . . .106-1 Belgium . . . .105-9 Scotland . . . . 1057 Ireland . . . . 105 '6 England and Wales . . 103'9 406 VITAL STATISTICS. The following table gives the mean annual birth- rate in England and "Wales, and other European States, during the period 1876-80 : MEAN ANNUAL BIRTHS PER 1000 PERSONS LIVING, 1876-1880. COUNTRIES. Mean Annual Birth-rate 1876-80. COUNTRIES. Mean Annual Birth-ratel 1876-80. England and Wales Denmark .... Sweden . 35-4 31-9 30-2 Switzerland . . . German Empire . . The Netherlands 31-3 39'3 36'4 Austria .... Hungary 39-1 43'6 Belgium .... Italy 32-0 36'6 The high birth-rates which prevail in large urban districts are in great measure due to' the fact that the marriage-rate is higher, and that women marry younger than they do in country districts; while another cause which no doubt" operates to a considerable extent is the high rate of infant mortality, thus shortening the intervals of child-bearing, by the early deaths of the new-born. In fashionable towns, where large numbers of unmarried ser- vants are employed, and where a large proportion of the resi- dents are retired people, the birth-rate is always very low. 2. Marriage-Rate. This, like the birth-rate, is usually calculated as a rate of persons marrying per 1000 of the population living in the middle of the year. The marriage- rate in England and Wales during 1879 was 14*4 per 1000 of the population, while the average of the ten years 1871-80 was 16'1 per 1000. 3. Mortality. (1.) Total Annual Death-Rate. What is called the general death-rate, or total annual death-rate, of any dis- trict or community, is determined by means of a ratio VITAL STATISTICS. 40 7 between the number of deaths occurring during the year and the estimated population in the middle of the year, and, like the birth-rate, is represented as a rate of so many deaths per 1000 of the estimated population. Thus, we will suppose that the estimated population of a district amounts to 22,151, and that the number of deaths which occurred in the district during the year amounted to 335, then the total annual death-rate would be calculated as follows : 22,151 : 1000 : : 335 : X, or X = 00 ' = 15*1, where X represents the total 2> J, 10 1 annual death-rate per 1000. In the great majority of sanitary districts with com- paratively small populations, the total annual death-rate does not represent the actual death-rate, and corrections must be made for deaths of persons not belonging to. the district, which occur in hospitals, workhouses, asylums, or among visitors, and for the deaths of persons belonging to the district which occur outside the district. Take, for example, the statistics of a town of some 10,000 inhabitants in the centre of a union of some 45,000 inhabitants. The town is a separate sanitary district, but contains the workhouse for the whole union. It is evident that the death-rate for the town would be repre- sented as larger than it really is if no correction were made for the deaths which occur in the workhouse ; while, on the other hand, the death-rate of the surround- ing rural district would appear less than it actually is, unless the quota of in-door pauper deaths belonging to it is added to the total number of deaths. To make these corrections, the statistics of deaths occurring in these in- stitutions, giving full particulars of age, sex, and residence, must be obtained. In populous urban districts, however, 408 VITAL STATISTICS. if the number of deaths occurring amongst strangers be not excessive, they may fairly be included in calculating the death-rate, because in this case they may be con- sidered as fairly representing the deaths of those persons belonging to the district who have died elsewhere. So far, then, the problem of calculating the annual death-rate of any town or district becomes a very easy matter when the statistics are summarised for a whole year. But in respect to some large towns it is customary for the health officer to publish weekly, monthly, or quar- terly reports, and as all the rates given in these reports are calculated as annual rates per 1000 of the population living in the middle of the year, the problem becomes con- siderably more complicated. When monthly reports are submitted some medical officers of health calculate the annual rates by taking five weeks for the months of March, June, September, and December, and four for the other months ; but this method, though convenient, is not strictly accurate, and it is much preferable to adopt the method pursued by the Eegistrar-General. This is so fully and clearly described in an article which appeared in the Sanitary Record of August 1875, that it may be fitly quoted here : " In the first place it is scarcely necessary to say that all the rates now published by the Eegistrar-General, whether they relate to a year, a month, or a week, are annual rates to 1000 persons living ; that is, these published rates represent the number of per- sons who would die in the year in 1000 of each population, if the proportion of deaths to population recorded in the shorter periods of a week, or a month, or a quarter, were maintained throughout a whole year. " Let us take a rate of mortality from the Registrar-General's last weekly return relating to the seven days ending July 31 as an example. We find in Tables 1 and 2 of that return it is stated that the estimated population of the borough of Sheffield in the middle of 1875 is 267,881 persons ; that 127 deaths were recorded within the borough during the week under notice ; and further, that VITAL STATISTICS. 409 these deaths were equal to an annual rate of 24*7 per 1000 of this estimated population. Now for the operation by which this result is arrived at. "We have the deaths in a week, and the estimated population in which they occurred ; it is desired to find the number of the deaths which would occur in each 1000 of this population, if the same number of deaths were recorded in each week through- out a year. If a week were the correct fifty-second part of a year, it is obvious that either the deaths must be multiplied by fifty-two or the population be divided by fifty-two, in order to make the population and the deaths comparable. As, however, the correct number of days in a natural year is 365*24226, the number of weeks in a year is 52*17747. The Registrar - General, therefore, for the purpose of this weekly return, divides the estimated popula- tion of each of the towns dealt with by 52*17747, which gives what may be called the weekly population of each town. The population of Sheffield divided by 52*17747 gives a weekly popu- lation of 5134 persons ; this number serves as constant throughout the year 1875, by which to divide the number of deaths. The 127 deaths in Sheffield during the week ending July 31, divided by this so-called weekly population, gives an annual rate of 0*0247 to each person of the population ; and by removing the decimal point three places to the right, or in other words multiplying by 1000, we arrive at 24*7, which is the correct annual rate of mor- tality per 1000 of the estimated population of the borough of Shef- field during that week. It would undoubtedly be more logical to multiply the deaths by 52*17747 than to deal with the population * but this operation would have to be repeated each week, whereas there is a manifest convenience, and an arithmetical economy, in the reverse operation (the effect of which is, of course, identical), which supplies us with a constant that is applicable throughout the fifty-two weeks of 1875. For all practical purposes the multiplication of the deaths in a week by fifty-two, in order to divide them by the esti- mated population, will afford the means of arriving at an approxi- mately correct' annual rate of mortality ; or the reverse operation, the division of the population by fifty-two, may be resorted to. " For the calculation of annual rates of mortality in a month or a quarter the Registrar-General takes account of the number of days in each month or quarter, and it is found more convenient to deal with the population according to the method described in the cal- culation of the annual rate of mortality in a week. The populations to be dealt with are divided by 365*24226, and must then be mul- tiplied by the number of days in a month or a quarter, in order to arrive at the population which may be applied to the deaths in a month or a quarter ; by this means a scientifically correct annual 410 VITAL STATISTICS. death-rate in those respective periods will be obtained. Approxi- mately correct annual rates of mortality in a month or a quarter may be calculated by using a twelfth or a quarter of the population respectively, as the divisor of the number of deaths recorded in those periods ; but, inasmuch as the length of a month varies from twenty-eight to thirty-one days, and of a quarter, from ninety to ninety-two days, it is evident that a correct annual rate of mortality can only be calculated by taking into account this variation in the number of days in those periods, and that rates calculated without correction for these inequalities will differ from the rates published by the Kegistrar-General. " In conclusion, it may be noted that rates published in the quarterly. returns of the Kegistrar-General for the eighteen largest English towns relate to the period of thirteen weeks most nearly corresponding with the natural quarter, and that the population employed in this calculation is thirteen times that used for the rates in each week, and differs slightly from the population that would be used if the period of observation were three entire calendar months instead of thirteen weeks. The facts published in the quar- terly return for all other parts of the country, except the eighteen largest English towns, relate to the natural quarters of three calen- dar months, and the population used to produce the annual rates of mortality therein, are manipulated in the manner before described." The following table is interesting as showing the gradual and progressive decline in the death-rates of both urban and rural districts throughout England and Wales, and how greatly the urban have been gaining on the rural districts as regards healthiness : URBAN AND KURAL DEATH-KATES AT SUCCESSIVE PERIODS. MEAN ANNUAL DEATH-RATES PER 1000 LIVING. YEARS. Urban Districts. Rural Districts. Rural Rate below Urban Rate. In 4 years 1847-50 26-9 20-6 23 '4 per cent. In 10 years 1851-60 247 19-9 19-4 In 10 years 1861-70 24-8 197 20-6 In 10 years 1871-80 231 19-0 177 In the year 1880 21-9 18-5 15-5 VITAL STATISTICS. 411 In 1880, the general death-rate for England and Wales was 20'5 per 1000, while the mean death-rate of 1881 and 1882 was only 19/3 per 1000, being 2'1 below the mean rate of the preceding ten years 18*71-80. As regards sex, the male death-rate in 1880 was 21*8, and the female death-rate 19*3 per 1000, while out of equal numbers living of each sex, there died in the course of the year 1131 males to 1000 females. In addition to the birth-rate and death-rate, the other rates which are generally given in the reports of medical officers of health are the death-rate from zymotic disease and the rate of infant mortality. (2). Zymotic Death-Rate. What is called the death- rate from the seven principal zymotic diseases, or zymotic death-rate, is based on the total number of deaths occur- ring in a district during the year due to smallpox, measles, scarlatina, diphtheria, whooping-cough, fever (typhus, typhoid, and other or doubtful forms of continued fever), and diarrhoea. This, like the birth-rate or total annual death-rate, is calculated on the estimated population of the district, and is expressed as so many per 1000. Thus, we will suppose that in an estimated population of 22,438 the deaths from the seven principal zymotic diseases amounted to 48 during the year; the zymotic death-rate in this instance would be : 48 x 1000 22,438 =2'1 per 1000. According to the returns of the Eegistrar-General, the mean annual death-rate from the seven principal zymotic diseases in England and Wales in the three decades 1851-60, 1861-70, and 1871-80, was 3'87, 411, and 3*36 per 1000 respectively, while during the two years 1881-82 it had fallen to 2 -44. The annual death-rate from any other group of dis- 412 VITAL STATISTICS. eases, or from any single disease such as fever or phthisis, is calculated in the same way as the zymotic death-rate. Thus, the number of deaths attributed to " fever" which occurred in England and Wales during 1882 amounted to 7971, and as the estimated population at the middle of the year was 26,406,820, the death-rate from fever was In the three most recent decades it was equal to 0*91, 0-89, and 0*49 per 1000 respectively, thus showing a most marked decline. (3.) Hate of Infant Mortality. The rate of infant mortality, in the returns of the Registrar- General and in most health reports, is measured by the proportion of deaths of infants under one year to births registered, and is expressed as so many per 1000 births. Thus, we will suppose that the total number of deaths of children under one year of age which occurred in a given district amounted to 112 during the year, and that the births registered during the year amounted to 898, the rate of infant mortality estimated in this way will there- fore be 898 : 1000 : : 112 : X, __ 112x1000 rX= The annual rate of infant mortality in England and Wales for 1882 was equal to 141 per 1000 registered births, while the average rate for the ten years 1870-79 was 150 per 1000. (4.) Death -Bate at various groups of Ages. The death-rate of children under five years of age is sometimes expressed as a percentage of the total number of deaths, or VITAL STATISTICS. 413 it may be expressed as a rate per 1000 of the estimated number of children under five years living in the middle of the year. This estimate, like that of the population of a district, is calculated on the total number of children living under five years, as actually enumerated at the two last censuses, and published in the census reports. In the same way, the death-rate among persons of any given age is calculated from the estimated population living at that age, or the mortality per 1000 persons living may be stated according to groups of ages. This is shown in the following table from the Eegistrar- General's Eeport for 1880: ANNUAL KATE OF MORTALITY PER 1000 PERSONS LIVING AT TWELVE GROUPS OF AGES DURING 1880. REGISTRATION COUNTIES. ALL AGES. 5- 10 15 20 25 35- 45 55 65 75 85 and up- wards. ENGLAND. Average Annual ) Ratt in 25 Years > 184S-7U . . J 22-4 67-9 8-3 4-8 6-7 8'8 9-9 127 17-0 301 62-0 139-6 294-2 ENGLAND . . 20-5 64-4 6-3 3-3 4-8 6-1 77 11-5 16'0 30'4 61-2 131 '3 257-9 It is thus seen that the rate of mortality declines as age advances from birth to puberty, and then increases somewhat slowly to between 50 and 60. From the age 55 to the end, the mortality increases at such a rate as to be doubled every ten years. The table also shows that, comparing the rates of 1880 with the average annual rates (1848-72), there has been a marked lowering of the death-rates at all the groups of ages except that of 55-56. (5.) Death-Rate of Persons engaged in various Occu- pations. According to Dr. Farr, " the only way in which the mortality and the duration of life of miners, 414 VITAL STATISTICS. tailors, farmers, labourers, or any other class of men, can be accurately determined is to determine the ratio of deaths at each age to the living during a certain time in fact, to apply the same method to each class as is applied to determine the mortality and the mean lifetime of all classes in a town, in a district, or in the whole kingdom." The Supplements to the Twenty-fifth and Thirty-fifth Eeports of the Kegistrar-General contain a vast amount of statistical information bearing upon this important subject, showing to what extent the nature of the occupation influences mortality. (6.) Death-Hates in Different Localities. The general death-rate of the population is an average of high and low death-rates. High death-rates prevail in large towns and low death-rates in country districts, while in large towns it is found that the death-rate varies enormously in different parts. According to Dr. Farr, the mortality of districts increases with the density of their population ; but density of population is a complex condition,lmplying a combination of many separate morbific agencies, social and sanitary, which can only be ascertained by analysing and comparing statistical results, and especially with regard to age-distribution. Thus, the fashionable suburbs of large towns inhabited by the wealthy classes always contain a great excess of adults of the ages in which low death- rates prevail, while the birth-rate is also low. In the poorer and more crowded localities, on the other hand, there are no servants kept, and the birth-rate is high, so that the much higher mortality among infants and young children, compared with that of the adult population, raises the death-rate of the population to which they belong. But even when due allowance is made for age- distribution, it is found that the mortality in all the crowded parts of large towns is much higher at nearly all ages, and especially during childhood, adolescence, and VITAL STATISTICS. 415 the productive period of life, than in the better circum- stanced and more salubrious suburbs. (7.) Mortality in relation to Seasons. In estimating the significance of statistical results, no correct inferences can be drawn unless due attention is paid to the important influence of weather changes. Generally speaking, it may be said that during winter there is a predisposition to diseases of the respiratory organs, and that any fall below the mean average temperature is followed by an increased sick -rate and death-rate from these diseases. During summer, on the other hand, intestinal disorders become more prevalent, and any rise above the mean average temperature will be followed by an increased sick -rate and death-rate from diarrhoea and filth diseases generally. As a rule, the mortality is highest in the first quarter of the year and lowest in the third, the order from highest to lowest being first, fourth, second, third, but in many districts this sequence is found to vary considerably, and, indeed, it is found to vary in respect to the country generally, as the following table will show : YEARS. ANNUAL DEATH-KATES PER 1000 LIVING in the Quarter ending the last day of March. June. September. December. 1870-79 .... 1880 241 227 21'1 19-6 19-8 20-3 21'6 19-5 4. Longevity. This term may be used to embrace various statistical expressions, to which brief reference may be made, such as (1.) Mean Age at Death. The mean age at death of the population is obtained by dividing the sum total of the ages at death by the number of deaths. It is a very 416 VITAL STATISTICS. fallacious indication of longevity, and affords no true test of sanitary condition, because it fluctuates very largely, according to the varying proportions of young and old lives in different districts. In districts where the birth- rate is high the mean age at death will be comparatively low. The mean age at death of an entire generation alone gives accurately the mean duration of life, and this is determined by life -tables. According to Dr. Farr's life-table, which was based upon the census and mortality returns 1838-54*, the mean age at death of an English generation was 40'86 years. But inasmuch as the popu- lation of England is not stationary, but always rapidly increasing, by reason of the excess of births over deaths, the mean age at death of all who died during the years 1838-54 was 29'4 instead of 4O86. These averages have recently been supplemented by Mr. Humphreys, in a most valuable paper read before the Statistical Society of London (see Sanitary Record, May and June 1883), in which he discusses the whole bearings of improved sanitation, as evidenced by the recent decline in the English death-rate, and its effect upon the duration of life. According to Mr. Humphreys' new life-table, based upon the last census returns and the mortality returns of 1876-80, the mean age at death of an English generation is raised to 4 3 '5 6 years, while the mean age at death of persons dying in the five years 1876-80 was found to be about 3 2 years. In respect to sex, the mean age at death of males, according to Dr. Farr's life-table, was 39*91 years, and of females 41*85 years, while according to Mr. Humphreys' new life-table, the former has risen to 41*92 years, equal to an addition of 5 per cent to the mean duration of the lifetime of males, and the latter to 45*25 years, representing an addition of over 8 per cent to the average lifetime of all females born. It may here be explained that in constructing these VITAL STATISTICS. 417 life-tables, the calculations are based on a hypothetical generation of a million persons, consisting of the same pro- portion of males and females at birth and at subsequent ages, which is found to exist in the general population, and on the numbers of each sex dying each succeeding year, until the whole generation becomes extinct. (2.) Expectation of Life or mean after - lifetime at various ages. The expectation of life, calculated for years or groups of ages, represents the portion of future life which an individual at any age may reasonably ex- pect to enjoy ; and this, like the mean age at death or mean duration of life, is given in life-tables. Such tables afford the best means of testing the vitality of com- munities. The following life- table, given by Mr. Hum- phreys in the paper already referred to, not only shows clearly how the recent decline in the English death-rate has affected the mean duration of life in this country, but how it has affected the mean after-lifetime at various ages : Mean After-Lifetime (Expectation of Life at various Ages), from Life-Tables based upon English Mortality in 1838-54 and, 1876-80. Ages. Persons. Males. Females. 1838-54. 1876-80. 1838-54. 1876-80. 1838-54. 1876-80. 5 10 15 20 25 35 40-86 50-02 47-36 43-54 39-88 36-57 29-99 23-41 16-94 11-17 6-72 3-87 43-56 52-56 49-24 45-05 40-98 37-21 30-01 23-29 1675 11-19 6-81 4-00 39-91 4971 47-05 43-18 39-48 36-12 29-40 22-76 16-45 10-82 6-49 373 41-92 51-47 48-16 43-94 39-86 36-05 28-88 22-34 16-09 10-79 6-52 3-78 41-85 50-33 47-67 43-90 40-29 37-04 30-59 24-06 17-43 11-51 6-93 3-98 45-25 53-65 50-32 46-15 42-10 38-36 31-12 24-21 17-37 11-55 7-04 4-15 45 55 65 75 85 and upwards 2 E 418 VITAL STATISTICS. From this table it will be seen that the expectation of life has been increased at all groups of ages up to twenty- five among males, and up to fifty-five among females. But Mr. Humphreys, by a further analysis of the more extended life-tables, also shows that as much as 66 per cent of the increased duration of human life in England is lived at what is called the useful and productive period, namely, between 20 and 60 years, and not more than 34 per cent at the dependent periods either of childhood (0-20), or of old age (60 and upwards). These figures are very reassuring, and sufficiently refute the pessimist assertions which have recently been advanced with refer- ence to the reduced death-rate, that sanitary improve- ments have only resulted in an increase t in the passive endurance of life rather than in an increase of true vitality and genuine usefulness. (5.) Morbidity. This term has recently been intro- duced to denote the amount of illness existing in a given community, and is intended to express the sick-rate just as the term mortality expresses the death-rate. In the absence of any complete system of registration of cases of % disease, and taking into consideration the fact that disease often sets in so insidiously and is frequently so ill-defined, it becomes a matter of considerable difficulty to estimate the amount of sickness which may be pre- valent in any district during any stated period. Hitherto such estimates have been based mainly on the records of sick-clubs, benefit societies, army, navy, and police, and they apply solely to disabling sickness occurring amongst lives which may be regarded as selected. From such records of sick-time, Dr. Farr, in his supplement to the Thirty-fifth Eeport of the Kegistrar-General, has estimated that to one annual death in a body of men two men are on an average constantly suffering from sickness of some severity, or in other words, that to every death there are VITAL STATISTICS. 419 two years of severe sickness. In the police and some friendly societies, the constantly sick to every death that occurs are 2*8, while in the army at home the ratio is 4 '2, the difference being due to the prevalence of enthetic disease. With regard to diseases which, as a rule, occur only once during a lifetime, such as scarlatina, smallpox, and some of the other zymotic diseases, an approximate estimate of the number of cases occurring in a district can some- times be made from the number of deaths. Thus the ^ mortality occurring among cases of scarlatina admitted into hospitals has been taken as a basis for calculating the number of cases in any district from the deaths registered in such district, and the ratio estimated in this way has been given as about ten cases for every death. But such estimates are comparatively valueless, because, apart from the incompleteness of the data on which they are based, the mortality will vary very much according to the severity of the epidemic. Far more reliable statistics will doubtless be obtained after an extended experience of the registration of cases of infectious disease in those towns in which powers for compulsory noti- fication have been obtained. Concluding Remarks. In drawing conclusions from statistical data, it need hardly be said that great care must be taken to guard against fallacies. For example, the death-rate of a district may be comparatively low by reason of the preponderance of adult or selected lives, while the sanitary conditions are by no means satisfactory; or again, the total death-rate may not be above the average, while the death-rate in certain portions of the district may be excessively high. Generally speaking, the effects of sanitary improvements and precautionary measures are best indicated by a lowered death-rate from infectious diseases, fever, diarrhoea, and phthisis, and 420 VITAL STATISTICS. amongst children under five years from all causes. Indeed, it may be said that the death-rate of children under five years of age is in many localities a far more reliable criterion of the sanitary conditions affecting the health of communities than the total annual death-rate t even although every allowance is made for neglect, de- ficiency of food, mal-nutrition, and exposure. Nor, again, in drawing inferences from mortality returns, must the influence of social causes of disease be forgotten-, for the effects of intemperance, immorality, and early or in- judicious marriages, especially amongst the lower classes in all our large towns, can scarcely be over-estimated. (For further details see succeeding chapter and Appendix.) DUTIES UF MEDICAL OFFICERS OF HEALTH. 421 CHAPTEK XVI. THE DUTIES OF MEDICAL OFFICERS OF HEALTH. BY clauses 189 and 190 of the Public Health Act 1875, it is enacted that it shall be the duty of every urban and of every rural sanitary authority, throughout England and Wales, to appoint from time to time a legally -qualified medical officer or officers of health for the efficient execu- tion of the purposes of the Sanitary Acts. In the case of rural sanitary districts, such officers may be the district medical officers of unions, who are to a certain extent under the control of the Local Government Board ; but in the case of urban sanitary districts, those medical officers of health are alone subject to the control of the Local Government Board whose salaries are partly paid out of moneys voted by Parliament. Such sanitary autho- rities, therefore, as do not choose to receive assistance from the public purse in the payment of their health- officers, may appoint or dismiss such officers without the consent of the Local Government Board, and may issue such regulations for their guidance as they may from time - to time determine. In either case, however, the duties of the medical officer of health will, in great measure, be identical as regards the main points ; and hence the fol- lowing regulations, whicli have been issued by the Local Government Board for the guidance of medical officers of health whose appointments are made subject to the approval of the Board, may be considered as more or less 422 DUTIES OF MEDICAL OFFICERS OF HEALTH. applicable to all health officers. By an order, dated llth November 1872, which is still in force, these duties are thus denned : " The following shall be the duties of the medical officer of health in respect of the district for which he is appointed ; or, if he shall be appointed for more than one district, then in respect of each of such districts : " 1. He shall inform himself, as far as practicable, respecting all influences affecting or threatening to affect injuriously the public health within the district. " 2. He shall inquire into and ascertain by such means as are at his disposal the causes, origin, and distribution of diseases within the district, and ascertain to what extent the same have depended on conditions capable of removal or mitigation. "3. He shall, by inspection of the district, both systematically at certain periods, and at intervals as occasion may require, keep himself informed of the conditions injurious to health existing therein. " 4. He shall be prepared to advise the sanitary authority on all matters affecting the health of the district, and on all sanitary points involved in the action of the sanitary authority or authori- ties ; and in cases requiring it, he .shall certify, for the guidance of the sanitary authority or of the justices, as to any matter in respect of which the certificate of a medical officer of health or a medical practitioner is required as the basis or in aid of sanitary action. " 5. He shall advise the sanitary authority on any question relating to health involved in the framing and subsequent working of such bye-laws and regulations as they may have power to make. "6. On receiving information of the outbreak of any contagious, infectious, or epidemic disease of a dangerous character within the district, he shall visit the spot without delay and inquire into the causes and circumstances of such outbreak, and advise the persons competent to act as to the measures which may appear to him to be required to prevent the extension of the disease, and, so far as he may be lawfully authorised, assist in the execution of the same. " 7. On receiving information from the inspector of nuisances, that his intervention is required in consequence of the existence of any nuisance injurious to health, or of any overcrowding in a house, he shall, as early as practicable, take such steps authorised by the statutes in that behalf as the circumstances of the case may justify and require. DUTIES OF MEDICAL OFFICERS OF HEALTH. 423 " 8. In any case in which it may appear to him to be necessary or advisable, or in which he shall be so directed by the sanitary authority, he shall himself inspect and examine any animal, carcase, meat, poultry, game, flesh, fish, fruit, vegetables, corn, bread, or flour, exposed for sale, or deposited for the purpose of sale, or of preparation for sale, and intended for the food of man, which is deemed to be diseased, or unsound, or unwholesome, or unfit for the food of man ; and if he find that such animal or article is diseased, or unsound, or unwholesome, or unfit for the food of man, he shall give such directions as may be necessary for causing the same to be seized, taken, and carried away, in order to be dealt with by a justice according to the provisions of the statutes applicable to the case. " 9. He shall perform all the duties imposed upon him by any bye-laws and regulations of the sanitary authority duly confirmed, in respect of any matter affecting the public health, and touching which they are authorised to frame bye-laws and regulations. "10. He shall inquire into any offensive process of trade carried on within the district, and report on the appropriate means for the prevention of any nuisance or injury to health therefrom. "11. He shall attend at the office of the sanitary authority or at some other appointed place, at such stated times as they may direct. "12. He shall from time to time report, in writing, to the sanitary authority, his proceedings and the measures which may require to be adopted for the improvement or protection of the public health in the district. He shall in like manner report with ivspect to the sickness and mortality within the district, so far as he lias been enabled to ascertain the same. " 13. He shall keep a book or books, to be provided by the Military authority, in which he shall make an entry of his visits, ami notes of his observations, and instructions thereon, and also the date and nature of applications made to him, the date and result of the action taken thereon, and of any action taken on previous reports, and shall produce such book or books, whenever required, to the sanitary authority. " 14. He shall also prepare an annual report to be made at the t'lid of December in each year, comprising tabular statements of the sickness and mortality within the district, classified according to diseases, ages, and localities, and a summary of the action taken during the year for the preventing the spread of disease. The report shall also contain an account of the proceedings in which he has taken part or advised under the Sanitary Acts, so far as such pro- ceedings relate to conditions dangerous or injurious to health, and ul.-M> on account of the supervision exercised by him, or on lii.s 424 DUTIES OF MEDICAL OFFICERS OF HEALTH. advice, for sanitary purposes, over places and houses that the sanitary authority has power to regulate, with the nature and results of any proceedings which may have been so required and taken in respect of the same during the year. It shall also record the action taken by him, or on his advice, during the year, in regard to offensive trades, bakehouses, and workshops. ."15. He shall give immediate information to the Local Govern- ment Board of any outbreak of dangerous epidemic disease within the district, and shall transmit to the Board, on forms to be provided by them, a quarterly return of the sickness and deaths within the district, and also a copy of each annual and of any special report. ; " 16. In matters not specifically provided for in this order, he shall observe and execute the instructions of the Local Government Board on the duties of Medical Officers of health, and all the lawful orders and directions of the sanitary authority applicable to his office. "17. Whenever the Diseases Prevention Act of 1855 is in force within the district, he shall observe the directions and regula- tions issued under that Act by the Local Government Board, so far as the same relate to or concern his office." For the efficient and conscientious discharge of these duties, it is evident that a medical officer of health must make himself thoroughly acquainted with the fundamental principles of public and practical hygiene, with the general and local circumstances which may affect the health of the population in his district, and with the various clauses of the Public Health and other Acts which more immedi- ately concern his office. So much is left to his discre- tionary power in advising the sanitary authority, and in certifying as to what is or is not injurious to the public health, that he cannot but feel the grave responsibility which will devolve upon him, if through ignorance or neglect on the one hand, or through mistaken zeal and want of tact on the other, he fails to carry out his duties honestly, judiciously, and efficiently. As there is no doubt that considerable difficulty will be experienced at the outset by most health officers in regard to the mode in which their duties should be carried out, the various suggestions and practical details summa-r- DUTIES OF MEDICAL OFFICERS OF HEALTH. 425 ised under the following sections, may, it is hoped, prove as serviceable as they are reliable : SECTION I. NATURAL CONDITIONS AFFECTING THE HEALTH OF THE POPULATION CONTAINED IN THE DISTRICT. These comprise the geological and topographical characteristics of the district, the water-supply, and the climate. 1. Geological Conditions. Official information as re- gards these may be obtained from the Ordnance maps and the special sections published by the Survey or- General ; while fuller details could be readily collected from local sources. In most districts there will generally be found some one who has made the geology of the locality a special study. 2. Topographical Conditions. These relate to the situation of the various parts of the town or district, whether low-lying, elevated, or sloping. * 3. Water -Supply. The quantity and quality of the obtainable water-supply in a district will depend very much on the two previous sets of conditions. So also will the nature of the subsoil and the facilities for drain- age and sewerage. All this, however, has been fully explained in previous parts of this work. (See Chapters VI., VIIL, and XIII.) Speaking generally, the diseases which are found to be most largely associated with natural conditions in this country are phthisis, and probably also other lung diseases, ague, cancer, rheumatism, heart disease, diphtheria, and goitre. In this field of inquiry, Mr. Haviland's writings on the geographical distribution of disease will be found to be very serviceable. 4. Climate. Under this heading are comprised the 426 DUTIES OF MEDICAL OFFICERS OF HEALTH. meteorological conditions of the district, such as the daily temperature and rainfall, the force and direction of winds, the barometric pressure, the degree of humidity, and the amount of ozone. In most large towns these observations are already being carefully recorded, and where this is the case, the health officer should endeavour to obtain, through the sanitary authority, the record of the observations weekly. In districts where no such observations are made, it will be no part of his duty to supply this information, but at the same time it is necessary that he should take cognisance of meteorological fluctuations, because they con- stitute very important factors of health or disease in every district. SECTION -II. ARTIFICIAL CONDITIONS AFFECTING THE HEALTH OF THE POPULATION CONTAINED IN THE DISTRICT; such as 1. Habitations of the People. So far as possible the sanitary condition of every house in the district should be inquired into. Of course the health officer himself could not undertake such a laborious inquiry, but in towns it could be easily and efficiently carried out by the temporary appointment of one or more competent persons, who would be paid by the sanitary authority and directed by the health officer; while in small urban or rural districts it can be carried out by the sanitary inspector. In carrying out a systematic inquiry of this descrip- tion in rural districts, it is advisable that the inspector should complete the survey of one or more parishes or villages before submitting the details to the medical officer of health, who would then appoint a day for going over the survey with the inspector. During the inspection he should satisfy himself as to the accuracy of the returns, advise with regard to particular defects, and in this way DUTIES OF MEDICAL OFFICEKS OF HEALTH. 427 make himself fully acquainted with the sanitary condition of every part of his district in detail. The tabulated forms to be used for such a survey, when it is authorised by the sanitary authority, will vary slightly, according as the district is urban or rural. Those devised by Dr. Bond of Gloucester, although somewhat bulky, will be found to be well arranged and admirably suited for rural districts. They contain the following headings in the several columns : Number ; No. of case in nuisance book ; date of inspection ; situation and description of premises ; names of occupier and owner ; number of living rooms, sleeping rooms, and inmates ; nature, situation, and con- dition of closet-accommodation ; nature of water-supply ; defects in drainage, ventilation, or general condition of premises ; existence of any special source of actual or possible nuisance ; remarks by medical officer of health ; additional observations. With very rare exceptions, the inspector will meet with no opposition in carrying out the survey, nor the medical officer of health in obtaining any information with regard to any points which he may consider desirable. Further particulars with regard to the sanitary condition of premises, overcrowding, nuisances generally, and how to draw up reports, will be given in Section IV. (See also Chapter IX.) 2. Water -Supply. In districts where the water- supply is public, the medical officer of health should make himself acquainted with the quality of the water, amount per head, and the risks of pollution, both as regards the source of supply and the mode of distribution. The nature of the supply, whether constant or intermittent, the relation between mains and closets ; the situation and condition of cisterns ; the separation of cisterns for domes- tic supply from those supplying closets ; the situation of overflow pipes, and the like, are all points which should receive careful attention. In rural districts, the sufficiency 428 DUTIES OF MEDICAL OFFICERS OF HEALTH. of the water-supply, as well as its quality, the situation of wells, and the risks of pollution, should all be duly noted, and samples of suspicious well-water should be examined. In villages where the water-supply is in- sufficient, it will become a question for the medical officer of health to advise generally as to how this want may best be remedied, whether by providing one or more public wells, by introducing a public supply, by compelling neighbouring owners of property to unite in providing a sufficient supply under the new Public Health (Water) Act, by storage of the rainfall, or by carting water into the village to meet special emergencies, leaving of course all practical details to be dealt with by the sanitary en- gineer or inspector. (Chapters VI. and VII.) 3. Drainage, Sewerage, Scavenging, etc. In towns full information with regard to these conditions will be ob- tained from the borough engineer or town surveyor. Special attention should be given to the ventilation and flushing of sewers, and the condition of house-drains as regards ventilation, flushing, freedom from smell, and con- struction; while the ventilation of water-closets, soil- pipes, and, as far as possible, the severance of all direct communication of house-drains with sewers, are additional points of importance which should not escape notice. The efficiency of the scavenging arrangements should also be carefully inquired into. In country districts it will devolve upon the medical officer of health to report as to whether the drainage of particular villages is satisfactory, and to recommend or not, as he may think fit, as to whether a competent engineer should be called in to sur- vey and prepare plans. In certain cases, too, he will have to inquire and decide as to whether public scavenging has not become necessary to ensure adequate local cleanli- ' ness. (See Chapters XL, XII., and XIII.) 4. Factories, Workshops, Bakehouses, Public Institu- DUTIES OF MEDICAL OFFICERS OF HEALTH. 429 tions, Slaughter -houses, etc. These should be examined with reference to overcrowding, air-impurities, and the production of nuisances generally. (See Chapter III. and Section IV. of the present chapter.) Tactories already under Government inspection would not of course be sub- ject to the supervision of the health officer, except in so far as they prove to be a nuisance or injurious to the health of the neighbouring inhabitants. In country dis- tricts special attention should be given to the sanitary condition of village-schools, whether public or private, and also to the sanitary condition of graveyards. 'SECTION III. VITAL STATISTICS. In addition to obtaining a full knowledge of the natural and artificial conditions which affect the health of the population, the medical officer of health should also make himself acquainted with the vital statistics of his district. By referring to the more recent Quarterly and Annual Eeports of the Eegistrar-General, the books of the district-registrar, the abstracts of the Boards of Guardians, and any reports which have already appeared with regard to the health of the district, he will obtain all the statistical data representing its vital history for the past few years, as indicated by the number of the population, its rate of increase, the birth-rate, the marriage -rate, the rate of mortality, the prevalency of epidemic or other specially fatal diseases, the death-rate at different ages, the amount of pauperism, etc. From the last census returns, again, he will obtain much useful information as regards the areas, houses, and population, and the ages, civil condition, and occupation of the people. Amongst other works which will be found very ser- viceable, are the Digest of the English Census of 1871, by Mr. Lewis, and the Supplement to the Thirty-fifth 430 DUTIES OF MEDICAL OFFICERS OF HEALTH. Annual Eeport of the Kegistrar- General, published in 1875. This supplement contains Dr. Farr's Eeport on the Mortality of the Eegistration Districts of England during the years 1861-1870, a report which is full of information of the most varied kind, and exhibits in the most masterly way the wide range of logical deductions that can be based on vital statistics when properly tabu- lated and accurately arranged. Such a retrospect, it need hardly be said, would form a sound basis of local statistical knowledge to start with, and by pursuing the same course with regard to the registration and pauper returns, which should be obtained regularly, the medical officer of health will be in a position at all times to inform the sanitary authority concerning the prevalence of infectious and preventable diseases, and advise as to what steps should be taken. But as the death-rate gives no sufficient indication of the sick-rate, he should also obtain the pauper sick returns immediately after each meeting of the guardians, and as far as possible the returns from the public medical institutions in his district. Arrangements should likewise be made through the sanitary authority, that poor-law medical officers should report without delay the occurrence of any case of fever or infectious disease, and that the district-registrar should at once forward a return of any death from such disease. Further, if the medical officer of health is pre- cluded from practice, he will generally find that the medical practitioners in his district will give him much timely information, provided he is careful not to make himself too officious ; but until the registration of cases of infectious disease is rendered compulsory, the only returns which are provided for in the instructions of the Local Government Board are the returns of the district- registrar, the pauper sick returns, and such returns with regard to infectious disease which the sanitary inspector DUTIES OF MEDICAL OFFICERS OF HEALTH. 431 can obtain. Arrangements may, however, be made with local practitioners to report all cases of certain specified dangerous infectious diseases on payment of a fixed fee per case by the sanitary authority. The district -registrars throughout the country are instructed by the Kegistrar-General to forward the returns of births and deaths to the medical officer of health, and are allowed 2d. per entry for remuneration, which the sanitary authority is empowered by the Local Government to pay. The sanitary authority also supplies the blank forms, and defrays the expense of postage. Except as regards deaths from fever or other infectious disease, a return of which should be forwarded immediately, the usual returns of the registrar should be forwarded to the medical officer of health at the close of every week. Blank forms may be obtained from Messrs. Knight and Co., publishers, Fleet Street, London ; Messrs. Shaw and Sons, Fetter Lane, London ; or Messrs. Farrant and Frost, Merthyr-Tydfil. (See Appendix.) By means of the information supplied by these weekly returns, the medical officer of health is enabled to tabulate the mortality statistics in such a manner as will show the birth-rate, the total death-rate, the death-rate at different ages, the death-rate from zymotic disease, the connection between the total infantile or zymotic death-rate, and the sanitary or insanitary condition of various parts of his district, the prevalency of any particular diseases in cer- tain areas, and so on. If the district is a large urban one, the diseases may be classified according to sub-dis- tricts or streets, and if it be a large rural one, they may be classified according to sub-districts or parishes. In large urban districts the classification should be that used by the Eegistrar-General, or the system recommended by the Society of Medical Officers of Health. (See Appendix.) In small urban or rural districts, however, it is by no 432 DUTIES OF MEDICAL OFFICERS OF HEALTH. means necessary to compile elaborate tables, and the classification which is given in the quarterly returns to the Local Government Board, or some similar classification, will answer all practical purposes. For the sake of comparison it is much to be regretted that some uniform system of classification is not enforced in all districts, a simple sys- tem for rural and small urban districts, and a more elaborate system for urban districts containing say 25,000 inhabitants and upwards. In combined districts too, there is some chance of confusion arising from the fact that the registration sub-districts are frequently not conterminous with the several sanitary districts, inasmuch as small urban districts generally form part of a registration sub-district, the other part being included in a neighbouring rural sanitary district. What is required of the medical officer of health is that he should classify his returns honestly and with no preconceived ideas as to what the figures are to prove ; and although mistakes may sometimes be made in dia- gnosis, he is bound to classify the returns as he receives them, unless after due inquiry he is convinced that in exceptional cases such mistakes have been made. Even then it is essential, as a statist, that he should present the returns as they are sent in to him ; and if he has reason to question their accuracy, he should honestly state his reasons, after . as far as possible consulting with the medical attendant. This of course is always a delicate matter, requiring the utmost tact and conscientiousness, because under any circumstances it is an interference liable to be resented, and especially if the medical officer of health is not precluded from practice. But, whether the medical officer of health is in practice or not, enough has been said in the preceding chapter to show not only the necessity of constant and systematic attention on his part to the vital statistics of his district, but also the DUTIES OF MEDICAL OFFICERS OF HEALTH. 433 immense assistance which a logical use of them will afford him in estimating rightly the separate or com- bined influences of avoidable or removable causes of disease. (See Chapter XV.) SECTION IV. DUTIES REQUIRED OF THE MEDICAL OFFICER OF HEALTH FOR THE EFFICIENT EXECUTION OF THE SANITARY ACTS. As the health officer must "be prepared to advise the sanitary authority on all points involved in the action of the sanitary authority or authorities," it is necessary that he should make himself acquainted with the Public Health Act of 1875, and the other Acts or portions of them which more immediately concern his office. Previous to the consolidation of the various Sanitary Acts in the Public Health Act of 1875, the task of wading through these numerous enactments, so as to obtain a practical knowledge of the clauses affecting the duties of the health officer, was by no means an easy one. All this, however, is now very much simplified, and the only Acts which the health officer need consult, may be confined, with a few exceptions, to the Public Health Act, 1875, the Artisans' Dwellings Act, 1875, the Canal Boats Act, 1877, and the Public Health (Water) Act, 1878. And here it may be observed that though the Public Health Act permits the medical officer of health to exercise any of the powers with which an inspector of nuisances is invested, it is not his duty to search for nuisances. By all means let him make an inspection whenever he deems it necessary, or when he has reason to believe that the sanitary inspector is not properly attending to his duty, but he should avoid as far as pos- sible interfering with matters which in the first instance concern the office of the surveyor or sanitary inspector. 2 F 434 DUTIES OF MEDICAL OFFICERS OF HEALTH. He should, nevertheless, be fully qualified to advise and give suggestions, and in order to do so it is essential that he should be well acquainted with practical details. The clauses in the Public Health Act, to which special atten- tion should be directed, are classed in order as they appear in the list, under the following headings : 1. Sewerage and Drainage (clauses 13-26). The two most important clauses in this section, so far as the medical officer of health is concerned, are clause 19, which makes it incumbent on every local authority to have all sewers constructed, ventilated, and kept, so that they shall not be a nuisance ; and clause 23, which em- powers local authorities to enforce the drainage of un- drained houses, such drainage to be carried out in all particulars to the satisfaction of the surveyor. (See Chapter XL) . 2. Privies, Water-closets, etc. (clauses 35-41). These clauses give full powers to sanitary authorities to enforce closet accommodation, and to provide that all drains, water-closets, earth-closets, privies, ashpits, and cesspools, within their district, be constructed and kept so as not to be a nuisance or injurious to health. With regard to structural details, and especially the alterations which are required to remedy the defects which are so commonly connected with the closet accommodation of rural districts, see Chapter XL 3. Scavenging and Cleansing (clauses 42-47). By virtue of these clauses, sanitary authorities are empowered, or they may be required by order of the Local Govern- ment Board, to provide for the cleansing of streets and the removal of refuse ; and in localities where the scaveng- ing is undertaken by the sanitary authority, any occupier of premises may claim a penalty not exceeding five shil- lings a day from the local authority if they neglect, after due notice, to cleanse any earth- closet, privy, ashpit, or DUTIES OF MEDICAL OFFICERS OF HEALTH.' 435 cesspool, belonging to such premises. In all cases, there- fore, where the medical officer of health is convinced that public scavenging has become necessary, he ought to urge that this duty be undertaken by the sanitary authority, and if they refuse to comply with his request, he should have no hesitation in appealing to the Local Government Board to issue the necessary order. In places where there is no public scavenging, the local authority may make by-laws imposing the duty of cleansing footways and pavements adjoining premises, and of removing all offensive refuse from the premises, on the occupier. Clause 46 gives power to order the cleansing and purify- ing of houses on the certificate of the medical officer of health; and clause 47 imposes penalties in respect to certain nuisances occurring on premises in urban districts. (See Chapter XI.) 4. Offensive Ditches and Collections of Matter (clauses 48-50). These clauses provide for the obtaining of orders for cleansing offensive ditches lying near to or forming the boundaries of districts ; for the removal of filth-accu- mulations on the certificate of the sanitary inspector ; and for the periodical removal of manure from mews and other premises in urban districts. 5. Water-Supply (clauses 51-70). These clauses re- late to the general powers of sanitary authorities for sup- plying their districts with water, whether by waterworks or wells ; to provisions for the protection of water-supplies against pollution ; and to the closing, cleansing, or repair- ing of polluted wells. (See Chapters VI. and VII.) In the Public Health (Water) Act, 1878, power is given to enforce a wholesome supply for isolated houses or groups of houses if within a certain limit of outlay; and it is further enacted that no house which has been newly built or rebuilt shall be occupied unless such wholesome supply is first provided. The Act applies specially to 436 DUTIES OF MEDICAL OFFICERS OF HEALTH. rural districts, and if systematically carried out will be of immense service in improving the health of these districts. 6. Regulation of Cellar Dwellings and Lodging- Houses (clauses 71-90). Besides prohibiting the occupation of .cellars absolutely, or only under certain conditions, these clauses provide for the registration of common lodging- houses, and the issuing of by-laws for their regulation, and they also empower the Local Government Board to authorise the local authority to make by-laws in respect to houses other than common lodging-houses which are let in lodgings, or occupied by members of more than one family. As regards watering-places, and other fashion- able health-resorts, this last provision is one of great im- portance, inasmuch as it would not only ensure the removal of any sanitary defects from houses let in lodgings, but it also renders it compulsory on lodging-house keepers to give immediate notice to the sanitary authority in cases of infectious disease, and to take proper precautions. 7. Nuisances (clauses 91-111). As this section of the Public Health Act is a very important one, it may be considered more fully in detail. The several classes of nuisances are defined by the Act as follows : (1.) " Any premises in such a state as to be a nuis- ance or injurious to health." It need hardly be said that this definition, by reason of its vagueness, includes a great variety of sanitary defects, and, like the other definitions, implies injury to health, whether probable or actual, as a consequence of the nuisance. Unfortunately, too, this vagueness is; if possible," still further increased by the definition in the preamble of the Act, which states that " lands and premises include messuages, buildings, lands, easements, and heredi- taments, of any tenure." All this gives ample room for legal quibbles, but, so far as the duties of the medical officer of health and the sanitary inspector are concerned, DUTIES OF MEDICAL OFFICERS OF HEALTH. 437 there is usually little difficulty experienced in carrying out the intention of the Act. The sanitary defects im- plied in the definition have reference, for the most part, to the cleansing or whitewashing of dirty houses ; the repair of roofs that let in the rain ; the repair of walls and uneven floors ; the opening of fastened windows to improve the ventilation ; the repair of closets ; the relay- ing of defective drains ; the ventilation, trapping, or disconnection of house-drains ; the removal of privies or pig-styes abutting against outside walls; the prevention of dampness as far as possible ; the repair of yards, and, especially in rural districts, the sanitary improvement of farm-yards adjoining the dwelling-houses. When it is not possible to put a house into habitable repair, or when the necessary repairs are not carried out in compliance with the notice issued by the sanitary inspector, power is given, by clause 97, to close the house by order of a Justice. With regard to the difficulties of dealing with the question of defective house-accommodation, see Chapter IX. (2.) "Any pool, ditch, gutter, water -course, privy, urinal, cesspool, drain, or ashpit, so foul, or in such a state as to be a nuisance, or injurious to health." This definition requires no further comment than this, that whenever any offensive smell is given off by any pool, ditch, etc., whether it be in the proximity of dwellings, or near any frequented road or footpath, there is sufficient evidence of the existence of a nuisance which calls for removal. All foul privies, cesspools, and drains in rural districts can be dealt with under this clause. (3.) "Any animal so kept as to be a nuisance or injurious to health." This definition applies to pig-styes, fowl-pens, dog- kennels, cow-byres, etc. In dealing with nuisances of this description, it often happens that the abatement may 438 DUTIES OF MEDICAL OFFICERS OF HEALTH. be effected in various ways. For example, a nuisance arising from a pig-stye may be abated sometimes by keep- ing the animal in a more cleanly way, by lessening the number of pigs, by properly draining the pig-stye, by removing the pig-stye if it be too near a dwelling, or too near a frequented path, or by prohibiting the keeping of pigs altogether. It may safely be laid down as a rule, that pig-styes close to dwellings, or under bedroom win- dows, will always be more or less a nuisance, no matter how carefully the animal may be kept. (4.) " Any accumulation or deposit which is a nuis- ance or injurious to health." In this definition are included offensive manure-heaps, or other filth-accumulations, which are close to dwellings or frequented paths. It also applies to offensive refuse- heaps of every description, the only exception being made " in respect of any accumulation or deposit neces- sary for the effectual carrying on any business or manu- facture, if it be proved to the satisfaction of the Court that the accumulation or deposit has not been kept longer than is necessary for the purposes of the business or manu- facture, and that the best available means have been taken for preventing injury thereby to the public health." (5.) " Any house or part of a house so overcrowded as to be dangerous or injurious to the health of the in- mates, whether or not members of the same family." In previous parts of this work the necessity for an ample amount of cubic space for the requirements of per- fect health has been strongly insisted on an amount, however, which it is impossible to obtain or enforce in the dwellings of the poorer classes, and in common lodg- ing houses. Practically it is found that 300 cubic feet per head is the highest minimum which can be enforced in most large towns, and even that amount cannot be exacted in the case of many families consisting of husband DUTIES OF MEDICAL OFFICERS OF HEALTH. 439 and wife and young children. In rural districts also the difficulty of dealing with this form of nuisance on reason- able and equitable grounds is quite as great as it is in towns, if not greater ; and as an instance in point, I may quote the following remarks from one of my reports for 1874 : "In places where there is a scarcity of houses, it is evidently impossible to abate the nuisance to any extent, because in attempting to reduce the overcrowding in one part you only increase it elsewhere. But in Mid- Warwickshire this difficulty has not arisen, partly because the district is mainly agricultural and can only maintain a limited number of the labouring class, and partly, too, I have no doubt, because during the last two or three years there has been a considerable exodus from a good many of the villages in consequence of the agricultural labourers' movement. The cases of overcrowding met with have been generally confined to single families occupying houses with only one sleeping - room, and in endeavouring to deal with this form of nuisance there were several points which had to be considered. In the first place, it was clear that if the minimum allowance of cubical space per head was made too high, the instances of overcrowding, judged by this standard, would have become so numerous that any attempt to deal with them woidd have been impossible ; in the second place, the ages of the children had to be taken into account ; and in the third place, it became a question whether in con- demning a house as being too small for the family, another and suitable one was to be found in the village. With regard to cubical space, it appeared to me, after careful inquiry into the average amount of sleeping accommoda- tion, that the standard of 200 cubic feet per head was as high as it could be raised for families consisting of parents and young children, though at the same time I am free to confess that a minimum of 300 cubic feet space, even 440 DUTIES OF MEDICAL OFFICERS OF HEALTH. with good means of ventilation, is little enough for the requirements of health. But in cases where it was found that grown-up children of both sexes slept in the same room, or in the same room with their parents, the ques- tion of cubic space became a matter of secondary con- sideration, and the plea of overcrowding has been insisted on in the interests of decency as much as on the score of health. It will thus be seen that the cases of overcrowd- ing met with had to be decided according to the special circumstances of each rather than in accordance with any fixed rules, and though the minimum cubic space which has been adopted is small, it must be borne in mind that the dilapidated state of most of the cottages permits a freer interchange of air than is usually to be obtained in newer and better built houses. All this is, of course, an admission that only the more glaring cases of overcrowd- ing have been dealt with ; but with so many cottages containing only one sleeping-room, and taking into con- sideration the size of the rooms, it is impossible to lessen the extent of the evil except by acting on principles such as these. As it is, many cases of overcrowding have been abated, and the notices issued by the Inspectors have been so generally complied with that only a few cases had to be brought before the magistrates." (6.) "Any factory, workshop, or workplace (not already undei the operation of any general Act for the regulation of factories or bakehouses), not kept in a cleanly state, or not ventilated in such a manner as to render harmless, as far as practicable, any gases, vapours, dust, or other impurities generated in the course of the work carried on therein, that are a nuisance or injurious to health, or so overcrowded while work is carried on as to be dangerous or injurious to the health of those em- ployed therein." (See Chapter III.) (7.) " Any fireplace or furnace which does not, so far DUTIES OF MEDICAL OFFICERS OF HEALTH. 441 as practicable, consume the smoke arising from the com- bustible consumed therein, and which is used for work- ing engines by steam, or in any mill, factory, dyehouse, brewery, bakehouse, or gaswork, or in any manufacturing or trade process whatsoever ; and any chimney (not being the chimney of a private dwelling-house) sending forth black smoke in such quantity as to be a nuisance, shall be deemed to be nuisances liable to be dealt with sum- marily in manner provided by this Act ;" provided always that it can be shown that the best practical means have been adopted to consume the smoke, having regard to the manufacture or trade, and that due care has been exer- cised by the person in charge of the same. In order to obviate nuisances of this description, all furnaces or factory fireplaces should have chimneys of sufficient height, and should be provided with a smoke- consuming apparatus. Very often it is found that nuis- ance ^arises from neglect in stoking. 8. 0/ensive Trades (clauses 112-115). By these clauses power is given to urban sanitary authorities to restrict the establishment of offensive trades in their dis- tricts, such as bone-boiling, soap-boiling, tallow-melting, etc. ; to make by-laws with respect to the same ; and to direct complaint to be made before a Justice, if the effluvia given off are certified to be a nuisance or injurious to health, by the medical officer of health, or by two legally- qualified practitioners, or by any ten inhabitants of the district. Before a conviction can be obtained in respect to established trades, it will be necessary to prove to the satisfaction of the Court that the best practical means for the abatement of the nuisance have not been adopted ; and as the medical officer of health is liable, in most cases, to be called upon to give skilled evidence, it is necessary that he should be well acquainted with the process of manufacture, or the details of the trade complained of, the 442 DUTIES OF MEDICAL OFFICERS OF HEALTH. nature of the effluvia given off, and the best means which should be adopted to prevent nuisance. Such knowledge can, of course, only be obtained by inspecting offensive trades, and it must necessarily be supplemented by a thorough acquaintance with practical chemistry. Unless the medical officer of health is an expert in these matters, the best course to .pursue is to recommend the manufac- turer or tradesman, against whom complaint is made, to call in some competent person to advise him as to what steps he should take to prevent nuisance ; and in the event of no steps being taken, he should recommend the sanitary authority to consult an expert, who would give evidence before the magistrates if necessary. With proper precautions, the manufacturer of offensive products may, in the greater majority of instances, carry on his trade without causing serious nuisance to the neighbourhood, and not unfrequently finds it advantageous even as regards pecuniary interests when he is compelled to utilise his waste offensive refuse. Without entering into details, it may be said generally that all foul matters should be conveyed to the works in properly-constructed vans or tanks, which can be covered with tight-fitting lids, and that they should be stored in closed chambers or tanks, ventilated, if necessary, into the furnace fires, or to special scrubbers. All foul processes, such as oil-boiling, tallow-melting, and the like, should be carried on in boilers with tight-fitting lids ; and the effluvia given off should be conducted first to a condenser to get rid of the steam, if necessary, and then to the furnace-fire to be consumed. The sulphuretted hydrogen and ammonium compounds which are given off in the manufacture of salts of ammonia from gas-liquor, should also be conducted from the vats to the furnace-fire to be burnt. Again, all gases and vapours which can be condensed! or absorbed should be passed through condensers or absorbents speci- DUTIES OF MEDICAL OFFICERS OF HEALTH. 443 ally suited for them, as, for example, water in the form of spray, or scrubbers charged with water, sulphuric acid, or alkaline solutions. In Dr. Ballard's valuable report concerning offensive trades, already referred to in Chapter III., he thus classi- fies the ordinary sources of origin of effluvium nuisances: "1. Accumulation of filth on or about the business premises, or on its removal from the premises in an offensive condition. " 2. A generally filthy condition of the interior of the buildings and the premises and utensils generally. " 3. An improper mode of disposing of offensive refuse, liquid or otherwise. " 4. Insufficient and careless arrangements in the reception of offensive materials of the trade, or in the removal of offensive products either from the premises, or from one part of the premises to another. " 5. An improper mode of storing offensive material or offensive products within the works. "6. The escape of offensive gases or vapours given off during some part or parts of the processes to which the materials of the trade are subjected into the atmosphere outside the works." The report contains abundant illustrations of the modes in which effluvium nuisances may arise from busi- ness premises, and is replete with information concerning methods in use, or which may be devised to obviate or minimise them ; but without referring to particular trades it will be sufficient to indicate the general principles on which prevention should be based, and these are laid down by Dr. Ballard as follows : " As respects the first and second of these sources of effluvium nuisances, the obvious remedy is ' cleanliness ' in the broadest sense of the word. " 1. Filth should be removed from the premises speedily in the impervious covered vessels in which it ought always to be collected from time to time during the day. "2. Those parts of the interior of premises liable to become dirty or encrusted with filth or decomposable matter, and all the ntuiisils employed, should be regularly cleansed. Such structural and working arrangements should be made as shall not only tend to prevent such defilements, but also tend to facilitate cleansing. 444 DUTIES OF MEDICAL OFFICERS OF HEALTH. " 3. Solid refuse should be separated from liquid refuse as far as practicable, and each should be disposed of in its appropriate manner, the solids being deposited and speedily removed in covered impervious vessels, and the liquids being run off into proper drains in such a condition as not necessarily to give rise to offensive emana- tions. Deodorants may sometimes be used with advantage. 11 4. Offensive matters necessary for use in the business should be brought upon the premises either in covered impervious vessels, or covered up in such a manner that they shall not be a source of effluvium-nuisance in transit. They should be so received in an enclosed building, and unloaded with due precaution against the issue of effluvia in the process. Offensive products should be re- moved similarly from the premises. Precautions should also be used in the removal of offensive products from one part of the pre- mises to another. Difficulties in this respect now and then arise in works from insufficient space, or bad arrangements of workshops and receptacles. In such cases as these, modifications may be necessary in the works themselves. " 5. Offensive materials and products of the business should either be stored in impervious vessels or in a close chamber, venti- lated, if necessary, in such manner that the effluvia shall not become a nuisance. " 6. Sometimes a careful selection of the materials of the manu- facture, or some little modification of the manner of conducting a part of the process, may be sufficient to obviate an effluvium nuisance wholly or partially. But when the evolution of offensive gases or vapours is not thus avoidable, they must be intercepted in their passage to the external air, and dealt with in such a manner as to destroy their offensive character. One method of interception con- sists in arrangements for drawing off in a continuous manner the air of the entire chamber or workshop in which the offensive effluvia are evolved ; but mostly the interception is practicable without doing this. When drawn off or collected, they may, according to their nature, be dealt with in one of five ways : (1.) They may be discharged into the atmosphere at such an elevation as that they shall be so diluted before reaching the ground as not to be offensive. When this will not suffice, other means must be used. (2.) If the evolved matters be condensible by cold, they may be passed through an appropriate condensing apparatus. (3.) If soluble in water, they may be sub- mitted to the action of water in an appropriate apparatus, or simi- larly, to the action of any other liquid better calculated to absorb them. (4.) Sometimes, in like manner, solid substances, with which the effluvia have chemical affinity, may be used with advantage, either in powder or otherwise. (5.) If the evolved matters be com- DUTIES OF MEDICAL OFFICERS OF HEALTH. 445 bustible, they may be burned by conducting them through a fire." (Supplement to Local Government Board Report, 1876.) 9. Unsound Meat, etc. (clauses 116-119). These clauses empower the medical officer of health or inspector of nuisances to inspect and examine, at all reasonable times, " any animal, carcase, meat, poultry, game, flesh, fish, fruit, vegetables, corn, bread, flour, or milk, exposed for sale, or deposited in any place for the purpose of sale, or of preparation for sale, and intended for the food of man." In carrying out his duties in this respect, it is advis- able that the medical officer of health, when he is not called in by the sanitary inspector, should get that officer, or failing him a policeman, to seize the condemned articles in order to have them dealt with by a Justice. The onus of proving that the article seized was not ex- posed or deposited for sale, or for preparation for sale, or was not intended for the food of man, rests upon the person charged. Very often, with regard to bad meat, the defence set up is that the article seized was not in- tended for the food of man, but for feeding dogs, or to be boiled down with other offal as the case may be. So far, however, as the medical officer of health is concerned, he should endeavour, as far as possible, to confine his evi- dence to the question as to whether the article seized is or is not fit for the food of man, leaving the rest of the evidence to be given by the sanitary inspector or other witnesses. Various practical hints concerning the ex- amination of different articles of food have already been given in Chapter II., while medical officers of health, who are also appointed as public analysts under the " Sale of Food and Drugs Act, 1875," must be specially qualified. 10. Infectious Diseases? Hospitals, Morticaries, etc. (clauses 120-143). This part of the subject has already been so fully discussed in previous chapters that little more remains to be said. The medical officer of health 446 DUTIES OF MEDICAL OFFICERS OF HEALTH. will have to consider whether, in the event of an outbreak of epidemic disease occurring in his district, there can be procured at short notice sufficient means of isolation. It is true that in some rural districts the population is so very scattered that hospital accommodation is not re- quired, because sufficiently protective measures can be adopted by quarantining, as far as possible, any infected houses, and by supplying properly trained nurses, if they should be wanted, who may be paid either by the sanitary authority, or, in the case of paupers, by the board of guardians. When an outbreak threatens to be serious, a strict watch should be kept on all houses where infectious disease is known to exist, and there should be no hesita- tion in summoning any one who wilfully or carelessly offends against any of the clauses of the Act. In order that there may be no excuse for pleading ignorance in this respect, the sanitary inspector should be supplied with placards containing the necessary precautions to be taken (see Appendix), a copy of which he should leave at every infected house. In inquiring into the origin of any outbreak, or in giving instructions with regard to pre- venting its spread, it need hardly be said that the medical officer of health should be very careful not to examine any case without first requesting the sanction of the medical attendant, and unless he has reason to believe that an error has been made in the diagnosis, he should never question the accuracy of any returns which may be made to him. He will also have to consider whether it is necessary that any schools should be closed, and in recommending that such a step should be taken, he should always give a certificate in the case of public elementary schools, in order that the teacher may not be deprived of the government grant which is allowed on the average attendance of the pupils. According to a recent code issued by the Education Department, it is made incumbent DUTIES OF MEDICAL OFFICERS OF HEALTH. 447 on the managers of all such schools to close them for a stated time by order of the sanitary authority, on receipt of the necessary certificate from the medical officer of health. With regard to the special provisions of this section of the Act, it may be pointed out that it is imposed as a duty on all sanitary authorities to cause premises to be cleansed or disinfected, and they are further empowered to direct the destruction of any bedding, clothing, or other articles, which cannot otherwise be safely disinfected, and to pay for the same ; to supply means of disinfection if necessary ; and to provide ambulances, hospitals, and mor- tuaries. They may either build such hospitals or places of reception, or contract for the use of any such hospital, or part of a hospital, or place of reception ; or enter into any agreement with any person having the management of any such hospital; or two or more authorities may combine in providing a common hospital. In populous districts, it is always advisable that a proper hospital should be erected ; and in small urban and rural districts, it will often be found that such hospital accommodation can be most economically and efficiently provided by combination of neighbouring authorities. The term place of reception will include any house which may be rented for the reception of infectious cases, or any hut or tent, or, in the case of seaport towns, any hospital ship. Clause 132 empowers a sanitary authority to recover the cost of maintenance of any patient who is treated in any such hospital, who is not a pauper ; but inasmuch as the removal of a patient to a hospital may be said to confer as great a benefit on the public as it does on the patient, the enforcement of payment would not only be manifestly unfair in many cases, but would tend greatly to diminish the usefulness of such hospital. According to clause 124 the only persons who can be removed to an infectious hospital by order of a justice, on a certifi- 448 DUTIES OF MEDICAL OFFICERS OF HEALTH. cate signed by a legally qualified practitioner, are the fol- lowing : Any person who is suffering from any dangerous infectious disorder, who is without proper lodging or ac- commodation, or lodged in a room occupied by more than one family, or is on board any ship or vessel; or any person so suffering who is lodged in any common lodging- house. With proper tact, however, on the part of the medical officer of health in enlisting the co-operation of medical attendants, and readiness on the part of the sani- tary authority to attend to his recommendations, there will generally be little difficulty experienced in inducing most patients to enter the hospital who are fit to be re- moved, and whose removal is considered advisable for the public safety. Although the sanitary protection afforded by hos- pitals, mortuaries, disinfecting apparatus, and the like, is now placed beyond dispute, it unfortunately happens that sanitary authorities, as a rule, are very slow to exercise the powers vested in them in this respect, unless under the pressure of an epidemic, and consequently the recom- mendations of the medical officer of health to be prepared beforehand are often thrown aside. But this need not discourage or annoy him in any way. His plain duty is to study carefully the requirements of his district, and having done this to submit his views as clearly and as concisely as he can to the sanitary authority, using the best arguments he can advance to support his case, show- ing every readiness to answer any questions, and being fully prepared to meet any objections. If his recommen- dations are not complied with, the onus will rest on the sanitary authority, and not on him ; but at the same time he should be careful to bring them forward on some future occasion, when very likely they will either meet with acceptance, or at all events some efforts will probably be made to carry them out. DUTIES OF MEDICAL OFFICERS OF HEALTH. 449 Clauses 134 to 140 empower the Local Government Board, whenever any formidable outbreak takes place in any part of England, to make regulations for the speedy interment of the dead, for house-to-house visitation, for medical aid and accommodation, and for other means to prevent the spread of disease ; but it will only be in cases of the gravest emergency, and when the health of his district is seriously endangered, that the medical officer of health will feel it incumbent on him to recommend the enforcement of these clauses. In all cases of infectious disease, care should be taken to ensure as far as possible the right use of disinfectants, and it is always a wise economy on the part of sanitary authorities to supply disinfectants gratuitously to those who are too poor to buy them. Moreover, as it is the duty of the sanitary authority to take care that disinfec- tion is efficiently carried out, the sanitary inspector, under the direction of the medical officer of health, should him- self superintend or assist in the process of the disinfection of rooms, etc., or in populous districts some one should be specially appointed to act as a disinfector. For detailed information with regard to hospitals, infectious disease, etc., see Chapters X. and XIV., and Appendix. 11. The other clauses in the Public Health Act which are of special interest to the medical officer of health are the following, and they apply exclusively to urban dis- tricts, or districts provided with urban powers : Clause 157 gives power to make by-laws respecting new buildings, etc. Clause 164 empowers an urban sanitary authority to provide places of public recreation. clause 166 gives power to provide markets. Clauses 169-170 give power to provide public slaugh- ter-houses, and to regulate private slaughter-houses. 2 G 450 DUTIES OF MEDICAL OFFICERS OF HEALTH. In Schedule IV. of the Act will be found the various legal forms of notice for requiring the abatement of nuis- ance, summons, etc., but these concern the clerk and. sanitary inspector more than they do the medical officer of health. 12. The other Acts which have not been repealed by the Public Health Act, to which reference may be made, are the Artisans' and Labourers' Dwellings Act, the Bakehouse Eegulation Act, and the Baths and Wash- houses Act, but as the essential provisions of these are included in the by-laws of all urban districts in which they are in force, they need not be further considered here. In towns" containing a population of 25,000 and up- wards, as enumerated at the last census, an important duty will devolve upon the medical officer of health of recommending the adoption of the Artisans' Dwellings Acts of 1875, when any houses, courts, or alleys, within a certain area of his district, are unfit for habitation by reason of their unhealthiness, and when the sanitary defects in such area cannot be effectually remedied other- wise than by an improvement scheme. As the local authority cannot carry out the intentions of the Act with- out an official representation made by the medical officer of health, and as he is bound by the Act to make such representation whenever he sees cause for the same, it need hardly be said that the duty imposed upon him will demand the utmost care and conscientiousness on his part. The provisions of the Public Health (Water) Act have already been referred to, and the only other Acts with which the medical officer of health should make himself familiar are the Sale of Food and Drugs Act, 18*75, and the Canal Boats Act, 1877. The latter Act empowers the Local Government Board to appoint sani- DUTIES OF MEDICAL OFFICERS OF HEALTH. 451 tary authorities having districts abutting on a canal as registration authorities to register boats and number them, and to fix the number, age, and sex of the persons who may be allowed to dwell in each boat. Eegulations are also provided for the separation of the sexes, cleanli- ness, ventilation, habitable condition, and for preventing the spread of infectious diseases. 13. By -Laws. In all urban districts, the medical officer of health will find that by-laws have already been framed, and as a matter of course he should at once make himself thoroughly acquainted with their details, and more especially with those which relate to the removal of refuse and the prevention of nuisance, the sanitary arrange- ments of new buildings, and the inspection and regulation of slaughter-houses, bakehouses, and common lodging- houses. Unfortunately, rural sanitary authorities have no power to issue by-laws with respect to new buildings, etc., unless they are provided with urban powers ; but since these can be granted by the Local Government Board, it will become the duty of the medical officer of health to recommend that an application be made for the granting of such powers, whenever he feels assured that the sanitary requirements of his district demand them. In order that he may be fully qualified to advise the sani- tary authority with regard to the framing of by-laws when required, the medical officer of health should make himself thoroughly acquainted with the code of model by-laws which have been issued by the Local Govern- ment Board. 14. Legal Proceedings. Unless under exceptional circumstances, the medical officer of health should never conduct a case before the Justices, that is the duty of the clerk to the sanitary authority, or in respect to com- mon nuisances, it is often discharged by the sanitary in- spector. Although he will often have to recommend that 452 DUTIES OF MEDICAL OFFICERS OF HEALTH. proceedings be taken, his duty, so far as the prosecution is concerned, should be confined to furnishing a certificate or giving evidence when required. With a well-trained inspector, it is seldom that he will be required to give evidence except as regards cases of overcrowding, infected houses, or exposure of infected persons, clothing, etc., unsound meat, nuisances which are likely to be contested, and offensive trades. 15. Routine of Duty. This of course will very much depend on the nature and extent of the district. It unfortunately happens that in many instances the appointment of medical officer of health is made under circumstances in which he is expected to do but little, and that little only when called upon by the sanitary inspector to certify or give evidence. But in all large urban or combined districts, it is necessary that the duties should be carried on as systematically as possible. As already stated, the sanitary inspector or inspectors should be under the supervision of the medical officer of health, and any orders from the sanitary authority affecting the duties of these officials should be conveyed through him or with his concurrence, otherwise he cannot be held responsible for the efficient working of his department. The following are the duties of the sanitary inspector as laid down by an order of the Local Government Board, dated November 11, 1872, and they apply to all in- spectors who are appointed subject to the approval of that Board : " The following shall be the duties of the inspector of nuisances in respect of the district for which he is appointed, or if he shall be appointed for more than one district, then in respect of each of such districts : *"(!.) He shall perform, either under the special directions of the sanitary authority, or (so far as authorised by the sanitary authority) under the directions of the medical officer of health, or in cases where no such directions DUTIES OF MEDICAL OFFICERS OF HEALTH. 453 are required, without such directions, all the duties specially imposed upon an inspector of nuisances by the Sanitary Acts, or by the orders of the Local Govern- ment Board. "(2.) He shall attend all meetings of the sanitary authority when so required. "(3.) He shall by inspection of the district, both systematically at certain periods, and at intervals as occasion may require, keep himself informed in respect of the nuis- ances existing therein that require abatement under the Sanitary Acts. " (4.) On receiving notice of the existence of any nuisance within the district, or of the breach of any bye-laws or regula- tions made by the sanitary authority for the suppres- sion of nuisances, he shall, as early as practicable, visit the spot, and inquire into such alleged nuisance or breach of bye-laws or regulations. " (5.) He shall report to the sanitary authority any noxious or offensive businesses, trades, or manufactories established within the district, and the breach or non-observance of any bye-laws or regulations made in respect of the same. " (6.) He shall report to the sanitary authority any damage done to any works of water-supply, or other works belonging to them, and also any case of wilful or negligent 'waste of water supplied by them, or any fouling, by gas, filth, or otherwise, of water used for domestic purposes. "(7.) He shall from time to time, and forthwith upon com- plaint, visit and inspect the shops and places kept or used for the sale of butchers' meat, poultry, fish, fruit, vegetables, corn, bread, or flour, or as a slaughter-house, and examine any animal, carcase, meat, poultry, game, flesh, fish, fruit, vegetables, corn, bread, or flour, which may be therein ; and in case any such article appear to him to be intended for the food of man, and to be unfit for such food, he shall cause the same to be seized ; and take such other proceedings as may be necessary iii order to have the same dealt with by a justice : Provided that in any case of doubt arising under this clause he shall report the matter to the medical officer of health, with the view of obtaining his advice thereon. " (8.) He shall, when and as directed by the sanitary authority, procure and submit samples of food or drink, and drugs -uspected to be adulterated, to be analysed by the 454 DUTIES OF MEDICAL OFFICERS OF HEALTH. analyst appointed under the Adulteration of Food Act, 1872 ; and upon receiving a certificate stating that the articles of food or drink, or drugs, are adulterated, cause a complaint to be made, and take the other pro- ceedings prescribed by that Act. " (9.) He shall give immediate notice to the medical officer of health of the occurrence within his district of any con- tagious, infectious, or epidemic disease of a dangerous character ; and whenever it appears to him that the intervention of such officer is necessary in consequence of the existence of any nuisance injurious to health, or of any overcrowding in a house, he shall forthwith in- form the medical officer thereof. " (10.) He shall, subject in all respects to the directions of the sanitary authority, attend to the instructions of the medical officer of health with respect to any measures which can be lawfully taken by him under the Sanitary Acts for preventing the spread of any contagious, in- fectious, or epidemic disease of a dangerous character. " (11.) He shall enter from day to day, in a book to be provided by the sanitary authority, particulars of his inspections and of the action taken by him in the execution of his duties. He shall also keep a book or books, to be pro- vided by the sanitary authority, so arranged as to form, as far as possible, a continuous record of the sanitary condition of each of the premises in respect of which any action has been taken under the sanitary Acts, and shall keep any other systematic records that the sanitary authority may require. " (12.) He shall at all reasonable times, when applied to by the medical officer of health, produce to him his books, or any of them, and render to him such information as he may be able to furnish with respect to any matter to which the duties of inspector of nuisances relate. " (13.) He shall, if directed by the sanitary authority to do so, superintend and see to the due execution of all works which may be undertaken under their direction for the suppression or removal of nuisances within the district. "f 14.) In matters not specifically provided for in this order, he shall observe and execute all the lawful orders and directions of the sanitary authority, and the orders of the Local Government Board which may be hereafter issued, applicable to his office." DUTIES OF MEDICAL OFFICERS OF HEALTH. 455 In some valuable articles which appeared in the Medical Times and Gazette in Nov. 1872, on the duties of medical officers of health, the following sketch of the daily routine in a large metropolitan parish is given as a guide for commencing health officers : " At 9 A.M. the subordinate officers arrive at the office. They consist of a clerk, a messenger (who is always a copying clerk), the sanitary inspectors, to each of whom a district is assigned, and a disinfector. Shortly after the medical officer arrives, reads his letters, confers with the clerk, gives directions as to the correspond- ence of the day, receives verbal reports from the inspectors as to the previous day's work, and makes appointments for these officers to meet him at particular places during the course of the day, should his presence be deemed necessary in particular cases. In a few minutes a large amount of routine work can thus be got through, whilst reports for committees, special correspondence, and the ex- amination of the books of the department, can be despatched, say twice or thrice a week, at any convenient time. Between 9 and 10 A.M. each inspector writes out a brief diary of his previous day's work for the information of the medical officer, and instructs the disinfector as to houses where disinfection is required. At 10 the sanitary inspectors depart on their daily rounds, having previously informed themselves as to any new complaints requiring their atten- tion. After their departure the clerk extracts and summarises their diaries, and enters the results in the proper books. The books actually in use are (1.) The medical officer's diary, in which he briefly enters the dates of visits made, with any particulars he thinks fit. (2.) A book for receiving the complaints of ratepayers and others. (3.) A record of houses in which infectious disease has appeared. (4.) The diaries of the several sanitary inspectors. (5.) A book recording the progress of works, which exhibits at a glance the visits made and the works executed at any particular house. From this the clerk extracts, and presents weekly to the medical officer (6.) A list of works in arrear. (7.) A report book in which the health officer reports to the sanitary committee all ordinary cases of nuisances uncompleted, together with his recommendations. Further, the sanitary inspector:; are provided with forms of notices of nuisances, arranged in books with duplicates, after the manner of a cheque-book. These arrangements may seem complicated. In practice, however, they are found to be simple arid effective. Where little or no clerical assistance is furnished, they may be much simplified, and the books reduced in number." 456 DUTIES OF MEDICAL OFFICERS OF HEALTH. In small urban or rural districts, and in combined districts when special clerical assistance is not required, the only book which it may be necessary to keep beyond filing statistics, reports, and any important official com- munications, is a diary, but this should always be kept, no matter how meagre the duties may be, because it will be frequently required for reference. 16. Eeports. All reports from the health officer to the sanitary authority should be concise and to the point. The stated reports, weekly, quarterly, or otherwise, will deal chiefly with the vital statistics of the district, and enumerate such proceedings as have been undertaken, according to the provisions of the Sanitary Acts, together with any suggestions which he may deem it to be his duty to lay before the sanitary authority from time to time. He should avoid entering into lengthy disquisitions, because he will have the opportunity, at meetings of the sanitary authority, of answering any questions, and justify- ing his recommendations, should he be called upon to do so. As far as possible he should base his stated reports on a uniform plan, and he may be quite ,sure that the briefer they are in their completeness, the more they will be appreciated. Annual reports should embrace all the points indicated in the regulations of the Local Govern- ment Board, previously quoted. (For official instructions see Appendix.) If his reports appear in the public newspapers of the district, as will generally be the case, he should endeavour, without being diffuse, to make them readable and instruc- tive, and whenever he considers it necessary to address the public through this channel, with respect to any sanitary dangers to which they may be specially exposed, it is always advisable that his remarks should, in the first instance, be submitted to the sanitary authority. Although he will find the press to be of great assistance in educating DUTIES OF MEDICAL OFFICERS OF HEALTH. 457 the public in sanitary matters, it need hardly be said that he should avoid entering into controversy, and that he should be very careful not to drag the names of private individuals before the public when his reports are printed. 17. Official Conduct. With regard to his subordinates, the medical officer should endeavour to arouse in them an esprit de corps, not doing their work, but seeing that they do it themselves efficiently and readily. He should listen courteously to any remarks or suggestions which they may make, and if they are trained officers, give them credit for knowing their duties as well as he does his own. In their own sphere they are as sensitive to rebuke as him- self, and it should, therefore, never be administered unless it is merited. Any serious delinquency or inefficiency on their part should be laid before the sanitary authority, and those who do perform their duties satisfactorily should be as frankly commended. Above all, punctuality should be insisted on. In cases where the health officer will have to educate sanitary inspectors who are new to the work, it would be desirable that all candidates for stich an important post should pass a certain period of probation before their appointment is confirmed by the sanitary authority. As regards the portion of the community committed to his charge, he should endeavour, conscientiously and to the best of his ability, to fulfil his obligations towards them, and if in practice, he should in no wise shirk his public duty, even at the risk of losing his best patient. In this, as in all other affairs of life and conduct, it will be found that in the long run " honesty is the best policy." Towards his medical brethren he should religiously observe the ethics of his profession, and act up to the golden rule, " Do to others as you would be done by." He should endeavour to be on friendly terms with all within his district, and never hesitate to court their assist- ance and advice when he feels that he may require them 458 DUTIES OF MEDICAL OFFICERS OF HEALTH. in the discharge of his duties. It need hardly be said that all such favours or obligations should be readily and ungrudgingly reciprocated on his part. If he is not de- barred from private practice, he should be careful, above all things, not to take advantage of his public office by using it as a means to increase the number of his patients. This, to say the least, would be a grave breach of profes- sional etiquette, which would deservedly arouse remon- strance and opposition on the part of his medical brethren. His relations to the sanitary authority or sanitary committee, as the case may be, should be guided by common sense and a sense of duty. He should always remember that he is their medical adviser, not their dic- tator ; and at their meetings he should carefully avoid taking part in discussions on his reports, unless called upon to do so, or in reply to objections. He should at- tend all meetings at which his presence is requested or expected ; and when he does attend, he should support his views, when called upon, with clearness, firmness, courtesy, and tact. His proposals may be rejected, but if they do not lie within the scope of the statutory enact- ments requiring their enforcement, he should never resent opposition, but again bring them forward on future occa- sions. But with regard to breaches of sanitary law, which in spite of his representations may be persistently ignored, he should unhesitatingly insist upon their being remedied, and, failing action, he can always appeal to the Local Government Board. It is to be hoped, however, that he will seldom meet with such unwarrantable opposition. Under all circumstances he should strive to exercise a wise forbearance when he can conscientiously do so, and on all occasions maintain a courteous, dignified, and friendly demeanour towards the sanitary authority, feeling assured that tact and good temper, like good words, " are worth much, and cost but little." APPENDIX. OFFICIAL MEMORANDA AND OTHER DATA. I. The DAIRIES, COW-SHEDS, and MILK-SHOPS ORDER of 1879, issued 4th February 1879. 1. Preliminary. This Order may be cited as The Dairies, Cow- Sheds, and Milk-Shops Order of 1879. 2. This Order shall take effect from and immediately after the making thereof. 3. This Order extends to Great Britain only. 4. In this Order The Act of 1878 means The Contagious Diseases (Animals) Act, 1878; Other terms have the same meaning as in the Act of 1878. 5. Registration of Cow -Keepers and others. (1.) Every Local Authority shall, with all practicable speed after the making of this Order, open, and shall thenceforth keep, a register for the registra- tion with them under this Order of all persons from time to time currying on in their district the trade of cow-keepers, dairymen, or purveyors of milk, and shall, from time to time, revise and correct the register. (2.) The Local Authority shall give public notice, by advertise- ment in a newspaper circulating in their district, and, if they think fit, by placards, handbills, or otherwise, of the time at which the register will be opened, and of the mode of registration. (3.) After the expiration of the time prescribed in this behalf in the advertisement, not being more than two months, and not being leefl than fourteen days, from the publication of the advertisement, it shall not be lawful for any person to cany on in the district of the Local Authority the trade of a cow-keeper, dairyman, or pur- veyor of milk, unless he is registered as such under this Order. 6. Dairies and Coio-Sheds. It shall not be lawful for any person 460 APPENDIX. following the trade of cow-keeper or dairyman to begin to occupy as a dairy or cow-shed any building not so occupied at the making of this Order, unless and until he first makes provision, to the reason- able satisfaction of the Local Authority, for the lighting, ventilation, cleansing, drainage, and water-supply, of the same, while occupied as a dairy or cow-shed. 7. It shall not be lawful for any person following the trade of cow-keeper or dairyman to occupy as a dairy or cow-shed any build- ing, whether so occupied at the making of this Order or not, if and as long as the lighting, ventilation, cleansing, drainage, and water- supply thereof are not such as are necessary or proper (a.) for the health and good condition of the cattle therein ; and (&.) for the cleanliness of milk-vessels used therein for contain- ing milk for sale ; and (c.) for the protection of the milk therein against infection and contamination . 8. Cleansing. A Local Authority may, from time to time, make regulations for prescribing and regulating the cleansing of dairies and cow-sheds in the occupation of persons following the trade of cow-keepers or dairymen, and the cleansing of milk-stores, milk- shops, and milk-vessels used for containing milk for sale by such persons. 9. Contamination of Milk. If at any time disease exists among the cattle in a dairy or cow-shed, or other building or place, the milk of a diseased cow therein (a.) shall not be mixed with other milk ; and (6.) shall not be sold or used for human food ; and (c.) shall not be sold or used for food of swine or other animals, unless and until it has been boiled. 10. It shall not be lawful for any person following the trade of cow-keeper, or dairyman, or purveyor of milk, or being the occupier of a milk-store or milk-shop, to allow any person suffering from a dangerous infectious disorder, or having recently been in contact with a person so suffering, to milk cows, or to handle vessels used for containing milk for sale, or in any way to take part or assist in the conduct of the trade or business of the cow-keeper, dairyman, purveyor of milk, or occupier of the milk-store or milk-shop, as far as regards the production, distribution, or storage of milk, until all danger therefrom of the commtfnication of infection to the milk, or of its contamination, has ceased. 11. It shall not be lawful for a person following the trade of cow-keeper, or dairyman, or purveyor of milk, or being the occupier of a milk-store or milk-shop, to use a milk-store or milk-shop in his occupation, or permit the same to be used, for any purpose incom- APPENDIX. 461 patible with the proper preservation of the cleanliness of the milk- store or milk-shop, and of the milk-vessels and milk therein, or in any manner likely to cause contamination of the milk therein. C. L. PEEL. II. MEMORANDUM on HOSPITAL ACCOMMODATION, to be given by LOCAL AUTHORITIES. (See Chap. X.) III. AMBULANCES. For the conveyance to hospital of patients who are sick with in- fectious disease, special carriages, which are known by the name of " ambulances," are necessary. Such carriages may be provided by sanitary authorities under 24 of the Sanitary Act, 1866. 1 The following points have to be attended to in the provision and use of such carriages : 1. If the ambulance be intended only for journeys of not more than a mile, it may be made so as to be carried between two people, or it may be on wheels and to be drawn by hand. If the distance be above a mile, the ambulance should be drawn by a horse. Every ambulance on wheels should have easy carriage-springs. 2. In the construction of an ambulance, special regard should be had to the fact that after each use it has to be cleansed and dis- infected. The entire interior, and the bed-frame and bed, should be of materials that can be washed. 3. The ambulance should be such that the patient can lie full length in it ; and the bed-frame and bed should be movable, so that the patient can be arranged upon the bed before being taken out of his house. 4. With an ambulance there should always be a person specially in charge of the patient ; and a horse-ambulance should have a seat for such person inside the carriage. 5. After every use of an ambulance for infectious disease, it should be cleansed and disinfected to the satisfaction of a medical officer. 6. Both in very populous districts, and in districts which are of very wide area, it may often happen that more than one ambulance will be wanted at one time ; and, in any district, if more than one infectious disease is prevailing, there will be an evident sanitary advantage in having more than one ambulance for use. JOHN SIMON. Medical Department of the Local Government Board, December 1874. 1 123 of the Public Health Act, 1875. 462 APPENDIX. IV. RULES drawn up by the AUTHOR for the SOLIHULL HOSPITAL for INFECTIOUS DISEASES. KULES TOR MEDICAL OFFICER, MASTER, AND MATRON. 1. The Medical Officer shall be the responsible head of the establishment, and shall visit occasionally, even when there are no patients, to assure himself that the master and matron are attending to their duties. 2. It shall be the duty of the master and matron to keep the wards scrupulously clean, and to have the bedding well aired and in readiness at all times for the reception of patients. They shall keep an inventory of everything belonging to the hospital, and a careful record of the articles of food and drink supplied to patients by the order of the medical officer or other medical attendant. One of them shall always be at the hospital, unless when special leave is granted by the sanitary authority or their clerk. They shall obey the instructions of the medical officer, and be responsible for the good conduct of nurses and patients. 3. The master shall attend the board meetings at Solihull at least once a month, to submit his books and take orders for neces- saries. RULES FOR PATIENTS AND FRIENDS. 1. No person shall be admitted to the hospital without the pro- duction of a certificate signed by a duly qualified medical practi- tioner. 2. Any patient admitted into the hospital may be attended by any qualified medical practitioner, provided that a request to this effect is submitted to the medical officer or sanitary inspector at the time of admission, and that the cost of such attendance is defrayed by the patient or friends. 3. No visitor shall be allowed inside the building or grounds without written permission from the medical officer. 4. No patient shall leave the wards or take exercise in the grounds without permission from the medical officer or medical attendant. 5. Any patient leaving the hospital, without the written per- mission of the medical officer or medical attendant, will be liable to heavy penalties, which will be enforced by the sanitary authority. 6. No patient shall leave the hospital without a change of clothes, unless the clothing used during convalescence has been carefully disinfected. APPENDIX. 463 7. No person in attendance upon patients shall leave the hos- pital without permission from the medical officer, nor without a change of clothes. V. MEMORANDUM on the STEPS specially requisite to be taken by BOARDS of GUARDIANS under the VACCINA- TION ACTS 1867 and 1871, in places in which SMALL- POX is EPIDEMIC. As it is by vaccination that the spread of smallpox can most effectually be prevented, Boards of Guardians, as soon as any case of that disease is brought into or occurs in their respective Unions or Parishes, should see that measures are promptly taken to secure, as far as necessary, the vaccination (or, as the case may be, re- vaccination) of all such persons as are especially exposed to the danger of the infection. Under the Order of Privy Council of February 18, 1868 (Eeg. I. Art. 1), the public vaccinator is authorised to vaccinate, elsewhere than at the public station, cases in which there exists a special reason (to be noted by him in his register) for taking this excep- tional course ; and sec. 13 of 34 and 35 Viet. cap. 98, provides that district medical officers in attendance upon any person suffer- ing from smallpox shall be entitled to payment from the Guardians for vaccinating or (as the case may be) re-vaccinating any person who is resident in the same house as such sick person, and who could lawfully be vaccinated or (as the case may be) re-vaccinated by a public vaccinator at the public expense. These provisions, promptly applied on the occurrence of any isolated case or cases of smallpox, will in general be found adequate to stop the further spread of the disease ; but if from neglect of them or from any other circumstances cases of smallpox shall have become numerous, special measures (as below explained) should be taken to expedite, as far as practicable, the vaccination of all un- vaccinated persons in the district, and to promote the re- vaccination of adults and adolescents who have not already been successfully re-vaccinated ; and special arrangements (as below explained) may also be requisite to facilitate the performance of public vaccination and re-vaccination. This Memorandum is intended to afford information on those measures and arrangements. I. Special Instructions to Vaccination Officers. 1. At times when smallpox is epidemic, the vaccination officer 464 APPENDIX. should give his first and special attention to the particular localities in which the infection exists. 2. In order that for this purpose he may have the earliest pos- sible information of the occurrence of cases of the disease, the Guardians should instruct their district medical officers to give him immediate notice of every fresh case of smallpox which comes under their treatment, and should also arrange with the registrars of deaths to forward to him immediate notice of each death registered from smallpox. For convenience of transmitting such< notices, each district medical officer and Registrar should be supplied with forms duly stamped for post, or with post-cards adapted for the purpose. Private medical practitioners should also be invited to give similar information. 3. In each locality in which the infection exists, the vaccination officer should with the utmost possible despatch personally ascertain what children are unprotected by vaccination, and should use his utmost exertions to obtain the prompt vaccination of all such children. Generally speaking, his own judgment and local know- ledge will guide him as to the manner in which his inquiries can best be made ; but in infected courts or alleys, as well as certain kinds of streets, inquiries from house to house, and in tenement- houses from room to room, will be indispensable. 4. Where any child (between the ages of 3 months and 14 years) is found illegally unvaccinated, the vaccination officer should give a notice requiring the vaccination to be done within a specified period. This period, when there is smallpox in the house, or other special risk of exposure to the contagion, should not exceed twenty- four hours ; but in other cases some days, not exceeding a week, may be allowed. A second visit from the vaccination officer will, of course, afterwards be necessary in order to see that his notice has been complied with. With regard to unvaccinated children not yet three months old, who may be in infected localities, the vaccination officer should advise the parents not to incur the unnecessary risk of waiting for the child to complete that age before having its vaccination per- formed ; for vaccination is perfectly well borne by children even immediately after birth. In no house in which there is smallpox ought a child, however young, on any account to remain unvacci- nated, unless on medical examination it be pronounced unfit to be vaccinated. 5. The vaccination officer should make it well known in infected localities that the public vaccinator is at liberty to re-vaccinate grown-up and young persons (not under 12 years of age) who have not before been successfully re- vaccinated, and who apply to him APPENDIX. 465 for that purpose ; and that persons not vaccinated since childhood, who are likely to be exposed to contagion, ought to be re- vaccinated without delay. Above all, this is necessary for persons whose" original marks of vaccination are imperfect 6. All notices given and representations made as above should be accompanied with information as to the provisions made for public vaccination in the district. If any case requiring prompt vaccination by the public vaccinator cannot, in the judgment of the vaccination officer, properly be taken to the station or to the resi- dence of the public vaccinator, the vaccination officer should give to the public vaccinator immediate information of the case. 7. Besides the above-described special proceedings in localities already infected, the vaccination officer should take every means to ensure that the vaccination of his district generally is as complete M possible. He should make frequent examination of his birth- lists, and deal, as soon as practicable, with every default as it arises ; and he should be prompt and diligent in his inquiries respecting the other children to whom his duties extend under section 1 2 of his " instructions," as issued by the Local Government Board. ill. Special Arrangements for Public Vaccination. 1. In towns which have regular weekly attendances for the per- formance of public vaccination, the only modification usually requi- site will consist in the vaccinator.s giving special daily attendances at the stilt ion at a fixed hour for the vaccination of cases of emer- gency. [\Vln-iv the town-district is of particularly large population (so that the ordinary average weekly number of primary vaccinations performed at the stations exceeds twenty), it may be convenient that during tin- stress of the epidemic the station should be open for the general performance of vaccination on two days (instead of one day) in each week.] It must, however, be distinctly under.-tood that the daily att-nl- - given as above are only for cases of emergency; and that which are not of emergency must be left to the times of general vaccination. It is on the regular weekly attendance.- that tin- vaccinator has to depend not only to maintain the. u.-ual performance <>f primary vaccination from arm to arm, hut also to furnish lymph f'r C8 re-vaccination and !'<] use in his special attendances ; -md the expe- rience of every recent epidemic of .smallpox ha- shown that to attempt at such times an indiscriminate dailv performance of vac- '1 II 466 APPENDIX. cination and re-vaccination leads only to difficulties and disadvan- tages. There are two reasons, indeed, for which at such times an adherence to systematic arrangements (with exception only for special cases) is of more than ordinary consequence ; first, because it is then peculiarly important that each primary vaccination should be done under conditions which scarcely admit of failure ; and secondly, because without system it is quite impossible pro- perly to meet the large demands for re-vaccination which at such times are sure to arise. Re-vaccinations, unless of persons residing in houses in which there is smallpox, or under other exceptional circumstances, should always be reserved for the regular vaccination 2. In districts (whether of town or country) which ordinarily have their public vaccinations performed at quarterly or half-yearly or other intervals, should smallpox break out at a time of year when vaccination is not going on, it will be necessary that the station for the district, or part of district, in which the disease is prevailing should at once be open, and that a weekly attendance should be given thereat for a limited period ; during which period the vaccina- tion officer should take steps as above directed for making the vaccination of the district, or part of district, as complete as possible. In districts of the kind now under consideration it will probably be more convenient that cases of emergency should be vaccinated at their own homes under the exceptional provisions of Regulation 1, Article 1, of the Order of Feb. 18, 1868 (above referred to) than that daily attendances should be given at the station. 3. Any exceptional vaccination arrangements made as above by the guardians with reference to epidemics of smallpox should be for some fixed period, not exceeding six weeks ; at the end of which period they can, in case of need, be renewed by a further order of the guardians ; but every such making or renewal of the exceptional arrangements should be reported without delay to the Local Government Board. N.B. The isolation of the sick, the disinfection of infected houses, and the disinfection or destruction of infected things, are very important means of checking the spread of smallpox ; and in order that such measures may be enforced, the Public Health Act, 1875, besides imposing penalties 011 the exposure of infected persons, the letting of infected houses, the sale of infected things, and other acts similarly dangerous to the public health, gives very important powers to sanitary authorities. These are stated in the official " Memorandum on the duties of sanitary authorities in reference to epidemics of smallpox." It is also to be observed that, so far as the destitute classes are visited by smallpox, boards of guardians, APPENDIX. 467 as poor law authorities, have opportunities, which it is desirable they should fully use, for securing disinfection and the isolation of the sick. VI. MEMORANDUM for the Assistance of GUARDIANS and others in framing and carrying out Arrangements for the Performance of PUBLIC VACCINATION. PUBLIC VACCINATION. Vaccination Acts, 1867 and 1871. Regulations of 1st December 1859, and Regulations of 1 8th February 1868. 1. In order to secure the best sort of vaccination, the operation should, as far as practicable, be performed with fresh lymph direct from arm to arm. The lymph should be carefully selected from the best-formed vesicles upon the healthiest children at the right period of the course of the vesicles. And the arrangements for public vaccination under the vaccination contracts ought to be framed so as to secure, as far as possible, these objects. 2. As, in ordinary circumstances, it is at the end of the week from vaccination that the arm of a child is in the state best fitted for yielding lymph, the attendances for the performance of public vaccination must be given at weekly intervals. 3. As, for keeping up vaccination in perfection, it is essential that a public vaccinator should have on each vaccinating occasion a large choice of children and of vesicles, it is obvious that the cases for vaccination must not be divided between too many stations, or distributed over too many vaccinating days. 4. It is only in very populous districts that weekly vaccination can be maintained efficiently throughout the year. If an attempt were made to keep up vaccination throughout the year at a vac- cination station to which (say) 100 cases are brought annually, it would be found that as the births are not equally spread over the whole year, and as accidental circumstances must often interfere with the bringing of children in particular weeks, there would not unfrequently be no cases at all at the station to supply lymph, and in the majority of weeks not a sufficient number of children to en- able the vaccinator to make a proper selection. 5. Hence, in districts which are not very populous, it is necessary that public vaccination should be performed at certain periods of the year, as at quarterly or half-yearly periods, weekly 468 APPENDIX. attendances being then given for two, three, four, or more successive weeks, according to the population for the accommodation of which the particular station is designed. 6. Without attempting to lay down a precise rule 011 a question which must largely be decided according to the circumstances of each locality, it may be said, generally, that any station at which there are less than 80 vaccinations annually should not be attended more frequently than at half-yearly periods. 7. Provision is made by the 12th section of the Vaccination Act, 1867, by which, in districts in which public vaccination is performed at intervals exceeding three months, parents of children attaining the age of three months do not become liable to penalty for the non-vaccination of their children until after the next public vaccination held in the district subsequently to their having at- tained that age. 8. Children living within two miles of a vaccination station cannot (unless under special circumstances) legally be vaccinated by the public vaccinator except at the station and at the time specified in the contract. If, however, some special reason require this rule to be departed from in any particular case, an entry stating the "special reason" must, in accordance with the Regulations of 18th February 1868, be made in the vaccinator's register. 9. Having regard to weather and to other considerations, the months of April and October will generally be found most suitable for half-yearly vaccination. 10. In framing periodical arrangements for districts in which there are two or more stations, the attendances should not commence in the same week at all the stations, but a week or two should be given for establishing at the most frequented station a supply of lymph with which to start vaccination at the others. 11. It is convenient that, as far as practicable, the stations of a district should be attended on the same week day, in order that, when necessary, lymph may be taken fresh from station to station. 12. In districts in which public vaccination is fixed to take place periodically, the public vaccinator should, on the day week preceding the first day of the periodical attendances appointed under Schedule A to the contract, vaccinate with lymph stored by himself or obtained from the National Vaccine Establishment, or some other trustworthy source, two or three selected children. Arrangements should be made for bringing these children to the station on the day appointed for beginning the periodical vaccination of the dis- trict, and the lymph from their arms will afford means of starting such vaccination satisfactorily. The public vaccinator in registering these vaccinations should, in accordance with Regulation 1 of 18th APPENDIX. 469 February 1868, state in his register the special reason for their not having been vaccinated at the station. 13. By section 7 of the Vaccination Act, 1867, it is provided that all vaccination stations (except at the residence or surgery of the public vaccinator) shall be provided by the guardians. 1 4. Vaccination stations must be within the district for which they are to serve, and must not be fixed at union workhouses, as the independent poor are unwilling to resort for vaccination to an insti- tution connected with pauper relief. The same objection applies, though perhaps in a minor degree, to the appointment of pauper pay stations as vaccination stations. The Board further consider it undesirable that public-houses should be selected for the purpose. Whatever room or place be selected as a vaccination station, it is essential that the public vaccinator should have the exclusive use of it during the time of vaccination. 1 5. In large towns the vaccination station should, if possible, be at some public building, e.g. town hall, meeting hall, or school, or at rooms specially hired for the purpose. Various objections exist to the use of the surgeries of public vaccinators in such towns, especially that they rarely afford the accommodation necessary for the number of children likely to be brought, and that they do not possess the distinctive public character which is desirable. 16. In rural districts schoolrooms are frequently found con- venient for the purpose. It is of course necessary that the assent of the managers of the school should be obtained ; that the vaccina- tion should be fixed at such an hour as not to interfere with school arrangements ; and particularly that the public vaccinator should have at the time fixed for vaccination the exclusive use of the schoolroom or class-room appointed for the purpose. 17. In order to secure at vaccination stations the punctual 1 Tinging together of children (from some of whom lymph has to be taken for the vaccination of others), it is desirable that the time of attendance notified to parents should be that at which vaccina- tion is intended to begin, as "at 10 A.M.," not "from 10 to 11 A.M. 18. The hour of public vaccination should never be fixed so late in the day as to make it impracticable to complete the business of the station by daylight. 19. Enough time (which should rarely be less than one hour) should be allowed between the times of attendance at different stations to enable the public vaccinator, after performing vaccina- tion and making the necessary entries in the register at one station, to arrive punctually at the next. 20. The payments to be made for vaccinations performed at 470 APPENDIX. other places than stations should not in any case exceed the sum that would have been paid had the operation been performed at the station nearest to the residence of the person vaccinated. 21. Every vaccination contract must contain a stipulation or condition in accordance with section 7 of the Vaccination Act, 1867. The form in general use is as follows : And it is hereby mutually agreed by and between the parties hereto, that no money shall be paid to the said in respect of any person vaccinated by him until he shall have transmitted to the vaccination officer a certificate of the suc- cessful vaccination of such person, and otherwise fulfilled on his part the requirements of the Vaccination Acts, 1867 and 1871, and the regulations made thereunder. 22. The course to be taken if smallpox break out in a district where ordinarily the public vaccination is carried on periodically, is explained in the Office Memorandum on the steps to be taken by guardians in places in which smallpox is epidemic. 23. If an infectious disease, such as scarlatina, measles, or diphtheria, prevail to such an extent in a district that the public vaccinator considers that the bringing of children together for vac- cination would be likely to spread the disease, he should represent the facts to the guardians for communication with the Board, who will, on sufficient cause shown, be ready to authorise the postpone- ment of the attendances prescribed by the contract. 24. A contractor for public vaccination must be a registered medical practitioner qualified in medicine and surgery, and (if admitted to practice since 1st January 1860) possessing a special certificate of proficiency in vaccination from one of the Examiners authorised to grant such certificates for the purposes of the order of 1st December 1859. 25. The duties of a public vaccinator must be habitually dis- charged by the contractor himself, and the employment of a deputy must be limited to those occasions when unavoidable circumstances prevent the contractor's personal attendance. 26. In order to provide for occasions when the public vaccinator is unavoidably absent, it is proper that a deputy (who must possess the same qualifications as a contractor) should be appointed under the Regulations of 1st December 1859, and that the appointment, after being submitted by the guardians for the approval of ^the Local Government Board, should be endorsed upon the contract. It must be understood, however, that the approval of such appoint- APPENDIX. 471 ment is not to be taken as authorising any habitual omission on the part of the public vaccinator to perform in person the duties for which he is responsible. 27. Public vaccination cannot, under any circumstances, be legally performed by an unqualified person, and the guardians can- not legally pay for any vaccination so performed. VII. RE- VACCINATION. By vaccination in infancy, if thoroughly well performed and successful, most people are completely insured for their whole life- time against an attack of smallpox ; and in the proportionately few cases where the protection is less complete, smallpox, if it be caught, will, in consequence of the vaccination, generally be so mild a disease as not to threaten death or disfigurement. If, however, the vaccination in early life have been but imperfectly performed, or have from any other cause been but imperfectly successful, the protection against smallpox is much less satisfactory ; neither last- ing so long, nor, while it lasts, being nearly so complete as the protection which first-rate vaccination gives. In consequence of the large amount of imperfect vaccination which has till very recent years existed, the population contains very many persons who, though nominally vaccinated, and believing themselves to be pro- tected against smallpox, are really liable to infection, and may, in some cases, contract as severe forms of smallpox as if they had never been vaccinated. Partly because of the existence of this large number of imperfectly vaccinated persons, and partly because also even the best infantine vaccination sometimes in process of time loses more or less of its effect, it is advisable that all persons who have been vaccinated in infancy should) as they approach adult life, undergo RE-VACCINATION. Generally speaking, the best time of life for re-vaccination is about the time when growth is completing itself, say from 15 to 18 years of age ; and persons in that period of life ought not to delay their re-vaccination till times when there shall be special alarm of smallpox : first, because they can never tell how soon, or by what chance, they may (even at times when there is little prevalence of that disease) be exposed to its infection ; and secondly, because of the much more advantageous conditions under which the re-vaccination can be performed when it can be done leisurely, than when it has to be done under the pressure caused by a panic. When, however, smallpox becomes epidemic, not only should all persons above 15 years of age who had hitherto neglected to have themselves re -vaccinated be very careful to 472 APPENDIX. neglect it no longer, but in proportion as there is prevalence of smallpox in any neighbourhood, or as individuals are from per- sonal circumstances likely to meet chances of infection, even the age of 1 5 should not be waited for, especially not by young persons whose marks of previous vaccination are unsatisfactory. The rule applicable to circumstances of special danger is this : that every one past childhood on whom re-vaccination has not before been successfully performed, should without delay be re-vaccinated. Ke-vaccination, once properly and successfully performed, does not appear ever to require repetition. The nurses and other servants of the London Smallpox Hospital, when they enter the service (unless it be certain that they have already had smallpox), are invariably submitted to vaccination, which in their case generally is re-vaccination, and is never afterwards repeated ; and so perfect is the protection that, though the nurses live in the closest and most constant attendance on smallpox patients, and though also the other servants are in various ways exposed to special chances of in- fection, the resident surgeon of the hospital, during his forty-one years of office there, has never known smallpox affect any one of these nurses or servants. Legal provisions for re-vaccination are made in the 8th Section of the Vaccination Act, 1867, in Section IV. of the Regulations which the Lords of the Council, under authority of that Act, issued in their order of February 18, 1868, and in the 9th Section of the Vaccination Act, 1871. Under these provisions, Re-vaccination is now performed by all public vaccinators at their respective vaccinat- ing stations ; and, so far as is not inconsistent with the more im- perative claims for primary vaccination, any person coming within the terms of these provisions may, on applying to the public station of the district in which he resides, obtain re-vaccination free of personal cost. EDWARD C. SEATON, M.D. Medical Officer. Local Government Board, October 17, 1876. VIII. MEMORANDUM issued by the NATIONAL VACCINE ESTABLISHMENT with SUPPLIES of CALF-LYMPH. CALF-LYMPH VACCINATION. The present lymph is sent for the commencement of a local APPENDIX. 473 series of ami-to-arm vaccinations. In using it for this purpose, it is to be remembered (1.) That, as compared with humanised lymph, calf-lymph is much less easy of removal from the "points;" (2.) That such lymph does not "take" with the same degree of certainty as humanised lymph ; (3.) That the course of the early vaccinations of a series is not so regular as with humanised lymph. Any child chosen for vaccination with the lymph now sent should be between three and five months old, and should be selected for its own good health and for the known good health of its parents. Two large points are needed for the vaccination of a single child. The lymph on them should be moistened for a minute with water, and should then be thoroughly rubbed into each of four or five places prepared on the child's arm or arms. Each of these places should be made by abrasion with a blunt lancet over an area of an eighth of an inch square. In vaccinating subsequent children, lymph should be taken from fully -developed vesicles before the formation of an areola round them. The vaccination of the first child is liable to be retarded, and that of the next few children is frequently acceler- ated ; so that it is desirable to inspect the several vaccinifers on other days beside the day-week, in order that the best time for taking lymph may be assured. Calf-lymph for the vaccination of children is best preserved on points ; but if it is desired to establish local series of calf-to-calf vaccinations, lymph in tubes or between glasses is to be preferred. Special application to the National Vaccine Establishment should be made if lymph stored in either of the latter ways is desired. One or more perfectly healthy calves of four to five months old should be in readiness at the time of making the application. August 1881. IX. GENERAL MEMORANDUM on the PROCEEDINGS which are advisable in PLACES attacked or threatened by EPIDEMIC DISEASE. 1 . Wherever there is prevalence or threatening of cholera, diph- tlit-i'ia, I't-vrr, or any other epidemic disease, it is of more than 474 APPENDIX. common importance that the statutory powers conferred upon sani- tary authorities for the protection of the public health should be well exercised by those authorities, acting with the advice of their medical officers of health. 2. Proper precautions are equally requisite for all classes of society. But it is chiefly with regard to the poorer population, therefore chiefly in the courts and alleys of towns, and at the labourers' cottages of country districts, that local authorities are called upon to exercise vigilance, and to proffer information and advice. Common lodging-houses, and houses which are sub-let in several small holdings, always require particular attention. 3. Wherever there is accumulation, stink, or soakage of house refuse, or of other decaying animal or vegetable matter, the nuisance should as promptly as possible be abated, and precaution should be taken not to let it recur. Especially examination should be made / as to the efficient working of sewers and drains, and any nuisance therefrom, or from any foul ditches or ponds, should be got rid of * *(_^ without delay. The ventilation of sewers, the ventilation and trap- ping of house drains, and the disconnection of cistern overflows and sink pipes from drains, should be carefully seen to. The scavenging of the district, the state of receptacles for excrement, and of dust- bins, will require particular and sustained attention. In slaughter- houses, and wherever animals are kept, strict cleanliness should be enforced. 4. In order to guard against the harm which sometimes arises from disturbing heaps of offensive matter, it is often necessary to combine the use of chemical disinfectants (see 1 7) with such means as are taken for the removal of filth ; and in cases where removal is for the time impossible or inexpedient, the filth should always be disinfected. Disinfection is likewise desirable for unpaved earth close to dwellings, if it be sodden with slops and filth. Generally, where cholera or enteric (typhoid) fever is in a house, the privy requires to be disinfected. 5. Sources of water-supply should be well examined. Those ^ /4 which are in any way tainted by animal or vegetable refuse, above all, those into which there is any leakage or filtration from sewers, -' drains, cesspools, or foul ditches, ought no longer to be drunk from. "344 JC/~ Especially where the disease is cholera, diarrhosa, or enteric fever, ffa it is essential that no foul water be drunk. If unfortunately the only water which for a time can be got '/'fcju should be open to suspicion of dangerous organic impurity, it ought at least to be boilecl before it is used for drinking, but then not to be drunk later than twenty-four hours after it has been boiled. Or unc i er medical or other skilled direction, water, in quantities suffi- APPENDIX. 475 cient for one day's drinking in the house, may be disinfected by a very careful use of Cond/s red disinfectant fluid ; which should be added to the water (with stirring or shaking) in such number of drops that the water, an hour afterwards, shall have the faintest pink colour which the eye can distinctly perceive. Filtering of the ordinary kind cannot by itself be trusted to purify water, but is a good addition to either of the above processes. It cannot be too distinctly understood that dangerous qualities of water are not ob- viated by the addition of wine or spirits. When there appears any probable relation between the distribu- tion of disease and of milk supplies, the cleanliness of dairies, and the purity of the water used in them, should be carefully investi- gated. 6. The washing and lime-whiting of uncleanly premises, especi- ally of such as are densely occupied, should be pressed with all practicable despatch. 7. Overcrowding should be prevented. Especially where disease j has begun, the sick-room should, as far as possible, be free from( persons who are not of use or comfort to the patient. J 8. Ample ventilation should be enforced. It should be seen that window -frames are made to open, and that windows are suffi- ciently opened. Especially where any kind of infective fever has begun, it is essential, both for patients and for persons who are about them, that the sick-room and the sick -house be constantly well traversed by streams of fresh air. 9. The cleanliest domestic habits should be enjoined. Refuse matters which have to be cast away should never be allowed to remain within doors ; and things which have to be disinfected or cleansed should always be disinfected or cleansed without delay. 10. Special precautions of cleanliness and disinfection are neces- sary with regard to infective matters discharged from the bodies of the sick. Among discharges which it is proper to treat as infective, are those which come, in cases of smallpox, from the affected skin ; in cases of cholera and enteric fever, from the intestinal canal ; in cases of diphtheria, from the nose and throat ; likewise, in cases of any eruptive or other epidemic fever, the general exhalations of the sick. The caution which is necessary with regard to such matters must, of course, extend to whatever is imbued with them ; so that bedding, clothing, towels, and other articles, which have been in use by the sick, may not become sources of mischief, either in the house to which they belong or in houses to which they are conveyed. Moreover, in enteric fever and cholera, the evacuations should be regarded as capable of communicating an infectious quality to any night-soil with which they are mingled in privies, drains, or cess- 4*76 APPENDIX. pools ; .and this danger is best guarded against by thoroughly dis- infecting them before they are thrown away (see 17) ; above all, they must never be cast where they can run or soak into sources of drinking water. 11. All reasonable care should be taken not to allow infective disease to spread by the unnecessary association of sick with healthy persons. This care is requisite, not only with regard to the sick- house, but likewise with regard to day schools and other establish- ments wherein members of many different households are accustomed to meet. 12. "Where dangerous conditions of residence cannot be promptly remedied, it will be best that the inmates, while unattacked by dis- ease, remove to some safer lodging. If disease begins in houses where the sick person cannot be rightly circumstanced and tended, medical advice should be taken as to the propriety of removing him to an infirmary or hospital. Every sanitary authority should have in readiness a hospital for the reception of such cases. 13. Privation, as predisposing to disease, may require special measures of relief. 14. In certain cases special medical arrangements are necessary. For instance, as cholera in this country almost always begins some- what gradually in the comparatively tractable form of what is called " premonitory diarrhoea," it is essential that, where cholera is epi- demic, arrangements should be made for affording medical relief without delay to persons attacked, even slightly, with looseness of bowels. So again, where smallpox is the prevailing disease, it is essential that all unvaccinated persons (unless they previously have had smallpox) should very promptly be vaccinated ; and that re- vaccination should be performed in cases properly requiring it. 15. It is always to be desired that the people should, as far as possible, know what real precautions they can take against the dis- ease which threatens them, what vigilance is needful with regard to its early symptoms, and what (if any) special arrangements have been made for giving medical assistance within the district. For the purpose of such information printed hand-bills or placards may usefully be employed, and in cases where danger is great, house-to- house visitation by discreet and competent persons may be of the utmost service, both in quieting unreasonable alarm, and in leading or assisting the less educated and the destitute parts of the popula- tion to do what is needful for safety. 16. The present memorandum relates to cases of emergency. Therefore the measures suggested in it are all of an extemporaneous kind ; and permanent provisions for securing the public health have not been in express terms insisted on. It is to be remembered, APPENDIX. 477 however, that in proportion as a district is habitually well cared for by its sanitary authorities, the more formidable emergencies of epidemic disease are not likely to arise in it. 1 7. Chemical disinfectants are of two great classes, and hitherto it is not certain which of the ^wo classes acts best. The one class is well represented by chlorine and certain of its compounds ; the other is well represented by carbolic acid. Under the former system, the solution of chloride of lime may be used for minor domestic purposes, chloride of lime itself to any masses of filth, and chlorine gas for disinfection of rooms. Under the latter system carbolic acid may be used for minor domestic purposes, sulphate or perrhloride of iron to any masses of filth, and sulphurous acid gas for disinfection of rooms. These systems do not combine well with one another, and in the choice which has to be made between them, it will be convenient that the sanitary authority of each district should declare which of the two systems it adopts, and that all private disinfection in the district should follow such lead of the authority. The detail in each case should be carried out under medical advice. In public disinfection establishments for the dis- infection of wearing apparel, bedding, curtains, and other large household articles, the most convenient process consists in employ- ment of high degrees of heat. X. SUGGESTIONS by the SOCIETY of MEDICAL OFFICERS of HEALTH, for Preventing the Spread of Infectious or Contagious Diseases, such as SCARLET FEVER, SMALL- POX, FEVER, etc. 1. Separate the sick person from the rest of the family directly illnes.- appears, placing him, if possible, in a room at the top of the house, and taking cart- in remove carpets, curtains, and all unneces- sary articles of furniture and clothing therefrom. 2. Admit fresh air l>y opening the upper sash of the window. The fireplace should be kept open, and a fire lighted if the weather permits. Fresh air should be freely admitted through the whole h<>use by means of open windows and doors. The more air that passes through the house, the less likely is the disease to spread. 3. Hang up a sheet outside the door of the sick-room, and keep it w-t with a mixture made either witli a quarter of a pint of car- bolic acid (No. 4), or a pound of chloride of lime and a gallon of water. 4. Everything that passes from the sick person should be received i( 478 APPENDIX. into vessels containing half a pint of a solution of green copperas, made by dissolving one pound of the copperas in a gallon of water. A like quantity of the solution of copperas should be added to the dis- charges before emptying them into the closet. 5. Every sink, closet; or privy should have a quantity of one of the above-named disinfectants poured into it daily, and the greatest care should be taken to prevent the contamination of well or drinking water by any discharges from the sick person. 6. All cups, glasses, spoons, etc., used by the sick person should be first washed in the above-named solution of carbolic acid, and afterwards in hot water, before being used by any other person. 7. No article of food should be allowed to remain in the sick- room. No food or drink that the sick person has tasted, or that has been in the sick-room, should be given to any one else. 8. All bed and body linen, as soon as removed from the sick person, and before being taken from the room, should be first put into a solution of carbolic acid of the above-mentioned strength, remaining therein for at least an hour and afterwards boiled in water. 9. Instead of handkerchiefs, small pieces of rag should be used, and these, when soiled, should be immediately burnt. 10. Persons attending on the sick should not wear woollen garments, as they are likely to retain infectious poison ; dresses of cotton, or of some washable material, should be worn. Nurses should always wash their hands immediately after attending to the sick person, using carbolic acid soap instead of ordinary soap. 11. It is of the utmost importance that the sick-room be not frequented by others than those in immediate attendance on the sick, as the clothing of visitors is very liable to carry away infection. 12. The scales and dusty powder which peel from the skin in scarlet fever, and the crusts in smallpox, being highly infectious, their escape may be prevented by smearing the body of the sick person all over every day with camphorated oil. This, and the after use of warm baths and carbolic acid soap, are most essential. The sick person must not be allowed to mix with the rest of the family until the peeling has entirely ceased, and the skin is perfectly smooth ; clothes used during the time of illness, or in any way exposed to infection, must not be worn again until they have been properly 13. When the sickness has terminated, the sick-room and its contents should be disinfected and cleansed. This should be done in the following manner : Spread out and hang upon lines all articles of clothing and .bedding ; well close the fireplace, windows, and all openings ; then take a quarter to half a pound of brimstone, APPENDIX. 4*79 broken into small pieces ; put them into an iron dish, supported over a pail of water, and set fire to the brimstone, by putting some live coals upon it. Close the door, and stop all crevices, and allow the room to remain shut up for twenty-four hours. The rooms should then be freely ventilated, by opening the door and windows, the ceiling should^ be whitewashed, the paper stripped from the walls and burnt, and the furniture, and all wool and painted work be well washed with soap and water containing a little chloride of lime. Beds, mattresses, and articles which cannot well be washed, should, if possible, be submitted to the action of heat in a disinfect- ing chamber, usually provided by the local authorities. Until this process of disinfection is effectually carried out, the room cannot be safely occupied. 14. Children should not be allowed to attend school from a house in which there is infectious disease, as, although not ill them- selves, they are very likely to carry the infection, and so spread the disease. No child should be allowed to re-enter a school without a certificate from the medical attendant, stating that he can do so without any danger of infecting other children. 15. In case of death, the body should not be removed from the room, except for burial, unless taken to a mortuary, nor should any article be taken from it until disinfected as before directed in Kule No. 1 3. The body should be put into a coffin as soon as possible, with a pound or two of carbolic powder. The coffin should be fastened down, and the body buried without any delay. Attention is particularly directed to the following provisions of the Sanitary Laws, in reference to " Infectious Dis- orders " : 1. The owner or occupier may be required to cleanse and disin- iVi-t ;my house or room, or the cabin or berth of any ship or vessel, and the articles contained in it likely to retain infection where infectious disease has existed under a penalty not exceeding 10s. a day for neglect. 2. If any person, suffering from any dangerous infectious dis- order, shall enter a cab or other public conveyance, without inform- ing the driver thereof that he is so suffering, he shall be liable to a penalty not exceeding 5. 3. Any person suffering from any dangerous infectious disorder such as fever, scarlet fever, smallpox, etc. who exposes himself in any street, school, church, chapel, theatre, or other public place ; or in any omnibus or other public conveyance, and any person in 480 APPENDIX. charge of one so suffering, who so exposes the sufferer, shall be liable to a penalty not exceeding .5. 4. Any person who, without previous disinfection, gives, lends, sells, or moves to another place, or exposes any bedding, clothing, rags, or other things which have been exposed to infection, becomes liable to a penalty not exceeding 5. 5. Any person who lets a house, room, or part of a house, in which there has been infectious disease, without having such house or room, and all articles therein liable to infection, disinfected to the satisfaction of a qualified medical practitioner, is liable to a penalty not exceeding 20. This applies to public -houses, hotels, and lodging-houses. 6. If any person who lets, or shows for hire, any house or part of a house, makes any false statement as to the fact of there being then in such house, or having within six weeks previously been therein, any person suffering from an infectious disease, such person answering falsely shall be liable to imprisonment, with or without hard labour, or to a penalty not exceeding 20. J. NORTHCOTE VlNEN, M.D. J St. John's, Southward, ( . , y W. H. CORFIELD, M.D. (Oxon.) C* 10 Bolton Row, Mayfair. ) March 1875. XL MEMORANDUM with respect to KETURNS of DEATHS from Registrars and RETURNS of PAUPER SICKNESS from District Medical Officers. Under Articles 14 and 15 of Section IV. of the General Order of the llth November 1872, every medical officer of health whose appointment has been approved by the Board is required to prepare an annual report, comprising, amongst other things, tabular state- ments of the mortality and of the pauper sickness in his district. Information as to mortality and sickness is required by the medical officer of health not only in preparing these statements, but also in discharging the duties of his office, and this Memorandum is intended to indicate the arrangements which should be made for furnishing him with such information. 1. The sanitary authority should, under section 28 of the Births and Deaths Registration Act, 1874, require the Registrars of Births and Deaths to supply returns of the deaths registered within their respective districts. These returns should be made weekly as regards all deaths registered as having occurred within the Registrar's APPENDIX. 481 district during the preceding week ; but an immediate notice should be given of all deaths from infectious disease in fresh localities, and of all groups of deaths from such disease, or from diarrhrea, in any localities. The Eegistrar-General has prepared for the use of Registrars a form in which the weekly returns may be conveniently made. A fee of twopence for each entry is payable by the sanitary authority. 2. The medical officer of health should be regularly supplied with information of the new cases of pauper sickness in his district. This information is valuable to him, not only as an index to the prevalence of non-fatal disease among all classes in the sanitary dis- trict, but as giving him occasion to exercise useful and immediate sanitary supervision over localities which are most apt to require such supervision. It is requisite for this object, as well as to enable him to complete the annual returns, that (except where the medical officer of health is himself the Poor -Law medical officer for the whole sanitary area under his superintendence, in which case he will of course possess this information) the guardians should instruct their clerk to copy from the district medical officer's relief lists the new cases whicli are reported at each meeting of the guardians, and to forward the same promptly and regularly to the medical officer or officers of health within the union. Arrangements should be made for the regular transmission of the copies referred to as early as practicable after each meeting. It is competent to the sani- tary authority, whether rural or urban, to pay a reasonable sum to the clerk to the guardians for the supply of this information. 3. The guardians should request the Poor-Law medical officers to give to the medical officer of health (or to the inspector of nuisances, for the information of the medical officer of health) acting within their respective districts, the earliest possible information of cases of dangerous infectious disease under their charge ; as it is evident that unless such information is given as soon as the cases occur, the action of the sanitary authority in regard to the preven- tion of infection may often fail in its effect. 4. Under the Board's General Order of the 12th February 1879, it is incumbent upon all district and workhouse medical officers appointed since the 28th February 1879, to furnish the iiu-dical officer of health with returns of pauper sickness and deaths, as well as to notify the outbreak of dangerous infectious disease. A similar obligation lias been imposed by the Board's Order of the 14th June 1879 upon medical officers of district schools appointed after the 25th June 1879. JOHN LAMBERT, Secretary. Local Government Board, 20th July 1879. 2 I 482 APPENDIX. XII. ANNUAL KEPORTS of MEDICAL OFFICERS of HEALTH. Instructions. Every medical officer of health, appointed under the order of the Local Government Board dated the llth November 1872, is required to make an annual report With regard to each sanitary district, or division of a district, which is under his super- intendence. This report is to be for the year ending the 31st of December, or, if the officer at that date has not been in office for a whole year, then for so much of the year as has elapsed since .Ms appointment. The report is to be made to the sanitary authority, and a copy of it is to be sent by the medical officer of health to the Local Government Board. It should be made as soon as practicable after the expiration of the year to which it relates. The medical officer of health ought not, in general, to have any difficulty in doing this within a month or six weeks ; but if from any special circum- stances the report cannot be completed within six weeks, it should be understood that the delay must not be indefinite, and that the report, complete or incomplete, should be in the hands of the sani- tary authority within, at most, three months from the end of the year. The Board's copy of the report should be forwarded to them when the original is sent to the sanitary authority, except where the report is likely to be printed by order of the authority. In such cases the Board 'need only be supplied with a printed copy. But in all cases in which the report cannot be sent to the Board within six weeks from the end of the year, they should be informed by the medical officer of health as to the reason for the delay. Article 14 of Section IV. of the Board's Order provides that the annual report is to contain information as to the sickness and deaths that have occurred during the year ; the measures taken in order to prevent the spread of disease ; and the proceedings of the medical officer of health. It would be well if the report, so far as it relates to the medical officer of health's proceedings, were, in the main, the same in arrangement as the articles which deal with these proceed- ings ; thus stating first what has been done under articles 1-3, which make it the duty of the medical officer of health to inform himself as to the sanitary state of the district, and to make the inquiries and inspections necessary for this purpose ; next, the advice which has been given to the sanitary authority under articles 4 and 5 ; and lastly, the action he has taken under articles 6-10 in the several matters therein referred to. As regards the duties imposed under these several articles, each of which will thus be reported on, special attention should be had to the provisions of article 3, which directs systematic inspections of APPENDIX. 483 t the district to be made by tlie medical officer of health, apart from the inquiries which under other articles of the Order he has to make into particular outbreaks of disease, or into unwholesome conditions to which his attention may have been specially called by complaints or otherwise. The object of these systematic inspections is that the medical officer of health may assure himself that he is well acquainted with all the discoverable circumstances which are likely to affect the public health in his district. How often these inspections re- quire to be made, and how detailed the inquiries should be, must be determined by the particular circumstances of the locality. In some neighbourhoods a house-to-house inspection should as far as practicable be made ; in others this may not be needful ; but every medical officer of health should at certain times set himself to examine into the state of his district, devoting some time to each portion of it, so as to be sure that no part escapes his notice. In making such an inspection the medical officer of health will usually require the assistance of the inspector of nuisances. Of these inspections, of the judgment he has formed thereon as to the sani- tary state of the district, and of the advice he has in consequence given to the sanitary authority, and the action taken by the autho- rity thereon, the annual report should contain a full account. As regards the tabular statements of sickness and mortality (forms for which statements are now issued by the Board) only one observation appears to be needful. The district under the super- intendence of a medical officer of health will often contain several parts evidently differing in their circumstances, or having very differ- ent death-rates, either of all registered deaths, or of those from some particular disease or class of diseases. T,he observation of these differ- ences can scarcely fail to lead to valuable information, and it is in view of those differences that in article 14 the tabular statements are required to be classified according to localities, and that provision for such a classification is made in the enclosed forms for returns of deaths. In the absence of any ascertained differences of the above sort, it will still be desirable to classify the deaths of the district according to the part of the district in which they occur ; and for this purpose any areas of known population (such as parishes, groups of parishes, townships, or wards) may be taken as representing "localities" for the purposes of the Order. Classification on this basis will be likely to lead to the discovery of real differences when tin- returns for several years can be compared together. Having regard to the imperfect character of the information which is obtainable as to non-fatal sickness, such a classification cannot, it seems, be generally attempted in the sickness returns ; but in particular cases medical officers of health may be able, and 484 APPENDIX. may find it useful, so to classify the pauper sickness of which they receive information. What has been said above with regard to the information which an annual report should contain must be understood, not as suggest- ing that the report should be limited to these subjects, or that more detailed or differently arranged tabular statements may not be added, but as indicating the minimum of information which will satisfy the requirements of the Board's Order. Many medical officers of health will doubtless, and with great advantage to the administration of their district, give much more detailed informa- tion than they are actually required to furnish, ancj. will give espe- cial prominence to the questions to which they have been led by the circumstances of the past year to devote particular attention, or in the investigation of which they may have arrived at valuable con- clusions. Any information of this kind will be gladly received by the Local Government Board. EDWARD 0. SEATON, M.D., Medical Officer. Local Government Board, December 1877. APPENDIX. 485 II 1 | 1^ i I 4S i it Q o O S S I |i c 'C -M" r- QJ ^ - o T a i i s S CO * 1 1 k "orms for the birth. Tom Messrs. Knig erthyr-Tydlil. 1 | 1 ill ,_, J 486 APPENDIX. XIV. NOTICE of INFECTIOUS DISEASES occurring amongst PAUPERS. (Author's Form.) SANITARY AUTHORITY. Return of District Medical Officer. Name. Age. Residence. Disease. Probable Cause. Steps recommended. To be folded and forwarded, unsealed, to Sanitary Inspector. Signed, Date, District Medical Officer. Return of Sanitary Inspector. Sanitary Condition of Premises. Action taken. To be folded and forwarded, unsealed, to Medical Officer of Health. Signed, Date, Sanitary Inspector. Explanatory Note. The above form should be printed on paper foolscap size, with the Returns of the District Medical Officer and Sanitary In- spector on one side, and the addresses of the Medical Officer of Health and Sanitary Inspector on the other. APPENDIX. 487 XV. FORMS of TABLES of MORTALITY issued by the SOCIETY of MEDICAL OFFICERS of HEALTH. The accompanying forms of Tables of Mortality have been drawn up by the Society of Medical Officers of Health to take the place of those issued in 1874 ; the Society being of opinion that certain changes are necessary, as the result of a new nomenclature of diseases prepared by the Royal College of Physicians, and a new method of classification adopted by the Registrar-General of England and Wales. In issuing these forms the Society wish again to express their opinion that it is desirable that the returns of all medical officers of health, in England and Wales, should be based on a uniform system, and they have, therefore, so arranged these forms that they can be conveniently used by those medical officers of health who report to the Local Government Board, as well as by all others. The Society also again recommend that 1. All statistical returns be made out to the end of the registration year, as defined in the reports of the Registrar-General, viz. up to December 31 or thereabouts. 2. That the numbers of the tables adopted by the Society be in all cases appended to these tables when used ; and that, to avoid confusion, different numbers be assigned to any other tables which it may be thought fit to insert in an Annual Report. The purport of each table is fully explained, the rates of mortality should in each table be calculated on the corrected number of deaths given in Table III., and it is thought that the information contained in the table headed "Summary of Table III." might, with advantage, be given in the body of the Report. J. NORTHCOTE VlNEX, M.D., \ St. John's South wark, S.E. ( Hon. Sees. 158 Camden Road, N.W. London, 1883. SHIRLEY F. MURPHY, ( rj 488 APPENDIX. TABLJE I. Showing the Population, Inhabited Houses, Marriages, Births, and Deaths, for the Year 18 and 10 years preceding. GROSS NUMBERS. The Year.i Estimated Population. No. of Inhabited Houses. f Registered Births. CORRECTED NUMBER OF DEATHS. Deaths in Public Institutions. Total all Ages. Under One Year. Under Five Years. 18 18 18 18 18 18 18 18 18 18 18 Average of) 10 Years, Vj 18 18 J NOTES. 1. Population at Census 18 2. Average Number of Persons in each house at Census 18 3. Area of District in acres. 1 For statistical purposes the Registrar-General estimates the population to the middle of the year on the basis of the rate, of increase ruling between the two preceding census periods. The estimate of population may be checked by the known number of inhabited houses, and by the average number of inmates per house, as ascertained at the preceding census. APPENDIX. 489 o S "S O ~ '- ~z S > i H hi ll'^I ||T| - ^|3 ^ = ""^ Q = i .. ^ !T t- S Pi i a Correct ].(! 1'i'l'Ulill i' 1 *-*-* 2 oo OOOOCOOOQOOOOOOOOOOO O^rn 490 APPENDIX. TABLE III. Showing Deaths registered from all Causes during the Year 18 NOTE. The Deaths of non-Residents occurring in Public Institutions situated in the District are excluded, and the Deaths of Residents occurring in Public Institutions situated beyond the limits of the District are included. J. Specific Febrile, or Zy- motic Diseases. II. Parasitic Diseases. III. Dietic Diseases. IV. Constitutional Diseases. V. Developmental Diseases. VI. Local Diseases. VII. Deaths from Violence. VIM. Deaths from Ill-defined and not Specified Causes, Totals . AGES. TOTALS. 55 to 60 i to 1 1 to 5 5 to 15 15 to 25 25 to 35 35 to 45 45 to 55 55 to 65 65 to 75 75 to 85 If 1. Specific Febrile or Zymotic Diseases. 1. Miasmatic Diseases. ( Vaccinated . Smallpox -j Unvaccinated I^No Statement Measles ...... Scarlet Fever . . Typhus Whooping- Cough .... Diphtheria ..... Simple Continued and Ill-defined Enteric or Typhoid Fever Other Miasmatic Diseases 2. Diarrhceal Diseases. Simple Cholera .... Diarrhoea, Dysentery 3. Malarial Diseases. Remittent Fever .... Ague 1 By filling in this column the Statistics of Table III. will be made comparable with those of the Weekly and Quarterly Returns of the Registrar-General, and also available for the Reports required by the Local Government Board. APPENDIX. 491 AG ES oa a o . >25 5 5 6 5 g"E 5 > (i (i > to ) 88 o 5 )35 > 5 5 5 5 g| H 4. Zoogenous Diseases. Cow-pox and effects of Vaccination . Other Diseases (e.g. Hydrophobia, Glanders, Splenic Fever) 5. Venereal Diseases. Syphilis Gonorrhoea, Stricture of Urethra 6. Septic Diseases. Erysipelas Pyaemia, Septicaemia Puerperal Fever .... II. Parasitic Diseases. Thrush, and other Vegetable Para- sitic Diseases .... Worms, Hydatids, and other Animal Parasitic Diseases III. Dietic Diseases. Want of Breast Milk, Starvation Chronic Alcoholism .... Delirium Tremens .... IV. Constitutional Diseases. Rheumatic Fever, Rheumatism of the Heart . . . . Rheumatism ..... Gout .'..... Rickets ...... Cancer, Malignant Disease Tabes Mesenterica .... Tubercular Meningitis, Hydrocephalu Phthisis Other forms of Tuberculosis, Scrofula 1'urpura. Ihi'iiiorrha^i'- 1 Matin-sis Ai i.i -miii, Chlorosis, Leucocythaemia . Glycosuria, Diabetes Mellitus . Other Constitutional Diseases . 492 APPENDIX. V. Developmental Diseases. Premature Birth Atelectasis .... Congenital Malformations Old Age ..... VI. Local Diseases. 1. Diseases of Nervous System. Inflammation of Brain or Membranes Apoplexy, Softening of Brain, Hemi- plegia, Brain Paralysis Insanity, General Paralysis of the Insane ..... Epilepsy ..... Convulsions . . Laryngismus Stridulus (Spasm of Glottis) . . . Disease of Spinal Cord, Paraplegia, Paralysis Agitans Other Diseases of Nervous System . 2. Diseases of Organs of Special Sense. .g. of Ear, Eye, Nose) . 3. Diseases of Circulatory System. Pericarditis . . . Acute Endocarditis . Valvular Diseases of Heart Other Diseases of Heart . Aneurism .... Embolism, Thrombosis . Other Diseases of Blood- Yessels 4. Diseases of Respiratory System. Laryngitis ~roup niphysema, Asthma Bronchitis 3 neumonia Pleurisy . Other Diseases of Respiratory System AGES. APPENDIX. 493 5. Diseases of Digestive System. AGES. 1 to 1 1 to 5 5 to 15 15 to L'5 2fi fa :;5 35 t< 45 45 '55 65 to to to 5565 75 75 t< Sf !| 55 to GO Dentition Sore Throat, Quinsy Diseases of Stomach .... Enteritis ...... Obstructive Diseases of Intestine Peritonitis ..... Ascites ...... Cirrhosis of Liver .... Jaundice and other Diseases of Liver Other Diseases of Digestive System . 6. Diseases of Lymphatic System. (e.g. of Lymphatics and of Spleen) . 7. Diseases of Glandlike Organs of Uncertain Use. (e.g. Bronchocele, Addison's Disease). 8. Diseases of Urinary System. Nephritis ..... Bright's Disease, Albuminuria . Disease of Bladder or of Prostate Other Diseases of the Urinary System 9. Diseases of Reproductive System. (a.) OF ORGANS OF GENERATION. Male Organs ..... Female Organs .... (J.) OF PARTURITION. Abortion, Miscarriage Puerperal Convulsions Placeflta pnevia, Flooding Other Accidents of Childbirth . 10. Diseases of Bones and Joints. Caries, Necrosis .... Arthritis, Ostitis, Periostitis . Other Diseases of Bones and Joints . 494 APPENDIX. 11. Diseases of Integumentary System. AGES. d H d ^02 oo H c 2^ 7 ^> ," ^ ^ 2 .a 1 00 1 1 oo o oo CO S I 1 1.8 1 1> 00 1 1 & ' .a oo 71 s ^ p_i d oo 7 1 1 a 00 1 00 71 1 oo l-H "8 g oo I-H | -s ' g ' ^ .X .-1 r i ri 1- J 1 H E M t> r* "^ ^ *C ^ * x . I rt .~ ~ "~""^ / ' ^~" .2 f. I en | Totals E WALES 2 K 498 APPENDIX. o ^ a! CO 3 02 I II sasuorauing -s-i : sSuipaaoojj ^8^ 'spaqsAi.00 pasuaorj osnjajj Joq^o pn^ i-eratuy ' -B^g 'guna jo suoi^inuinooy jo o^ papua^'B pu paAiaoai suoi^oiunraraoo jo -o& fBAoraa'a ^S 'SZ8Z '^OV ^I9H !tq'_ r r;uiiiiu' .... Kilogramme .... Myriogramme .... 0-015432 0'154323 1-543235 15-432349 154-323488 1543-234880 15432-348800 154323-488000 0-000032 0-000322 0-003215 0-032151 0-321507 3-215073 32-150727 321-507267 G'0000022 0-0000220 Q'0002205 0-0022046 0-0220462 0-2204621 2-2046213 22-0462126 1 Grain = 0-064798950 Gramm.-. 1 Ib. Avd. = '45359265 Kilogr. 1 Troy oz. = 31 '103496 Gramme. 1 Cwt. = 50 '80237689 Kilogr. 500 APPENDIX. XVII. LIST of APPARATUS and EE-AGENTS. The following sets of apparatus and re -agents mentioned in different parts of the work may be obtained from various manu- facturing chemists, such as Messrs. Griffin and Sons, Garrick Street, Covent Garden, London ; Messrs. Townson and Mercer, Bishopgate Street, London ; Messrs. Sutton, Norwich ; and Messrs. Harris and Co., Bull Ring, Birmingham. The prices quoted are of course sub-, ject to variation, and only approximately accurate : About Chemical Balance 3 15 Set of Gramme Weights, 50 Grammes to 1 Milli- gramme (Oertlings) . . . ". . 1150 For the Examination of Air. 1-1 Litre Measure graduated into c.c. . . .. 090 4 Glass Jars to hold 5000 c.c. each . . . 120 1 India-rubber Caps for ditto (double set) . . 1160 1 Tall narrow Glass, marked to measure 30 and 60 c.c. 023 1 Mohr's Burette 50 c.c. graduated into 1-1 Oth . 059 1 Support for ditto (Mahogany) . . . . 050 1 Bellows Pump with long nozzle (length sufficient to reach to the bottom of the jars) . . . . 04 2 Mixing Jars 1 Pint 02 6 Glass Stirrers for ditto 00 4 oz. Turmeric Paper ...... 1 Box of Filter Papers 02 1 Glass Funnel 4" 00 4 oz. Pure Cryst. Oxalic Acid . . . .01 1 Ib. Calcium Hydrate (for making lime water) . Oi 2 Common wet and dry bulb Thermometers (Mason's) each 090 For the Qualitative Examination of Water. 2 Tall colourless glass Cylinders 2 ft. high 1" diam. 10 1 Wide mouth colourless glass Flask to hold about 1000 c.c 010 1 Nest (12) of Test Tubes 016 1 Nest Porcelain Evaporating Basins, 2, 4, 8, and 16 oz. 036 1 Porcelain Crucible 2 J" diam 10 APPENDIX. 501 About 1 Set (6) Clark's Test Glasses 1 oz. . . .016 1 Set (6) Cylindrical Test Glasses 2 oz. . . . 020 Apparatus for making sulphuretted hydrogen water (pint) . . . . . . 050 6 oz. SoL Caustic Potash 021 6 ,, Ammonium Oxalate . . . . 1 10 6 Barium Nitrate 014 6 Silver Nitrate 034 6 ,, ,, Nessler's Test Solution . . . . 025 6 ,, Ammonia, strong . . . . . 014 6 Acetic Acid . . .- . . 024 6 Nitric Acid, dilute . . . . 0110 6 ,, ,, Sulphuric Acid, pure conctd. . . . 021 6 Hydrochloric Acid, dilute . . . 017 2 Potassium Iodide . . . . . 014 2 ,, Potassium Permanganate . . . . 014 6 ,, Ferrous Sulphide lumps . . . . 003 2 Sulphate 017 For t\e Quantitative Analysis of Water. Balance and Weights as above. 1 Liebig's Condenser with stand . . . . 0150 2 Eetorts, each 036 1 Retort Stand 070 2 Burettes 50 c.c., and graduated 1-1 Oth, each . 036 1 Burette 50 c.c., and graduated 1-1 Oth with glass stop-cock 076 2 Pipettes, 2 c.c., eacli 006 2 Pipettes, 5 c.c., graduated 1-1 Oth, each . . 016 2 Half-litre Flasks, each 016 2 Flasks to hold 70 c.c., each . . 010 2 Flasks to hold 35 c.c., each . ..006 6 Nessler Glasses, 50 c.c., each . . . . 016 1 Platinum Dish 400 1 Bunsen Burner 020 1 Wash-bottle 016 Nitrate of Silver, pure, per oz. . . . . 040 Permanganate of Potash . . . . 008 P. .lash .... 6 S..ap u->t (Clark's) per Ib 040 ut 060 Chloride of Ammonium per oz. . . . . 006 Cliromate of Potash 003 502 APPENDIX. For the Examination of Milk. About 1 Lactometer graduated to test approximately the percentage of adulteration with water (in a case) 3 1 Tall narrow glass vessel graduated to test percent- age of cream (in a case) INDEX. ABC process of sewage -purification, 338. Ablution -rooms, situation of, in hospitals, 266. Aeroscope, 135. Ague, production of, 79. Air, amount of, to be supplied in ventilation, 89. composition of, 63 effects of impure, 64. examination of, 122. impurities in, 64. movements of, in ventilation, 100 of hospitals, 72, 259. of sewers, 72. Air-bricks, 102. Air-flues, 119. Alkali works, injurious gases given off by, 78. Ambulance, 284, 461. Ammonia in air, 134. water, 185. Analysis of air, 121. water, 163. Anderson's process of sewage-purification, 340. Anemometer, 124. Anthrax, 55, 81. Aqueduct, construction of, 154. Archimedean-screw ventilator, 117. Arnott's ventilator, 112. Artisans' and Labourers' Dwellings Act, 450. Ash.'s. usr of, iii privies, 308, 321. Ashpits, 308, 311. B BAKKII it ion Act, 450. Barracks, ventilation of, 96. 504 INDEX. Basins, lavatory, 267. Baths, amount of water required for, 145. Baths and Washhouses Acts, 450. Bedding, disinfection of, 390. Bird's process of sewage-purification, 338. Birth-rate, 405. Black Death, 6. Blyth's process of sewage-purification, 337. Bone, amount of, in meat, 39. Braxy in sheep, 54. Bread, examination of, 45. Brickfields, effluvia arising from, 78. Bromine as a disinfectant, 385. Buildings, new, regulation of, 282, 449. Burnett's fluid as a disinfectant, 385. Butcher-meat, examination of, 42. Butter, examination of, 47. By-laws, subjects to which they apply, 451. CALCIUM chloride as a disinfectant, 387. Calorigen stove, 111. Carbolic acid as a disinfectant, 385. Carbon-filtration of sewage, 341. Carbonic acid, amount of, given off by the lungs, 66. ,, ,, in air, 63. determination of, in air, 127. physiological effects of, 68. Carriages for conveyance of infected persons, 284, 461. Catchment-basins, definition of, 140. Cellar-dwellings, regulation of, by law, 436. Census, how taken, 395. Cesspools, construction of, 234. dangers arising from, 74, 165, 252. Charcoal as a disinfectant, 383. filters, 160. ventilators, 296. Cheese, examination of, 47. Chemical works, injurious gases given off by, 78. Chicory, detection of, in coffee, 48. Chimneys, ventilation by, 106. Chloralum as a disinfectant, 387. Chloride of lime as a disinfectant, 387. zinc, 388. Chlorine as a disinfectant, 384, INDEX. 505 Cholera, prevention of, 369, 473. production of, by impure air, 75. ,, ,, ,, water, 204. Cisterns, cleansing of, 157, 167. construction of, 157. Clark's process of water-purification, 163. 'Climate, influence of, on public health, 425. Closets, ash, 311. earth, 316. dry, 318. pail, 310. trough, 305. tumbler, 305. water, 236, 304. Clothing, disinfection of, 390. Coffe.e, examination of, 11. Collecting water for analysis, 169. Common lodging-houses, 436. Conduits, construction of, for water-supply, 154. Condy's fluid as a disinfectant, 387. as a water-purifier, 163. Cooper's salts as a disinfectant, 388. Copper sulphate as a disinfectant, 387. Cottage hospitals, 269. Cowls, use of, in ventilation, 103. Cowsheds, regulation of, 459. Cubic space, necessary amount of, for requirements of health, 93. in hospitals, 262, 278. Cupralum as a disinfectant, 386. D DAIRIES, regulation of, 459. Death-rates, 406. Diarrhoea, production of, by impure air, 75, 381. ,, ,, impure water, 226. ,, ,, unwholesome food, 53. summer, 381 Dietaries, construction of, 38. of convicts, 36 of low-fed operatives, 35. of well-fed operatives, 36. Diphtheria, 60, 226, 379. Diseases, prevention of infectious, 362, 445, 473, 477. propagation of infectious, 369. traceable to sanitary defects, 248. 506 INDEX. Disinfectants, 382. Disinfecting-chamber, 280, 383, 391. Disinfection, 389, 477. Drains, house, construction of, 232, 294. Drain-sewers, construction of, 294. Dust-bins, construction of, 328. Dwellings, site, 229. sanitary inspection of, 248. structural details of, 231. unfit for habitation, 247, 437. Dysentery, production of, by impure water, 226. E EARTH closets, 316. Effluvia from decomposing animal matter, effects of, 77. from sewers and cesspools, effects of, 72. from offensive trades, 80, 86, 441. Eggs, examination of, 45. Enteric fever, prevention of, 372, 473, 477. production of, by impure air, 73. ,, by impure water, 208. ,, by pdlluted milk, 59. Epidemics, management of, 473. Ergot of rye, effects of, 52. Euthermic stove, 111. Excreta, composition of, 334. FATTY constituents of food, functions of, 29. Ferrous sulphate as a disinfectant, 388. Filter beds, 159. Filters, 160. Filth diseases, 249, 365. Filtration of sewage, 341. water, 159. Fireplaces, 106. Flour, examination of, 45.- Flues, foul air, 119, 239. Flushing of sewers, 298. Food, diseases connected with, 49. ' examination of, 42. functions and constituents of, 27. nutritive equivalents of, 31. Food and work, 32. Foods, preserved, 40. INDEX. 507 G GALTON'S stove, 109. Gas, combustion of, 93. Gas-lights, ventilation by, 116. Goitre, production of, by impure water, 200. Goux system of excretal removal, 310. Grates, 109. Graveyards, air of, 77. sanitary condition of, 429. H HEAT as a disinfectant, 383. Hille's process of sewage-purification, 339. Holden's 337. Hospitals, cottage, 269. for cases of infectious disease, 272, 445 pavilion, 260. rules for management of, 462. Houses, construction of, 231. damp, how prevented, 236. drainage of, 232. for the labouring classes, 240. Humidity of air, how ascertained, 135. Huts, hospital, 280. Hygiene of sick-room, 389. public, definition and scope of, 1. Hygrometers, use of, 136. INFECTIOUS diseases, origin of, 362. prevention of, 369, 449, 437. propagation of, 369. Inlets for fresh air, situation of, 118. Inoculation, 11. Inspectors of nuisances, duties of, 452. Intercepting tanks, 307. Intermittent downward filtration, 341. Intermittent fever, production of, 74, 201. Iodine as a disinfectant, 385. Irrigation, process of sewage, 343, 349. sanitary aspects of, 359. J JAIL-FEVER, 10. 508 INDEX. LAKES, quality of water from, 141. Latrines, construction of, 306. Lead acted on by water, 155. effects of, 201. Liebig's extract of meat, 40. Lieurnur's system of sewage -removal, 319. Life, expectation of, 417. Life-tables, 417. Lime process of sewage-purification, 337. Lodging-houses, 96, 436. Louvres, use of, in ventilation, 103. M M'DOUGALL'S disinfecting powder, 387. M'Kinnell's plan of ventilation, 105. Manurial value of sewage, 335. Marriage-rate, 406. Marshes, air of, 79. Measles, prevention of, 378. Meat, diseases produced by unwholesome, 49. examination of, 42, 445. preserved, 41. Medical officers of health, duties of, 421. Meteorology, 425. Middens, different plans of, 308. Milk, examination of, 46. preserved, 41. propagation of disease by means of, 58. shops, regulation of, 459. Mines, air of, 80. ventilation of, 115. Morbidity, 418. Mortality, 406. Mortuaries, 286. Moule's earth-closet, 316. N NITROGENOUS constituents of food, functions of, 27. Nitrous acid as a disinfectant, 384. Norton's tube- well, 150. Noxious trades and manufactures, 80, 441. Nuisances defined, 436. INDEX. 509 o OATMEAL, examination of, 46. Outlet tubes, construction of, 119. situation of, 119. Overcrowding, 438. Oxygen, amount of, in air, 63. Ozone, 64. P PAIL system of excretal removal, 310. Pavilion hospitals, 260. Phosphate process of sewage-purification, 238. Phthisis, production of, by impure air, 71. production of, by damp soil, 353. Pipes, water, 154. Pipe-sewers, advantages of, 293. Plagues, 6. Population, enumeration of, 395. estimates .of, 398. Potassium bichromate as a disinfectant, 388. Potatoes, examination of, 48. Potts' plan of ventilation, 104. Precipitation processes of sewage-purification, 336. Preserved meat, 41. milk, 41. vegetables, 41. Preventable disease, amount of, 20, Preventive measures, 369, 473, 477 Prisons, ventilation of, 114. Purification of sewage, 336. of water, 159. Q QUARANTINE, 446. R KAIN as a source of water-supply, 139. Rainfall, average amount of, 152. Rain-water, composition of, 139. Registration, 401. Relapsing fever, prevention of, 375, 477. production of, 51. Removal of sewage, 282. Reports, sanitary, how to write, 482. memorandum concerning, 480. 510 INDEX. Reservoirs, construction of, 152. Re-vaccination, necessity of, 471. Rickett's ventilating globe-light, 116. Ritchie's plan of ventilation, 113. River pollution, 332. River- water, quality of, 143. SACCHARINE constituents of food, functions of, 30. Saline matters, functions of, in food, 30. Sanitas, as a disinfectant, 387. Sausages, unwholesome, effects of, 53. Scarlet fever, prevention of, 377, 477. propagation of, 59, 377. Scavenging, 312, 327. Scott's, General, process of sewage-purification, 339. Scurvy, production of, 51. prevention of, 9, 51. Sewage, composition of, 334. effluvia, 72. filtration, 341. irrigation, 343. purification and utilisation of, 336. removal, 289. value of, 335. Sewers, construction of, 292. flushing of, 298. ventilation of, 295. Sheringham valve, use of, in ventilation, 102. Ships, hospital, 285. Shone's pneumatic system, 300. Shorland's grate, 109. Site, choice of, for hospitals, 259, 275. houses, 229. Slops, village, treatment of, 349. Smallpox, prevention of, 11, 375, 463, 477. Soils, influence of, on health, 353. Springs, quality of water from, 142. Stallard's plan of ventilation, 105. Statistics, vital, 394, 429, 487. Stoves, ventilating, 109. Streets, construction of, 330. Sulphurous acid gas as a disinfectant, 385. Subirrigation, 351., Sun-burners, use of, in ventilation, 116. INDEX. 511 Sweating sickness, 6. Sylvester's plan of ventilation, 103. Syphon filter, Bond's, 161. trap, 234. TANK, intercepting, Chesshire's, 307. Tank-filter, Crease's, 155. Tea, examination of, 48. Temperature, examination of air as regards, 135. 'IV nts. hospital, 280. Terebene as a disinfectant, 386. Thermometers, use of wet and dry bulb, 135. Tobin's system of ventilation, 102. Trades, unwholesome, 80, 441. Traps, 301. Trichina spiralis, disease produced by, 55. Trough-closets, 305. Tumbler-closets, 305. Typhoid fever, prevention of, 372, 473, 477. production of, by impure air, 73. ,, ,, polluted milk, 59. water, 208. Typhus fever, prevention of, 373, 477. production of, 70, 373. U T'RIXAI>. construction of, 308. Trine, amount and composition of, 334. Ttili/ation of sewage, 336. V\< CIVATIOX, rules for, ! Van Hecke's plan of ventilation, 117. Varley's ,, ,, 104. ,lles, preserved, 41. Ventilation, artificial, 106. natural, 99. of hospitals, 264, 278. of houses, 99, 239. of house-drains, 232. of mines, 80. of sewers, 295. of theatres, 118. of water- closets, 238. 512 INDEX. W WASTE-PREVENTERS, 157. Warming, 106. Water, amount of, derivable from rainfall, 152. analysis, 169. collection of, 169. distribution of, 154. effects of impure, 198. functions of, in food, 30. pollution of, 164. purification of, 159. qualities of, according to source, 144. quantity of, required for health and other purposes, 144. sources of, 139. Water-closets, situation and construction of, 236. Water-meters, 157. Waterworks, 150. Weare's process of sewage-purification, 318. Wells, 147. Whitthread's process of sewage-purification, 340. Whooping-cough, prevention of, 378. Windows, ventilation by, 101. Winds, action of, in ventilation, 99. Wool-sorters' disease, 81. Z ZINC chloride as a disinfectant, 388. Zymotic diseases, 362. THK KND. CATALOGUE No. 7. A CATALOGUE OF BOOKS FOR STUDENTS; INc I.I 1>IN<; A FULL LIST OF The ? Quiz-Coinpends ? AND MANY OF THE MOST PROMINENT Students' Manuals and Text-Books PUBLISHED BY 1'. BLAKISTON, SON & CO., Medical Booksellers, Importers and Publishers, No. 1012 WALNUT STREET, PHILADELPHIA. *** For sale by all Booksellers, or any book will be sent by mail, postpaid, upon receipt of price. Catalogues of books on all branches of Medicine, Dentistry, Pharmacy, etc., supplied upon application. THE PQUIZ-COMPENDS? A NEW SERIES OF COMPENDS FOR STUDENTS. For Use in the Quiz Class and when Preparing for Examinations. Price of Each, Bound in Cloth, $1.00 Interleaved, $1.25. Based on the most popular text-books, and on the lec- tures of prominent professors, they form a most complete set of manuals, containing information nowhere else collected in such a condensed, practical shape. The authors have had large experience as quiz masters and attaches of colleges, with exceptional opportunities for noting the most recent advances and methods. The arrangement of the subjects, illustrations, types, etc., are all of the most improved form, and the size of the books is such that they may be easily carried in the pocket. No. 1. ANATOMY. (Illustrated.) THIRD REVISED EDITION. A Compend of Human Anatomy. By SAMUEL O. L. POTTER, M.A., M.D., U. S. Army. With 63 Illustrations. " The work is reliable and complete, and just what the student needs in reviewing the subject for his examinations." The Physi- cian and Surgeon 's Investigator, Buffalo, N. Y. "To those desiring to post themselves hurriedly for examination, this little book will be useful in refreshing the memory." New Orleans Medical and Surgical Journal. " The arrangement is well calculated to facilitate accurate memo- rizing, and the illustrations are clear and good." North Carolina Medical Journal. Nos. 2 and 3. PRACTICE. A Compend of the Practice of Medicine, especially adapted to the use of Students. By DAN'L E. HUGHES, M.D., Demonstrator of Clinical Medicine in Jefferson Medical College, Philadelphia. In two parts. PART I. Continued, Eruptive, and Periodical Fevers, Diseases of the Stomach, Intestines, Peritoneum, Biliary Passages, Liver, Kidneys, etc., and General Diseases, etc. PART II. Diseases of the Respiratory System, Circu- latory System, and Nervous System ; Diseases of the Blood, etc. * # * These little books can be regarded as a full set of notes upon the Practice of Medicine, containing the THE ? QUIZ-COMPENDS ?. Synonyms, Definitions, Causes, Symptoms, Prognosis, Diagnosis, Treatment, etc., of each disease, and includ- ing a number of new prescriptions. They have been compiled from the lectures of prominent Professors, and reference has been made to the latest writings of Pro- fessors FLINT, DA COSTA, REYNOLDS, BARTHOI.OW, ROBERTS and others. " It is brief and concise, and at the same time possesses an accu- racy not generally found in compends." yas. M. French, M.D., Ass't to the Prof, of Practice, Medical College of Ohio, Cincinnati. " The book seems very concise, yet very comprehensive. . An unusually superior book." Dr. E. T. Bruen, Demonstrator of Clinical Medicine, University of Pennsylvania. " I have used it considerably in connection with my branches in the Quiz-class of the University of La." J. H. Bemiss, Neiv Orleans. " Dr. Hughes has prepared a very useful little book, and I shall take pleasure in advising my class to use it." Dr. George rV. Hall, Professor of Practice, St. Louis College of Physicians and Surgeons. No. 4. PHYSIOLOGY. A Compend of Human Physiology, adapted to the use of Students. By ALBERT P. BRUBAKER, M.D., De- monstrator of Physiology in Jefferson Medical College, Philadelphia. " Dr. Brubaker deserves the hearty thanks of medical students for his Compend of Physiology. He has arranged the fundamental and practical principles of the science in a peculiarly inviting and accessible manner. I have already introduced the work to my class." Maurice N. Miller, M.D., Instructor in Practical His- tology, formerly Demonstrator of Physiology, University City of New York. " 'Quiz-Compend' No. 4 is fully up to the high standard estab- lished by its predecessors of the same series." Medical Bulletin , Philadelphia. " I can recommend it as a valuable aid to the student." C. N. Ellin-wood, M.D., Professor of Physiology, Cooper Medical Col- '! Francisco. " Tliis is a well written little book." London Lancet. No. 5. OBSTETRICS. A Compend of Okstelries. For Physicians and Students. I'.y HENRY <',. LAMMS, M.I >., ProiVssor of Obstetrics and Diseases of Women, in Starling Medical College, Columbus. Illustrated. " We have no doubt that many students will find in it a most val- uable aid in preparing for examination." The American Journal of Obstetrics. " It is complete, accurate and scientific. The very best book of its kind 1 have seen." J. S. Kno.r, Af.D., Lecturer on Obstetrics, Rush Medical College, Chicago. Price of each Book, Cloth, $1.00. Interleaved for Notes, $1.29. THE ? QUIZ-COMPENDS ?. " I have been teaching in this department for many years, and am free to say that this will be the best assistant I ever had. It is ac- curate and comprehensive, but brief and pointed." Prof. P. D. Yost, St. Louis. No. 6. MATEBIA MEDIOA. Revised Ed. A Compend on Materia Medica and Therapeutics, with especial reference to the Physiological Actions of Drugs. For the use of Medical, Dental, and Pharma- ceutical Students and Practitioners. Based on the New Revision (Sixth) of the U. S. Pharmacopoeia, and in- cluding many unofficinal remedies. By SAMUEL O. L. Potter, M.A.,M.D., U. S. Army. " I have examined the little volume carefully, and find it just ach a book as I require in my private Quiz, and shall certainly re- commend it to my classes. Your Compends are all popular here in Washington." John E.Brackett, M.D., Professor of Materia Medica and Therapeutics, Howard Medical College, Washington. " Part of a series of small but valuable text-books. . . . While the work is, owing to its therapeutic contents, more useful to the medical student, the pharmaceutical student may derive much use- ful information from it." N. Y. Pharmaceutical Record. No. 7. CHEMISTRY. Revised Ed. A Compend of Chemistry. By G. MASON WARD, M.D., Demonstrator of Chemistry in Jefferson Medical Col- lege, Philadelphia. Including Table of Elements and various Analytical Tables. " Brief, but excellent. ... It will doubtless prove an admirable aid to the student, by fixing these facts in his memory. It is worthy the study of both medical and pharmaceutical students in this branch." Pharmaceutical Record, New York. No. 8. VISCERAL ANATOMY. A Compend of Visceral Anatomy. By SAMUEL O. L. POTTER, M.A., M.D., U. S. Army. With 40 Illustrations. *#* This is the only Compend that contains full descriptions of the viscera, and will, together with No. i of this series, form the only complete Compend of Anatomy published. No. 9. SURGERY. Illustrated. A Compend of Surgery; including Fractures, Wounds, Dislocations, Sprains, Amputations and other opera- tions, Inflammation, Suppuration, Ulcers, Syphilis, Tumors, Shock, etc. Diseases of the Spine, Ear, Eye, Bladder, Testicles, Anus, and other Surgical Diseases. By ORVILLE HORWITZ, A.M., M.D., with 43 Illustra- tions. Price of Each, Cloth, $1.00. Interleaved for Notes, $1.25. THE ?QUIZ-COMPENDS? No. 10. ORGANIC CHEMISTRY. JUST PUBLISHED. A Compend of Organic Chemistry, including Medical Chemistry, Urine Analysis, and the Analysis of Water, and Yood, etc. By HENRY LEFFMANN, M.D., Pro- fessor of Clinical Chemistry and Hygiene in the Phila- delphia Polyclinic ; Professor of Chemistry, Penn- sylvania College of Dental Surgery ; Member of the N. Y. Medico-Legal Society. Cloth. $1.00. Interleaved, for the addition of Notes, $1.25. Nature of Organic Bodies. Transformations under various con- ditions. Organic Synthesis. Homologous and Isomeric Bodies. Empirical and Rational formulae. Classification of organic bodies. Hydrocarbon. Derivatives of Hydrocarbons. Alcohols and Ethers. Benzenes and Turpenes. Fat Acids, Oils and Fats, Sugars, Gluco- sides. Cyanogen Compounds Amines and Amides. Alkaloids. Ptomaines. Animal Chemistry. Nutrition and Assimilation. Food, Water and Air. Urinary Analysis. Index. The Essentials of Pathology. BY D. TOD GILLIAM, M.D., Professor of Physiology in Starling Medical College, Columbus, O . With 47 Illustrations. 12mo. Cloth. Price $2.00. *** The object of this book is to unfold to the beginner the funda- mentals of pathology in a plain, practical way, and oy bringing them within easy comprehension to increase his interest in the study of the subject. Though it will not altogether supplant larger works, it will be found to impart clear-cut conceptions of the generally accepted doctrines of the day, and to prevent confusion in the mind of the student. A POCKET-BOOK >F PHYSICAL DIAGNOSIS OF Till: Diseases ofihe Heart and Lungs. A MANUAL FOR STUDENTS AND PHYSICIANS. BY DR. EDWARD T. BRUEN, Demonstrator of Clinical Medicine in the University of Pennsyl- vania, Assistant Physician to the University Hospital, etc. Second Edition, Revised. With new Illustrations. 12mo. $1.50. %*The subject is treated in a plain, practical manner, avoiding questions of historical or theoretical interest, and without laying special claim to originality of matter, the author has made a book that presents the somewhat difficult points of Physical Diagnosis clearly and distinctly. STUDENTS' MANUALS. TYSON, ON THE URINE. A Practical Guide to the Examination of Urine. For Physicians and Stu- dents. 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Col- ored Plate and other Illustrations. 32mo, cloth, .75 BEALE, ON SLIGHT AILMENTS. Their Na- ture and Treatment. By LIONEL S. BEALE, M.D., F.R.S. Second Edition. Revised, Enlarged and Illus- trated. 283 pages. 8vo. Paper covers, 75 cents; cloth, $1.25 ALLINGHAM, ON THE RECTUM. Fistulae, Hemorrhoids, Painful Ulcer, Stricture, Prolapsus, and other Diseases of the Rectum ; Their Diagnosis and Treatment. By WM. ALLINGHAM, M.D. Fourth Re- vised and Enlarged Edition. Illustrated. 8vo. Paper covers, 75 cents; cloth, $1.25 THOMPSON, ON THE URINARY ORGANS. On Diseases of the Urinary Organs. By SIR HENRY THOMPSON, M.D., F.R.C.S. Seventh Edition. 84 Illus- trations, 8vo, Paper covers, 75 cents; cloth, $1.25 STUDENTS' MANUALS. MARSHALL AND SMITH, ON THE URINE. The Chemical Analysis of the Urine. By JOHN MAR- SHALL, M.D., Chemical Laboratory, University of Penn- sylvania, and PROF. E. F. SMITH. Illus. Cloth, $i oo MEARS' PRACTICAL SURGERY. 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Recommended as a Text-book at University of Pennsylvania, Long Island College Hospital, Yale and Harvard Colleges, Bishop' s College, Montreal, University of Michigan, and over twenty other Medical Schools. A HANDBOOK OF THE THEORY AND PRACTICE OF MEDICINE. By FREDERICK T. ROBERTS, M.D., M.R.C.P., Professor of Clinical Medicine and Therapeutics in University College Hospital, London. Fifth Edition. Octavo. CLOTH, $5.00; LEATHEB, $6.00. *#* This new edition has been subjected to a careful revision. Many chapters have been rewritten. Important alterations and additions have been made throughout, and new illustrations intro- duced. "A clear, yet concise, scientific and practical work. It is a capi- tal compendium of the classified knowledge of the subject." Prof. J. Adams Allen, Rush Medical College, Chicago. " I have become thoroughly convinced of its great value, and have cordially recommended it to my class in Yale College." Prof. David P. Smith. " I have examined it with some care, and think it a good book, and shall take pleasure in mentioning it among the works which may properly be put in the hands of students." A. B. Palmer, Prof, of the Practice of Medicine, University of Michigan. " It is unsurpassed by any work, that has fallen into our hands, as a compendium for students preparing for examination. It is thoroughly practical, and fully up to the times." The Clinic. " Our opinion of it is one of almost unqualified praise. The style is clear, and the amount of useful and, indeed, indispensable information which it contains is marvelous." Boston Medical and Surgical Journal. RIDDLE'S MATERIA MEDICA. NINTH REVISED EDITION. Recommended as a Text-book at Yale College, University of Michigan, College of Physicians and Surgeons, Baltimore, Baltimore Medical College, Louisville Medical College, and a number of other Colleges throughout the U. S. ' BIDDLE'S MATERIA MEDICA. For the Use of Students and Physicians. By the late PROF. JOHN B. BIDDLE, M.D., Profes- sor of Materia Medica in Jefferson Medical College, Philadelphia. The Ninth Edition, thoroughly revised, and in many parts re- written, by his son, CLEMENT BIDDLE, M.D., Past Assistant Surgeon, U. S. Navy, assisted by HENRY MORKIS, M.D. CLOTH, $4.00 ; LEATHER, $4.75. " I shall unhesitatingly recommend it (the gth Edition) to my students at the BELLEVUE HOSPITAL MEDICAL COLLEGE. Prof. A. A. Smith, New York, June, 1883. " The standard ' Materia Medica with a large number of medi- cal students is Biddle's." Buffalo Medical and Surgical Journal. "The "larger works usually recommended as text-books in our medical schools are too voluminous for convenient use. This work will be found to contain in a condensed form all that is most valuable, and will supply students with a reliable guide." Chicago Med. Jl. *#* This Ninth Edition contains all the additions and changes in the U. S. Pharmacopoeia, Sixth Revision. STANDARD TEXT-BOOKS. 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HAWKES TANNER, M.D. REVISED AND ENLARGED BY DR. BROADBENT. Octavo, Cloth. Price $3.00. *#* The worth of a work of this kind, by so eminent a professor as Dr. Tanner, cannot be over-estimated. As an aid to physicians and druggists, both in the country and city, it must be invaluable. It contains a full list of all diseases, arranged in alphabetical order, with list of formulae, and appendix giving points of interest regard- ing health resorts, mineral waters, and information about cooking and preparing food, etc., for the invalid and convalescent. The page headings are so indexed that the reader is enabled to find at once the disease wanted ; its synonyms, classification, varie- ties, description, etc., with the course of treatment recommended by the best authorities, and is referred, by number, to the several prescriptions that have proved most efficacious. These prescrip- tions are also arranged so that they can be easily referred to, with directions how to use them, when to use them, and what diseases they are generally used in treating. The directions for cooking foods and preparing poultices, lotions, etc., are very full. The work will be found specially useful to students and young physicians. RICHTER'S CHEMISTRY, A TEXT-BOOK of INORGANIC CHEMISTRY for STUDENTS. By PROF. VICTOR von RICHTER, University of Breslau, AUTHORIZED TRANSLATION FROM THE THIRD GERMAN EDITION, By EDGAR F. SMITH, M.A., Ph.D., Professor of Chemistry in Wittenberg College, Springfield, Ohio: formerly in the Laboratories of the University of Pennsyl- vania ; Member of the Chemical Society of Berlin. 12mo. 89 Wood-cuts and Col. Lithographic Plate of Spectra. $2.00 In the chemical text-books of the present day, one of the striking features and difficulties we have to contend with is the separate presentation of the theories and facts of the science. These are usually taught apart, as if entirely independent of each other, and those experienced in teaching the subject know only too well the trouble encountered in attempting to get the student properly in- terested in the science and in bringing him to a clear comprehension of the same. In this work of PROF. VON RICHTER, which has been received abroad with such hearty welcome, two editions having been rapidly disposed of, theory and fact are brought close together, and their intimate relation clearly shown. From careful observa- tion of experiments and their results, the student is led to a correct understanding of the interesting principles of chemistry. The de- scriptions of the various inorganic substances are full, and embody the results of the latest discoveries. In preparation, "ORGANIC CHEMISTRY," By the same author. Translated. BYFORD, DISEASES OF WOMEN. NEW REVISED EDITION. The Practice of Medicine and Surgery, as applied to the Diseases of Women. By W. H. BYFORD, A.M., M.D., Professor of Gynaecology in Rush Medical College; of Obstetrics in the Woman's Medical College ; Sur- geon to the Woman's Hospital; President of the American Gynaecological Society, etc. Third Edition. Revised and Enlarged; much of it Rewritten; with over 1 60 Illustrations. Octavo. PRICE, CLOTH, $5.00; LEATHER, $6.00. " The treatise is as complete a one as the present state of our science will admit of being written. We commend it to the diligent study of every practitioner and student, as a work calculated to in- culcate sound principles and lead to enlightened practice." New York Medical Record. " The author is an experienced writer, an able teacher in his de- partment, and has embodied in the present work the results of a wide field of practical observation.. We have not had time to read its pages critically, but freely commend it to all our readers, as one of the niost valuable practical works issued from the American press." Chicago Medical Examiner. DAY ON CHILDREN. Second Edition. The Diseases of Children. A Practical and Systematic Treatise for Practitioners and Students. By WILLIAM 1 1 . DAY, M.D., Author of " Headaches ; Their Causes, Nature and Treatment ;" Member of the Royal College of Physicians of London ; Physician to the Samaritan Hospital for Women and Children, etc. Second Ed. Rewritten and very much Enlarged. 8vo. 752 pp. PRICE. CLOTH, $5.00: SHEEP, $6.00. " A careful examination of this book leads us to characteri/e it .is a plain, straightforward treatise on the subject upon which it treats . . . giving sound practical advice." Philad'a Med. Times. " ( >n the whole, we must confess we are pleased with this book and can heartily recommend it a recommendation which it does not appear to need, as it has already reached its second edition." American Journal of Medical Science. MACKENZIE, THE THROAT AND NOSE. l!y MOKKI.I. M.\( KI.N/.II.. M.D., Senior Physician to the Hospital for I )i -cases of the Chest and Throat ; Lecturer on Diseases of the Throat at the London Hospital, etc. VOL. I. Including the PHARYNX, LARYNX, TRACHEA, etc. 112 Illustrations. ( 'loth, 54.00 ; Leather, $5.00 VOL. II. DISEASES r im: HA<;US, NASAL CAVITIK* AND NKCK. Cloth, $3.00; Leather, $4,00 The two volumes at one time, Cloth. $6.00: Leather, $7.50 YEO'S PHYSIOLOGY. A MANUAL FOR STUDENTS. JUST READY. 300 CAREFULLY PRINTED ILLUSTRATIONS. FULL GLOSSARY AND INDEX. By GERALD F. YEO, M.D., F.R.C.S., Professor of Physi- ology in King's College, London. Small Octavo. 750 pages. Over 300 carefully printed Illustrations. PRICE, CLOTH, $4.00; LEATHER, $5.00. " By his excellent manual, Prof. Yeo has supplied a want which must have been felt by every teacher of physiology. * * * * In conclusion, we heartily congratulate Prof. Yeo on his work, which we can recommend to all those who wish to find within a moderate compass a reliable and pleasantly written exposition of all the essential facts of physiology as the science now stands." The Dublin Journal of Med. Science. "The work will take a high rank among the smaller text-books of Physiology." Prof. H. P. Bowditch, harvard Med. School, Boston. " The brief examination I have given it was so favorable that I placed it in the list of text-books recommended in the circular of the University Medical College." Prof. Lewis A. Stimpson, M. D., 37 East 33d Street, New York. " For students' use it is one of the very best text-books in Physi- ology." Prof. L. B. How, Dartmouth Med. College, Hanover, N. fft RINDFLEISCH. THE ELEMENTS OF PATHOLOGY. TRANSLATED BY WM. H. MERCUR, M.D. REVISED AND EDITED BY PROF. JAS. TYSON, Of the University of Pennsylvania. OCTAVO. CLOTH. NEARLY READY. *#.* It is the object of Prof. Rindfleisch to present in this volume of moderate size the fundamental principles of Pathology A large number of the general processes which underlie disease, a knowledge of which is essen- tial to the practical physician, are plainly presented. They include, among others, inflammation, tumor forma- tion, fever, derangements of nutrition, including atrophy, derangements of the movement of the blood, of blood formation and blood purification, hypenesthesia, anaesthe- sia, convulsions, paralysis, etc. The well-known reputa- tion of the author, his thorough familiarity with, and his method of treating the subject, make this most recent work peculiarly useful to the student, as well as to the prac- ticing physician who wishes to brush up his pathology. 14 DAY USE T DES * **OM WHICH BORROWED W7 LD 21-40m-4 '64 (E4555slO)476 . 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