LIBRARY Connecticut Agricultural College CLASSNO^ £}-l ^ COST DATE ^CU \' ci^ \ BOOK 6l3.P9q r 1 PVLE # -MANUAL OF PERSONAL HYGIENE 3 "liSa 000353^5 This book may be kept out TWO WEEKS and is subject to a fine of TWO CENTS a day thereafter. It will be due on the day indicated below. SZ61 " t^ AVW OCT t 8 193a ^ ^0^ 3 1933 yi A MANUAL OF ^(\ Personal Hygiene Proper Living upon a Physiologic Basis BY AMERICAN AUTHORS EDITED BY WALTER L. PYLE, A*M., M.a Late Member of the American Ophthalmological Society; Late Fellow of the College of Physicians of Philadelphia; Late Assistant Surgeon to the Wills Eye Hospital, Philadelphia, etc. CONTRIBUTORS D. H. BERGEY. M. D. WALTER L. PYLE. M. D. J. W. COURTNEY. M. D. B. ALEXANDER RANDALL. M. D. HOWARD FOX. M. D. G. N. STEWART, M. D. (Edin.) JOEL E. GOLDTHWAIT. M. D. CHARLES G. STOCKTON. M. D. E. FLETCHER INGALS, M. D. HARVEY W. WILEY. M. D. SEVENTH EDITION, REVISED AND ENLARGED PHILADELPHIA AND LONDON W. B. SAUNDERS COMPANY 1922. Copyright, 1900, by W. B. Saunders. Reprinted and recopyrighted May, 1901 . Revised, reprinted, and recopyrighted October, 1904. Reprinted September, 1905. Revised, reprinted, and recopyrighted March, 1907. Reprinted September, 1909. Re- vised, reprinted, and recopyrighted April, 1910. Reprinted May, 1911. Re- vised, reprinted, and recopyrighted August, 1912. Reprinted June, 1913, and March, 1914. Revised, reprinted, and recopyrighted May, 1915. Reprinted November, 1915, and September, 1916. Revised, reprinted, and recopyrighted August, 1917 / 34-^ X Copyright, 1917, by W. B. Saunders Company Reprinted March, 1918 Reprinted October, 1919 Reprinted March, 1920, and October, 1920 Reprinted January, 1921, and August, 1921 Reprinted November, 1922 PRESS OF W. B. SAUNDERS COMPANY PHILADELPHIA PREFACE. The object of this manual is to set forth plainly the best means of developing and maintaining physical and mental vigor. -Throughout the book there is concise but adequate discussion of the anatomy and physiology of the parts under consideration, upon which is based the subjoined advice. In other words, there is an exposition of proper living upon a physiologic basis. Purely technical phraseology has been avoided, as far as compatible with the scientific value of the text, and numerous explanatory diagrams and illUvStrations have been introduced. Although each special chapter is com- plete in itself, there has been purposive repetition of remarks upon subjects of such general interest as eating, drinking, breathing, bathing, sleep, exercise, etc., in order that they may be discussed more thoroughly from several standpoints. PREFACE TO THE SEVENTH EDITION. In response to a growing demand, through the several edi- tions, the work has been repeatedly revised, and from time to time numerous additions have been made. The present edition contains several new paragraphs of timely interest. WAIvTER L. PYLK. 193 1 Chestnut St., Philadelphia. INTRODUCTION.^ Strange as it may seem, the one subject which every fair-minded person admits should be taught thoroughly — namely, how to keep healthy — has been largely neglected. With all the recent agitation for educational reform, there remains, in a measure, the same indiflference to the proper teaching of the care of the body, regarding which Herbert Spencer lectured the pedagogic world over forty years ago. Mr. Spencer proved that knowledge may have in- trinsic value, and that the value of some knowledge must be greater than that of others. In our brief lives it is most necessary to distinguish and give precedence to the useful, real, and effective over the non-useful, conventional, and ornamental ; or, to use a Baconian phrase, "we must determine the relative value of knowledges." All knowledge passes into action, and that knowledge that leads men to better physical lives is a communal as well as an individual gain. Mr. Spencer says that, in the order of their importance, the leading kinds of activity which con- stitute human life are : I. Those activities which directly minister to self- preservation. * A considerable portion of this introductory chapter is from an ad- dress by the editor in opening the Symposium of the American Academy of Medicine, on the "Teaching of Hygiene in the Pubhc Schools," in Washington, D. C, May ii, 1903. V VI INTRODUCTION, 2. Those activities which, by securing the neces- saries of life, indirectly minister to self-preservation. 3. Those activities which have for their end the rearing and disciplining of offspring. 4. Those activities which are involved in the main- tenance of proper social and political relations. 5. Those miscellaneous activities which make up the leisure part of life, devoted to the gratification of the taste and feelings. In other words, a rational order of subordination is : Education which prepares for a direct self-preser- vation ; that which prepares for an indirect self-pres- ervation ; that which prepares for parenthood ; that which prepares for citizenship ; and that which pre- pares for miscellaneous refinements. It is stated with great emphasis that without doubt the actions and precautions which from moment to moment secure self-preservation are of primary im- portance ; and that, "as vigorous health and its accompanying high spirits are larger elements of happiness than any other things whatsoever, the teaching how to maintain them is a teaching that should yield in moment to no other whatever." Fortunately, knowledge subserving direct self-pres- ervation is largely provided for by nature. The com- mon animal instincts give warning against gross dan- gers. The inquisitive, timid, restless infant is chiefly concerned in hourly acquisition of the primitive facul- ties of coordination, estimation of distance, size, con- sistence, and weight, the avoidance of things likely to cause pain, the assimilation of food, etc. Through- out childhood and youth there is a further elaboration of these primal requisites. But more than this is INTRODUCTION. Vll necessary, for besides the inecliaiiical dangers, there are the evils following breaches of physiologic laws. Unfortunately, so profound is the innate ignorance of these laws of life that it is often not even known that our sensations are our natural and most trustworthy guides. The less evident but no less real dangers arising from the complexities of modern social life and the attendant evil habits are continually present, despite all innate instincts of warning. The per- nicious influence of improper food and bad air, the abuse of stimulants and narcotics, the modern dissi- pations and vices, etc., can be modified only by proper and timely education. It has been said that ''health is man's birthright ; that it is as natural to be well as to be born," and that from ignorance and transgres*sions of physiologic and hygienic laws arise most disease and tendency to disease. Yet to-day, so tardy has been the recog- nition of the importance of instruction in the funda- mental 'principles of applied physiology as a means to complete living, that a thoroughly well person after middle life is the exception in every com- munity. On every side we find chronic complaint, physical weakness, weariness, and overwhelming gloom, which might have been prevented by proper timely instruction. A striking example of the sacrifice of health from avoidable and preventable suffering is the great num- ber of physical and moral wrecks, the victims of the very prevalent habit of worry. So close are the rela- tions of the mind and the body that one of the most prolific sources of sufFeri ng is continuous worry, and one of the surest ways to restore health that is threatened viii INTRODUCTION. is to keep the mind cheerful and hopeful. Excessive ambition, misdirected energy, longing for the unattain- able, regret for the unalterable, anticipation of future happenings, lack of a sense of perspective, fretting over non-essentials, indecision, reopening of trouble- some questions already settled, avarice, selfishness, excessive emotions, uncontrolled passions, and the actual cultivation of the melancholic state, are some of the important causes of mental anguish and sub- sequent physical suffering that are not commonly associated with the baneful breaches of hygienic laws to be demonstrated by teachers of practical physiology. With those who are physically or men- tally defective we have the patience to reason and to make allowance for, but little sympathy or guidance is offered to the practically normal person who is gradually becoming the slave of a cultivated habit of worry, letting the minor trials and troubles of a day shut out much of the sunshine and happiness of life. The spiritual sin of worry and its utter futility should be made plain, but its association with chronic ill- health needs more discussion in both schools and churches. Observance of such teaching would do much to lessen the great American army of neu- rasthenics. Besides the individual suffering from preventable illness, time and money are ruthlessly wasted, com- mercial and artistic instincts are curtailed, good parenthood and citizenship are rendered impossible, appreciation of amusement is dulled, and, besides being immensely deteriorated, life is markedly short- ened. "Is it not clear," asks Mr. Spencer, "that the physical sins — partly our forefathers' and partly INTRODUCTION. IX our own — which produce this ill-health deduct more from complete living than anything else, and to a greater extent make life a failure and a burden in- stead of a benefaction and a pleasure?" Many cases of illness are preventable, and Mr. Huxley says we should look upon them as criminal. Illness following disobedience of physiologic laws should be regarded as the punitive result of repre- hensible conduct and not as a simple grievance. There is such a thing as physical morality and the preservation of health should be considered a sacred duty. Persons who treat their bodies as they please and transgress rules of personal hygiene of which they should have a definite understanding are physi- cal sinners, and they are not only committing a crime against themselves, but often against their dependents and future generations. Public hygiene may be enforced, but personal and domestic hygiene must be taught. No law can compel citizens in times of epidemics of typhoid fever or cholera to boil their drinking-water and cleanse food that is to be eaten without cooking, but persistent warnings from the health-authorities, pub- lic lectures, and literature from physicians, and news- paper and periodical discussion will be of the greatest service in combating the spread of disease. General sanitary improvement is dependent upon the intelli- gence of the community, as well as upon efficient health-officials, and one of the important duties of the latter should be to strengthen public confidence and disseminate more widely knowledge concerning public, domestic, and personal hygiene. It is not merely the teaching of the rules of hygiene X INTRODUCTION. that is needed, nor the ordinary course in school- physiology. Personal hygiene is applied physiology, and a proper understanding of certain elemental truths must be acquired before they can be applied. Knowl- edge of the normal functions of the body and the simple methods of keeping them in healthy action is the one thing that no educated person should be excused from possessing ; yet most of our children reach maturity without sufficient parental or scho- lastic instruction in many essential matters of health. Men and women who would be greatly chagrined to be corrected in the pronunciation of a popular foreign proper name, or who would resent as an insult any imputation as to their lack of general culture or learning, show not the slightest embarrassment at their ignorance of the common physiologic functions of digestion, circulation, respiration, etc. Persons of intelligence continually furnish thoughtless rec- ommendations of purely ''quack" remedies and un- scientific instruments and apparatus ; and advertise- ments of these articles may be seen in the best gen- eral and religious periodicals. Concerning the popular desire of the British Uni- versity patrons for the classic instruction, Mr. Spencer says : " While anxious that their sons should be well up in the superstitions of two thousand years ago, they care not that they should be taught anything about the structures and functions of their own bodies — nay, would even disapprove such instruc- tion. So overwhelming is the influence of estab- lished routine ! So terribly in our education does the ornamental override the useful !" Is this not a fairly applicable arraignment of not a few Ameri- INTRODUCTION. XI can parents — especially as to the danghter's educa- tion ? yet it is to the mothers of to-day that the regi- men of the nursery, the rearing- of children, the preparation of food, and the problems of domestic hygiene are largely left. The literature for the layman pertaining to personal hygiene is in great measure unsatisfactory and irre- sponsible. Many of the so-called "health books" are of very questionable authorship, often the com- pilation of a layman, perhaps an amateur pathologist, an inaccurate physiologist, a moralist 6f vague opin- ions, with, unfortunately, a tendency to cater to the prurient. Such books make hypochondriacs of their readers, and if they include advice as to self-treatment, they may do great harm. It is the duty of the pro- fessional author to stem and correct any morbid atti- tude of his readers, and not to add to it under the pretext of necessary explanation. In this connection may be aptly quoted the following abstract from a recent editorial in the British Medical Joitr77aI : "If we may speak for parents in the medical profession, it is impossible to suppose that wise fathers and mothers could desire to suggest to their sons or daughters either certain problems raised or in many cases the explanations proffered. There is a multitude of the best parents who think that their way is not made easier by the so-called moral reformer, but rather the reverse. And there are many of the most wholesome-minded boys and sweetest girls who hate him with a perfect hatred. The rest would probably do very well without him." Many of the so-called "school-physiologies" fall short of their purpose by an inadequate conception of Xll INTR on UC TION. the proper methods of teaching hygiene. Not uncom- monly they are filled with a mass of intricate and useless anatomic data, and abstruse and unsettled questions in physiology that can be of no possible aid to either teacher or pupil in the practical application of the principles of personal hygiene. It is of great importance to begin this teaching early, before habits of carelessness and indiflference to things hygienic are formed. For this reason the home and the primary schools are by all means the places where the ' ' gospel of health" should first be promulgated. If parents and teachers are given the proper literature from which to prepare their instruction, they can readily impart to very young children many of the most important lessons in practical hygiene — as, for in- stance, the principles of contagion and the advan- tages of cleanliness. Children more advanced may be taught by illustrated talks, without the necessity of text-book study, the salient principles of hygiene of digestion, proper breathing, the care of the eyes, ears, skin, etc., and these lessons may be so firmly im- pressed while the mind and character are in the developmental stage that they are never forgotten. Some idea of the far-reaching effects of a general adoption of these simple methods of instruction in the proper care of the body may be formed from the following editorial comment of a prominent maga- zine^ on the praiseworthy eSbrt of the Teacher's College of the Columbia University in New York city to train teachers " to teach health " : "It may not be extravagant to say that this same movement is of larger possible benefit than anything ^ World's Work, February, 1903. INTRODUCTION. xiii which has hitherto been done in the name of educa- tion, for if it should ever come to pass that every pupil in the public schools should be brought naturally to a proper understanding of health and its relations to every other part of life and conduct, such a chance for the advancement of the human race would be given as no considerable section of society has yet ever had. If all easily preventable physical troubles were prevented, such an addition would be made to the energy and the good sense of the people as defies description. A merely incidental item of such social progress would be the incalculable saving of the money spent on quackery, and of the waste of energy that quackery causes." In view of the great importance of personal and domestic hygiene and the deficient popular instruction in the prevention of disease, a glorious opportunity awaits the philanthropist who will devote his energy and fortune to this teaching by public lectures and the dissemination of authoritative literature through every State in the Union. In literature and lectures on hygienic subjects too often the science is made too popular, or the popular exposition too scientific. There has also been too frequently a tendency to present as much of the "gospel of health" as may be put in popular form, or that, for ulterior motives, the layman may be in- duced to accept. Such attitude can only weaken the cause of preventive medicine among intelligent per- sons. It is not desirable to produce athletes, physical- culture fanatics, or practitioners of new-fangled and erratic ''systems" and "pathies." What is needed is simple instruction by capable teachers in the proper xiv INTRODUCTION. care and use of the body, authoritatively based upon the best available modern anatomic, physiologic, and hygienic data. We should not have "every man his own physician," as seems often the object in lectures, periodicals, and books relating to health ; rather give every man fundamental knowledge that will enable him to understand, and, if necessary, formulate, the requisite rules of health, and to distinguish scientific medicine from quackery. Stripped of its superfluous technicalities, this knowledge may be imparted to any one of average intelligence and education, and it is desirable that more literature and personal explana- tion in this direction should come from the American medical profession. The subject is much too impor- tant to be left entirely in the hands of lay teachers and writers. TABLE OF CONTENTS. HYGIENE OF THE DIGESTIVE APPARATUS. By Chas. G. Stockton, M. D., of Buffalo, Professor of Medicine in the Medical Department of the University of Buffalo. Physiology of Digestion, 9 — Mastication and insalivation, 9 — The stomach, 1 1 — The small intestine, 13 — Accessory digestive organs, 15 — The large intestine, 16 — Hygiene of the Teeth, 17 — Deformities, 17 — Causes of decay, 20 — Preservation, 24 — Tooth-brushes, 24 — Tooth-powder, 25 — Importance of teeth in digestion, 26 — Hygiene of the Gastro-intestinal tract, 26 — The appetite, 26 — The effect of mind on nutrition, 28 — The effect of eye-strain on nutrition, 29 — Regulation of meals, 31 — Regulation of diet, 33 — Proper cooking, 36 — Fruits, 37 — Coffee, tea, and cocoa, 37 — Sugar, 38 — Fats and oils, 38 — Drinking-water, 40 — Alcoholic beverages, 41 — Other stimulants, 42 — Eating after bathing, 43 — Eating after exercise, 44 — Influence of carriage and dress on digestion, 45 — Constipation and diarrhea, 48. HYGIENE OF THE SKIN AND ITS APPENDAGES. By Howard Fox, M. D., of New York, Clinical Professor of Dermatology, New York Polyclinic Medical School. Anatomy and Physiology, 52 — The epidermis, 52 — The derma, 54 — The perspiratory glands, 54 — The sebaceous glands, 57 — The hair, 58 — The nails, 60 — Bathing, 60 — The cold bath, 61 — The warm •bath, 63 — The hot bath. 64 — The proper time to bathe, 64 — Soap, 65 — Medicated soaps, 66 — Sea-bathing, 66 — The Turkish bath, 67 — The Russian bath, 69 — Bath-pruritus, 69 — Care of the complexion, 70 — Clothing, 72 — For cold weather, 74 — For warm weather, 75 — Underclothing, 75 — Macintoshes, 76 — Shoes, 76 — Socks and stock- ings, 79 — Garters, 79 — Corsets, 80 — Bed-clothing, 81 — Care of the Hair, 82 — Dandruff, 82 — Hair-brushes, 83 — Combs, 83 — Shampoo- ing, 84 — Head-gear, 86 — Massage of the scalp, 87 — Cutting the hair, 88 — Dressing the hair, 89 — "Hair- restorers," 89 — Removal of super- fluous hairs, 90 — Hair-dyes, 91 — Care of the beard, 91 — Shaving, 92 — Care of the nails, 92. I 2 TABLE OF CONTENTS. HYGIENE OF THE VOCAL AND RESPIRATORY APPARATUS. By E. Fletcher Ingai 257 — Effects of smoking and drinking, 257 — Moving pictures, 258 — Relation of the eyes to the general health, 258 — Spectacles and Eye-glasses, 259 — Invention, 259 — Province of the optician, 259 — Spectacles, 261 — Fitting and care, 262 Circular lenses, 264 — Toric lenses, 265 — Eye-glasses, 267 — Oxford eye-glasses, 267 — Bifocal lenses, 267 — Trifocals, 269 — Pantoscopic spectacles, 269 — Lorgnettes, 270 — Tinted glasses, 270 — Prejudice against wearing glasses, 271 — Early discomfort, 273 — Necessity of changing, 275 — Artificial eyes, 275. HYGIENE OF THE BRAIN AND NERVOUS SYSTEM. By J. W. Courtney, M. D., of Boston, Physician for Diseases of the Nervous System, Boston Ci y Hospital. General Principles, 277 — Nervous tissue, 277 — The central nervous system, 277 — Analogy to telegraphy, 277 — Influences of heredity, education, and environment, 278 — "Bom degenerate," 278 — Pre- natal influences, 280 — Nervous and mental hygiene in childhood, 281 — The school-going age, 281 — After the age of twelve, 2S2 — Puberty 4 TABLE OF CONTENTS. and its attendant dangers, 282 — Duties of parents and teachers, 283 — Neurasthenia, 284 — General remarks, 284. — Definition, 285 — Cau- sation, 285 — Symptoms, 287 — Pathology, 291 — Prognosis, 292 — Hygienic treatment, 292 — Abuse of alcohol, coffee, tea, and tobacco, 293 — Overwork, 295 — "Curve of health," 295 — Mental overwork, 296 — Worry, 299 — Need of mental recreation, 300 — Physical over- work, 302 — Regulated exercise, 306 — Golf, 307 — Bicycling, 308 — Tennis, 308 — Canoeing and boating, 309 — Hunting, 309 — Sleep, 310 — Physiologic considerations, 310 — Insomnia, 313 — Treatment, 314 — Conclusion, 316. PHYSICAL EXERCISE. By G. N. Stewart, M. D. (Edin.), of Ci.eveland, Professor of Experimental Medicine in Medical Department of Western Reserve Uni- versity, Cleveland. Physiology of Muscular Movement, 317 — Spontaneous move- ment, 317 — The muscles, 317 — Skeletal muscles, 318— Striped muscles, 318 — Unstriped muscles, 318 — Muscular contraction, 318 — Nerve-impulse, 319 — Voluntary movements, 321 — Automatic move- ments, 321 — Reflex movements, 322 — Work done by muscular con- traction, 322 — Transformation of food-substances into muscular energy, 323 — Comsumption of glucose, 324 — Consumption of glyco- gen, 324 — The nitrogenous substances, 324 — The Effects of Muscular Exercise, 325 — Fatigue of muscles, 325 — Restorative properties of food-substances, 327 — Sugar, 327 — Fats, 327 — Caffein, 327— Alcohol, 328 — Production of waste-substances, 328 — Effect of muscular con- traction on the flow of blood, 328 — Effect of exercise on the heart, 329 — On respiration, 330 — On the skin, 331 — On the digestive system, 331 — Physical Training, 331 — Association with mental training, 331 — Kind of exercise most advantageous, 333 — Physical training in childhood, 334 — In youth, 335— In adult life, 335— Sports and gym- nastics, 336 — "Swedish movements," 337 — Amount of exercise re- quired, 337 — Excessive exercise, 338 — Exercise in disease, 339 — Home Gymnastics, 340 — Importance of gymnastics, 340 — Training of the abdominal muscles, 341 — General rules for exercises, 341 — Stretching exercises, 343 — Dumb-bell exercise, 343 — Breathing exer- cise, 344 — Twisting exercise, 345 — Shrug-movement, 346 — Forward and backward bend, 346 — Side bend, 347 — Windmill movements, 347 —Floor-exercises, 348 — Relaxing exercises, 349 — Knee, 349— Hip, 349 — Shoulders, 349. TABLE OF CONTENTS. 5 THE BODY-POSTURE. By Joel E. Goldthwait, M. D., of Boston. Imperfect Use of the Human Body as the Cause of Many Cases of Chronic Invalidism, 351 — Proper Poise of the Body, 351 — The Trunk as Cage in Which Body Organs are Placed, 353 — Erect Standing Posture, 353 — Flat Foot, 355 — Bending the Knee, 355 — Forward Drooping of Shoulders, 356 — Muscle Straining in Stoop or Round Shoulder, 356 — Diameter Through the Chest, 357 — Expansion of the Lungs, 357 — Heart Action, 358 — Displacements of Stomach, Intes- tines, Liver, and Kidneys, 358 — Constipation and Indigestion, 358 — Abdominal Pains, 358 — Circulation of the Spinal Cord, 358 — Ner- vous Weakness and Nervous Indigestion, 358 — Sitting, Rising, Walk- ing, Stooping, and Lying Postures, 358 — Slouching or Slumping Postures, 359 — Occupations, 360 — Drooping of Shoulders in Child- hood, 360 — Underwaist, 360 — Stocking-straps, 360 — "Angel-wing" Child, 362 — Round-shoulder in Adults, 362 — Posture of Fatigue, 362 — Mechanical Support, 362 — Sacro-iliac Joints, 362 — Backache, 363 — Leg-pains, 363 — Growing Pains, 363 — Standing with Hands in Pockets, 363 — Bad Habits in Sitting, 364 — Excessive Deposits of Fat, 364 — Large Abdomen, 364 — Effect of Trunk Muscles on Circula- tion of Spinal Cord, 365 — Nervous Prostration, 365 — Interdepend- ence of Body, Mind, and Spirit, 365. DOMESTIC HYGIENE. By D. H. Bergey, M. D., of PhiIvAdelphia, First Assistant in the Laboratory of Hygiene and Assistant Professor of Hygiene and Bacteriology in the University of Pennsylvania. General Remarks, 367 — Construction and Location of Dwell- ings, 368 — Location, 368 — Elevation, 368 — Southern exposure, 368 — Foundation and walls, 369 — Roof, 370 — Internal arrangement, 370 — Height, 370 — Size of rooms, 370 — Cellar, 371 — Kitchen, 372 — Re- frigerator, 372 — Mechanical and chemical cooling apparatus, 372 — Stairways, 372 — Hallways, 372 — Draperies, 372 — Curtains, 372 — Doors, 373 — Windows, 373 — Walls and wall-coverings, 373 — Floors and floor-coverings, 274 — ^Ventilation, 375 — Principal changes in air of dwellings, 376 — Relative proportion of carbon dioxid, 376 — Meth- ods of estimating, 376 — Odor of organic matter, 377 — Excess of humidity, 378 — Hygrometer, 378 — Natural ventilation, 379 — Arti- 6 TABLE OF CONTENTS. ficial ventilation, 380 — Ventilation of bed-rooms, 380 — Heating, 381 — Direct and indirect, 381 — Combined system of ventilation and heating, 381 — Fm-nace-heating, 381 — Excessive temperature, 383 — Dryness of the air, 383 — Dust, 383 — Devices for cooling the air, 384 — Water-supply, 385 — Purity, 385 — Municipal water-works, 386 — Filtration, 387 — Domestic filters, 387 — Pure water, 388 — Plumbing and Drainage, 389 — Sewers and drains, 389 — Traps, 390 — Waste- pipes, 390 — Sewer-gas, 391 — Cess-pools, 391 — Modem Bath-rooms andToilet-rooms,393 — Water-closets, 393 — Flush tanks,^393 — Water- waste preventers, 393 — Disposal of Garbage and Ashes, 394 — Gar- bage, 394 — Ashes, 395 — Nuisances, 395 — Foul odors, 395 — Noxious fumes, 396 — Noises, 396 — Dust, 396 — Smoke and soot, 397 — House- cleaning, 398 — Sweeping, 399 — Vacuum cleaners, 399 — Purifying agents, 399 — Washing and laundering, 400 — Clothes-cleaning, 401 — Clothes-disinfection, 401 — Food and Dietetics, 402 — Nutritive value and cost of foods, 403 — Vegetarian diet, 405 — Cooking, 405 — Adul- teration of foods, 405 — Preservation of food, 406 — Refrigeration, 406 — Chemical preservatives, 406 — Food as a cause of infectious dis- eases, 406 — Inspection of meats, 407 — Inspection of milk, 408 — Pas- teurized milk, 410 — Causes and Transmission of Disease, 410 — Physical causes, 410 — Vital causes, 410 — Chemic causes, 410 — Transmission of infectious diseases, 410 — Insects and vermin, 411 — Isolation and disinfection, 413 — Individual susceptibility, 414 — Environment, 414 — Heredity, 414 — Hygiene of the sick-room, 415 — House quarantine, 416 — Period of detention, 416 — Special precau- tions against typhoid fever, 417 — Typhoid vaccination, 420 — Small- pox, 420 — Diphtheria, 422 — Scarlet fever, 423 — Infantile paralysis (anterior poliomyelitis), 424 — Control of anterior poliomyelitis, 426 — Grip and pneumonia, 429 — Cold in the head, 429. FOOD— ADULTERATION AND DETERIORATION. By Harvey W. Wiley, M.D., of Washington, D. C, President of the United States Pharmaceutical Convention; former Chief of the Bureau of Chemistry, Department of Agriculture. Care of Food, 431— Shelves, 432— Ice-chest, 432— Foods are adul- terated, 433 — Fish foods, 433 — So-called smoked fish, 434— Oysters, 434— Poultry, 434 — Eggs, 435— Preserved meats, 436— Lards,'437 — Halphen test for cottonseed oil, 438 — Bechi or silver nitrate test for cottonseed oil, 438 — Beef-extract, 438 — Meat-powders, 43 9 — Gelatin, TABLE OF CONTENTS. 7 439 — Milk and milk products and oleomargarin, 440 — Butter, 442 — Oleomargarin, 442 — Cheese, 443 — Preparation of casein, 443 — Cereal foods, 444 — Cakes, 445 — Baking powder, 445 — Canned vegetables, 446 — Vegetable oils, 448 — Vegetable fats, 449 — Condiments, 449 Sugar, 450 — Confectionery, 451 — Mince meat and pie-fillers, 451 — Fruits, 452 — Canned fruits, 452 — Fruit syrups, 453 — Jams, jellies, marmalades, and preserves, 453 — Mush-rooms, 454 — Ice, 455 — Simple Tests of Adulterations, 457 — Gross physical adulterations, 457 — Coloring materials, 457 — Preservatives, 457 — Reagents, 457— Tests for detecting chemical preservatives, 458 — Tests of artificial coloring, 460 — Detection of Some Common Adulterants, 461 — Ex- amination of Certain Foods, 463 — Coffee, 463 — Water test for coffee, 463 — Canned goods, 464 — Eggs, 464 — Flavoring extracts, 465 — Flour, 466 — Vinegar, 466 — Butter, 466 — Watered milk, 467 — Gelatin in ice cream, 467 — Habit-forming drugs, 467. THE HYGIENE OF INFANCY. The Nursery, 470 — Foul air, 470 — Bed-clothes, 471 — Furnishings, 471 — Best bed for baby, 471 — Night-lamp, 472 — Closets, 472 — Sleep, 473 — Regularity, 473 — Nursing, 473 — Night-feedings, 473 — Bed-clothes fasteners, 474— Bathing, 474— Toilet articles, 474— The bath, 475— The bath-tub, 477— Daily bath habit, 477— Regularity of bath, 479— Exercise, 479— Outings, 480— Perambulator, 481— Trainmg of bladder and bowel muscles, 481 — Clothing, 481 — Ab- dominal band, 482 — Diapers, 482 — Socks, 483 — Clothing, 484 — Dressing the baby, 485 — Dressing the cord, 485— Out-of-door gar- ments, 485 — Layette, 486 — Time for wearing short clothes, 486 — Food, 487 — Mother's milk, 487 — Regularity in nursing, 487 — In- creasing mother's milk, 488— Nipples, 488— Weaning, 488— Arti- ficial Feeding, 489 — Artificial mother's milk, 489 — Preparation of food, 489 — Pasteurization, 489 — Heating milk, 490 — Pacifiers, 490 — Diet after weaning, 491— Care of the Baby in Summer, 492 — The Sick Baby, 492. APPENDIX. Pulse, Temperature, and Respiration, 495— Pulse, 495 — Tempera- ture, 496 — Clinical thermometer, 496 — Respiration, 497 — Baths, 497 — Temperature, 497— Hot-baths, 497— Hot foot-baths, 498 — Hot- 8 TABLE OF CONTENTS. vapor baths, 498 — Hot-air bath, 499 — Acid steam-bath, 500 — Sheet- bath, 500 — Drip-sheet, 500 — Cold douche, 501 — Cold pack, 501 — Hot pack, 501 — Partial packs, 502 — Massage, 503 — Movements, 503 — Method, 504 — Accidents and Emergencies, 505 — Cut and incised wounds, 505 — Lacerated wounds, 506 — Punctured wounds, 506 — Fish-hook wounds, 506 — Splinters, 507 — Insect-stings, 507 — Mos- quito-bites, 507 — Dog-bites, 507 — Snake-bites, 507 — Ivy-poisoning, 508 — Bruises and contusions, 508 — Sprains, 508 — Fractures, 509 — Dislocations, 509 — Handkerchief -bandages, 509 — Four- tailed ban- dages, 509 — Many-tailed bandages, 510 — Biu-ns and scalds, 510 — Household conflagrations, 511 — Inhalation of steam, 512 — Frost-bite and freezing, 514 — Sunstroke, 514 — Heat-exhaustion, 514 — Light- ning-stroke, 515 — Electrical injuries, 515 — Electric shock, 515 — Faint- ing, 515 — Drowning, 515 — Method of resuscitation, 516 — Simple ap- paratus, 516 — Oxygen, 516 — Cardiac massage, 516 — Epinephrin, 516 — Saline solution, 516 — Artificial respiration, 516 — Asphyxiation, 518 — Pulmotor, 5 1 9 — Resuscitation from mine-gases, 5 1 8 — Manual meth- ods, 518 — Prone-pressure method, 519 — Carbon monoxid poisoning, 519 — Mechanical devices for artificial respiration, 519 — Head-acci- dents, 51*9 — Epileptic convulsions, 520 — Convulsions in children, 520 — Hemorrhage of lungs, 520 — Bleeding from the stomach, 520 — Nose-bleed, 521 — Poisoning, 521 — Household poisons, 521 — First treatment, 521 — Stomach-pump, 522 — Irritant poisons, 522 — ^Acids and alkalis, 522 — Narcotics, 523 — Opium-poisoning, 523 — Bella- donna, 523 — Alcohol, 524 — Prussic acid, 524 — Strychnin, 524 — Rat-poison, 524 — Table of Poisons and Antidotes, 525. Glossary 527 Index 537 A MANUAL OF PERSONAL HYGIENE. HYGIENE OF THE DIGESTIVE APPARATUS- By CHARLES G. STOCKTON, M. D., OF BUFFALO. Professor of Medicine in the Medical Department of the University of Buf- falo ; Attending Physician to the Buffalo General Hospital. PHYSIOLOGY OF DIGESTION. Mastication and Insalivation. — Digestion begins in the mouth with the mastication and insalivation of the food. Upon the thoroughness of the mastica- tion, the disintegration of the larger and more resist- ing morsels and the thorough admixture of them with the saliva, depends in no small degree the comfort with which the gastric digestion is carried out. Starchy foods in particular require the effect of the ptyalin, a constituent of the saliva, by the action of which the starch, especially when thoroughly cooked, is converted into maltose. The saliva escapes into the mouth from three separate sets of salivary glands — the parotid at the angle of the jaw, the submaxil- lary along the side of the tongue, and the sublingual under the tongue. The mouth is further moistened by the secretion of the mucous membrane with which it is lined. The salivary secretion is excited by the presence of foreign bodies in the mouth, but especi- ally by food. The action of the glands is controlled 9 lO THE DIGESTIVE APPARATUS. by the nervous system, and the effect of the higher nervous centers upon their activity may be instanced in the free flow of saliva that follows the odor of cer- Nose Sahvarv "^ glands C^ f Trachea 1 1 Salivary {Parotid) gland Duoden Large intes- tine Small intes' tine ,, ^^ Rectum Vermiform appendi Fig. I. — General scheme of the digestive tract, with the chief glands open- ing into it. tain substances, and the sight, or even thought, of others. The saliva is slightly alkaline in reaction, and its activity differs in different individuals. THE STOMACH. II The conversion of starch into maltose by ptyalin is diminished in the presence of a slightly acid medium, and ceases in a free acid medium. If the saliva is di- luted by water or other fluids, its activity is correspond- ingly diminished. Therefore foods should only be swallowed after they are thoroughly disintegrated by the teeth and sufficiently liquefied by the saliva to pass easily through the esophagus without the assist- ance of drink. The stomach is a muscular sac, lying for the most part on the left side of the body and under the ribs. Its entrance, at the termination of the esophagus, is called the cardia, and is guarded by an increase in the circular muscle-fibers, by the contraction of which the opening is closed at the proper interval. Its out- let into the duodenum is called the pylorus, and this also is guarded by circular muscle-fibers, which close the opening so as to prevent the untimely escape of the gastric contents. The stomach is covered with a delicate serous coat, a part of the peritoneum, and is lined with a mucous membrane. In the adult the stomach, when filled, contains from two to three pints or more. It varies considerably in size and shape in healthy individuals. It is very richly sup- plied with blood-vessels and lymphatics; and the veins empty into the portal system going to the liver, not communicating directly with the general circula- tion. The mucous membrane secretes large quanti- ties of fluid called gastric juice, which contains hydrochloric acid, and two ferments called, respec- tively, pepsin and rennin, or lab-ferment. The acid is mostly secreted toward the cardiac end of the stom- ach and the ferments near the pyloric end. During 12 THE DIGESTIVE APPARATUS. fasting the stomach is of a pale-pink color, and con- tains a small amount of fluid neutral in reaction. With the introduction of food the mucous membrane becomes of a deeper red color and the secretion be- comes very abundant. As this secretion is acid in reaction, it might be supposed that the digestion of starch, begun in the mouth, would immediately cease in the stomach. Such, however, is not the case, owing to the fact that the earlier secretion of hydro- chloric acid promptly combines with the albumin in the foods, so that free hydrochloric acid is for a time not present. A slight amount of lactic acid is found at this time; but it mostly comes preformed in the food, and is not the result of secretion, although to some extent it may come from fermentation even in the healthy stomach. After a certain period of time, varying in individuals from a few minutes to a few hours, the secretion of hydrochloric acid is in excess of that which may combine with the albumin; and it therefore appears as a free acid, at which time the trace of lactic acid disappears. As a result of the in- creased acidity, the digestion of starches, for the time being, comes to an end. On the other hand, the so- lution of the albumins, their conversion into peptones, and the breaking up of the covering of the fat-cells proceed rapidly. The cellulose of vegetables and fruits is broken up, and the absorption of certain con- stituents of the stomach-contents begins. All of these matters are greatly favored by the muscular action of the stomach, which by slow wave-like contractions (the cardia and the pylorus being closed) thoroughly mingle the gastric contents and assist in their solution and absorption. From time to time THE SMALL LNTESTINE. 1 3 the better digested portions pass through the pylorus; but the solid particles stimulate pyloric contraction, and their escape into the intestine is therefore properly prevented. After the lapse of from four to seven hours the gastric digestion is practically com- pleted, the organ having gradually emptied itself, and at length the pylorus relaxes sufficiently to allow the more insoluble remains to pass into the intestine. Absorption from the stomach is of less impor- tance than was formerly supposed. The alcohols, salts, certain extractive matters, and pure water may be, and to some extent usually are, absorbed directly from the stomach; but water in the presence of solid foods or blended with foods, as in soup, is apparently not so absorbed. A glassful of pure water is found to have left the stomach after a quarter or half of an hour, but when taken with food it escapes with the latter in the ordinary course of digestion. The office of the stomach, like that of the mouth, is to prepare the food for its final digestion in the intestine. The stomach has a very complex nerve-supply that gov- erns its activity, and it is therefore subject to derange- ments that follow nervous excitation in various other parts of the organism. The Small Intestine. — The intestine is described as consisting of two divisions, a small and a large in- testine. The small intestine is about twenty feet long in the adult, and is subdivided into three portions: the duodenum, extending from eight to ten inches beyond the pylorus; the jejunum, which forms two- fifths; and- the ileum, three-fifths of the remainder of the small intestine. Like the stomach, the intestine is lined by a mucous membrane, with columnar epithe- 14 THE DIGESTIVE APPARATUS. Hum, and thickly set with secreting glands. It has a very vascular submucosa and is rich in lymphatics. A muscular coat arranged partly in circular and partly in longitudinal fibers lies outside of the submucosa. Finally, like the stomach, it is clothed with a serous membrane continuous with the lining of the peritoneal cavity. Between the muscular coats is arranged a system of fine nerves (Auerbach's plexus) which preside over the movements of the intestine. In the submucous coats, extending from the stomach to the anus, are distributed the fibers of the nerves of se- cretion (Meissner's plexus). These nerves are pro- vided with ganglion-cells, and it is probable that these are the centers that control the circulation, excretion, and secretion of the intestine. The surface of the mucous membrane of the stomach is enormously increased through the presence of the valvulae con- niventes and the villi. The former appear as nu- merous transverse folds projecting into the lumen of the intestine, and they interrupt and retard the cur- rent of the intestinal stream. Like other portions of the intestinal mucous membrane, they are covered with villi, one or two lines in length, so closely ar- ranged that they project from the surface somewhat in the manner of fur. Between the villi are placed three kinds of glands differing somewhat in character and distribution. The tubular depressions of the mucous membrane, called the glands of Lieberkuhn, extend throughout both the large and small intestines, in- creasing in size as they approach the anus. Brun- ner's glands are confined to the duodenum. They are placed in the submucosa and have excretory ducts; in structure and function they resemble the pyloric DIGESTION IN THE INTESTINE. 1 5 glands of the stomach. The glands of Peyer occur in the small intestine, but are most abundant in the lower portion of the ileum. Sometimes they are single, sometimes in clusters, when they are termed " agminate " glands, or Peyer' s patches. Accessory Digestive Organs. — The liver occupies a position on the right side of the body closely corre- sponding to that occupied by the stomach on the left. It moves with the diaphragm in respiration, and its secretion of bile passes in part temporarily into the gall-bladder, where it is stored until needed, but eventually is discharged through the common bile- duct into the duodenum, near the outlet of the excre- tory duct of the pancreas. The latter organ, lying transversely across the abdomen, below and behind the stomach, secretes* a juice most important in the chemistry of digestion. In some respects it resembles the saliva in that it converts starch into maltose; but it is far more complex, and possesses a second ferment that digests albumin, and a third that emulsifies fats. The pancreatic juice, the bile, and the secretion of the glands of the intestine are alike alkaline in re- action. The bile may be regarded as an adjuvant in intestinal digestion, although it also contains waste matter cast off by the liver from the blood. Digestion in the Intestine. — Of the secretions of the small intestine, that coming from the duodenum is the most important in its chemic action on food. The stomach-contents entering the intestine in the form of chyme are sharply acid in reaction, owing to free hydrochloric acid, and are semifluid or fluid in consistency. Chyme does not pass rapidly down the in- testine, but its course is delayed through the interven- 1 6 THE DIGESTIVE APPARATUS. tion of the vaivulse conniventes and villi. It is soon rendered alkaline by the action of the intestinal secre- tion, the bile, and the pancreatic juice. These vari- ous secretions at once take up the role of digestion, the albumin being still further converted into pep- tone, and the starches into maltose, and cane-sugar into glucose, while the fats are emulsified. Absorp- tion may begin through the activity of the veins and lacteals with which every villus, as well as other parts of the mucosa, is provided. When prepared, the available nutriments are absorbed from the intes- tinal contents through a process of selection, while certain harmful matters are discharged through the excretion of the glands. It is thus seen that there is a more or less continuous interchange of fluids be- tween the intestine and the blood-vessels. The veins from the intestine discharge themselves through the branches of the portal veins into the liver ; the lym- phatics, carrying much of the fat, empty themselves into the thoracic duct, and ultimately into the great central vein, or the vena cava. The blood from the stomach and intestines, freighted with aliment, passes to the liver, where the various substances are further modified and refined before their final reception into the systemic veins of the body. The Large Intestine. — The small intestine is guarded by the ileocecal valve where it communi- cates with the large intestine. The latter is about four to six feet long in the adult, and is divided into three portions: the cecum, a short and relatively wide pouch, which has the vermiform appendix and communicates with the colon, the principal part of the large intestine. The colon has an ascending, a HYGIENE OF THE TEETH. 17 transverse, and a descending portion. The last- named, located on the left side of the abdomen, bends to form the sigmoid flexure, and finally reaches the rectum, which terminates in the anus. It is the office of the large intestine to retain the waste matter and overflow from the small intestine, and to hold the feces until its liquid portions are sufficiently absorbed. The sigmoid flexure acts as a valve and prevents the descent of the feces into the rectum until the act of defecation occurs. The feces should then be of proper consistency, and through contraction of the colon are discharged from the descending portion into the rectum, and with the assistance of the abdominal muscles and those of the rectum complete the process of evacuation. HYGIENE OF THE TEETH. Deformities. — As the result of inherited peculi- arities the teeth are sometimes too large in proportion to the length of the jaws, and, as a result, they are forced out of line, and are crowded against each other, so that it is difficult to give them proper care. Such de- fects occasionally result from the too frequent habit of moutii-breatiiing, a practice that commonly follows ob- struction to the nasal pas- sages through hypertrophy of the adenoid tissue in the vault of the pharynx (see page 98.) The deformity referred to consists in narrowing of the hard palate and the maxillary Fig. 2.— Deformity of the teeth caused by mouth-breathing. i8 THE DIGESTIVE APPARATUS. arch, so that the line of the incisor teeth above project some distance beyond the line of the lower incisors, as illustrated in Fig. 2. The lower Fig, 3. — Asymmetry of the face due to a receding lower jaw, the result o< mouth-breathing. jaw is apt to recede, and the symmetry of the face is thereby disturbed as shown in Fig. 3. Fig. 4 shows the same face in which the lower jaw is Fig. 4. — Lower jaw brought forward into its proper position. brought forward in its proper position. A deformity somewhat resembling this results from the habit of *' thumb-sucking." In this condition the upper in- HYGIENE OF THE TEETH 19 cisors are directed outward and the lower incisors somewhat inward, as ilhistrated by Fig. 5. The habit of breathing through the mouth is commonly associated with that of "thumb-sucking." From Fig. 5. — Deformity caused by thumb-sucking (Darby). whatever cause arising, habitual breathing through the mouth leads to the accumulation of organic mat- ter about the teeth and thus favors the destruction of dentin. Certain families through several genera- tions have soft or feeble teeth, apparently because of some congenital disturbance in the nutrition of the parts. It is commonly believed that in such individ- uals much more care is required to prevent the devel- opment of caries. These poorly developed teeth are sometimes seen in scorbutic or rachitic children, and Fig. 6. — Teeth in congenital syphilis. in those suffering from congenital syphilis; but the con- dition is also present in those who in other respects ap- pear to enjoy good health. In congenital syphilis the secondary teeth are affected in a characteristic way 20 THE DIGESTIVE APPARATUS. (Fig. 6). The incisors are peg-shaped, notched, and sometimes placed at such an angle that their cutting edges are found to meet. Many cases of irregular eruption of the teeth are improperly attributed \o syphilis, and the same may be said of the notching that occurs along the teeth of many fairly healthy children — irregularities not identical with the peculi- arities pointed out by Jonathan Hutchinson. Causes of Decay. — It is commonly believed that in the matter of resistance and external irritation the teeth of certain individuals are naturally faulty. Even when the teeth receive reasonably intelligent care the development of caries is a constant source of anxiety; on the other hand, in certain families, and particularly in certain races, the teeth are naturally strong and are often retained until old age — even when they receive no further care than that which, comes from vigorous use in the mastication of coarse and resisting foods. A like difference may be noted in the integument of people, and may be explained by assuming that this depends upon some peculiarity in nutrition. The form of diet has been thought by some to be a factor in caries of the teeth. It has been noticed that the teeth that are least called upon for mastication are often the most delicate. Strong and resisting teeth seem to come naturally to those who live upon coarse foods. Apparently the innerva- tion and blood-supply is better in healthy individuals who use their teeth somewhat severely. While common observation teaches that the devel- opment of caries depends in part upon the suscepti- bility of the teeth of certain individuals, this fact has been denied, and apparently with some reason. CAUSES OF DECAY OF THE TEETH. HI Black, of Indiana, subjected a large number of ex- tracted teeth to a great variety of tests, including their exposure for varying periods to the action of chemicals and to the attacks of bacteria. When these teeth were subsequently examined by the most careful methods, there was seen to be practically no difference in the resistance that they had shown. Strong and feeble teeth were affected alike, and it may be inferred that poor teeth do not differ materially from those that are usually regarded as strong in their resistance to the influences that produce decay. The old opinion that the teeth are injuriously affected through the action of certain acids found in the stomach is also disappearing. Miller, who found more than one hundred varieties of micro-organisms that grew in the mouth or about the teeth, believes that caries is the result of lactic acid produced by the growth of certain of these bacteria. It is now generally accepted that the bacteria are in some way responsible for dental caries; but there is a growing doubt as to lactic or other acids playing any special part in this process. Hopkins, of Harvard, has taken up the question, and has shown that in these micro- organisms, of which he has found about fifty varieties commonly present in diseased teeth, about one-fifth of the number were producers of lactic acid, but the strongest proportion of acid that he was able to pro- duce by the growth of these bacteria was 0.5 per cent. He subsequently found that if teeth, good and poor alike, were subjected to a solution of lactic acid in the strength of 0.5 per cent, for a period of four months, no carious action whatever could be dis- covered. The observer emphasizes a fact, previously 22 THE DIGESTIVE APPARATUS. known, that some of the organisms that are appar- ently destructive give rise to secretions alkaline rather than acid in reaction. It has been commonly observed that some mouths in which caries is conspicuous show a free secretion of saliva and a constant alkaline reaction. Much has yet to be learned about the mat- ter; but it may be assumed that to bacteria we must attribute dental decay; that the question of natural resistance of the teeth plays but a subordinate part; and that the character of the diet, so long as it is suf- ficiently nutritious, has not been shown to have any influence whatever. When fragments of food, to- gether with the secretions of the mouth, find lodge- ment between and around the teeth there is afforded an opportunity for the growth and development of bacteria. Some idea of the number of these organ- isms may be inferred from what has been said. It is believed that micro-organisms are concerned in the formation of the discolored tartar so disfimirine to the teeth and injurious to the gums. But teeth are at- tacked and cavities are formed without the develop- ment of tartar; all that seems necessary is for the or- ganism to find a lodgement in some protected place where they are removed from the action of the tooth- brush and other toilet articles commonly used to dis- lodge them. Catarrhal irritation about the margin of the gums leads to their recession and exposure of the teeth where they are unprotected by enamel. This catarrhal condition is due in large part to the action of bacteria, but the condition is much favored by the continual irritation from tobacco and acrid foods, also by the presence of tartar and by carelessness in the use of tooth-brushes, tooth-picks, and the like. CAUSES OF DECAY OF THE TEETH. 23 A disease of much importance that occasionally af- fects the gums is known as pyorrhoea alveolaris, commonly called Riggs' disease. This was at one time believed to depend upon a constitutional condi- tion, and in some way to be associated with the so- called uric-acid diathesis. This view^ never seemed logical, and is overthrown by recent study. Un- doubtedly, as in the case of other infections, perfect systemic health is the best safeguard against infec- tion, but that good general health can prevent the development of bacteria is untenable. Younger, of Chicago, regards the disease as essentially of bacterial nature, and views injury to the gums, and especially the perforation of the peridental membrane, as the first step in its process. Such injuries are usually produced by the forcible introduction between the gum and tooth of hard foreign bodies, like seeds of berries, bits of bone, and bristles from the tooth-brush. Recent observation has shown that infection accompanying pyorrhea and infection occurring at the extremity of the roots of a tooth, or within the tooth itself, often has a deleterious effect upon the general health. A general infection and the source of grave organic disease, such as arthritis, nephritis, or endo- carditis, as well as obscure and destructive diseases of the special organs, especially the eye, are known to have origin in this way. Often only an x-xdcy examination will reveal the abscess. Devitalized teeth, often made necessary in the filling of those teeth in which neglected caries has taken place, are prone to deep infection at the tip of the roots. It will be seen that it is most advisable to keep the teeth in such a healthy condition that the killing of 24 THE DIGESTIVE APPARATUS. nerves and filling of roots may not be necessary. Also it will be seen that when there is evidence of resorption of bone around the roots of the teeth in which infection may be harbored, it is desirable to have such teeth removed. Such sacrifice would be unnecessary if sufficient attention were given to the prevention of caries and pyorrhea. Preservation of Teeth. — From what has been said it may be concluded that, so far as we understand the matter, the preservation of the teeth resolves itself into a few simple principles; namely, the prevention of overcrowding, the avoidance of chemical or me- chanical injury to the teeth and gums, the careful and frequent cleansing of all the exposed surfaces of the teeth, and the use of such harmless antiseptics as will prevent the long continuance of pathogenic bacteria in the mouth. Periodic visits to the dentist are most important, both to prevent decay and to detect and treat any pus-collections or abscesses. The most easily available means of protection lies in the proper cleansing of the teeth. For this pur- pose the frequent use of the tooth-brush is indis- pensable. The ordinary bristle brush has been op- posed on the ground that it is too hard and is liable to injure the gums, particularly when stray bristles are thrust into the soft parts around the teeth. Brushes of badger's hair, of felt, and of various other substitutes, have been recommended. Most of these contrivances, however, are lacking in the essential resistance and elasticity so important in the thorough dislodgement of foreign matter. The bristle brush in which the bristles are not too closely placed together, thus admitting of their passage between the teeth, is PRESERVATION OF TEETH. 2$ the most practical instrument. Great care should be taken not to allow the bristles to spread, and the ' brush should be discarded before it is soft or ragged from long use. The brush should not be too broad, and the handle should be bent in the direction of the tuft on the brush so as to admit more easily the reaching of the various curved surfaces of the teeth. The brushing should be practised after each meal and before going to bed, and once daily should be ac- companied by the use of a tooth-powder sufficiently coarse to produce some grinding and polishing effect. A powder that is too soft or too fine is of little avail. Powdered chalk and orris root are common bases for tooth-powder. Some harmless antiseptic, such as borax, oil of wintergreen, or tincture of myrrh, should be incorporated with the powder to help destroy any colonies of bacteria that may be reached. Twice each week all the exposed surfaces of the teeth should be carefully gone over, and, with the assistance of the tooth-powder, carefully rubbed with a narrow chisel- like piece of a wood that is hard and fine-grained in texture, such as orange-wood, so as to smooth away all the roughness and inequalities. This puts a smooth polish on the teeth and renders their subse- quent cleansing by means of the tooth-brush a com- paratively simple matter. If this rule were applied in the care of children's teeth the work of the dentists would be greatly restricted. Of equal importance is the daily use of soft silk twine, known as dental floss or, better, dental tape. It should be drawn between the teeth firmly but carefully, so as to remove foreign matter that cannot be reached in other ways. Also by passing the tape around the teeth, drawing it back 26 THE DIGESTIVE APPARATUS. and forth, the teeth may be polished, accumulations removed, and caries prevented. It is important not to cut or irritate the gums nor to loosen their attachments to the teeth. A little experience enables one to ac- complish the work deftly and quickly. In the neglect of this practice the teeth can hardly be said to have been cleaned. In addition to these methods, the mouth and teeth should be carefully rinsed every night with some innocuous antiseptic solution. Some of the most harmless antiseptics are powerful germi- cides, and should be employed to the exclusion of others that may do injury to the general health of the individual as well as to the teeth. Tincture of orris, rose-water, and alcohol in equal parts, flavored with a drop of oil of bitter almond, make a very agreeable mouth-wash, and it may be rendered more actively antiseptic by the addition of 0.5 per cent, of formalin. The importance of the teeth in digestion is not sufficiently recognized. Many cases of chronic indi- gestion arise from imperfect mastication due to faulty dentition. In all such cases it is of primary impor- tance to have decayed teeth filled, or if there are many missing teeth they should be replaced by artificial ones. Otherwise medication and dietary regulation may be of little avail. HYGIENE OF THE QASTR0=1NTESTINAL TRACT. The Appetite. — When there is bodily inactivity or mental indolence, as compared with habitual physical or mental exertion, the problems of nutrition must differ widely. The long struggle of the human race to find at all seasons sufficient nourishment to satisfy HYGIENE OF THE GASTRO- INTESTINAL TRACT. 2/ the demands of life doubtless led to the building up of physiologic laws which made it possible for the or- ganism to undergo periods of starvation, to be fol- lowed by periods of repletion. This history of feast and famine must have left to its survivors an appe- tite that urged its possessor to feats requiring the greatest energy of body and mind ; conversely great activity and great expenditure of energy should lead normally to an appetite correspondingly large. In reviewing the history of organized life, it will be found that appetite has been the great ruling principle that has enabled the living cell to cope successfully with the destructive agents that surrounded it. A good appetite still reminds one of the most necessary factors in our survival, and we instinctively feel that its disappearance or its unnatural perversion is a seri- ous warning of degeneracy or decay. This splendid instinct so necessary for our existence has now more than ever to meet with sudden modifications resulting from the complexity of modern life. While pri- marily responsible for the discovery of innumerable aliments, the very abundance in this generation, both in quantity and variety, is embarrassing, and we find the results of unnecessary and artificial stimulation in the unnatural desires for food. The lack of at- tention as to the appropriateness of food subjects not only the digestive apparatus, but all the cells of the individual organism to distress and not infrequently to disease. In this matter the problem to be solved is, first, how to train the appetite into natural and wholesome paths; and, second, how to live so that by means of proper physical, mental, and moral activity there may be successfully oxidized the kind and 28 THE DIGESTIVE APPARATUS. quantity of nutriment required in normal life, and successfully discharged the waste products that re- sult from the oxidation. It is unsafe to trust the individual to the guidance of the appetite alone, for the reason that this instinct was built up for a condition of existence very different from that which enables the people of this country to indulge them- selves to-day. Nevertheless, the appetite is a more reliable guide than speculation, and more trustworthy than a certain narrow scientific view which would select foods along the lines of nutritive values ascer- tained by chemical experiments. Not that there should be neglect of knowledge as to the calories of energy that may be developed by one substance as compared with another, or the omission of some things that may be learned by rational deduction; but it should never be forgotten that in instinct there is a guide that has been accumulating experience for un- known ages, and that if life in other respects is normal this appetite is likely to lead very nearly in the right direction. In those beyond middle age, when activity is often diminished and when the processes of metab- olism have suffered a decline, protein food, especi- ally animal protein, should be proportionately restricted. The Effect of the Mind on Nutrition. — These gen- eralities include many specific facts that will bear amplification. In the consideration of the effect of the mental and moral state upon the problems of nutrition there is much food for thought. It is no idle phrase to say that a contented mind, a willing THE EFFECT OF E YE-STRAIN ON NUTRITION. 29 disposition, and a joyous nature give rise to good digestion. It is a truth of such importance that no physician can wholly succeed in relieving derange- ments of digestion unless he takes this matter into consideration ; in other words, remorse, worry, over- responsibility, petulance, envy, jealousy, and other undesirable mental states give rise to such disturb- ances, both in primary nutrition and cellular met- abolism, that good health is not to be obtained. This explains the fact that a change of scene, a long vaca* tion, and new associations will sometimes improve the digestion and restore health generally when care- ful dieting and other measures have failed to bring relief. Unenviable mental characteristics may be- come prominent partly as the result of brain irritation that arises in many unsuspected ways. Such dis- turbance of the nervous system deranges the appetite, the digestion, and nutrition in general, as well as the mentality. The Effect of Eye-strain on Nutrition. — One of the most important of these sources of irritation is the continual use of the eyes in all manner of fine work, often in imperfect or wrongly directed light. In the modern system of education, in which children from the kindergarten upward are required to use the eyes closely upon small objects, in association with the concentration of the mind, this evil is found in an ag- gravated form. As this sacrifice of the ocular ap- paratus seems demanded by the requirements of edu- cation and culture, the nervous system has to undergo the strain as best it may. It has long been recog- nized that there result headache and various expres- sions of nervousness, but that the appetite and 30 THE DIGESTIVE APPARATUS. digestion are also made to suffer are facts that are too little recognized. Whoever carefully looks into this matter will find really that nutrition first shows the result of nerve-strain, no matter from what source arising ; and, as a rule, some peculiarity of the primary digestion gives the earliest intimation of the trouble. For instance, there may develop a distaste for certain substances in the dietary ; the appetite may become capricious or perverted. Again, a dis- turbance in motion will arise, and the stomach ma}^ contract in a spasmodic, tremulous, or irregular way, while the individual is conscious of disagreeable and sometimes alarming sensations, accompanied with eructations of gas or fluid from the stomach. Or the gastric juice may be secreted irregularly, and in many instances a long chain of dyspeptic symptoms appear without any real disease of the stomach, but merely a disturbance of the nervous system occasioned by improper habits of life. In a certain sense the stom- ach is acting in the role of monitor ; but if we are sufficiently wise it may often be regarded as that of the kind mentor. This most common experience may be avoided sometimes by removing the strain to the nervous system, and again by strengthening it by exercise, bathing, recreation, and more hours for sleep and repose. Eye-strain may be lessened or ob- viated by the wearing of spectacles that are made ac- curately and adjusted precisely; or by attending to the direction in which light enters the room, or perhaps by prohibiting the use of books printed with small or illegible type. Observance of these precautions may render it unnecessary for the individual to give special attention to his diet ; but it is the usual cus- REGULATION OF MEALS. 3 1 torn at first for the stomach to be considered the source of trouble. As the disagreeable digestive ex- periences are attributed to the stomach, the fault is commonly supposed to lie in the character of the food, and wiseacres take the responsibility of advis- ing the withdrawal of sugar, fats, or meats, and the abundant taking of oatmeal, grits, and beef- tea, a dietary most likely to undermine resisting power and in the end do infinite harm. For similar relief re- sort is sometimes had to a milk diet or to abstinence from food, because it is found that the stomach is more comfortable when it has little to do. But this erroneous course will ultimately fail ; it is wiser, when possible, to remove the cause of the difficulty. When it is impracticable to remove the source of worry it becomes necessary to modify the diet, and it is a compromise of this sort that unfortunately we must sometimes make. Regulation of Meals. — When required to adapt the diet to a tired nervous system and an irritable stomach it must be so managed that the most hearty meal should be taken at a time when it is possible for the individual to enjoy the greatest physical and mental composure, and there should not be demanded too much of the digestive organs when it is known that unusual taxation of the nervous system has been experienced. It is not generally wise in such cases to take a hearty breakfast before functional activity is sufficiently aroused ; nor is it well to allow the chief meal at midday, when the energy is likely to be taxed by work or study. It is better to wait until late in the afternoon, when, after a little rest, the chief meal should be taken — and taken slowly, com- 32 THE DIGESTIVE APPARATUS. posedly, and cheerfully. Following this there should be spent a few hours in quiet enjoyment before going to bed. This rule will seem like an absurdity to many who insist that the late dinner is in itself the sure forerunner of a bad night. This is usually true only when the midday meal has been too hearty. A delicate digestion may be overtaxed by requiring the stomach to muster all its forces too frequently in a given time. It is better economy to accept from the organism a moderate display of energy in the morning, and very slight at midday ; but at evening, when the tissues demand food and when the physiologic appetite has appeared, it may be expected that the di- gestion will perform its greatest work unincumbered by worries — muscular and mental activities that are likely to draw the blood away from the organs of di- gestion and to dissipate vital energy in too many ways at one time. If this principle is true, there is no reason why it may not apply to children as well as to adults. Of course, this need not be construed too literally in cases of sturdy and hungry little folks, who are always ready to eat. The application of the rule should be in proportion to the delicacy of the child ; but it must be remembered that the food for the child should be that which is quickly disposed of, and therefore a greater frequency of meals is usually permissible. In fact, it is not safe to use an invari- able law as to the frequency of meals in persons of any age, but regularity should be insisted upon. Con- vention is too often the arbiter in the matter, and the hours for eating are appointed without reasonable regard to physiologic requirements. Nevertheless, REGULATION OF THE DIET. 33 the rule given above may be taken as an illustration that is applicable to the majority of mankind. It does not mean that the average man has a weak digestion, but it means that he is overtaxed in a general way, and that if he does not devote some thought to the char- acter of his meals and to the hour for his repasts, then he is likely to develop, first, consciousness of the act of digestion, and, later, distress during the process. Regulation of the Diet. — It is frequently asked what should be the character of the food taken. The answer must at first be as general as the question ; and it may be said that the digestion may be taxed either in the quantity or the quality of food, and in direct ratio with the resisting power and vital energy of the individual. The climate and occupation must also be considered. A stalwart wood-chopper requires in the winter large meals rich in fats and carbohy- drates, which, in the process of oxidation, produce relatively a large amount of heat, and albumins that more directly nourish the muscles and nerves. With such a worker, so long as there is sufiicient nutritive value in the food, great attention need not be paid to its variety, nor even to its digestibility. For instance, certain woodsmen crave a very resisting form of pastry because it "stays by" and does not too quickly leave the stomach empty. For such per- sons the hastily prepared oatmeal-porridge is suit- able, because it is slow to digest. For the sedentary and indolent person the supply of food should be small and digestible. For the sed- entary brain-worker the amount taken should be increased in proportion to his mental activity, and it should be easily digestible and very nutritious. In a 3 34 THE DIGESTIVE APPARATUS. cold climate, as is generally known, large amounts of fats are required, while in hot climates the carbo- hydrates and fruits seem to be demanded by the or- ganism. For the ordinary business or professional man, or the student, a breakfast may be advised to con- sist of one or two soft-boiled eggs or an omelet, a piece of bacon or fish, a roll or some toast, and one cup of coffee. Oatmeal-pudding is unsuitable, be- cause it is rarely well mixed with saliva, but is hur- riedly bolted, deglutition being facilitated by the covering of cream. The same may be said of other "cereals," except those that are partially dextrinized by previous cooking in the process of manufacture. Early in the morning at least a glassful of pure water, neither iced nor hot, should be taken. If the breakfast hour is at eight, the luncheon hour should be at one. Milk is an excellent aliment for this meal. It disagrees with some, but this is usually be- cause other foods are taken with it. Milk is not to be regarded as a drink, but as a food. It is best taken alone, but it generally agrees better if a certain amount of starchy food is taken at the same time, although the latter should be carefully masticated and insalivated, and should neither be saturated with milk nor washed down by it. Milk should be drank and bread eaten slowly. The object of this is to take advantage of the action of the saliva in converting starch into maltose. For those who dislike milk, or with whom it does not agree, the luncheon may consist of broth or light soup, bread and butter, a few oysters, sweet- bread or a light salad, and perhaps a little fari- naceous pudding like corn- starch, thoroughly pre- REGULATION OF THE DIET. 35 pared rice, or tapioca. Of such a luncheon fruit may form a part, or fruit may be taken before breakfast, and rarely after dinner. With such an arrangement, dinner should be taken at six or thereabouts. This meal should be as much as possible served slowly in courses. The conventional arrangement of the courses at dinner is a desirable one, and is appar- ently the result of the experience of ages. The pre- liminary course of a good soup that is not too rich, to be followed by fish, then a joint or roast, with one or two vegetables, a small salad, bread, and some simple dessert constitute a. typical dinner, and in amount should be sufficient to make up for the some- what scanty meals that preceded it. The digestion is usually taxed in proportion to the variety of the foods taken ; therefore, when the stomach reacts unfavorably to an extended meal, food should be limited — first in variety, and second in quantity. The precise amount to be taken during all these meals is a matter that must depend upon individual require- ments. As a rule, more food is taken than neces- sary; but there is a large class of nervous people who eat regularly, but rarely take a sufficient amount of really nourishing foods to replace that which is lost by waste. The following table is given by Parkes as showing the amount of food required by a healthy adult in 24 hours (see page 404) : In laborious occupation. At rest. Nitrogenous substances — e. g. flesh . . 6.0 to 7.0 oz. av. 2.5 oz. av. Fats 3.5 " 4.5 " i.o " Carbohydrates 16.0 " 18.0 " 12.0 " Salts _r2 " 1.5 " 0.5 " 26.7 to 31.0 oz. av. 16.0 oz. av. 36 THE DIGESTIVE APPARATUS. To this should be added from fifty to eighty ounces of fluid. lu the arrangement of meals above described the requirements of the average brain-worker have been in mind. In some cases a heartier breakfast will be demanded, and with others a certain amount of lassi- tude and depression may occur late in the afternoon when only a light luncheon has been taken. If the latter complaint is made, relief may be had by allow- ing a cup of tea and a cracker to be taken at four o'clock. Drank at this time, tea rarely disturbs sleep, and it is not likely to blunt the appetite for dinner. Some individuals have naturally a rapid digestion, and a sense of hunger is experienced toward bedtime. In such an event it is best that a little simple food be taken. Only those who have vigorous constitutions can indulge at night in "lobster a la Newburgh," rarebit, and the various other savory and rich prepara- tions that the use of the chafing-dish has made popu- lar. This is not an argument against eating before going to bed, but merely an instance of the impru- dence of taking food unsuited to the individual or to the occasion. It must not be supposed that the dietary cannot be varied, for there is no doubt that monotony in daily living is bad hygiene. Proper Cooking. — Many articles of diet that are considered unwholesome are usually so merely because they are badly prepared. Hardly too much can be said in favor of scientific cooking, and that most important article of diet, bread, is most often open to criticism. Really well-baked, sweet, crisp, " nutty " bread is regularly found only in exceptional households. Indeed, many people do not seem to COFFEE, TEA, AND COCOA. 37 know what ' ' good bread ' ' means. Much of the tirade against potatoes is unjust, and results from igno- rance in their preparation or the prejudice of certain writers. A great variety of green vegetables that are not only palatable but fairly nutritious, and some of the constituents of which are necessary because they contain acids, salts, and extractive matters required by the economy, are easily enough digested when they are well prepared. Aside from their nutritive value, they are useful in making more bulky the contents of the alimentary canal, thus favoring the action of the stomach and intestines, whereby constipation is avoided and a healthy state of the intestinal mucous •membrane is favored. Fruits. — It is rarely necessary to urge Americans to eat fruit; they too often err in taking too much. It is not uncommon in this country for people to eat fruit at any time during the day or evening. The benefits from eating fruits are undoubted; they act upon the digestive organs somewhat like the green vegetables, but they have other advantages from the acids contained, and also because they appeal to the esthetic sense. The eating of fruit before breakfast is unobjectionable in most instances. Fruit may also properly form a part of the luncheon and dessert, but it should not be eaten between meals. The harm in eating fruit may lie in its excessive use, or in eating that which is unsound or unripe. Coffee, tea, and cocoa have their place in normal diet; and while they occasionally are the source of much disturbance, it is generally true because of over- indulgence in them. As a rule, coffee and tea are taken in excess, and, on the whole, do more harm 38 THE DIGESTIVE APPARATUS. than good. The plea is made for the temperate use of these substances that have come to be almost necessities of the human race. After the morning bath a small cup of coffee, gently stimulating the circulation and the motor function of the alimentary tract, and apparently making more available the energy accumulated during the night's rest, generally accomplishes good. The use of tea in the afternoon has been pointed out. Both coffee and tea, particu- larly the latter, antagonize the action of the saliva upon starch, and, therefore, taken in excess may retard digestion. There will ensue little trouble if bread is sufficiently well masticated and if no drink be taken while eating. The saliva passing with the food into the stomach stimulates the secretion of that organ, and therefore indirectly assists in the digestion of the albumins. This is another reason why careful habits in eating should be inculcated early in life. Sugar contains much stored-up energy, and is a useful article of diet; but if taken early in the meal, it lessens the appetite and embarrasses digestion. The action of condiments is quite varied. Most of them appeal to the sense of taste, and act as local salivary and gastric stimulants. The high seasoning of food not only depresses the sense of taste for simpler foods, but also exercises a harmful influence in irri- tating the gastric and intestinal mucous membranes and the liver. Fats and oils should be included in every rational dietary. Even in warm climates these substances have always formed an important item in the foods that are selected by choice. It is difficult to explain the fact that they are disliked by some children, FATS AND OILS. 39 although the health may be failing for the want of them. In such cases evident improvement is ob- served when fats are prescribed by the physician. Fats should not be taken before or early in the meal, for the reason that they are supposed to protect the mucous membrane of the stomach from its normal stimulation by the other foods, and thus tend to lessen the secretion and motion of that organ. If fats are taken late in the meal or following it, they do not dis- turb digestion unless fermentation occurs. While in the stomach the delicate envelopes of the fat-cells are broken, when they pass with the chyme into the in- testine and are absorbed by the lacteals in the villi. Intestinal digestion of fats seems to be merely that of the splitting up of the fat-cells, a process of emulsifi- cation that is for the most part accomplished by the action of the pancreatic juice, assisted by the secre- tions of the liver and duodenum. Quantities of minute particles of fat thus subdivided are to be found in the lacteals during intestinal digestion, and they subse- quently appear in the blood, from which the tissue- cells readily appropriate them. It will thus be seen that the assimilation of fats is a simpler process than that attending the albuminoids, starches, and sugars; and to suppose that fats are unwholesome is an erro- neous conclusion, probably based upon the fact that when incorporated with starches and sugar in the form of pastries, etc., they are likely to disturb digestion. This is true for the reason that the starch-cells are pro- tected by the fats from the action of the saliva in the mouth and stomach and from the action of the pan- creatic juice in the intestine; and for the further reason that the fats are often superheated in cook- 40 THE DIGESTIVE APPARATUS. ing, thus giving rise to indigestible and irritating fatty acids. The salts compose an important part of the diet, and occur as various combinations of sodium, potas- sium, lime, magnesium, and ammonium. Of these, the most important is sodium chlorid, or common salt, which makes up 5.5 + parts in every 1000 parts of the plasma of the blood, and occurs everywhere in the body except in the enamel. A sufficient amount is not derived from unseasoned foods, and therefore the use of salt as a condiment is universal. Some of its derivatives, of which hydrochloric acid is the chief, form a most important constituent of the gastric juice; and it seems reasonable that salt should be taken in connection with the albuminoids, with which the gas- tric juice has most to do in the process of digestion. Salt may be taken in excess when salted meats form the chief aliment or when an unnatural habit of eat- ing salt is acquired. But if one is deprived of salt there is not only a disturbance in the cellular nutri- tion, but also a depreciation in the gastric juice. Drinking Water. — The question of drinking water is one that requires some consideration. As has been stated, about eighty ounces of fluid should be taken daily. This includes that which is taken in combi- nation with solid foods. Most people leading sedentary lives take too little water, and also err in taking it for the most part when eating. A certain amount of water always should form a part of every meal, and particularly is it necessary' in those who have very ac- tive digestion. It assists the escape from the stomach of those substances made soluble by the action of the gastric juice and the churning effect of the stomach, ALCOHOLIC BEVERAGES, 4I and will sometimes make digestion comfortable when it otherwise would be attended with distress. But while it is allowable for water to be taken with meals, it again should be repeated that the food should not be washed down. Such a practice not only interferes with starch digestion, but it also enables the individual to swallow morsels of food altogether too large and re- sisting for the stomach to manage comfortably. The proper time for taking the bulk of the fluid is between meals, particularly early in the morning and late at night. It is a fact well known to physicians that women especially drink too. little water; the habit probably results from the inconvenience attending the taking of the proper amount. While a person may be saved some embarrassment by this kind of denial, positive harm usually results from the continuance of the practice. The American habit of drinking ice- water has been much censured. It is unnatural, and in some instances harm may be traced directly to it. In many no injurious effect appears to follow its use. This must be said in its favor, that those who enjoy cold drinks are likely to take sufficient water, which is not true of the ordinary individual. Harm comes from the practice of drinking hot water in the false belief that it prevents or cures dyspepsia. Doubtless hot water has its place, and it is to be recommended rather as a remedy than as a daily usage. Alcoholic Beverages. — In general it may be said that alcohol is unnecessary; and, aside from the vi- cious results of inebriety, it sometimes is capable of producing disturbances of digestion. This is particu- larly true in those unaccustomed to its use, and is truer gf beer and wines than of the distilled liquors, except 42 THE DIGESTIVE APPARATUS. when they are used too freely. With the continued use of alcohol in any form it is possible so to disturb the nervous system that nausea, loss of appetite, and other functional disturbances arise; and if the practice is still further continued congestion and catarrh of the stomach and irritation of the liver may be expected. These facts are, of course, universally accepted; but the question is how much may digestion be harmed from the taking of a small amount of wine or spirit as a part of an occasional feast or as a regular accompa- niment of dinner . While it is a fact that wines and beers rich in extractive matters interfere with gas- tric digestion, it must be admitted that unpleasant effects are not usually experienced in temperate people, particularly when they are active in mind and body. Certain individuals are always the worse from even the temperate use of alcohol, tobacco, tea, or coffee; and such individuals should also abandon chocolate and cocoa. These persons are exceptional, however, and in the case of the ordinary man, lead- ing an active life, a moderate amount of alcohol may be taken without harm. Unfortunately, moderation is not always satisfactory, and deplorable results may arise that are apparently traceable to the grad- ually increasing use of alcohol. Other Stimulants. — It is held by certain authors that stimulants of all kinds should be avoided, which would put the ban of exclusion upon condiments, spices, hot foods, ice, and carbonated drinks, as well as upon tea, coffee, cocoa, and alcohol. But this posi- tion is not logical, for it can be shown that the diges- tive apparatus is stimulated on the one hand and de- pressed on the other by equally potent factors that cannot be excluded ; for instance, by constantly occur- EATING AFTER E ATM INC. 43 ring emotional states as well as by recreation, exertion, and fatigue. The latter group will be considered as merely physiologic influences, and therefore not open to criticism; but this conclusion is not altogether true. Certain mental states result in interference with digestion to such an extent that the appetite may be lost, nausea induced, the gastric secretion interrupted, and the movements of the stomach and intestine depressed, or irregular and spasmodic movements induced which lead to the upward dis- charge of gas from the stomach and perhaps regurgi- tation or vomiting of the undigested food; or there may be developed such severe contraction of the gas- tric muscles that pain is induced. The same causes very frequently induce gastric distress and occasional neuralgia. On the other hand, in tempting displays, agreeable zests, and appetizing odors, we have in- stances of stimulants that as often lead to excess in eating as they do to increased activity in digestion. A curious phenomenon is the overdistention of the stomach and intestine with gas which apparently does not arise from fermentation, but appears to be abnor- mally secreted in the stomach and bowels. Under such conditions a gentle stimulant will enable the diges- tive organs to regain their equilibrium, after which a small amount of fluid food might be easily managed. These are the cases for a cup of tea or coffee, or a pos- set of aromatic herbs, and those who have no moral scruples against its use may be quickly relieved by a thimbleful of brandy. Eating after Bathing. — A similar state of depres- sion of the digestive organs may result from a too pro- longed bath ; and the popular opinion that it is un- safe to eat after bathing is based upon the fact that 44 THE DIGESTIVE APPARATUS. functional energy is for the time being apparently diminished, and in some people digestion is thereby interrupted. This fact does not apply to all alike, but it is true with sufficient frequency to give rise to the popular belief. Eating after Exercise. — Physical exertion is more likely to disturb digestion than bathing. Its effect upon the digestion is similar to that produced by mental fatigue. Singularly enough, this fact has not been universally recognized ; and it is common for people who are physically exhausted from tennis- playing, bicycling, and other violent exercises to in- dulge themselves in a hearty repast without having previously rested. Most people understand that it is unsafe to undergo vigorous exercise directly after a meal ; but they do not realize the mistake of eating heartily when too tired. These truths apply more to those who are untrained and unaccustomed to physical strain ; but athletes have discovered that it is not wise to eat heartily when about to engage in great exertion. Flint found that during a period in which the pedestrian Weston walked a total of 317 miles in 5 days, he consumed on an average about 83 grammes of proteids daily. Yet in the diet of an ordinary farmer or mechanic in this country about 100 grammes of proteids are taken during 24 hours. Of course, other forms of food besides proteids are taken, and much energy is derived from the combus- tion of the fats and carbohydrates. As a rule, a well-trained man who is carrying on for a prolonged period unusual physical effort is able to eat and di- gest more food than the ordinary man. The dispro- portion between the nutriment taken and the energy expended may be approximately ascertained by noting CARRIAGE AND DRESS INFLUENCING DIGESTION. 45 the change in the weight of the body. A. P. Bryant states that Sandow's daily diet contains 244 grammes of proteids, which supplied 4460 calories of energy. Under great strain more proteid is required than under conditions of normal exercises ; but when the strain is to be short and severe it is wise to re- trench at the table lest there should succeed re- bellion in the stomach. Influence of Carriage and Dress on Diges- tion. — Abnormal condi- tions of the liver are for the most part secondary to disorders of the stom- ach and intestines, and in cases in which there is de- rangement of the prima vise it is usually safe to conclude that the liver is also out of condition. One of the most com- mon causes of sluggish- ness in hepatic circula- tion and secretion, as well as of the disturb- ances of the intestines and other portions of the digestive apparatus, may be attributed to faulty car- riage of the body and relaxation of the abdominal muscles, lessening of the abdominal type of respira- tion, and consequently the loss of diaphragmatic mo- tion. All of th^e conditions are very much aggra- FlG. 7. — Showing constriction of the abdomen and, necessarily, the displacement of the abdominal vis- cera, produced by an improper corset. 4.6 THE DIGESTIVE APPARATUS. vated, and some of them are directly induced, by the improper dress ahnost universally adopted by women^ and to some extent by children. In illustration may be instanced a woman who is said to dress loosely. With her corset removed she is found to measure twenty-seven inches around the waist, but as ordi- narily dressed she measures twenty-one inches around the waist outside the garments (Fig. 7). For the correct performance of function on the part of the stomach, liver, and intestines it is neces- sary that free and properly related movements of these organs should take place. Such movements are impossible in the large majority of women. The defects are so common, and the deformities of the body necessarily associated with them begin so early in life, that they are largely overlooked, and are argued to be natural and beautiful by the mass of womankind. A certain amount of intra-abdominal pressure is necessary if the viscera of that region are to be held in their proper places and proper relations. This is possible only when the body is erect in sit- ting and standing, when the chest is kept habitually raised to its normal position, and when the abdom- inal muscles are strong, and are not allowed to relax, pouch out, and thus favor the descent of the organs (Fig. 8). This position should be urged during child- hood, and mothers should be instructed in the proper method of dressing their children so that the chest may have the freest motion without meeting with opposition from the clothing. All garments should be suspended from the shoulders, to prevent the down- ward displacement of the stomach, intestines, kid- neys, liver, etc. Practically all women stand in an CARRIAGE AND DRESS INFLUENCING DIGESTION. 47 improper attitude, a fact of which they are appar- ently ignorant Others would not remain ignorant of the fact but for the concealment attending women's dress. That this is no exaggeration, every physician who has given the subject careful study Fig. 8. — Showing the shape of the abdomen in a well-developed woman standing in the correct posture. Fig. 9. — Showing the shape of the abdomen and the contours of the body in a well-developed case of enteroptosis. will readily agree ; but the fact that more than 50 per cent, of all civilized women, in all classes of life, have developed the condition known as enteroptosis (Fig. 9), which means that the stomach, intestines, very often the kidneys, and sometimes the liver, are dragged downward and remain permanently out of their proper position, is not generally known. Such, 48 THE DIGESTIVE APPARATUS. however, is the case; and this condition more than any other cause is responsible for the constipation, backache, debility, biliousness, early loss of com- plexion, headache, and that long list of ailments of which so many women in all civilized coun- tries are victims. Those who have vigorous con- stitutions, strong nervous systems, and who keep the body in a healthy tone by leading out-of-door lives and avoid the common habits of worry and petu- lance, may live with moderate comfort even though suffering from the enteroptosis made necessary and permanent by the methods of dress. But the greater proportion of women lack these sturdy qualities, and therefore suffer more or less from the symptoms described. Furthermore, this downward dragging of the abdominal organs leads to displacements and derangements of the pelvic organs, and the genito-urinary diseases so common in women are a natural result. In young children the intestines have not yet assumed that position which is normal in adult life, and in some this lack of development makes a constant difficulty in evacuation of the bowels. By a slow process, and in the absence of interference, these matters in time right themselves; but not infrequently the child is so handicapped through the want of out-of-door sports, adequate physical training, and proper methods of dress that the large intestine never assumes its proper place. Constipation and Diarrhea. — Downward dis- placement of the bowels not only leads to consti- pation, but it also favors a catarrhal state of the intes- tinal lining, leads to intestinal indigestion, and occa- sionally produces diarrhea, and sometimes pain and the discharge of mucus with the feces. There are INFLUENCE OF DIET. 49 other reasons aside from displacement that com- monly give rise to constipation and other unhealthy conditions of the intestines, important among which are diet and habit. Influence of Diet. — It has been said that the cel- lulose of fruits and vegetables exercises a wholesome influence upon the intestinal mucous membrane, in- creasing the bulk of the contents and stimulating the activity of the secretions of the intestinal glands and the contraction of the intestinal muscles. Formerly, when the use of coarser foods was more common than at present, when flour and meal were less carefully bolted, constipation is said to have been less common. For these reasons it is often advised that those who suffer from constipation should confine themselves to coarse and bulky foods. It is true that such a diet is beneficial to one class of people, but it is harmful to another. When it happens that the mucous membrane of the intestine is less than nor- mally irritable, when the unstriped muscle-tissue is so quiescent that it fails to contract from the stimulus offered by soft and semifluid contents, it is found that both the secretion and motion of the part are so dimin- ished that there is slowing of the intestinal stream, and an evacuation does not occur until there is a con- siderable accumulation in the colon. Under such conditions the bowel is usually successful in empty- ing itself unassisted, but only irregularly and after improper delay. Such stagnation of the intestinal stream is injurious to the intestine and to the organ- ism. To the former, because of the undisturbed har- boring of micro-organisms, the dulling of the normal irritability of the motor and secretory nerves, and the weakening of the intestinal muscle ; to the latter, 50 THE DIGESTIVE APPARATUS. because of the absorption from the intestine of cer- tain toxic substances that are much more Hkely to be formed when the intestine is inactive. These toxic substances, finding their way, first, to the liver and then to the general circulation, develop those symp- toms that are commonly recognized under the name of biliousness. This term has come to have a broad meaning, which, indeed, is necessary, as the expres- sions of this form of auto-intoxication are varied. It will be understood how a coarse diet may be very ser- viceable in relieving the condition described above. But there is another and nearly as large a class in which the mucous membrane and muscle of the intestine are too irritable. This results sometimes from a low grade of inflammation affecting the superficial lining of the intestine, and sometimes to over-impressionability of the nerves of the part. Under such circumstances a bland, unstimulating diet results in intestinal contents that excite the irritable bowel to proper activity; but if the food is coarser and contains much ^vegetable fibers or husks of grain it causes so miich mechanical irritation that the intestine contracts spasmodically and prevents the normal onward movement of the feces. These influences may so disturb the part that over-secretion and over-motion result, and a diarrhea follows, usually to be succeeded by constipation, and it in turn by diarrhea. The physical condition ac- companying either one of these states may not be so unlike those accompanying the other ; and whatever course of living most tends to regularity is equally useful in the prevention of diarrhea and constipation. It so happens that there is no one diet that is suitable to all cases of constipation. For the ordinary indi- vidual it is a mistake to restrict the diet to over- THE INFLUENCE OF HABIT. 5 I refined and highly nutritious foods; nor should the other extreme be followed. A correct blending of coarse and fine foods, with the proper proportion- ment of meats, vegetables, fruits, fats, starches, and sugars, is the diet mosi likely to agree with the intes- tine as well as the stomach. The influence of habit is equally important in evacuating the bowels as it is in the matter of eating. The habit of having a regular daily movement after the morning meal should be cultivated. Irregularity in defecation, usually the result of postponement be- cause of inconvenience, is one of the most successful means of inducing constipation, hemorrhoids, and other unnatural states of the intestine. Few realize that the digestive apparatus is under a sensitive nervous control, and does not tolerate unphysiologic treatment without most appreciable resentment. While infrequency in defecation is evidently harmful, over- frequency is also to be condemned. For the colon to contract naturally and successfully it should have a certain amount of contents of a sufficient con- sistency. Such conditions stimulate a regular and progressive contraction of the bowels and a successful result. In children the amount of effort put forth, the time required for defecation, and the form, quantity, and character of the evacuation should be carefully observed. The dejections are normally more frequent in the young than in the adult. Yet even in children .he habit of going to stool several times during the day should be discouraged. There is a certain rhythm necessary in most physiologic processes, and this is so true of the digestive tract that disregard of the impulse for physiologic defecation is to establish irreg- ularity and usually suffering. HYGIENE OF THE SKIN AND ITS APPENDAGES* By HOWARD FOX, M. D., OF NEW YORK, Clinical Professor of Dermatology, New York Polyclinic Medical School. ANATOMY AND PHYSIOLOGY. The skin is composed of two layers, a superficial thin layer, called the epidermis or cuticle, and a deep layer, known as the derma cutis or true skin. The epidermis is readily separable from the derma, and is the portion of skin that is raised by the fluid of an ordinary blister. Its chief function is to give protection to the underlying true skin and to prevent it from drying and losing its natural softness and pliability. The epidermis has little or no sensibility, and in this respect differs from the true skin, which is remarkably sensitive from the presence of many deli- cate nerve-endings. The deeper layer of the epider- mis consists of cells which are polygonal in shape and moist in character, and is called the mucous layer or rete mucosum. The superficial cells are dry and flattened, and constitute the horny layer of the epidermis. There is a constant production of new cells in the epidermis taking the place of other cells, which are pushed toward the surface and finally shed by the skin. This process of shedding the superficial dry scales is constantly taking place, and is aided by the rubbing of the clothing against the skin and by the friction employed in bathing. This desquamation 52 THE EPIDERMIS. 53 takes place in the form of minute scales. Only upon the scalp do they tend to become visible to the eye and appear as flakes, forming a condition commonly known as dandruff. This physiologic shedding of the epidermis when not in excess is to be aided by bath- ing the skin and shampooing and brushing the scalp. Subcutaneous tissue Fig. io. — Vertical microscopic section through the skin. In the deep portion of the mucous layer of the epi- dermis is situated the pigment, which is the cause of the color of the skin. There is an old adage that "color is only skin deep," but in fact color is only one-half skin deep. The various colors of the skin of the different races of mankind are due to the varying amount of pigment in the deep layer of the epider- mis. Under the influence of the sun's rays pigment 54 THE SKIN AND ITS APPENDAGES. seems to be most readily produced. Not only are races living in the tropics as a rule much darker than the inhabitants of a cold climate, but in this temperate climate is noticed, in the form of tan and freckles, an increased production of pigment oc- curing in summer. Occasionally the function of forming pigments ceases, and the diseases known as vitiligo and albinism result. Vitiligo is character- ized by white spots, most frequently seen on the backs of the hands, while the condition known as albinism consists of a total absence of pigment in the skin, hair, and eyes. The opposite condition, however, is more common, namely, the production of too much pigment, as seen in the formation of freckles and the so-called " liver spots" or "moth patches." The True Skin (Derma). — The under surface of the epidermis is uneven and dips down between the prominences of the derma known as papillae. The true skin is the organ of sensation, and the nerve-end- ings giving rise to sensations of touch, pain, and tem- perature are contained in these little hillocks or papillae. The deeper parts of the skin, together with the underlying fat, serve as a protection to the body against violence. The glands in the skin are of two systems — the perspiratory and the sebaceous or oil-producing. The perspiratory glands consist of little tubes ending in coils lying deep in the true skin or in the fat beneath. An outlet or duct runs in a spiral man- ner to the free surface of the skin. These glands, or pores, as they are popularly termed, are found every- where on the surface of the body and are present in very great numbers. It has been calculated that the THE PERSPIRATORY GLANDS. 55 entire number of glands, if placed end to end, would cover a distance of twenty-eight miles. Next to the kidneys the perspiratory glands are the chief means of removing water from the system, and in addition carry away various other waste-products. Besides being an organ of excretion, the skin, by means of its pores or perspiratory glands, performs the important function of regulation of the body-temperature. Fig. II. — Vertical section of skin : sbg, sebaceous glands ; ep, epidermis ; h, hair; d, derma. When the body is at rest or only slightly in motion perspiration is constantly taking place in the form of a vapor, and is spoken of as being insensible. When, however, considerable exercise is taken the pores be- come more active and produce a visible amount of perspiration, which is termed sensible. The condition of the atmosphere greatly influences the activity of the glands. If the air is saturated with moisture, the $6 THE SKIN AND ITS APPENDAGES. perspiration does not readily evaporate, but remains upon the body. If the air is dry, and especially in motion, the perspiration readily evaporates and be- comes insensible. When the surrounding air is much warmer than the body the vessels of the skin dilate, free per- spiration takes place, and by its evaporation the body becomes cooled. If the air is already full of moisture, evaporation of the perspiration becomes very difficult, and we suffer more from heat than if the air were dry. This phenomenon of finding hot weather most uncomfortable when humidity is pres- ent is known to all through disagreeable experience. It is for the same reason that a much higher tempera- ture can be born in the Turkish bath where the air is dry than in the hot vapor or Russian bath. When the air is cooler than the body the blood-ves- sels contract and retain the warmth of the body by lessening the amount of blood in the skin to be cooled. Considering the purposes subserved by the perspiratory glands, it is highly important to remove the dry scales of the epidermis which constantly accumulate and interfere with their free action. While this is par- tially accomplished by the friction of the clothing, nothing will take the place of systematic bathing if we desire to keep the skin in a perfectly healthy con- dition. While the perspiratory glands give out moisture, it is not probable that they absorb any appreciable amount of water from without, as experiments attempting to show an increase of weight after long- continued immersion in water have proved incon- clusive. The same is true of salt in solution, and THE OIL-PRODUCING OR SEBACEOUS GLANDS. 5/ the efficacy of sea-bathing in giving and maintaining health and vigor is due to causes other than the absorption of salt. The oil-producing or sebaceous glands are found in all parts of the skin, with the exception of the palms and soles, and are especially abundant on the face. Under the microscope they appear like small sacs situated more superficially than the perspi- ratory glands, and opening in most cases into the Fig. 12. — Transverse section of skin from scalp, showing hairs cut transversely : ep, epidermis ; h, hairs ; sbgl, sebaceous glands. little pits for the hairs known as the hair- follicles. They secrete a greasy substance, for the purpose of lubricating the skin and keeping it in a soft and pliable condition. The special oil-glands of the eye- lids prevent adhesion of the lids, while those in the scalp form a natural hair oil or pomatum. The oil- glands prevent injurious friction of opposing sur- faces, and the oily secretion in general tends to pro- tect the body from moisture, as it does in the case of feathered creatures. 58 THE SKIN AND ITS APPENDAGES. Although the hair and nails appear to be entirely different in structure from the skin, they are merely modifications of its horny layer. The hair consists of a shaft which appears above the surface of the skin, and a root which is placed in Hair-shaft Epidermis Sebaceous gland Medullary substance of hair-shaft Cortical substance of hair-shaft Inner root-sheath Outer root-sheath Hair-bulb Hair-papilla Fig. 13. — Section through hair and foUicle. a socket or inversion of the skin, called the hair-follicle. At the bottom of the follicle the hair and the various layers of the skin are found to be THE HAIR. 59 continuous. The substance of the hair consists of three different layers, and has been compared to the trunk of a tree. The main portion of the hair, the fibrous portion, is comparable to the dense wood of the tree, and consists of flattened and elongated cells. It constitutes the main bulk of the hair. The central portion, or pith, consists of cells nearly spherical in shape. The outermost layer of the hair consists of flat cells which overlap one another like tiles on a roof, and to this fact is due the rough feeling when a hair is pulled between the fingers from the point toward the root. The property of " felting" is also due to this peculiar saw-like surface of hair. By the same arrangement a loose hair may at times work its way into a wound. The color of hair depends upon the presence of pigment in the pith and fibrous layer, and upon the presence of minute bubbles of air. The greater part of the body is covered with fine, downy hairs, whose roots extend but a short distance in the skin, while the roots of the large stiff hairs extend into the fat beneath the skin. The hair serves various useful purposes, besides being a very great adornment to the human body. It protects ihe head against the sun's rays and against violence, and affords a very considerable amount of warmth. The eyelashes protect the eyes against the entrance of foreign matters, and the stiff hairs of the ear and nose prevent intrusion of insects and foreign bodies. The moustache is supposed to act as a filter of the air that is breathed, while the beard is said to serve the purpose of protecting the throat from cold. 6o THE SKIN AND ITS APPENDAGES. The nail consists of modified, horny tissue lying upon the nail-bed, which is a portion of the true skin. The nail itself corresponds to the epidermis in this region. The sides and root of the nail are embedded in folds of skin, while its end is free. Near the root of the nail is seen a semilunar area, which is more opaque than the rest of the nail, due to a scarcity of blood-vessels in this situation. The nail itself has no color and is bloodless. Its apparent color is due entirely to the vascularity of the nail-bed beneath, which shines through the translucent substance. The growth of the nail takes place at its root by constant formation of new cells pushing the nail forward. If, however, an obstacle to its forward growth is offered by a tight-fitting shoe sooner or later the nails will begin to grow into the flesh, and the painful condition of ingrowing nail will be the result. The discussion of the hygiene of the skin naturally involves a number of important subjects, prominent among which are food, exercise, bathing and clothing. As food and exercise are treated else- where in this work, it need only be mentioned here that the maintenance of the skin in a healthful condition depends largely upon a judicious dietary and systematic exercise, while the attention of the reader is particularly invited to the subjects of regular bath- ing and proper clothing. BATHING. While discussing the physiology of the skin it was shown how the superficial scales of the epidermis tend to collect, and with the sebaceous matter and BATHING, 6 1 dirt to form a pellicle which interferes with the proper functions of the perspiratory glands. Bathing re- moves this pellicle and is an important factor in maintaining a healthy skin. In addition it has a very beneficial effect upon the general health, as the skin is intimately connected with the internal organs by means of the nervous system. Classification of Baths. — Baths are often spoken of as local or general, according as the ablution is confined to a portion or the whole of the body. Again, they may be classified according to tempera- ture as follows : hot, over 98°F ; warm, between 90° and 98° F. ; tepid, between 80° and 90° F. ; cool, be- tween 65° and 80° F. ; and cold, below 65° F. These are merely arbitrary, but convenient distinctions. For practical purposes it will be sufficient to describe the cold, the warm, and the tepid bath. The cold bath is intended to act as a stimulant and give strength, as opposed to the warm bath, which has a soothing action, or, technically speaking, is sedative. The proper time to take a cold bath is before breakfast and as soon after ris- ing as convenient. A simple and by no means in- effective way of taking the morning bath is with the sponge, for the conveniences of a shower bath or tub are not always at hand. Every one, however, may possess a sponge and a bowl of cold water, and will derive health and enjoyment from their daily use. Considering the fact that cold baths are so bene- ficial and pleasant, as those who take them regularly will affirm, it seems strange that in this country at least such a small number of persons indulge in them. Many say that they cannot take the cold bath. 62 THE SKIN AND ITS APPENDAGES. as it gives them too great a shock, or is too weak- ening, or is not followed by a proper reaction. On the contrary, however, most persons can take a cold bath every morning if they will only make up their minds to do so and go about it properly. It would not, of course, be advisable for one advanced in years, when the blood-vessels are naturally weak, to risk apo- plexy by plunging into a cold bath without being properly trained to it by gradual stages. The physiologic action of the cold bath is to con- tract the cutaneous vessels and to drive the blood to the internal organs, causing a pallor of the skin. The respiration is greatly increased in depth, quick- ened at first and then slowed. The frequency of the pulse is lessened and the temperature somewhat lowered. The nervous system and especially the mental faculties are immediately and very power- fully stimulated. Upon emerging from the bath, if the reaction takes place, the tiny arteries dilate and cause the skin to be flushed, the pulse and respira- tion soon become normal, and the bather experiences very quickly a sensation of warmth and general well- being. This reaction is the test of prime importance as to whether or not the bath is well borne. With practised bathers it will take place very speedily, and a delightful feeling of warmth will very soon be the reward of having for a moment braved the cold water. After leaving the bath, in order to aid the reaction the bather should rub the body from head to foot with a rough towel till the skin fairly glows, and when entirely dry the clothing may be put on without delay. While most persons are able to take cold baths, THE WARM BATH. 63 they should become accustomed to them gradually. Not only will well persons maintain their health and strength, but many in poor health, and especially those of a nervous temperament, will derive much good from the daily cold bath. The best time to be- gin systematic cold bathing is in the warmer months, and by the time winter arrives they can be kept up with very little trouble or discomfort. If the bather has not the conveniences of a tub, or fears such a decided change as a tub bath, it is well to begin with a cold spong-e bath. The sponge should be saturated with cold water and squeezed over the arms, then over the chest and back, and finally over the legs, after which a vigorous rubbing should be taken. The tempera- ture of the water can be raised somewhat at first, and gradually lowered as the bather becomes more ac- customed to the cold water. The temperature of the water should not be so extremely low, however, as to interfere with a thorough and speedy reaction. A very beneficial way of taking the morning cold bath is by means of the shower, which is stimulating through the impact of the water against the skin as well as through its temperature. Nothing quite equals the full tub bath, however, if the bather will begin with water only moderately cold, or will first become ac- customed to the sponge bath, and then change to tub baths. One of the most benefical results of cold baths is the almost universal immunity to catching cold, as every one who takes a cold bath daily will declare. The Warm Bath. — The cold and the warm baths are almost directly opposite in their physiologic action and purposes. The warm bath dilates the 64 THE SKIN AND ITS APPENDAGES. tiny arteries, as is shown by redness of the skin, and causes profuse perspiration. The pulse and respira- tion are increased in frequency and the temperature is raised. The warm bath has an extremely soothing effect on the nervous system, and for this reason is best taken at night before retiring. The perspira- tion which is likely to continue after a warm bath is disagreeable to some, and may be prevented by spong- ing the body with cold water at the end of the bath. After an unusual amount of physical labor, when the muscles are sore and aching, nothing is more wel- come or soothing than a warm bath. The blood is withdrawn from the muscles, lessening chemic change, and pain and soreness vanish speedily. In addition to removing muscular soreness and pain, the warm bath is relaxing and tends to relieve spasmodic conditions or cramps. For those who suffer from difficulty in getting to sleep, a warm bath just before retiring will often invite a refreshing slumber. While the warm bath is to be highly recommended as a means of relieving weariness after prolonged physical exertion, under no circumstances should a cold bath be taken at this time. The hot bath (above 98° F.) should not be taken except upon the advice of a physician. The tepid bath has no decided physiologic effect and is generally employed for cleansing purposes. It may be taken any time during the day, though pref- erably in the afternoon or just before bedtime. The proper time to bathe is just before a meal or about three hours after. In order to digest food properly the stomach needs an abundant supply of blood to form its necessary juices and ferments, and SOAP. 65 if the blood is diverted from the vStomach to the sur- face of the body by means of a bath the digestion will necessarily suffer. Soap. — As water alone cannot dissolve the grease upon the skin, the use of soap is essential in order to effect a thorough cleansing. Soap is a combination of a fat with an alkali in greater or less excess. The latter combines with the fat of the skin, rendering it soluble and freely miscible with water. Potash is the alkali used to form soft soap, while a hard soap is produced by combining the fat with soda. A soap is said to be neutral when the alkali nearly balances or is in very slight excess of the fat, and in this class are included most of our ordinary toilet soaps. A good soap should be made of pure and fresh fat, should not contain too much alkali, which tends to irritate and ^oughen the skin, and the percentage of water should not be so high as to cause unnecessary waste. Adul- teration with foreign substances, such as silica, which is added to increase the bulk, should be avoided. The harm actually done by impure soaps is very small in proportion to the amount of fear and appre- hension expressed concerning their use. No one stops to ask just what special make of bread is pure, but continues to eat whatever bread appears to be wholesome and palatable ; and similarly any toilet soap upon the market may be used with impunity by the majority of people. A soap that will form a large amount of lather is not on that account valu- able, for cocoanut oil is often added to produce this result. The expense of a soap is a better test of its value, as a good soap cannot be made very cheaply. The various soaps that are claimed to have soothing 5 66 THE SKIN AND ITS APPENDAGES. properties are not to be recommended on that account, as the most that is desired of a soap is that it shall be simply pure and non -irritating. Medicated soaps are of little use, although great hopes were expressed as to their usefulness when first introduced. No special therapeutic value can reside in a substance like soap which is intended to come in contact with the skin for such a short space of time. Tar soap has attained a considerable popularity, espe- cially for use in shampooing the head. For this pur- pose it is generally pleasant and effective, but with the exception of a strong odor it cannot be said to possess any very unusual quality. Sea-bathing. — There are numerous causes that tend to make sea-bathing beneficial to the health, as well as a pleasure to the majority of people. The very fact that a bath in the ocean is enjoyable will increase its beneficial effect, and, indeed, any exercise or recreation will be of greater benefit if undertaken cheerfully and not considered as a tiresome matter of duty. The fine, pure air of the seashore constitutes one of the important advantages to be derived from sea-bathing. Breezes from the ocean are always fresh and free from micro-organisms, and constitute an invigorating tonic for healthy as well as for many sickly persons. The shock of the cold bath is always lessened by the exercise taken, especially if the bather can swim. The motion of the waves acts as a sort of massage to the body and adds invigoration to the bath. It is rather doubtful whether any special virtue resides in the large amount of salt and greater density of sea water. It has been remarked that very little if THE TURKISH OR HOT-AIR BATH. 6y any salt can be absorbed through the skin, and this alleged advantage of sea-bathing is probably mostly in the mind of the bather. Many persons abuse the privilege of bathing in the ocean by remaining in the water until their fingers and lips are blue and teeth are chattering. All are not alike in their ability to bear cold water, and convalescents or persons with serious organic disease should bathe only under medi- cal supervision. No one should remain in the bath until thoroughly chilled. Ten to twenty minutes should constitute the range of duration. No one should attempt to plunge into the water suddenly when overheated, and if there is any con- siderable perspiration it is well to sponge off the body with cold or cool water before beginning the bath. The morning is the most appropriate time to take the daily bath in the ocean, as its general purpose is to be invigorating, and it is also most conveniently taken when the water is at high tide. After bathing in the salt water many find it agreeable to take a brief shower or sponge bath of fresh water. When the bath-house is provided with an inner courtyard it is healthful and advisable for the bather to lounge about in the sun for a while and allow the air as well as sunlight to come in contact with the skin, and then to don the clothing leisurely. The word ' ' bath ' ' does not always refer to an ablu- tion with water, but in a broader sense means surround- ing the body with any medium whose quality or tem- perature is unusual. Thus we speak of the hot-air bath, the hot-vapor bath, the compressed-air bath, etc. The Turkish or hot-air bath serves several useful purposes, and is well borne by the average healthy 6S THE SKIN AND ITS APPENDAGES. person. Its systematic use may at times be advan- tageous, although it is for many an expensive luxury and not accessible outside of cities. In taking a Turkish bath, the bather, after removing his clothing, enters the warm room where the temperature is only a little above that of the body. Here he remains for a short time till a gentle perspiration appears upon the skin. He next enters the hot room, where the temperature ranges from 120° to 140° F., and some- times a still hotter room is provided where the tem- perature may exceed 170° F. Upon entering the hot room the inexperienced bather often feels a sensa- tion of nausea or suffocation; but, as a rule, in a well- ventilated bath these uncomfortable feelings will van- ish with the appearance of a free perspiration. A practised bather will suffer no inconvenience in the hot room, and will perspire much more freely and much more quickly than the beginner. By drinking a glass of water before or during the bath the produc- tion of perspiration is greatly aided. After leaving the hot room the bather is shown to a moderately cool room and reclines while the attendant lathers him from head to foot and scrubs and massages him vigor- ously. This removes all the dried epithelial scales, and as a means of cleansing the skin it may be said that the Turkish bath is without an equal. The soap is removed by a douche, beginning with warm and ending with cold water. The bather may then take a plunge in a tank of cold water if this is afforded by the establishment, or immediately repair to a cool room and recline for a half hour or more wrapped in a blanket. For persons who are exhausted from great exertion and whose muscles and joints are sore BATH-PRURITUS, 69 and stiff the Turkish bath is most refreshing. Many sufferers from rheumatism will derive relief from a systematic course of such baths. The Turkish bath is often successfully resorted to for breaking up a cold. The Russian bath differs from the Turkish bath in substituting hot vapor for the hot air of the latter. Perspiration cannot take place as readily in the Rus- sian bath as has been explained, and for producing a copious perspiration the Russian bath is inferior to the Turkish. It is employed in some cases of chronic rheumatism, and is especially beneficial for dry forms of bronchitis. Bath-pruritus. — A recent writer speaks of a dis- agreeable and annoying result occasionally produced by bathing, which he calls "bath-pruritus." He de- scribes it as a sensation of burning, or more often itch- ing, chiefly confined to the lower extremities, which appears very shortly after an ablution. Its duration varies from a few minutes to a half hour. It may follow bathing in salt or in fresh water. The itching seems to be aggravated by too long continuance or extremes of temperature of the bath; by the use of soap that is too strong or is allowed to remain upon the skin. Indulgence in scratching seems to increase the pruritus. The writer further states that the affec- tion is likely to occur in persons with a naturally irritable skin and a tendency to urticaria or hives. This statement suggests sufficient cause for the majority of cases of this so-called bath-pruritus. In- deed most persons who suffer from itching after a bath must look for the cause in a natural irritability of the skin rather than in the bath itself JO THE SKIN AND ITS APPENDAGES. The treatment, which is not always satisfactory, is based upon general principles. Any digestive or nervous disturbances are to be corrected, and a re- stricted diet and plenty of exercise are to be advised. The intestinal action should be rendered free by lax- ative food or medicine. The bath should not be of too long duration, and for cleansing the skin a good toilet soap should be employed. After the bath it is well to dry the skin gently without friction, and then to apply freely some dusting-powder, such as equal parts of starch and zinc oxid. Care of the Complexion. — From the exposure to which the face is naturally subjected it should receive no less than two daily ablutions. Cold water should be used for washing the face, as it has a stimulant action on the blood-vessels and improves the circula- tion in the skin. It also improves the tone of the elastic fibers of the skin and tends to delay the appear- ance of wrinkles. Furthermore, the general sensa- tion of bathing the face with cold water is most refreshing. If the water is so cold as to be disagree- able, its temperature may be raised slightly ; but it is not advisable to use hot or warm water regularly for washing the face. Using hot water upon the face and then undergoing exposure to cold air or wind, especially in winter, has a decided tendency to pro- duce chapping and roughening of the skin. It is a question as to whether the use of soap is advisable for the daily cleansing of the face. For the perfectly healthy skin soap is not absolutely essen- tial, and its too frequent use may prove injurious. For persons, however, with a ver>' oily skin, or for those residing in cities where the air is laden with TOILET LOTIONS. 7 1 soot from the use of soft coal, the daily use of soap may be necessary. If the complexion is sallow and there is a tendency to pimples and blotches, nothing will serve better to stimulate the circulation and to improve the comxplexion than vigorous pinching of the face by the fingers. Questions are frequently asked regarding the advis- ability of using various toilet creams and lotions on the face, and about the use of the various complexion or face powders. If the skin is unnaturally dry, there can be no harm in the application of a little grease to the face, while the employment of powder is largely a matter of taste. In hot weather the application of a small quantity of rice powder to the face will often be grateful, and can do no harm to the complexion. The preparations known as cold creams are mixt- ures of some solid fat as wax or spermaceti, with an oil such as castor or almond oil, to which some fragrant substances are added. They can be used on the face with perfect freedom and without danger of injury. The toilet or face creams are mucilaginous preparations containing tragacanth and other ingre- dients, and are pleasant applications for a fissured or chapped skin. Toilet lotions serve a similar purpose, and are gen- erally transparent preparations containing glycerin and other substances. For removing summer freckles and tan the follow- ing lotion may be employed : B. — Sulphocarbolate of soda, 50 grains ; Glycerin, 2 ounces ; Rose-water, I ounce ; Alcohol, I ounce. 72 THE SKIN AND ITS APPENDAGES. For an obstinate case of freckles the following may be recommended : R. — Bichlorid of mercur>^, 6 grains ; Alcohol. I ounce ; Glycerin, 2 ounces ; Oil of lavender, 10 drops. Face powders are generally composed of one or more of the following substances : Talcum, starch, bismuth, chalk, zinc oxid, and magnesia, and, as a rule, are entirely harmless. Lead has at times been employed as an ingredient of face powders, and if the powder contains this substance it is objectionable from the possibility of a poisonous effect. CLOTHING. The materials most frequently used for clothing are derived partly from the animal and partly from the vegfetable kins^dom. From the former are obtained silk, wool, furs, and leather, while from the latter are derived cotton, linen, and rubber. In discussing the value of these different substances as materials for clothing, two important physical properties to be considered are their power of conducting heat and capacity for absorbing moisture. The heat-conducting power which a garment possesses does not depend to an}- great extent on the fabric itself, but chiefly on the manner in which that fabric is woven. Dry air is a very poor conductor of heat, and any garment which is loosely woven and is capable of holding considerable air in its meshes will be a poor conductor, and will consequently feel warm. Wool, for the reason that it is naturally woven into cloth that is loose in texture and porous, is a most CLOTHING. 73 valuable clothing material for use in cold weather. If numerous thicknesses of woollen clothing will not suffice to withstand severe cold, then furs may be supplemented. Cotton is naturally woven into cloth whose texture is compact and not porous, and is, therefore, not so valuable as wool for use in cold weather. When, however, specially manufactured so that its texture closely resembles that of woollen cloth, it may be a fair substitute for wool. The capacity for absorbing moisture is possessed by wool to a very high degree, silk being next to wool in this respect. Linen is only moderately, and cotton very slightly, hygroscopic. A woollen gar- ment has the property of absorbing a great deal of moisture without feeling wet. Evaporation of moist- ure proceeds slowly from woollen clothing, while cotton clothing, especially underwear, speedily becomes saturated with moisture and evaporation is liable to take place suddenly, with resulting chilling of the body. In speaking of flannel, some philosopher has made the paradoxical remark that no matter how cold and wet it may be it is always warm and dry. As flannel underclothing is so hygroscopic and does not allow the moisture it absorbs to evaporate too rapidly, it is the most valuable material for under- clothing for use in temperate and changeable climates. For cold weather, heavy woollen underwear cannot be surpassed for warmth and comfort. By manufactur- ing cotton into cloth with large meshes or air-con- taining spaces a very fair substitute for flannel underwear has been obtained. While probably not superior to flannel for underclothing, this material is valuable for persons who find wool next to the skin 74 THE SKIN AND ITS APPENDAGES. uncomfortable. Many, however, who think at first that they cannot bear wool next to the skin will, after awhile, tolerate its presence. Another substi- tute for woollen underwear is found in merino, which consists of a mixture of wool and other materials. Woollen underclothing has the disadvantages of shrinking readily when washed and of absorbing odors readily. The former fault can be somewhat overcome, however, by buying goods which have been shrunken and by having them washed in tepid water, with little soap and no violent friction. On account of this tendency to shrink, old flannel under- clothing is not the equal of new, for after repeated washing the fabric becomes " felted," less porous and of a closer texture, and consequently not so warm. Clothing for Cold Weather. — It is a mistake to try to endure cold weather without wearing suffi- ciently warm clothing. Whenever a feeling of cold or chilliness is experienced it is highly proper to put on an extra garment without delay, and it is folly to w^ait till the body is chilled before taking the trouble to make a change of clothing. The habit of wearing thin clothing all the year round and of going without an overcoat through the winter to dis- play a vigorous constitution is not advisable. It is true that some persons seem to keep well from such a course, and while the heat-producing power may be equal to the extra demand, it is at the expense of the nervous energy of the individual. Children and old people, whose power of producing heat is lim- ited, should be proportionately warmly clad, and the practice of dressing children with the legs exposed is as cruel as it is unhygienic. CLOTHING FOR WARM WEATHER. 75 Clothing for Warm Weather. — For use in tropical climates flannel underwear is found to be too warm, and cotton, silk, and linen are more serviceable ma- terials. The Chinese plan of wearing a net next to the skin, and over it a thin silken garment, is ad- mirable, the silk readily absorbing the perspiration, while the net prevents the silken garment adhering to the skin. Silk underclothing is always agreeably soft and fresh, but it is expensive and is likely to shrink considerably in washing. Much of the under- clothing said to be pure silk is probably of mixed composition. Thin linen for tropical wear is said to be very acceptable and always has a feeling of fresh- ness, but it is more expensive than cotton, which is for practical purposes the most available material to be employed. Cotton cloth is strong, durable, cheap, does not shrink readily, and absorbs odors very slightly. As a protection against excessive heat the color of clothing is of considerable importance. By placing pieces of cloth of light and dark shades upon snow it is found that the snow melts more readily under the dark than under the light cloth. From this we infer that light colors, such as yellow or white, which ab- sorb fewest of the heat rays of the sun, are the more suitable colors for tropical clothing. The presence of cheap aniline dyes in underclothing and stockings will occasionally cause considerable irritation to the skin, though much less frequently than is generally supposed. By observing cleanliness and discarding the offending garment relief will very promptly be afforded. Underclothing should be washed frequently, de- "J^ THE SKIN AND ITS APPENDAGES. pending on the amount of perspiration of the wearer. It should be aired very thoroughly over night, and the same set should never be worn both day and night. Damp underclothes offer a most excellent soil for the growth of micro-organisms, and favor the development of certain parasitic skin-diseases which flourish only under conditions of warmth and moist- ure. Rubber or mackintosh clothing is very useful as a protection against wind as well as rain, and is suit- able for persons whose occupation requires consider- able exposure but not much exercise, as, for instance, coachmen or seamen. For active occupations it is to be condemned. Being impermeable to air, the per- spiration cannot evaporate as readily as it does when woollen garments are worn. There has lately been introduced a form of waterproof cloth that differs from rubber in being entirely permeable to air. Overcoats made of this material will shed rain per- fectly, and, unlike a mackintosh, will feel perfectly comfortable when exercise is taken. As this mate- rial allows free evaporation of the perspiration it forms the ideal waterproof garment. Shoes. — There is hardly an article of clothing upon which our comfort depends to so large an extent as upon the covering of the feet. It seems superfluous to say that shoes should fit the feet perfectly, yet owing to the demands of fashion this does not always seem to be the chief consideration in purchasing shoes. If expense need not be considered, boots or shoes should be made to order. By standing in the stockings a tracing is made about the foot and from this the proper last is constructed. In a well-made pair of SHOES. 77 Fig. 14. — Normal feet (Whitman). FiG. 15. — Proper soles for normal feet (Whitman). shoes the inner sides should be nearly parallel and not diverge greatly when the wearer stands with feet Fig. 16. — Deformed feet (Whitman). Fig. 17. — Shoemakers' soles (Whitman). together. The outer side of the shoe should have a gentle curve inward, and the toe should in no case be yS THE SKIN AND ITS APPENDAGES. pointed. In Fig. 14 is shown an impression made by the normal foot. To provide a sensible form of shoe for a foot of this shape it does not seem rational to have the toe narrow and pointed ; nor, on the other hand, perfectly square as is seen in some of the so- called common-sense shoes. The sole of a properly constructed shoe should have the shape shown in Fig. 15. In Fig. 16 is given an illustration of a foot that has become deformed and made to fit a shoe whose shape is improper and unhygienic (Fig. 17). It is most essential to comfort that a shoe should be sufficiently long. A good rule to follow is to wear shoes that are at least three-quarters of an inch longer than the foot. By observing these common- sense ideas many troublesome conditions, such as corns, bunions, and others more serious, may be pre- vented. The soles of the shoe should be of the extension type if intended for hard walking, as the projecting Fig. 18.— The rocker sole Fig. 19.— The flat sole (Whit- (Whitman). man). part affords considerable protection against loose stones. If the sole is flat, a much better support is given the foot than in the usual sole that turns up from the ground (see Figs. i8 and 19). The leather should be moderately thick for protection, and -at the same time pliable. SOCA^S AND STOCKINGS— GARTERS. jg The heels should always be broad and low. The high heels so frequently worn by women for the purpose of increasing their height and lessening the apparent size of the foot are harmful. They tend to produce weakness of the arch of the foot through atrophy of the plantar ligaments. I^ow shoes are a hygienic form of footwear, since they allow excel- lent ventilation of the foot, and are especially desir- able for use during the warmer months. Patent leather shoes are not advisable for con- tinued wear, since, being impermeable to air, they do not allow proper evaporation of the perspiration from the feet. However uncomfortable rubber shoes may feel, they are probably the means of preventing many colds ; they should never be worn unnecessa- rily. For those who have to do considerable walking in wet weather and cannot conveniently wear rub- bers, hobnails are a great protection to the soles of the shoes, and also add to the firmness of the step. Socks and stockings should often be changed, the frequency depending on the amount of perspira- tion of the wearer's foot. In the case of those who suffer from excessive perspiration of the feet, at times of a bad odor, the socks or stockings should be changed daily. The feet should be washed and dried without friction, and over the feet and in the fresh socks may be dusted the following powder — salicylic acid, i part ; starch, 4 parts. Garters. — Unfortunately, ill-fitting shoes are not the only portions of the human attire that bring about evil consequences and are to be condemned. Any article of clothing which unnaturally constricts a portion of the body is harmful and unhygienic. The 8o THE SKIN AND ITS APPENDAGES. circular elastic garter acts as a constant tourniquet about the leg and interferes with the circulation of blood in the veins. These will tend to dilate after awhile and become tortuous, giving rise to the con- dition known as varicose veins. The dilated veins generally prove to be sources of considerable annoy- ance, and at times of danger. Instead of using circu- lar garters, the proper plan is to suspend the stockings from some part of the underclothing. Corsets. — The subject of improper clothing could not well be passed by without adding a few words to the volume of protest already entered against the wearing of tight corsets. The practice of compressing the body unnaturally by means of various kinds of stays seems to continue in spite of the hostility of practically all physicians. Constrict- ing the waist too tightly causes a change in position and interferes with the functions of many of the in- ternal organs (see page 44). It prevents the proper muscular development of women, as no tightly-laced woman can indulge in any vigorous exercise. Corsets greatly interfere with the fullest attainment of health and vigor. When tightly laced they lessen the amount of air that can be taken into the lungs. As a result the blood is imperfectly aerated, deteriorates in quality, and the wearer suffers from anemia. The entire list of injuries attributed to wearing tight corsets is a formidable one, and should cause every woman to think before continuing the prac- tice. Most women say that they would have a feel- ing of utter collapse if the stays were to be laid aside. This is due to the imperfect development of muscles that are not called into play when stays are BED- CL O THING. 8 1 worn, but which should be strengthened by exercise in order to perform their natural functions. A certain writer has expressed opinions about stays that have given great consolation to women who wear them. She says that women breathe naturally with the chest, especially the upper portion, and employ abdominal breathing very slightly, so that tight lacing which does not interfere with chest breathing is hygienic and proper. Opposed to this view, some experimenter has found that Indian girls who have never constricted the waist by stays breathe with the diaphragm as naturally as do men, and con- clude that the insufficient method of breathing with the chest, common in women, is itself due to the habit of wearing stays. As a matter of fact, no skilled singing teacher would ever consent to allow his pupils to sing when handicapped by a tightly- laced waist, but would insist upon their breathing to their utmost capacity. This can only be accom- plished when both chest and abdomen are free and unhampered. Bed-clothing should not be unnecessarily heavy. A light covering, such as an eiderdown quilt, will afford more warmth than a blanket of greater weight, owing to its capacity for retaining more air in its meshes. Similarly two coverings will be warmer than one which is equal to both in thickness, on account of the layer of air contained between them. Bed-clothing should be aired thoroughly every morn- ing, the windows of the sleeping-room being opened for this purpose. %Q,U'^ 82 THE SKIN AND ITS APPENDAGES. CARE OF THE HAIR. A fine head of hair is a possession universally prized, and one which is frequently neglected by its owner as often through ignorance as through care- lessness. In the preservation of the hair some per- sons have a great natural advantage over others. If there is an inherited tendency to baldness, as shown by a thin and poorly nourished scalp, there will be greater difficulty in preserving the hair than other- wise. The scalp is comparable to the soil. Neither hair nor plants will grow luxuriantly if the quality is poor. A scalp which is favorable to the growth of hair is thick and pliable, and moves freely over the bones of the skull beneath. If the scalp is very thin, the blood-vessels contained will be few in number. If it is drawn tightly over the skull, it will tend to con- strict the blood-vessels, lessen the supply of blood to the scalp, and cause atrophy of the roots of the hair from pressure. The two principal causes which bring about a premature thinning of the hair are a deficient circulation of the blood in the scalp and the constant presence of dandruff. Dandruff is a collection of epithelial scales mixed with dried sebaceous matter, and is the forerunner of premature baldness in a large percentage of cases. It will be present to a greater or less degree in many scalps unless it is constantly guarded against. It is highly important to keep the scalp perfectly clean and free from dandruff, and to attain this end daily brushing of the hair and frequent shampooing are necessary. CARE OF THE HAIR. 83 Hair-brushes. — The hair should be brushed morn- ing and night for several minutes until there is a feeling of warmth in the scalp and all particles of dandruff are removed. For an adult the brush should be a stiff one, with the little tufts of bristles widely separated to facilitate cleaning. For children and for those with very sensitive scalps, softer brushes must be used. Brushes should never be so stiff nor the brushing so vigorous as to produce any soreness of the scalp. Brushes should be frequently washed in water containing a little ammonia, and then dried in the sun with the bristles down. Combs are chiefly useful for disentangling snarls and dressing the hair, and may be employed daily with the brush. The teeth of the comb should be wide apart, have blunt ends, and be free from any irregularities which might tear the hair. In no case should the old-fashioned fine-toothed comb be used, as this pulls out the strong hairs, especially if the growth is luxuriant, and the fine points may produce disease of the scalp from irritation. Many persons are morbidly afraid that any consid- erable amount of brushing and combing will cause a serious loss of hair. Its effect, however, is just the opposite and increases the growth of hair by stimu- lating the circulation in the scalp and by removing dandruff. Brushing removes many loose hairs which are ready to fall, but their place will soon be taken by new and more vigorous ones. The groom knows by experience that the only way to keep the coat of his horse thick and glossy and in a healthy condition is to constantly use the currycomb and brush, and that he is not likely to use either too much. 84 THE SKIN AND ITS APPENDAGES. Shampooing. — Many persons who are favored by nature with a luxuriant growth of hair and who per- haps consider themselves immune to baldness, will grudgingly give any time to the care of the hair and consider shampooing especially distasteful. To keep the hair clean and free from dandruff, shampooing at intervals is very necessary. There are many popular fallacies concerning ques- tions of physiology and hygiene, and some ideas about shampooing of the scalp are no exception to the rule. Shampooing, like brushing, also removes some loose hairs, but by cleansing and stimulating the scalp it forms a most important means of preserving a good head of hair or aiding to restore it after a tem- porary falling. The frequency of shampooing of the scalp depends on the rapidity with which dandruff accumulates, and to some extent on occupation of the individual. For some persons, washing the scalp once a month will be found sufficient to keep it in a hygienic condition. Others, and especially those whose business requires much travelling or exposure to dust and dirt, may find it necessary to wash the head once a fortnight, or even once a week. There is never any danger of shampooing the healthy scalp too frequently, notwithstanding the opposite state- ment so frequently made by some hairdressers, whose chief stock in trade is some *^ tonic ^* of alleged miraculous virtue. When the hair has begun to fall out prematurely, due to long neglect or following an illness, it is well to begin shampooing the head twice or even three times a week, and to gradually lessen the intervals to once in three or four weeks. Not only are some afraid that the shampoo will SHAMPOOING. 8$ cause considerable loss of hair through the friction employed, but they fear that all the oil in the scalp will be removed and great damage done to the hair by the dryness resulting. Immediately after washing the scalp, especially if alcohol be used in addition to the soap, the scalp will certainly feel dry, but it will soon become more oily than usual due to improve- ment in circulation and consequent stimulation of the oil-glands. This will be the result in the majority of cases, and very few persons will suffer from dryness of the scalp if they practice shampooing with suffi- cient frequency. Some persons actually say that after the shampoo the scalp becomes too oily. When the scalp fails to respond to the mechanical stimulus of shampooing by producing an insufficient amount of sebaceous matter, then it is well to rub into the scalp some form of grease or oil. Nothing answers the purpose better than pure vaseline, although some barbers prefer to use olive oil. This can be con- veniently applied by a medicine-dropper, after making numerous parts in the hair. The use of soap on the hair agitates many persons who, though employing the best soap in cleaning the skin, consider that shampooing is a dangerous procedure unless the soap used is recommended by physicians. Any good toilet soap upon the market will answer the purpose, and more harm is done by refraining from the use of the shampoo than by using an inferior quality of soap on the hair. The addition of alcohol to shampooing liquids, as in the tincture of green soap will greatly assist the thor- ough cleansing of the scalp. The addition of an ^^% to the shampoo is thought by many to make it more 86 THE SKIN AND ITS APPENDAGES. pleasant and effective. As the ^gg has no cleansing effect its use is largely a matter of taste. There is no more reason for its employment upon the scalp than for its use in the daily washing of the hands and face. A very satisfactory shampoo liquid is found in the linamentum saponis mollis of the Pharmacopeia, which consists of 50 parts of soft soap, 2 parts of oil of lavender, and 33 parts of alcohol. In the operation of shampooing any ordinary good toilet soap may be selected. A lather is then formed and rubbed vigorously into the scalp with the finger tips or a stiff brush, a nail brush being very conve- nient for the purpose. The lather is best removed by a warm-water douche, always ending the process with cold water to lessen the danger of contracting a cold. The hair is then to be dried as thoroughly as possible with towels, and to complete the drying it is well to remain for a while in the sun or near an open fire or radiator. Head-gear. — While many persons naturally possess a thin head of hair and a poor circulation, they are handicapped still further by various causes that tend to lesson the circulation in the scalp. One of these causes is the wearing of hats. The hats worn by men at the present time, especially the Derby and silk hat, allow very little ventilation, prevent the access of sunlight as well as air, and do not permit the proper evaporation of the perspiration. The tight-fitting brim also constricts the blood-vessels and hinders the circulation. Women's hats have no tight brim, allow free ventilation, and, unless very heavy, are seldom objectionable in this respect. The interesting and MASSAGE OF THE SCALP. 8/ oft-repeated arguments against the wearing of hats may here be cited. Savages who go bareheaded do not suffer from baldness, and the same immunity to early falling of the hair is said to be the good for- tune of the lads of the "Blue-Coat School'* in London. These boys never wear any hats, however stormy the weather may be nor how low the ther- mometer may descend. As the hats of the present day seem to be necessary evils, the only practical advice that may be given is that they should not be worn unnecessarily, especially when the head is perspiring, and that they should not be jammed on the head with such firmness as to interfere with the circulation of the scalp. The fact that women are more free from baldness than men may be due in a slight degree to their wearing a more hygienic form of head-gear, but undoubtedly the chief cause lies in their possession of a thick scalp and an underlying cushion of fat, which is naturally better adapted to support a good growth of hair. Some physicians think that the amount of brain- work done may be a factor in bringing on premature baldness, but this has not been definitely proven. The answer to the question as to what can be done to improve the circulation of the scalp and the growth of the hair is, briefly — mechanical stimula- tion. This may be practised through shampooing, massage, and the local application of electricity. Shampooing has been considered, and its thorough and frequent practice cannot be too strongly urged. Massage of the Scalp. — Vigorous daily massage, if continued for a considerable time, will tend to im- prove the circulation and to increase the growth of 88 THE SKIN AND ITS APPENDAGES. hair. If the scalp is pale and thin, it is well to com- bine a few minutes of massage by the finger-tips with the daily morning and night brushing. A variety of motions may be practised, such as moving the fingers over all parts of scalp, and then placing them firmly on the scalp and moving the scalp itself over the bones beneath. Electricity acts merely as a local stimulant to the circulation, and is best used in the form of galvan- ism. A wire-brush electrode is attached to the negative pole of the galvanic battery, and applied to the scalp through the hair until the former becomes well reddened. Cutting the Hair. — Many persons entertain the false idea that cutting the hair increases its thick- ness. While it may aid to some extent the rapidity of growth, cutting certainly does not increase the number of hairs. To keep the hair short in chil- dren up to the age of eight or nine years is generally deemed sensible and hygienic. Its good effect is mostly due to the easier access of air and sunlight to the scalp and to the greater ease with which the head can be kept clean, although some think that if the hair of a growing child is kept short there will be 'less of a tax upon its strength and vitality. The opinion seems to be pretty general that shaving with a sharp razor will produce a thicker and firmer growth of hair, although one recent writer on hy- giene claims that shaving actually has a depilatory effect. In the process of shaving, the roots of the hairs are stimulated to a slight degree, and a coarser and thicker growth upon the face of a young man doubtless results in due time ; but time rather than HAIR RESTORERS OR HAIR TONICS— POMADES. 89 shaving is responsible for the change. The experiment occasionally tried by enthusiasts of shaving the head in the hope of obtaining a better growth of hair is never productive of any brilliant result, and may be con- sidered as absurd and useless. In dressing the hair it is important to make no violent traction upon the roots, as this has a ten- dency to loosen and cause a falling of the hair. There should be no twists or knots which produce feel- ings of discomfort for such are certain to prove in- jurious. There is no great objection to curling" the hair if it is not done with too much vigor. Curl papers, if not put on so tightly as to pull on the roots of the hair, are not likely to do harm. Curling irons, however, are often overheated and make the hair un- naturally dry and brittle. A very absurd idea that pervades the mind of the average " tonsorial artist" is that singeing the hair will tend to preserve it and to stimulate its growth. There is no truth in the barber's assertion that the hair is a hollow tube which will allow the escape of oil, and that if the ends can only be sealed by singe- ing much benefit will result. Hair restorers or hair tonics are fully as useless as singeing. These preparations, which are widely advertised, fail utterly to accomplish the purpose for which they are employed. Shampooing, brushing, massage of the scalp, and attention to the general health, and not the use of a hair tonic, are the only means of preserving a good head of hair and aiding its restoration after falling. Pomades are mentioned only to say that their use in general is considered unnecessary, while to most 90 THE SKIN AND ITS APPENDAGES. people they seem uncleanly and disagreeable. A generation ago some oily dressing for the hair was universally used, largely because it was the fashion. Bear's grease was often used as an ingre- dient of the pomade, in hopes that some hair-restor- ing properties might be possessed by the fat of an animal as naturally hairy as the bear. Many young men indulge in the habit of fre- quently wetting the hair in order to make it set smoothly. In addition to producing a doubtful esthetic effect, this practice is harmful by tending to cause decomposition of the roots of the hair. As has been stated, there is no harm in washing the hair frequently if it is subsequently dried with towels. Removal of Superfluous Hair. — The use of de- pilatory, pastes or substances to remove superfluous hairs is not recommended, except upon the advice of a physician. These pastes will often remove a downy growth of hair, but cannot remove large stiff hairs without doing too much damage to the skin to warrant their employment. For removing large hairs, the only satisfactory method is the slow but sure one by electrolysis. By this method an experienced operator can remove any number of large hairs per- manently without leaving any scars or causing much pain. Gray Hair. — An eminent dermatologist has re- marked that the only sensible thing to do for gray hair is to admire it. While gray hair undoubtedly improves the looks of some people and is welcomed by them, it is to others a source of considerable an- noyance. In the rare cases of sudden blanching of the hair, such as sometimes follows profound mental CARE OF THE BEARD. 91 disturbance, a return of the former color is a possi- bility, but even this could not probably be aided by any efforts of the physician. Nothing can really be done to prevent the hair turning gray. Dyeing the hair is an exhibition of poor taste, and is really only excusable in the case of young persons whose hair has turned gray at an unusually early age. Many of the dyes for coloring the hair black contain lead, and on this account should be avoided, as cases of lead-poisoning from the use of hair-dyes undoubtedly have occurred. Before the application of any hair-dye the head should be thoroughly shampooed and then dried. The dye is most conveniently applied to the hair by a tooth-brush, avoiding contact as far as possible with the scalp. Leonard recommends the following harmless hair- dye for producing a black color. B. — Bismuth citrate, i ounce ; Rose water, 2 ounces ; Distilled water, 2 ounces ; Alcohol, Yi ounce ; Ammonia water, a few drops. To be applied in the morning. R. — Sodium hyposulphite, i>^ ounces ; Distilled water, 4 ounces. To be applied at night. To obtain a brown color a mixture of pyrogallic acid and rose water may be used Care of the Beard. — An equal amount of care should be bestowed upon the cleanliness of the beard and mustache, as is shown in the case of the scalp. 92 THE SKIN AND ITS APPENDAGES. The frequent ablutions of the face during the day should include both beard and mustache. To give softness and lustre to the mustache, preparations known as brilliantines may be employed without danger of a harmful effect. A suitable formula for such a preparation consists of glycerin, castor oil, and alcohol in the proportions of one, two, and three re- spectively, to which a proper amount of perfume may be added. In regard to shaving, it may be said that it is always a good plan for a man to practise shaving himself and so avoid any possible danger of infection from the barber-shop. In these establishments a number of diseases may be contracted, notably ringworm. This affection, so obstinate when attacking the hairy por- tions of the body, is usually acquired from the use of a damp towel, less often from the shaving-brush, the "clipper," or the hands of the barber. The razor is not at all likely to be the cause of infection. The damp towel offers a most excellent medium for the growth of the ringworm parasite, as this fungus, like ordinary mould, requires moisture for its development. If a barber-shop is to be patronized regularly, the customer should have a private cup, shaving-brush, and razor. If, in addition, the towels to be used are perfectly clean and dry, and the barber washes his hands thoroughly after shaving each customer, there will be still less danger of contracting ringworm and other infectious diseases. Care of the Nails. — The proper care of the nails depends upon the observance of a very few and sim- ple rules. The portion of skin overhanging the root of the nail tends to encroach too far over the lunula, CARE OF THE NAILS. 93 and is likely to become torn and ragged, giving rise to so-called " hangnails." These offer little open- ings tlirongh which infectious matter may enter and do a good deal of damage, and it is possible for blood- poisoning to result from infection through one of these apparently insignificant lacerations. The epidermis overhanging the root of the nail should be pressed back once or twice a week with some convenient in- strument. For cleaning the nails, nothing but soap, warm water, and the nail-brush should be employed. The penknife should not be used in place of the nail- cleaner, as it scratches the under surface of the nail and makes a place for the lodgement of dirt. The surface of the nail should never be scraped. A word of advice may be given in regard to cut- ting the nails, for it seems that the proper method is not universally known. The finger-nails are most conveniently cut in a curved direction, or they may be filed if this slower method is preferred. A pair of curved scissors is very convenient for cutting the finger-nails, but should not be used for the toe-nails, as these are always to be cut straight across. If, in addition to the proper selection of shoes, this last pre- caution is observed, a great deal of trouble and dis- comfort may be avoided. For removing stains from the nails a solution of acetic acid and rose water, one part of the former to sixteen parts of the latter, may be employed. Oxalic acid is perhaps more efficient for accomplishing this purpose, but its use is not desirable, owing to its poisonous qualities. HYGIENE OF THE VOCAL AND RESPIRATORY APPARATUS. By E. FLETCHER INGALS, M. D., OF CHICAGO, Late Professor of Diseases of the Chest, and of Laryngology and Otology, in the Rush Medical College ; Late Professor of Laryngol- ogy and Rhinology in the Chicago Polyclinic. THE NOSE. The nose is described as consisting of an outer, or facial, and an inner portion ; the latter lying within the skull. The outer nose has a bony framework in its upper portion, consisting of the nasal bones and nasal proc- esses of the upper jaw. The lower half of the outer nose is made of flexible cartilages, supported in the center by the septum, or dividing wall of the nostrils (Figs. 20, 21). The external nose has muscles of great importance in facial expression, and capable of dilating the nostrils during inspiration. The inner nose consists of two lofty air-passages, extending back into the skull as far as the posterior end of the hard palate, or roof of the mouth. Here the nostrils end in a roomy chamber called the naso- pharynx. The inner wall of each nasal passage, or naris, as it is called, is formed by the division of the nostrils, or septum (Fig. 21). This is composed in its back 94 THE NOSE. 95 and upper parts of two bones, the vomer, or plough- share, below, and a thin plate of bone above, called upper lateral, cartilage Lower lateral. cartilage Sesamoid bones Cell tissue Fig. 20. — Lateral cartilages of the nose. the perpendicular plate of the ethmoid bone. These two bones join behind to form a solid wall, but spread- Horizontal pla te 0/ etJi moid Rostrum of ^ sphenoid Vomer Palatal Perpendicular plate of ethmoid Cartilage 0/ septum Lo7ver lateral cartilage Superior maxillary Fig. 21. — Cartilage and bones of the septum of the nose. ing in front include, like a V, the front or cartilagi- nous part of the septum, which fortunately is very flex- 96 vocal axd respiratory apparatcs. ible ; because if it were of bone, fractures of this part of the nose would occur very frequently. The outer wall of the nose is made of a compli- cated bony framework, supporting three ledges or shell-like projections into the nasal cavities, called the turbinated bodies. These bodies consist of thin bone covered with mucous membrane, containing a sponge-like network of blood-vessels, forming what is called erectile tissue. There are three turbinated bodies in each nostril, called the lower, the middle, and Fig. 22. — Anterior nares, showing white deposit of inspired magnesium- powder upon the septum and middle turbinals only. the upper. The lower and the middle extend the whole length of the nasal cavity; the upper along the posterior half only. Underneath the lower turbinate we have the opening of the tube, or duct, conducting the tears from the eye to the nose ; under the middle turbinated body we have the opening to a thin-walled cavity, which hollows out the upper jaw, and is called the antrum of Highmore. This cavity lies immediately external to the nostril. Accessory Sinuses. — There are other bony cavities connecting with the nose in this location, two in the forehead, or frontal bone, and a large number of cells in a very thin bone at the top of the nose, called the THE MUCOUS ME MB R AXE. 97 ethmoid bone. These chambers in the bones of the skull all contain air. The roof of the nose is formed by the nasal bones iu front ; behind this by a plate of thin bone separ- ating the nasal cavity, from the brain. This plate of bone contains many sieve-like holes, which give pas- sage to the filaments of the ner\e of smell, and is called the cribiform plate of the ethmoid bone. A hollow bone back of this completes the roof of the nose ; it is called the body of the sphenoid bone. The floor of the nasal cavity is formed by the hard palate, a thick, massive plate of bone forming also the roof of the mouth. The mucous membrane of the nose is ver^* sensi- tive, having many ner\'es of sensation from the fifth pair of nen'es besides the special nerves of smell, which are found only along the space between middle turbinated body and the septum, in the so-called olfactory' region. A single layer of minute, microscopic epithelial cells covers the surface of the nasal mucous mem- brane, like pavement blocks, each cell having hair- like processes on its free surface, called ciliae. Nu- merous little tubes, called mucous glands, keep the mucous membrane lubricated with mucus. The best known of the functions of the nose is the sense of smell ; but the other functions are more important to the health of the individual. The many folds and narrow passages of the nasal surface warm the air as it passes over them, at the same time sup- plying it with moisture to the extent oi two-thirds saturation. The moist mucous membrane of the nose also catches almost all of the dust that escapes 7 98 VOCAL AND RESPIRATORY APPARATUS, the many hairs, or vibrissae, as they are called, which are placed at the entrance to the nostrils. Whatever dust lodges on the mucous surface is pushed toward the outer orifice by the minute cilise, which are in constant outward motion. With the dust, of course, any microbes entering the nose are also expelled. In addition to this mechanic expulsion, however, the nose probably possesses the power of destroying the bacteria by means of its mucus, which is germicidal, so that only a very short distance within the nostrils the mucous membrane is found compara- tively free from microbes. Obstruction in tiie Nasal Passages. — To keep the nose and the air-passages below it in a healthy state the nostrils must be open for the passage of air. The commonest cause of stopping up of the nose in chil- dren is enlargement by adenoid growtii of a structure called the pharyngeal or Luschka's tonsil, or the third tonsil. This is placed behind the posterior open- ings of the nose, and when enlarged enough, may en- tirely obstruct breathing through it. Practically all mouth-breathing children have this form of obstruc- tion, the external nasal passages being open. If this form of nasal blocking is allowed to persist, it has a very deleterious effect on the development of the inner nose, which from lack of use is retarded in its growth. In such cases the nasal passages at the beginning of adult life are as small as those of a child, while the upper jaw is narrow, producing an ugly protrusion of the front teeth and a characteristic stupid expression. In adults, nasal obstructions are often due to deformities of the septum, which is either much bent to one side or thickened in such a way as to MOUTH-BREATHING. 99 partially close one nostril permanently. Other fre- quent causes of stoppages of the nose of a lasting character are mucous growths called polyps. The common source of nasal occlusion in grown persons is swelling of the nasal mucous membrane. Mouth-breathing, with its attendant evils, is the result of these obstructions to the free passage of air through the nose. Mouth-breathing allows the en- trance of dust and microbes directly to the lower air- passages, larynx, trachea, and lungs ; whereas in breathing through the nose most of these particles are lodged on the nasal mucous membrane and returned to the outer world in the ways mentioned. The bronchi and trachea have ciliated epithelium as well as the nose, and although this epithelium, by means of its waving, hair-like processes, is capable of expel- ling many of the minute foreign bodies that enter the lungs, still some reach the air-cells even under ordi- nary conditions when breathing is carried on with the mouth closed, while mouth-breathing adds enor- mously to their number. In this way the microbes of tuberculosis, pneumonia, bronchitis, influenza, etc. penetrate the lungs more readily than in nose-breath- ing. This is especially true of the rapid and forced breathing accompanying violent exertion. Through the open mouth diphtheria germs reach the larynx or tonsils directly. Closure of one nostril, common in adults, com- pels the sufferer to try heroically to breathe through the other nostril, with consequent rarefaction of the air in the free nasal passage and the pharynx, thus by suction overfilling the blood-vessels and pre- disposing to catarrhal diseases. In singers the efifect lOO VOCAL AND RESPIRATORY APPARATUS. of nasal stoppage is to render the voice impure or muffled by the congestion of the cords due to the mouth-breathing, and to place undue strain on the voice by trying to overcome the lack of resonance due to the obstructed nose. It is well known to long-distance runners that the breath gives out very soon if mouth-breathing is used, while breathing through the nose is soon fol- lowed by what is called " second wind," during which respiration becomes easy again. Second wind is partly due to a dilatation of the blood-vessels, mak- ing the blood-pressure lower and the heart's action easier. It is also in part due to the fact that in breathing through the comparatively narrow nasal orifice the air enters the thorax with more difficulty than through the mouth; this increases the negative pressure within the chest, causes the respirations to be long and deep, and so gives the thorax an oppor- tunity to pump blood as well as air into its cavity, thus aiding the heart in its work. So deep breathing through the nose during exertion tends to lessen the heart-strain of cycling, running, boxing, or other sports and exercises. The foregoing statements sufficiently prove how indispensable to healthy respiratory organs is an un- obstructed nose. Causes of Nasal Disease. — A healthy nose needs no care by means of sprays, nasal douches, and the like. In fact, the care of the nasal passages involves chiefly a knowledge of the causes predisposing to nasal disease, and as far as possible the avoidance of these causes. There are, however, classes of nasal affections, such as malignant growths, bony tumors, etc., which are not preventable, but much can be TO AVOID CATCHING COLD. 10 1 done to limit the occurrence of the ordinary catarrhal afFections of the nose which lead up to other morbid conditions, such as polypi or suppuration of the air- chambers about the nose called the sinuses. First among the causes of catarrhal nasal afFections is exposure to cold, especially of those portions of the body ordinarily protected by clothing. This occurs especially during high winds or chilly and damp weather, as a result of wetting of the garments, and from insufficient covering at night. It is pro- longed exposure in moderately low temperatures that is dangerous, rather than a short subjection of the body to a sudden cold shock. A cold douche or plunge is followed by vigorous contraction of the smooth muscle-fibers of the skin, driving the blood from the surface, while in prolonged exposure to slight cold there is no such reactiqn of the skin and a a large amount of blood is cooled slowly. This is es- pecially true of those who have made themselves non- resistant and "soft" by excessive clothing or con- tinued indoor life. Contraction of the muscles and vessels of the skin does not take place as readily in such persons as in hardy ones used to exposure and outdoor existence. Cold as a cause of catarrhal nasal affections does not seem operative in very pure air, as is the experience in Arctic exploring expeditions, so that the congestion of the mucous membrane caused by cold appears to need in addition microbic infection to produce the common " colds in the head." To avoid catching cold it is needful to make the body resistant to the influence of cold. The cold shower-bath is of great value for this purpose to those who react promptly. It may be used every morning or evening from from one to two minutes. 102 VOCAL AXD RESPIRATORY APPARATUS. The water should be cold enough to produce a de- cided reaction with the appearance of "goose-flesh" pimples on the skin. As the body- temperature and vigor are lowest in the morning, the evening shower is preferable for delicate people. Over- heated rooms and too much clothing are to be avoided. It is well to see that the sleeping-room does not cool down slowly over night, but that it is properly cooled at bedtime. As is true of most other ailments, the avoidance of nasal catarrh involves also the keeping of the body in its best physical condition, when the nasal pas- sages will resist irritants that in depreciated health they cannot withstand. This is especially so of the inhalation of irritants, such as dust or germs, which of themselves are not likely to cause nasal catarrh in healthy persons. Although the healthy nose can dispose of dust and microbes so well, as soon as its mucous membrane is swollen and inflamed in consequence of catarrhal states it becomes liable to germ infection, so that in the last stages of acute catarrh of the nose, and in many cases of the same affection of a chronic order, we have a purulent secretion on account of pus-pro- ducing germs present in the nose. The bacilli of diphtheria, tuberculosis, influenza and glanders, staphylococci and streptococci, and the contagion of measles and of scarlet fever are all liable to infect the nose, especially when the soil is prepared by a nasal catarrh. It is possible to avoid dust-inhalation up to only a certain limit; but the amount of dust in households should be reduced to at least a minimum. The greatest dust-catcher is carpet, but curtains and THE DRY AIR OF HEATED HOUSES. 1 05 drapery hold large amounts. It is in sweeping and dusting these articles that dust is distributed over the rooms and remains in the air for hours. It is known that the air of rooms contains many more microbes than that of the city streets. Those who have dusty occupations are often told to use a respir- ator, but these contrivances are generally so dis- figuring that few can be induced to wear them, so that in this class there will be many victims of unhealthy respiratory conditions as long as employers do not supply pure air to their establishments. The dry air of heated houses in winter is unfav- orable to healthy conditions in the nose. The se- cretions become scanty, and the mucous membrane becomes dry, preventing the elimination of dust in the normal manner. The mucus forms adherent crusts which are liable to crack and be torn off, in- juring the epithelial coating of .the underlying mem- brane, and so opening the way to germ infection. This is especially the case if a slight catarrhal condi- tion already exists. Erysipelas is sometimes caused in this way, the microbe of this disease entering the fissures and denuded places about the nostrils. It should be regarded almost as important to supply moisture to the air of a house in winter as to supply heat, and until architects appreciate this fact, most persons wall suffer rather than use such troublesome preventive measures as hanging moist cloths in front of the radiators, etc. An atomizer containing a saturated solution of boric acid, with from ^ to i dram of glycerin to the ounce, is a useful article in the care of the nose when the evil conditions — dust-breathing and dry heated air — exist. Its daily employment wdll relieve 104 VOCAL AND RESPIRATORY APPARATUS. the dry irritated condition of the mucous membrane, and act as a preventive of nasal catarrhs by removing the excess of dust. Picking of tiie nose is a very unhygienic habit. Most of the nose-bleeding in children is due to the finger-nail injuries of the mucous membrane of the septum, causing small crusting ulcers. Removal of these crusts is likely to be followed by nose-bleed. The hair-follicles at the nasal entrance are also liable to be infected by the finger, and boils result. All conditions which favor drying of nasal secretions foster the habit of nose-picking in children. A few drops of vaselin brushed into the nostrils of chil- dren will do much to prevent crusting, as all oils dis- solve crusts. Abscess and suppuration of ttie antrum of Highmore, the air-cavity in the upper jaw, is often due to decay of teeth whose roots project into the antrum. Care of the teeth is necessary to prevent this form of disease. THE NASOPHARYNX. The space back of the nose is called the naso- pharynx. Its roof is formed by the base of the skull, its back wall by the vertebrae of the neck, its front by the posterior openings of the nares, its lateral walls by the ends of the Eustachian tubes, which project into the nasopharynx and supply the ear with air. A deep recess, called the fossa of Rosenmiiller, Hes back of the Eustachian orifice and completes the lateral wall. The floor is formed by the soft palate, behind which there is an open space leading into the pharynx. This is closed when the soft palate is made tense and elevated. In children the greater part THE NASOPHARYNX. 105 of the roof of the nasopharynx is covered by what is called the third, or Luschka's tonsil. The evil effects of enlargement of this tissue by adenoid growth have already been referred to as far as stoppage of respiration is concerned, but another important dan- ger of this condition is pressure on the Eustachian tubes interfering with the ventilation of the middle ear — a common cause of deafness in children (see page 157). JlJe«o,d T.SSU6 of Pharytix Vault Fig. 23. — Pharyngeal tube-mouth, as seen by posterior rhinoscopy. Habitual stopping up of the nose in children is therefore always to be taken seriously, as chronic deaf- ness may result from neglect of this condition. The best treatment of enlargement of the third tonsil is its removal by operation. As it is a condition oc- curring in the hardiest and healthiest children, there seems to be no means to avoid its occurrence. En- largement of the third tonsil, unless excessive, usually disappears by atrophy between the twelfth and fourteenth years of life. I06 VOCAL AND RESPIRATORY APPARATUS. The catarrhal states of the nasopharynx are due to the same causes as those of the nose, and their pre- vention requires the measures already described. Catarrhal conditions of the nasopharynx should not be neglected, as they endanger the hearing by the possible involvement of the Bustachain tubes and middle ear. Deafness is also favored by nasal ob- struction, as in such condition the act of swallowing causes a partial vacuum to form in the nasopharynx which sucks the air from the middle ear, drawing in its little chain of bones and stopping their vibratory motions. THE OROPHARYNX. Anatomy and Physiology. — Below the naso- pharynx and continuous with it is the oropharynx, or part of the pharynx connecting with the mouth. It is directly visible through the mouth, while the naso- pharynx is only visible by means of the laryngeal mirror and reflected light. The oropharynx is con- tinuous with the cavity of the mouth, but is separated from it by the isthmus of the fauces, a narrowing caused by muscles which are continuous with the soft palate, and form what are called the anterior and the posterior pillars of the fauces. Between these lie the tonsils, also called faucial tonsils. The posterior wall of the oropharynx is continuous with that of the nasopharynx, and lies in front of the vertebrse of the neck. Its anterior wall is formed by the back of the tongue. The oropharynx is used for both respiration and swallowing. It is a part of the throat that is very resistant to disease, while the tonsils in front of it are, perhaps, more liable to infections than any other part of the body. THE TONGUE \oJ The tonsils are often enlarged as the result of chronic hypertrophy, and are then an obstruction to respira- tion and cause injury to the voice. Many tonsils that do not enlarge are subject to constantly recurring in- flammation, due to repeated microbic invasion. An enlarged tonsil is especially likely to be the seat of diphtheritic infection, making it a constant menace to its possessor. The evil effects of enlarged tonsils on breathing and hearing are not nearly so marked as those of the enlarged pharyngeal tonsil. Neverthe- less, the tonsils are often removed, as they are visible and easy of access, while the worse offender, the third tonsil, is left behind. Children suffering from en- larged tonsils often show a marked gain in weight and health after their removal, and in adults con- tinually recurring infection necessitates treatment and often removal of the tonsils before proper hygiene of the throat can be practised. The deleterious effect of diseased tonsils on general health is becoming universally recognized. In many persons the tonsils are frequently infected with pus- microbes, causing repeated abscesses around them. Many baffling constitutional ailments have been traced to diseased tonsils. The tonsils should always be examined before treating most eye and ear affections. The Tongue. — The back of the tongue is often covered with masses of thickened, decomposmg epi- thelium, which may extend forward to the tip and cause visible "coating of the tongue." It is this epithelium at the back of the tongue which is the cause of most cases of bad breath where there is no actual disease to account for it. Scraping off these masses from the back of the tongue, as far back as one can reach with the ring of one handle of a pair loS VOCAL AND RESPIRA TOR V APPARA TUS. of scissors, removes this bad-smelling material. Most persons do not know that the base of the tongue is often the site from which bad breath arises, and attrib- ute it to catarrh. The cause of coating of the tongue, whether of gastric origin or due to some throat dis- order, is, of course, a subject for medical treatment. The laryngopharynx is the lowest division of the pharynx, and is situated behind the larynx. Below this it becomes the esophagus. It is not much subject to disease of a preventible order, but is a place of frequent lodgement of foreign bodies, fish- bones, and the like. THE LARYNX. The larynx is placed in front of the lowest part of the pharynx, and is composed of a number of carti- lages. The largest of these, the thyroid, forms the greater part of the front of the larynx, and has somewhat the shape of a shield. Below and behind it is the cricoid cartilage, with which the thyroid articulates, being freely movable upon it. The cricoid cartilage has the shape of a signet ring, with the broad part of the ring behind. On the top of this broad por- tion rest two small, very mov- able cartilages, of pyramidal shape, the arytenoid carti- lages. To the front end of these are attached the strong, band-like structures of white, fibrous material, called •' ' iimnn Fig. 24. — Lateral view of lar- ynx in its relation to the hyoid bone and and trachea. THE VOCAL CORDS. 109 the vocal cords, the instruments of sound for the voice. The vocal cords are stretched between the aryte- noid cartilages behind and the thyroid cartilage in front. They are attached in front and laterally to the thyroid cartilage, posteriorly to the arytenoid carti- lages. The larynx has many muscles of small size. Some Image of, epiglottis Image of vocal _ cords Fig. 25. — Schematic view of the tongue-base, epiglottis, arytenoids and ary-epiglottic folds, ventricular bands, and vocal cords, with the laryngo- scopic reflection. of these move the cricoid backward from the thyroid cartilage in such a way that the vocal cords are made tense ; others move the arytenoid cartilages so that they bring the vocal cords together, and others move no VOCAL AND RESPIRATORY APPARATUS. these cartilages apart, so that the space between the vocal cords, or glottis, as it is called, opens for breath- ing. If these last muscles are paralyzed the vocal cords come together and cannot open, so that there is danger of suffocation. There is a muscle seated in the vocal cord that regulates its tension and makes the wonderfully fine adjustments of the voice possible. It is called the musculus vocalis, or thyro-aryte- noideus. For a more detailed description of the laryngeal muscles the reader is referred to works on anatomy. In looking into a larynx with the laryngoscopic mirror (Fig. 25) the most conspicuous structures we see are the vocal cords, two white glistening bands ex- tending forward and back. They stand wide apart at their posterior ends during quiet breathing, leaving a triangular opening, which permits a view down the trachea, or windpipe. When a sound is made the vocal cords can be seen to come too^ether and touch Fig. 26. — The laryngoscopic image in deep inspiration and in phonation. each other with their inner borders. In front of aud above the cords we see the epiglottis, a leaf-shaped structure which curls above the larynx, and is designed to cover it during swallowing of food or liquids. At the posterior ends of the vocal cords we see two FUNCTIONS OF THE LARYNX. Ill roundish bodies, which move out and in with the cords. These are the arytenoid cartilages. Functions of the Larynx. — During inspiration the vocal cords may be seen to move automatically apart, coming slightly together again during expiration. The larynx has, therefore, as its first function that of respiratory opening for the passage of air to the lungs, for which purpose it is needful that the vocal cords should be held apart by the proper muscles. Another function of the larynx is to guard the lower air-passages from the entrance of foreign bodies. Even a small object entering the larynx causes at once a spasm of the vocal cords, that brings them together so tightly that nothing can pass them. This spasm may be lasting enough to cause symptoms of suffocation with blueness of the face ; even death may occur before the spasm relaxes. The most important function of the larynx is the production of voice-sounds. For this purpose three things are necessary : The bellows, supplied by the lungs ; the vibrating membranes, the vocal cords ; and the pipe, or trumpet, beyond them, supplied by the cavities of the nose, pharynx, and mouth. For the production of sound the vocal cords must be brought together and made tense by the laryngeal muscles. The higher the tone of the sound to be produced the more tense are the vocal cords, and the higher the larynx is raised in the pharynx, thus diminishing the length of the pipe, or tube, attached to the larynx, which has been likened to the part of a trumpet beyond the vibrating reed. For low tones the larynx is lowered or descends ; thus the trumpet is lengthened. This raising and lowering of the 112 VOCAL AND RESPIRATORY APPARATUS. larynx facilitates the production of high or low tones, but is not absolutely necessary, for by muscu- lar effort the changes of pitch can be produced with- out change of the position of the larynx. This mus- cular effort, however, is a severe strain for the voice, and it will be referred to under the hygiene of the singing voice. The up and down motions of the lar- ynx can be tested by anyone who feels of the organ during the production of low or high notes. The Production of Voice-Sounds. — While the pitch of the voice is mainly, therefore, furnished by the vocal cords, its timbre, or quality, depends chiefly on the pharyngeal, nasal, and mouth-passages. It is possible to permit the air to pass through the mouth only, when a sound is made, the soft palate shutting off the nose from the mouth ; or the air may be al- lowed to go only through the nose, or through both nose and mouth together. Endless slight modifica- tions of these conditions are possible, so that the vol- untary changes in the quality of the voice by altera- tion of the position of the soft palate, lips, tongue, or pharyngeal muscles are innumerable. So much do the shape, size, and position of the air-passages attached above to the larynx affect the quality of the sound produced that there are no two voices exactly alike, and individuals can be recog- nized by their voices alone. For convenience we will call the oral, pharyngeal, and nasal passages above the larynx the attached tube. If the larynx is detached from this, as it is at times in cases of cut-throat, it makes a feeble sound only. This shows that the attached tube not only gives quality to the voice-sounds, but intensity as CARE OF THE VOICE. II3 well, acting in this way similarly to a speaking- trumpet. The respiratory function of the larynx is interfered with only by actual disease severe enough to so narrow the air-passages as to cause shortness of breath. The Care of the Voice. — A pleasing speech and voice are almost equal to personal appearance in im- portance to the individual in his relations to others. A great number of complex movements are needed to produce proper speech, and these are ac- quired slowly and with difficulty. In fact, a center for these delicate coordinated movements has to be developed in the brain as the child grows. Speech is largely the result of imitation, and if the voices a child hears are harsh or coarse so will its own be- come. The best way therefore to teach a child dis- tinct and refined speech is to let it hear such only. However, this is not always all that is sufficient. Enlarged tonsils and, still more, adenoid vegetations block the way of the sound-waves to the nasal cav- ities after they leave the larynx. This deprives the voice of both intensity and resonance, and compels the child to adjust its laryngeal muscles and those of articulation to the strain thus thrown upon them. This interferes with the acquirement of the delicate coordination of the muscles needed for distinct speech, and such children usually have an imperfect utterance. The number of people that are allowed to grow up handicapped by hasty, slurred, harsh, disagreeable speech and voice is great. Parents do not seem to appreciate the advantage to their children in after- life that a refined, melodious voice will be. Proper singing is one of the best modes of cultivat- 114 VOCAL AND RESPIRATORY APPARATUS. ing a pleasant speaking voice, even if the singer has no chance of anything more than a place in a chorus. It is a delight to hear a good singer speak, and often we can tell that a person is a singer simply from the speech. Improper singing is not only a distress to others, but soon ruins at least the singing voice. Children should be encouraged to sing. It paves the way to singing in adult life, and as they are not self-conscious and not afflicted with improper " methods" they do not strain their laryngeal muscles, especially as the tunes they sing are within easy reach of their voices. This presupposes, of course, that there are no obstructions to the passage of sound- vibrations in the upper air-passages, such as enlarge- ment of either the faucial or the pharyngeal tonsils. Of course, children with hoarseness due to laryngeal ailments cannot sing. Those with an imperfect ear for music may be improved vastly by persistent efforts to sing true. When a child's voice is changing, singing should be prohibited until the adult type of voice has been fully developed. This is true of girls as well as boys. Singing is an excellent form of re- spiratory gymnastics, and tends to develop a full, well- formed chest. In this way it acts as a preventive of lung-diseases. Loss of the adult singing voice means loss of occu- pation to professional singers, and to amateurs the loss of a valued social quality. All singers know what uncertain possessions their voices are. Many voices deteriorate early, or, giving good promise at first, do not stand the training and lose their tone; and this is not without reason. One of the first causes of voice-deterioration is IMPROPER METHOD IN SINGING. II5 imperfect general health. Feeble persons, with weak muscles and imperfect nutrition, cannot develop a good voice, nor can those maintain it whose health has failed. Being non-resistant to disease because of low general vitality, the part put upon the greatest strain, the larynx, is subject to repeated catarrhs and to early fatigue in singing. This strain of the mus- cles of the larynx soon results in loss of the singing voice. A second prolific cause of loss of the singing voice is persistence in singing during attacks of acute laryngitis, a persistence often rewarded with the chronic form of the disease. There is thickening of the mucous membrane, interfering with the action of the laryngeal muscles, hindering approximation of the cords, and causing the muscles to be used too energetically in order to overcome the abnormal re- sistance, so that their delicately fine adjustment be- comes quite disordered. In such cases the singer's notes become untrue in pitch. During attacks of laryngitis the voice should have as nearly perfect rest as possible. Neither should a singer use his voice during an attack of cold in the head, as the abnormal obstruction to the sound-waves caused by the swollen mucous membrane of the nose disturbs the adjust- ment of the laryngeal muscles. The commonest cause of voice-injury is improper method in singing. A singer with proper control of his voice adjusts the vocal cords and the at- tached tube so perfectly by exact muscular action that not only is no power wasted, no muscle made tense that is not necessarily so, but also the proper position is attained at once, so that the moment the Il6 VOCAL AND RESPIRATORY APPARATUS. bellows (lungs) force air through the larynx, the exact pitch and loudness desired are attained and held. In other words, the voice-muscles of a good singer are as perfectly under his control as are the muscles used in keeping the balance of an expert in bicycling. As with other muscles, those of the larynx subjected to excessive action tend to become strong and slow, while delicate adjustments are lost. In other words, they become, as gymnasts say, mus- cle-bound. All improper modes of singing include needless strain of the voice-muscles, and so interfere with their exact adjustment and cause them to con- tract too forcibly, so stiffening their action. One of the worst faults is a rigid position of the larynx, its up and down motion being inhibited, producing a "throat voice." This involves tense contraction of many muscles that should be relaxed, and thus compels them to work under great disad- vantage. One can hardly believe that this imperfect method of singing with suspension of the normal up and down motions of the larynx is a part of a "method" taught by certain vocal instructors. A disagreeable tremolo is one of the bad effects of singing forte under these conditions, and an annoy- ing forced or pressed sound of the voice also re- sults. Another of the evil effects of this strained way of singing is chronic laryngitis with thickening and excrescences of the vocal cords. This is true of any other improper and strained mode of using the voice, though the resistance of the larynx to abuse varies. A voice which is used out of its nor- mal register, especially if there is a constant strain- ing after high notes, is one that will not last long. EXCESSIVE USE OF THE VOICE. ll/ Singing-teachers commit great errors in yielding to the ambitions of pupils, or in not being careful enough in determining the normal voice in question, allowing altos to attempt to be sopranos, and baritones to try to become tenors, etc. Excessive use of the voice threatens its integrity, as do attempts to sing difficult music before the voice has been sufficiently trained. The action of the laryngeal muscles differs from that of many others in that they are continually and with great exactness adjusting the position and tension of the cords, and holding them in certain positions. This renders them especially liable to injuries after prolonged fatiguing contractions. In order to sing well and long, careful practice is needed until little by little the muscles learn their exact adjustments. By im- proper use of the voice it may become irretrievably damaged and even actual disease of the larynx may result. No one should sing until the larynx becomes strained, but an attempt should be made by easy stages to strengthen the voice-muscles until they acquire more endurance. Many persons in speaking or singing are likely to begin the vocal sound sforzando with sudden em- phasis. As this implies bringing the vocal cords together with spasmodic force, such practice not only produces a disagreeable vocal sound, but irri- tates the free borders of the vocal cords, rendering them liable to the occurrence of small prominences, called singers' nodes, which interfere greatly with the clearness of the voice. This spasmodic action of the vocal cords is called the "coup de glotte. " Some strong, robust people with good natural Il8 VOCAL AND RESPIRATORY APPARATUS. voices attempt by sheer muscular effort to overcome their defective vocal education. As these individuals have not learned to co-ordinate their laryngeal mus- cles for proper united action, the result is a dis- agreeable tremolo. Persons with weak physique and imperfect development should strengthen them- selves by calisthenics and breathing-exercises before beginning to sing. Attention to the general nutri- tion of the body is also needed. Those who have lost much weight or have not fully recovered from ex- hausting ailments should not sing. Here it is that the modern method of forced feeding, having the patient limit his daily amount of food not by his ap- petite, but by his digestive powers, is of great value. There is no doubt that a great many of the thin in- dividuals of the community suffer from self-imposed starvation, as their appetites from nervous causes fail and their sense of hunger is lost, while their di- gestive powers are unimpaired. If these were made use of to their limit, they would bring a return of weight and strength. Constricting garments, espe- cially corsets, should not be worn, as they interfere with the chest-expansion, the sustaining of tones, and the regulation of the air-current supplied by the res- piratory muscles. The manner of using the vocal organs in practis- ing singing is, of course, a matter best left to sing- ing-teachers; but as these are not all competent, an attempt has been made to furnish some knowledge as a guide to those who desire to sing, knowledge which it is hoped will help them to tell whether or not they are in good hands when they begin to take singing-lessons. THE CHEST AND LUNGS. 1 19 THE CHEST AND LUNGS. The hygiene of the respiratory organs within the chest includes a consideration of the thorax, the re- spiratory muscles, and the lungs. The thorax, or chest-cavity, is formed by the at- tachments of the ribs, their costal cartilages, and the sternum, to the spinal column. The latter is the fixed base to which the other movable parts of the chest Circufn/erence of apex of thorax. Manubrium sterni Costal cartilages Gladiolus Ensifortn carti- lage of xiphoid appendix Seventh rib Eleventh rib Eleventh rib Circumference of base. Fig. 27. — Thorax, anterior view. are fastened. The part of the spinal column to which the thorax is affixed includes the twelve dorsal vertebrae. Twelve ribs on each side of the body are joined to it, their heads forming joints with the bodies of the vertebrae, while their necks rest on the strong I20 VOCAL AND RESPIRATORY APPARATUS. vertebral transverse processes, moving upon them and being attached to them by another joint at the tip of the transverse process. The ribs end in front in the costal cartilages, which are really elastic prolonga- tions of the ribs. The costal cartilages of the first seven ribs join the breast-bone directly; those of the next three ribs are joined to the costal cartilages above; while those of the last two ribs are unattached and form what are called the floating ribs. The breast-bone, or sternum, closes the thorax m front and moves with the ribs, forming with them a movable cage enclosing the lungs. The muscles of the thorax are the intercostals that fill the space between the ribs and complete the chest- walls; the diaphragm, which closes the cavity of the chest below, separating it from the abdomen; and the auxiliary respiratory muscles, or muscles of forced breathing, which, however, are not in use during quiet breathing. These auxiliary muscles are the scaleni, arising from the neck vertebrae and in- serted into the upper two ribs; the sterno-cleido-mas- toid muscles, arising from the skull and attached to the clavicle; the pectoralis minor, arising from the scapula and inserted into the third and fourth ribs; and the serratus posticus superior muscle, arising from the spinal column and attached to the ribs. The muscles that are used for forced expiration are the abdominal muscles, the serratus posticus inferior, attached to the spine below and reaching up to the ribs, and the quadratus lumborum muscle, which takes its fixed point from the pelvis and pulls the ribs downward. The only muscles in use during quiet breathing are THE LUNGS. 121 the intercostal muscles, the diaphragm, and the leva- tores costarum longus et brevus muscles. These are all muscles of inspiration. Ordinary expiration re- quires no muscular effort at all, as the weight of the thorax and the elasticity of the lungs give sufficient power to contract the thorax and expel the air, the Right common carotid artery Subclavian arteries Innominate artery Arch of aorta' Right lung Superior vena cava Right auricle Pulmonary artery Heart Coronary artery Fig. 28. — Relation of lungs to other thoracic organs. ribs dropping back into the expiratory position after being lifted by the inspiratory muscles. The lungs are composed of an immense number of little air-cells, or alveoli, which connect with the outer air by means of the bronchial tubes. These begin as tubes of microscopic size, which unite to larger and larger ones until they enter the windpipe, or trachea, by means of a large bronchus, or air-tube, for 122 VOCAL AND RESPIRATORY APPARATUS. each lung. The larger bronchial tubes are stiffened with rings of cartilage, and the smaller ones down to a caliber of one millimeter with cartilaginous plates. The smallest bronchial tubes have only circular mus- cle-fibers instead of cartilage. The air-cells, or alve- oli, are coated with thin pavement-epithelium and have the greater part of their walls composed of a dense network of capillary blood-vessels. The function of the air-cells is to allow the red blood- cells to absorb oxygen from the air and give off the carbon dioxid which they hold partly in chemical combination and which is partly also contained in the fluid blood. The lung is therefore a gland designed to take in and excrete the gaseous constituents of the blood. The red blood-cells do not simply absorb the oxygen of the air, but take it into loose chemical combination with their pigment of hemoglobin. This in turn delivers the oxygen to the tissues of the body. The blood passing through the capillaries of the air-cells comes from the pul- monary artery and right ventricle of the heart, and is venous blood while in this vessel. It leaves the capil- laries lining the air-cells to enter the pulmonary veins as arterial blood, or blood which has taken up oxygen. The lungs have a further blood-supply for their own nutrition, as that which passes through the capillaries of the pulmonary artery is not utilized by the lung itself, but is utilized merely for the pur- pose of oxidation. The arteries supplying the lungs with nutrient blood are called the bronchial arteries, and are branches of the aorta. The walls of the alveoli of the bronchial tubes and of the interstitial tissue between the lobules, or THE MECHANISM OF RESPIRATION. 1 23 clusters of air-cells, at the end of a bronchiole, or minute bronchus, are all composed largely of what are called elastic fibers. This gives to the lung its rubber-like power of elastic retraction after expansion. The lungs are not attached directly to the chest- wall, but are covered by a smooth glistening mem- brane called the pleura. A similar membrane lines the inside of the chest-wall, and though the lungs lie in contact with this wall they are not attached to it, as the layer of the pleura covering the lung, while in touch with that lining the chest-wall, nevertheless glides smoothly upon it during the respiratory motions. If the chest-wall is perforated, the lung collapses by reason of its own elastic retractility, air meanwhile rushing into what is called the pleural cavity between the two layers of the pleura. In health, of course, there is no cavity, as these layers lie against each other. The lungs are kept expanded by the suction of the chest-wall, and in health never entirely collapse. The inspiratory muscles lift the ribs upward and outward, thus increasing the capacity of the chest in its circumference, while the diaphragm descends, increasing the capacity vertically. This causes an increase of the negative pressure in the chest; and as in health air cannot enter the pleural cavity, the lung must follow the pulling force of the expanding thorax and fill with the air that rushes into the trachea. Ordinary expiration takes place, as stated, by means of the retractile power of the lung and the weight of the chest-walls, no muscular effort being needed. It is obvious that when expanding the lung must not only suck in air into its air-cells, but also must draw blood into its capillary vessels. The narrower 124 VOCAL AND RESPIRATORY APPARATUS. the orifice through which the air passes the more power is left to suck in blood, so that nose-breathing is an aid to the circulation of blood in the lung, while mouth-breathing is not. The thorax loses mobility and expanding power in later life, and in the aged becomes stiff and rigid. The motion of the ribs in their sockets becomes limited, while the elastic costal cartilages, which are twisted or undergo torsion during each inspiration, normally become too stiff to yield in this way to the inspiratory pull. Age therefore dis- qualifies for violent exertion, as this rigidity of the thorax gives the respiratory muscles more work to do, and breathlessness comes sooner during exertion in age than in youth. By continuing gymnastics and respiratory exercises through life the greater part of the mobility of the thorax can be maintained till a very advanced age. This is an argument against the theory that after youth is passed, gymnastics are of no use. Deformities of tine Thorax. — The highest efii- ciency of the lungs as organs of blood-oxygenation demands a well-formed thorax; yet it is precisely the thorax that of all parts of the skeleton is most often deformed, a fact which accounts in part for the fre- quency of lung-diseases. The chest is simply an air-pump, and if its capacity is diminished by being bent out of shape it can obvi- ously suck in less air than is necessary. This is also the case if its movements are restricted. In the extreme chest-deformity of hunchbacl may prove real helps. Of a dozen of the same make, one or two trumpets may be far better than the rest; and the deaf person should obtain advice as to the kind of instrument to test and then try a number of that form. Such aids are not only of temporary benefit, but when rightly used they may permanently improve the hearing. Electric telephone-like instruments are often valu- able, transposing unheard low tones to the higher pitch, where they are better, perhaps normally, heard. Yet the energy of vibration is small, its massage-value far less than that of the unaided voice intelligently used, and much use of any telephone may be danger- ously fatiguing. THE HYGIENE OF THE EYR By WALTER L. PYLE, M. D., OF PHILADELPHIA, Assistant Surgeon to Wills Eye Hospital. GENERAL DESCRIPTION OF THE EYEBALL AND ITS DISEASES. Advantages of Binocular Vision. — Fortunately man is endowed with two eyeballs. Such a delicate organ as the eye is very susceptible to destruction of function from injury and disease, and in case one eye is ruined its fellow can in great part compensate for the loss. The additional advantages of binocular vision are many. There is a more accurate estima- tion of size, depth, distance, direction, and motion, all of which are matters of gradual education from infancy and have psychologic and physiologic expla- nations which are not within the province of this article. Binocular vision also affords a much better field. A person with one eye is handicapped by the limitations of vision caused by the protrusion of the nose obscuring objects on the side of the blind eye. The eyeball resembles in shape a sphere or globe; on the anterior surface of which is placed the segment of a smaller sphere (Fig. 35). The average diameter of the eyeball is approximately one inch. It is a trifle longer anteroposteriorly than vertically. It is contained in a conical cavity formed by the bones 171 172 THE EYE. of the face and skull, called the orbit (Fig. 36), and is supported by a cushion of fat and other tissues. It Sclera. Choroid Ciliary muscle. Iris, Conjunc. cul-de-sac Ant. chamber and aqueous humor Crystalline lens Posterior chambe Angle o/ant. chambe Suspensory ligaittettt^ of the lens Ocular muscle Retina Optic ^ — nerve -with ~" central retinal 'i==2\^ artery Ocular muscle Cornea Vitreous chamber Fig. 35. — Vertical section through the eyeball and eyelids. is held in place by its membranes and muscles, by which it is also moved; and it is surrounded optic foramen. Fig. 36. — The bony orbit, showing the optic foramen. by a thin membranous sac, called the capsule of Tenon. Hence, laterally and posteriorly the eye- THE EYEBROWS. 1 73 ball is well protected by the bony orbit, and is shielded against shock by the orbital tissue and fat. So important is the function of the fat of the orbit that it is said to be the last to disappear in emacia- tion from disease or starvation. The anatomic conformation of the skull varies greatly indifferent individuals and race; and accord- ing as the orbit is deeply set with overhanging ridges of the frontal bone, or is more exposed, there is a dif- ferent amount of bony protection afforded the eyeball. Some eyes are very deep set in the skull, while others are quite protruding and more liable to injury. Ante- riorly the eyeball is protected by the eyebrows, eye- lids, and eyelashes. The eyebrows are formed of muscle, thickened skin, and stiff hairs, which rest over a bony ridge in the front of the skull above the margin of the orbit. They are not seen in the lower animals. The func- tions of the eyebrows are to protect the eye from dust and perspiration, and to give shade to the eye. The eyebrows have a marked influence on facial expres- sion, and many shades of emotion are portrayed by their movements. In some persons the eyebrows are very scant, in fact in fair women they are some- times only delicately pencilled, while in others, for instance swarthy men, they are long, thick, and bushy, giving a most ferocious appearance, especially when unkempt. There is a tendency for the hair of the eyebrows to become thickened and tough in ad- vancing age. Burns of the eyebrow require the same treatment as skin-burns, and unless the damage has been very severe the hairs will reappear. Drop- ping out of the hairs of the eyebrows and other 74 THE EYE. defects may be treated in the same manner as hair- defects elsewhere. The eyelids are composed of thin, loose skin, elastic tissue, delicate muscle, and plates of carti- lage, called the tarsal cartilages, which give the lids shape and firmness. The upper lid is the larger and is movable, while the lower lid is almost stationary. There is no fat in the eyelids, and if this were not the case, in extreme obesity they would become closed by their weight. However, the loose tissue of the lids affords an ideal field for swelling, and after blows or in inflammatory conditions, such as erysipelas, we find the lids sometimes so swollen as to be entirely closed. The ordinary " black eye " is simply extravasation of blood into the loose tissues of the lid, from which it is some little time in being absorbed. In recent injury or disease of the lids, cold in the form of iced compresses is indicated to prevent further exudation, while in the later stages hot compresses are necessary to promote absorption of the exudation or hemorrhage which has already taken place. There is no virtue in a poultice beyond the continued heat, and local medicinal measures are of little value. For cos- metic purposes a bruised lid may be painted flesh color. The delicate construction of the eyelid enables the physician to judge well of the general circulation from its appearance. A dark hue of the skin of the lids, the so-called "rings around the eyes," is indica- tive of a sluggish circulation or of changes in the composition of the blood. Pufiiness or swelling of the lids, popularly known as " bags under the eyes," THE EYELIDS. 1 75 is often an early sign of disease of the heart or kidney. The lids are lined with a very smooth membrane, called the conjunctiva, which will be spoken of later. They are maintained in close apposition to the eyeball by atmospheric pressure. They move freely and without friction on account of the smoothness of their inner surfaces and the outer surface of the eye- ball, and the lubrication by the tears and the mucus secreted by the conjunctiva. On the edges of the lids, near the roots of the lashes, are the small Mei- bomian glands, which secrete an oily substance greasing the lid-borders and helping to prevent the overflow of tears. An important function of the lids is to distribute the tears over the front of the eyeball, and by inces- sant winking to free the front of the eye from dust and keep it moist. The winking also acts as a hydraulic pump in discharging the excess of tears through the tear-duct into the nose, besides affording frequent intervals of rest for the retina. When the eyelids are paralyzed or when on account of protru- sion of the eyeball they cannot be closed, the front of the eyeball, or cornea, quickly loses its lustre and transparency, and unless this is speedily remedied blindness will ensue. The protective function of the eyelids is very evi- dent, and is so automatic that the lids close reflexly at the approach of a foreign body or a threatened blow. The opening between the lids is called the com- missure, and on the width and breadth of this de- pends the size of the eye. When one speaks of a 1/6 THE EYE. large eye or a small eye, reference is made to the size of the palpebral commissure and not to the size of the eyeball. There is no noticeable difference in the actual size of healthy eyeballs, except, of course, as belongs to the different ages, the child having a smaller eyeball than the adult. However, in some persons the size of the pupil gives to the eye an addi- tional element of size. The racial characteristics are transmitted in the size and shape of the commissure, as is shown in the almond eye of the Mongolian. The shape of the commissure has a marked influence upon the expression and upon the personal beauty. Actresses avail themselves of dextrous pencilling to prolong the shadow of the commissure and produce impression of large eyes. A villainous expression is made by pencilling the outer angles of the commis- sure upward. A drooping and partially closed lid gives the impression of languor, and it is also used by artists to portray fatigue and voluptuous passion. In the final stages of wasting diseases the half-closed eye is a sign of impending physical dissolution. The eyelashes, or cilia, are given off from the lid- border, and differ from the hair elsewhere by their finer texture and in being thicker in the middle than at the ends. They are arranged in two curves, those of the upper lid having their convexity downward while those of the lower lid have their convexity upward. Thus when the lids are partially closed, the eyelashes interlace, forming a screen against wind, dust, or excessive light, while still allowing the en- trance of light and vision. They are supplied with sensitive nerves at their roots which serve to warn against the approach of small bodies when in the THE EYELASHES, OR CILIA. 1 77 dark, or when the vision is intently employed elsewhere. The lashes are constantly being renewed but the falling out should not be noticeable. In certain inflammatory conditions of the lid- border, known as blepharitis, the eyelashes may so fall out as to become very sparse. If the inflamma- tion is allowed to go untreated, there is often formed a permanent " blear eye ; " the new lashes come in stiff and are often misdirected, turning in toward the eyeball instead of outward. These wandering lashes are popularly known as " wild hairs," and cause great discomfort by constantly rubbing against the sensitive cornea. Such errant cilia must be con- stantly pulled out, or their bulbs must be destroyed by electricity, and in some cases even a plastic oper- ation on the lids is necessary for relief. Inflammation of the lid-edges with destruction and distortion of the lashes is a most unsightly facial blemish, and if not properly treated will grow pro- gressively worse. In a great number of cases it is one of the many results of ocular congestion from un- corrected eye-strain, and will only be relieved by the wearing of the proper glasses. Salves and ointments may alleviate, but will never cure such cases. In other instances blepharitis is a local expression of a general disease showing elsewhere in the skin, and will only yield to general medicinal and dietetic treatment in the hands of a competent physician. An exceptional cause is the presence of tiny insects, nits, pediculosis (lice), or scabies (itch), at the roots of the lashes. In some cases the vitality of the lashes is lowered in common with that of the hair elsewhere. In such cases a stimulating or irritant treatment is indicated. 12 178 THE EYE. The lacrimal or tear apparatus (Fig. ^"f) consists of a lacrimal gland which secretes the tears. It is situated at the upper and outer angle of the orbit, and is connected to the conjunctival cul-de-sac be- tween the eyelids and the eyeball by eight to twelve Lacrimal glatid Canaliculus Fig. 37. — Diagram of the lacrimal apparatus. small ducts which open by a series of pores about ^ of an inch apart, at a little beyond the border of the upper lid. The tears are discharged from the gland into the conjunctival sac and flow across the front of the eyeball toward the inner corner of the eyelids, where they are received in a small opening in both upper and lower lid-borders, called the punctum. From here they flow through two minute canals, called the lacrimal canaliculi, to the lacrimal sac, or "tear-bag," lodged in a groove in the lacrimal bone below the inner angle of the lid-commissure, or internal canthus. When distended, this sac forms a protrusion at the inner angle of the lids and may be compressed through the lower lid, expelling its con- tents through the punctum into the conjunctival cul- de-sac or into the nose. From the lacrimal sac the CONSTANT EXCESSIVE LACRIMATION 1 79 tears are directed through a bony canal, Y^ inch long, called the nasal duct, into the nose. The forces at work in the passages of the tears from the gland to the nose are capillary attraction, as furnished in the canals, gravity causing them to fall over the conjunctiva and through the canals, and muscular movement of the lids in winking. In the act of winking the tear-sac is expanded by traction of the muscles, and the tears are sucked into it; then passive contraction of the tense elastic sac expels the tears on through the nasal duct into the nose. Ordinarily there is such a perfect balance between the secretion and excretion of tears that by no sub- jective sign are we conscious of them. When, how- ever, from emotion or by irritation from the wind, dust, pungent vapors, or intense light there is an ex- cessive secretion of the tears they may overflow the lids and roll down the face as well as be felt in the nose. In crying or on a windy day there is usually an accompanying "sniffling" or "blowing of the nose," due to an increased amount of tears draining into the nasal chambers. Infants do not shed tears until after the third month. Constant excessive lacrimation with overflow on the cheek, or epiphora, commonly called "tearing" or " watering of the eyes," may be due to: i. Living in vapors or dust or chemicals, as millers, metal- grinders, excessive smokers, etc. ; 2. Inflammation of the lid-membrane (conjunctivitis); 3. Bye-strain, either from excessive reading or working in bad light or from defective eyes. If a careful inquiry into the patient's habits and an examination of his inner lid- surfaces reveal no cause for the tearing, examination l80 THE EYE. of the eyes under complete cycloplegia is advisable. Wlieu the tear-sac is distended and inflamed (dacryo- cystitis) very serious disturbance may result if the cause is not properly treated by a physician. The conjunctiva is the thin, transparent mucous membrane that lines the front of the eyeball and is reflected to the inner surfaces of the eyelids, forming, when the lids are shut, a closed sac. Except over the cornea, the conjunctiva is quite vascular, and on ac- count of its many small blood-vessels it is quite likely to become congested from irritation, injury, or dis- ease, causing what is popularly known as " pink eye " or "red eye." As an example, note the quickness of the eye to become red from the irritation of excessive tear-supply in weeping or following the irritating vapor of tobacco-smoke, or lodgement of a small foreign body. The conjunctiva is continuous with the mucous membrane of the nose and mouth. Hence in in- flammation of the nasal mucous membrane, as in an ordinary ''cold in the head" or in influenza, the conjunctiva is quite likely to become much congested. In fact, in such cases people speak of "catching cold in the eyes." Again, in inflammation of the alimen- tary tract in chronic alcoholism or after a debauch it is common to see the "blood-shot eye." True inflammation of the conjunctiva is called conjunctivitis. Ordinary catarrhal conjunctivitis, or "red eyes," is most commonly due to eye-strain, and until excessive eye-work is forbidden and the proper correcting lenses are ordered the conjunctivitis will continue to occur. Students who use their eyes excessively and often by poor light, firemen, ''GRANULAR LiDSr l8l puddlers, and others who are exposed to great glares or dazzHng lights are subject to conjunctivitis. Other causes are chronic nasal catarrh, diseases of the tear-apparatus, working in irritating vapors, ex- cessive smoking, particularly in a sitting position in- doors, where clouds of smoke are constantly wreathed about the head and face. Chronic conjunctivitis may also be caused by the habitual use oij ace-powder, espe- cially if dusted on the face by means of a powder-puff , The roughened membrane gives rise to a continual sense of foreign body in the eye, which causes the patient to rub and further irritate the membrane. The burning and smarting are sometimes intolerable. A pleasant eye lotion in such cases is a 2 per cent, solution of boric acid in water. Purulent conjunctivitis is fortunately a rare dis- ease, as it speedily may become most fatal to the eye, causing the clear cornea to ulcerate, often destroying not only the sight, but also the whole eye. It is puru- lent conjunctivitis of new-born infants that is such a prolific cause of blindness. Immediately upon the appearance of red eyes in the first few days of life a physician should be summoned. A few hours' delay with home treatment may mean blindness for the child. The greatest care should be taken to prevent contagion in any household in which there is a puru- lent conjunctivitis. All towels, cloths, compresses, etc., used on the patient should be destroyed, and the soap and basins used should be kept separate, and if only one eye is infected every precaution should be taken to shield its fellow. One patient with purulent conjunctivitis has infected a whole family, several of the cases resulting most disastrously. " Granular lids " is a name often given to ordinary 1 82 THE EYE. chronic conjunctivitis by the laity. True granular lids, or trachoma, is a much more" serious affection and is particularly obstinate. The inner conjunc- tival surface of the lids becomes roughened and by constantly irritating the cornea impairs its transpar- ency. The inflammation also gives rise to distressing distortion of the lid-borders by the formation of con- tracting scar-tissue, which causes misdirection of the eyelashes, so that they turn in against the globe, a condition known as entropion. This disease is most common among the poorer classes, and particularly where many are huddled together in one dwelling and where dwellings are closely built. It is often al- most epidemic in barracks and charitable institutions. When once an inmate of an almshouse, asylum, or school has been attacked by a severe case of con- junctivitis of any kind, he should be immediately reported to the physician and forbidden to use the public towels, soap, or wash-troughs, and should as far as possible be isolated from his fellows until his disease is cured. In the same way applicants for ad- mission to large institutions or conscripts should have their eyes scrupulously examined, even to ever- sion of the upper lid, to be sure that there is no trachomatous disease present. There is nearly always affection of the conjunctiva in measles — in fact, the " measly eye " is well known. Certain other infectious diseases, such as scarlet fever, small-pox, and diphtheria, may seriously affect the conjunctiva and cornea, even causing blindness. The nurse and medical attendant in their anxiety to pre- serve life should not neglect the necessary precautions to protect the eyes from serious invasion. Subconjunctival hemorrhages are usually the SUBCONJUNCTIVAL HEMORRHAGES. 1 83 result of a blow or other injury, but they sometimes occur spontaneously, and often in the night while asleep. While not always true, it may be said that this is indicative of brittle or degenerated blood- vessels, and that unless precautions are taken a cere- bral apoplexy may follow. Hemorrhages of the conjuctiva sometimes occur in violent coughing or in straining at stool. Many persons suffering more or less continuously from inflamed eyes are in the habit of treating them- selves and paying no regard to the cause of the dis- ease. They resort to the quack " eye- waters " or "eye-drops," many of which contain powerful drugs, such as cocain and atropin, the constant use of which only further augments the trouble. A question often asked is, whether hot or cold water is better for the eyes, and even persons with healthy eyes continually bathe their eyes "to make them strong." In perfectly healthy eyes it is always unnecessary to use continuously any eye-wash or to open the eyes under water. The conjunctiva of man differs from that of a fish, and any prolonged expos- ure to water will surely cause irritation. In acute inflammations the application of cold water is sooth- ing and retards inflammation; after the inflammation is well under way, continued applications of very hot water may help in constricting the blood-vessels, re- ducing swelling, and relieving pain. However, in cases of chronic conjunctivitis the patient is usually suffering from some unknown exciting cause contin- ually operative, most likely eye-strain; and instead of attempting to treat himself or indifferently allow- ing the disease to progress, he should consult an ocu- 184 THE EYE. list as to the advisability of wearing glasses or other treatment. If the habit of using eye-washes is firmly established, a very pleasant and harmless lotion is made by dissolving 40 grains of boric acid in 4 ounces of distilled water, rose-water, or camphor- water, and afterward filtering. The proper way to use an eye-lotion is as fol- lows: The patient should throw the head far back or recline in a chair or on a couch and look upward. The lower lid is gently pulled downward, and with a clean glass pipette or eye-dropper several drops of the solution are placed quickly but gently in the corner of the eye. The lids should not be violently closed, as in such case the liquid is all squeezed out on the cheek; but the eyeballs should be slowly rotated, diffusing the fluid over all parts of the conjunctival cul-de-sac. The lotion should be allowed to dry in the eye, and should not be wiped out with a handker- chief The pipette should be cleansed before being used again. It is well to keep the lotion in a bottle with a sufficiently small neck to allow the glass pipette to act as a stopper in place of the ordinary cork. The use of eye-cups is not recommended. Growths of the Conjunctiva. — Often fatty deposits in the conjunctiva cause needless alarm. A Pinguecula is a small, yellowish growth on the conjunctiva over the eyeball, which, although often progressively in- creasing, never causes discomfort or needs treatment. A pterygium is a fleshy growth on the conjunctiva with the base toward either canthus and apex toward the pupil. This growth is common in old people, and especially in those who have been exposed for years in outdoor occupations, as, for instance, in sail- THE CORNEA. 1 85 ors. It is not malignant, and if it enlarges so much as to interfere with the motion of the eyeball or to obscure vision it may be easily removed. The cornea may be called the window of the eye. It is a transparent smooth tunic enclosing the anterior fifth of the eyeball. It is circular, and by the way it is fitted into the sclera it resembles a watch-crystal. It is without blood-vessels, but is supplied with an abundance of nerves, making it very sensitive. Dis- ease of the cornea is very disastrous to vision, especi- ally when the central portion over the pupil is affected, as it is quite likely to leave white scars which greatly interfere with vision. Unless formed in early child- hood, these opacities are not likely to clear up. Dis- eases of the cornea are also very painful on account of the abundant nerve-supply, and the pain caused by exposure to light is great. Corneal disease occurs particularly in persons who are run down in health, and in sickly or congenitally diseased children, who also show signs of ill-health elsewhere, such as bad teeth, nasal catarrh, etc. In such cases a rigorous tonic and dietetic treatment is as necessary as local measures. Fortunately, the cornea is very tough and resistant, as it is the part of the eye most exposed. It is washed with tears continually to clear it of small particles of dust and keep it polished and transparent. It is fre- quently the seat of injury, and affords a common loca- tion for lodgement of foreign bodies. It is not uncommon, among persons who have not made a careful study of the eye, for white scars on the cornea resulting from injury or disease to be mistaken for cataract. Old corneal opacity cannot 1 86 THE EYE. be removed, and is a prominent cause of incurable blindness; in fact, in former years the greater num- ber of inmates of blind asylums owed their trouble to opacity of the cornea following either ' ' sore eyes of the new-born" (ophthalmia neonatorum) or small- pox. Arcus senilis is a circular opacity at the periphery of the cornea, seen generally in aged persons. It is sometimes mistaken for beginning cataract. It is the result of a senile, degenerative process, and is not dangerous to the eyeball, and never interferes with vision, as it is so far removed from the center of the cornea. The sclera is the external tunic of four-fifths of the eyeball. It is continuous with the cornea in front. It is an opaque, tough fibrous membrane, and forms the chief support of the eyeball. By reason of the white appearance of its anterior surface it is com- monly called the "white of the eye" (Fig. 38). upper lid-border Iris 7vith corneal reflex anterior Sclera Lower lid-border Fig. 38. — The anterior surface of the eyeball. The iris (Fig. 38) is a circular contractile mem- brane made up of elastic and muscular tissue, blood- vessels, and nerves suspended from the edges of the cornea in the front of the eye like a curtain. The THE IRIS. 187 iris gives the color to the eye ; and when we say that an eye is blue or brown we mean that this is the color of the iris. This color of the iris is derived in part from a purplish pigment, and is due in part to certain optical phenomena of reflection of light from uneven surfaces. The iris is freely movable, and according to whether it dilates or contracts we have an alteration in the size of its central aperture, called the pupil. The color of the iris at birth is blue, which, how- ever, changes in the first few weeks to the permanent color. In albinos there is an absence of pigment in the iris as well as in the hair and skin, allowing the red reflex from the blood-vessels in the choroid to shine through, giving the eyes a pinkish hue. As a particular function of the pigment of the iris is to prevent transmission of light-rays through its sub- stance to prevent dazzling, in albinos there is great distress on exposure to light. There is a popular superstition that certain colored eyes are stronger than others. There is nothing in this belief other than that a dark-colored iris is perhaps better fitted to protect the retina from intense sun-glare, and hence is found more among the tropical nations, while light- colored eyes are more general among the northern races. In our climate bluish or grayish e3^es may be as serviceable as those of darker color. The chief function of the iris is by contracting and dilating to regulate the amount of light admitted to the interior of the eye. This has a protective as well as an optical purpose. In the presence of a strong light the pupil quickly contracts, shutting out exces- sive light ; while in subdued light or semi-darkness it dilates, allowing more light to enter. When looking l88 THE EYE. at a distance or when looking languidly into space the pupils dilate. Artists take advantage of this fact, and in portraying pensiveness or reverie paint large pupils in the eyes. In using the eye at close range the accommodation is brought into play in a manner described later (page 210), and the pupil is also con- tracted, allowing more distinct vision. The optical principle herein may be easily demonstrated by any- one with defective vision who will look through a pin-hole in a disk or card. They will see almost as distinctly as with their glasses, although, of course, they do not have as great a field of vision. Any interference with the movements of the pupil indicates either inflammatory synechise or serious brain- or nerve-disease. However, the pupil may be- come dilated and inactive after the use of certain drugs called mydriatics. Among these are belladonna and its alkaloid atropin, cocain, and homatropin. Miotics are drugs which contract the pupil. Among these are calabar bean and its alkaloid eserin, pilocarpin, and opium. One of the prominent symptoms of profound opium-poisoning is pin-point contraction of the pupil, which dilates just before death. The Size of tiie Pupils. — In health the pupils are of equal size and react to light synchronously, but there is great difference in the normal size in different persons. Late in life the pupil grows gradually smaller, in a measure compensating for the ocular defects incident to age. Marked inequality in the size of the pupil is generally, though not always, in- dicative of serious brain- or nerve-disease. Large pupils are generally and properly considered a sign of beauty, and it is sometimes the practice THE OPHTHALMOSCOPE. 189 among actresses, singers, and other women who ap- pear in public to produce an artificial dilatation by the use of a weak mydriatic solution. A large pupil in- dicates a particularly active sympathetic system, and pel ions with large pupils are more subject to asthe- nopia from astigmatism or other refractive defects. It is in such people that insignificant correcting lenses produce the most marked beneficial effects. Strong emotions and passions cause dilatation of the pupil. The typical picture of fright is a dilated pupil with widely parted eyelids. Ordinarily the pupil appears black. Rays of light entering the eye through a pupil are reflected back in the same direction in which they enter ; and as our Fig. 39. — Ophthalmoscope. own eye is not the source of light or in line with the source of light the pupil appears black. When, how- ever, the observer's eye is artificially made the source of light, and if he looks in the same direction as that 190 THE EYE. in which the luminous rays enter the observed eye. as, for instance, through the central sight-hole of a reflecting mirror (Fig. 39), illumination renders the interior of the eye visible. This is the fundamental principle of the ophthalmoscope; and the simplest form of ophthahnoscope is a mirror in the center of Fig. 40. — The normal eye-ground as seen with the ophthalmoscope: «, optic nerve-head; m, macula; a, retinal artery; v, retinal vein. which is scraped an opening in the silvered back, through which the observer looks at the eye under observation. By directing the reflection of a lamp- or gas-flame into the observed eye and looking through the sight-hole in the mirror there is seen the red re- flex of the choroid in the pupillary space, and by com- ing closer to the pupil there may be seen the blood- IRITIS. 191 vessels of the retina and the shining white head of the optic nerve (Fig. 40). This is better accomplished by darkening the room and placing the source of light back of the subject's head, as the pupil then becomes dilated and the contrast is greater. By subdued light the pupils of certain animals pre- sent a bright glare. This is particularly noticeable in the domestic cat, and is due to reflection from a modified choroid, called the tapetum lucidum, a bril- liant greenish reflecting membrane between the retina and sclera. Inflammation of the iris is called iritis, and is a very painful and dangerous disease, sometimes caus- ing blindness. At the onset it resembles conjuncti- vitis, and is often attributed to " catching cold in the eye." The patient should not attempt to treat it by home remedies or common eye-lotions, until the dis- ease has been allowed to progress so far as to bind the iris down to the lens-capsule. In such cases a few drops of atropin solution applied under the guidance of a skilled oculist would render this accident impos- sible. The ciliary body is situated at the junction of the iris and choroid, and is quite susceptible to diseases affecting either membrane. It is composed of sixty or seventy folds formed by reduplications of the choroid at its anterior margin, called the ciliary proc- esses, and a grayish transparent band of muscular tissue about one-eighth inch broad, called the ciliary muscle. This consists of radiating and circular fibers, the former arising from the junction of the cornea and sclera, passing backward to the choroid opposite the ciliary processes ; the latter are internal, i92 THE EYE. and pursue a circular course around the insertion of the iris. This little muscle is an important factor in accommodation and eye-strain, and is spoken of at length later (see page 212). The choi-oid is the vascular and pigmentary tunic of the eyeball investing the posterior five-sixths of the globe, extending as far forward as the cornea and developing ciliary processes from its inner surface anteriorly. It lies between the sclera externally and the retina internally. Its function is to supply blood to the interior of the eye and to absorb superfluous liofht. Inflammation of the choroid is called cho- roiditis, and is generally the result of systemic disease, particularly of the type accompanied by disease of the blood-vessels. Other causes are injury, infection, high myopia, retinitis, and iridocyclitis. Disease of the choroid is particularly disastrous to vision on account of involvement of the contiguous mem- brane, the retina, and the continuous structures, the ciliary body and iris. The retina is the innermost of the three coats of the eyeball, and is the chief peripheral portion of the visual apparatus. It is made up of the percipient end-organs and expansion of the fibers of the optic nerve in the eyeball. It is composed of three main layers: the inner, of fibers and nerve-cells; the granu- lar middle layer; and an internal layer, composed of rods and cones and pigment. The rods and cones are the essential sight-elements. The light entering the eyeball through the pupil impinging on the cones is received and transmitted through the other layers to the optic nerve, and thence on to the visual centers THE RETINA. 1 93 in the brain. The retina is freely supplied with blood- vessels. The most sensitive part of the retina is the macula lutea, or central spot, which covers an area of about one- fiftieth of an inch in diameter, to the temporal side of the entrance of the optic nerve. In the very center of this part of the retina is the fovea centralis, in which all the layers are missing but the essential cones. So important is this minute portion of the membrane that if it is encroached upon and destroyed by dis- ease, useful vision is lost, although the peripheral part of the retina may be intact. In such a case, if the patient looked directly at an object he could not see it, although he would have an indistinct view of the objects at either side of it. It can be readily understood how helpless in reading or working at close range such a person would be. On the other hand, considerable areas of the surrounding retina may be destroyed and yet useful vision be pre- served, provided the macular region is intact, the extent of side vision only being limited. However, defects in the retina may cause blind spots in the j&eld of vision, called scotomas. There is a natural blind spot at the entrance of the optic nerve. This may be demonstrated by experiments with the cross and circle described on page 195. The retina has often been compared to the sensitive plate of a camera, and from this comparison have arisen such absurd statements as the finding of a photograph of a murderer in his victim's eye. The retinal images are not permanent, as witnessed by the numerous and rapid succession in which they change. However, even this rapidity has a limit. If we take 13 194 THE EYE. a firebrand and twirl it around rapidly in front of the eyes, it is impossible for the eye to perceive the images of the fire in each position of its revolution; and instead of several pictures of the burning brand we see only a circle of fire. That retinal images have some permanency of duration, however, is proved by looking intently at a luminous object for some time and then turning the gaze against a black wall or ceiling for a moment, when there will be seen the image of the object still before the eyes against the new surface. No one has ever discovered a retinal image, and to see it in the eye of a human being as described in sensational newspaper reports the ob- server would have to use an ophthalmoscope, other- wise these retinal images would be invisible. To be seen with the naked eye, the image must be located on the cornea or iris, and for an image to be placed here would require the interposition and accurate ad- justment of a convex lens between the face of the assailant and the eye of the victim — a most preposter- ous supposition. The optic nerve connects the retina with the brain. Its sole function is to carry sensations of light. It does not convey the sensation of pain. Disease or injury to the retina and optic nerve may occur to such an extent as to cause blindness with- out the victim ever suffering the slightest local pain. When suddenly shocked, the optic nerve, instead of giving a sensation of pain, gives rise to indefinite sensations of light, such as are commonly known as "seeing flashes'^ or '^ stars." Unlike the retina, the optic nerve cannot receive impressions of light any more than a telegraph wire can receive and THE OPTIC NERVE. 1 95 interpret a message. They are both only means of conveyance of impressions. In fact, at the point in the eye-gronnd where the optic nerve enters there is a normal blind spot which, projected into the field of vision, constitntes the well-known " Mariotte's blind spot." This may be readily demonstrated by directing the right eye accurately to the cross in Fig. 41. Closing the left eye and withdrawing the page Fig. 41. — Diagram to demonstrate the " bli-d spot." to about ten inches from the eye the circle will entirely disappear, for at this point the image of the circle falls directly on the unresponsive optic nerve-head. Serious disease of the optic nerve, by interrupt- ing the means of communication between the retina and brain, produces blindness. It is generally the result of systemic disease, but may be due to the excessive use of alcohol, tobacco, or other noxious substance. Complete atrophy of the optic nerve is an incurable disease, and when total there is not even perception of light left, and sometimes contrast between bright light and darkness is lost. The humors making up the bulk of the eyeball are called the aqueous and the vitreous. They are both perfectly transparent for the free transmission of light The aqueous humor occupies that part of the 196 THE EYE. eyeball in front of the crystalline lens and is a slightly alkaline watery fluid. The vitreous humor occupies the large part of the eyeball lying behind the crystal- line lens and is a jelly-like substance. Disease of the various membranes of the eyeball may disturb the transparency of the humors, causing either diffuse clouding and blindness, or only single floating opaci- ties showing as dark spots before the eyes. These are, however, quite visible to the physician by the ophthalmoscope, and must not be confounded with the microscopic opacities known as muscae volitan- tes that are often present in healthy eyes. These smaller opacities are invisible by the ophthalmo- scope, but are readily seen by the patient, particu- larly if he is myopic. They are brought out much plainer in looking against a light wall, a white sur- face, or at the sky on a clear day. In certain cases of eye-strain they become very annoying and assume different shapes, such as strings of beads, rings, flakes, etc. , floating down before the eye. In some patients they are complained of worse during attacks of "bil- iousness." These dark spots before the eyes are variously considered as intra-ocular evidence of waste-tissue accumulation, the results of sexual dis- turbances, etc. Although they become very terri- fying to the patient at times, as a rule they speedily diminish or become ignored when the defective eyes are corrected by the proper glasses and there is rest from excessive ocular labor. The crystalline lens is a biconvex transparent body about one-third of an inch long and less than half as thick, enclosed in an equally transparent, homogene- ous capsule. It rests against the vitreous, and is par- CATARACT. 1 97 tially covered in front by the iris. It is held in place by the suspensory ligament. The substance of the lens is arranged in concentric layers composed of minute fibrils which dovetail into each other. This arrangement gives the lens somewhat the power of a watch-spring, which, when allowed to relax by the contraction of the ciliary muscle, becomes more con- vex anteriorly. This phenomenon is spoken of later in describing accommodation (page 210). Cataract is opacity of the crystalline lens or its capsule, and may be partial or complete. It is not an incurable disease, and does not always cause blind- ness. It is not a ' ' growth on the eye, ' ' and it must not be confounded with corneal opacities. In cataract the cornea is transparent and the iris and pupil are readily seen ; but the pupil, instead of being black, is grayish-white, and the vision may be reduced to the mere recognition of light and darkness. Many people have unripe cataract and are never cognizant of the fact, because that part of the crystalline lens in front of the pupil never becomes opaque. Only a few opaque radii may be seen when the pupil is dilated by a mydriatic. Too much stress cannot be laid upon this fact, as often the oculist, after failing to improve the vision with glasses, is compelled to explain to the patient the reason of his failure, and if the patient is nervous he imagines he has a horrible growth akin to cancer elsewhere, and will become permanently blind. With prescription and frequent changing of the proper glasses, together with the best hygienic precautions and careful systemic treatment, incipient cataract may not only fail to grow worse, but actually clear up to a slight degree. Again, so long as vision remains good 198 THE EYE. in one eye there is no necessity of operating on its cataractous fellow. The causes of simple senile cataract are not exactly known. Old age predisposes to it, but whether by weakened nutrition, general arterial sclerosis, or undue strain on the accommodation in presbyopia, we are unable to say definitely ; but cer- tain it is that cataract is seen less frequently where the care of the eyes is properly understood. It is rare among persons of the better classes who have been careful of their eyes and who have used lenses ordered by competent oculists at frequent intervals, instead of neglecting their eyes or using lenses selected carelessly in an optician's shop or a jewelry store. It is true that the use of proper glasses, the treat- ment of associate local or constitutional disease, and the observance of ocular hygiene may retard or pre- vent the maturing of incipient cataract; but the treatment of mature cataract by drugs or apparatus is useless. When once it is complete there is no cure but a surgical operation. There are frequently adver- tised numerous remedies and treatments "without the knife," which are mostly solutions of some mydri- atic, which by dilating the pupils allow the en- trance of more light and hence improve vision tem- porarily. These are all made with the idea of im- posing on the credulity of the victims of cataract, who are foolishly ready to try any treatment that inay be substituted for the "dreaded operation," which, fortunately, in the hands of a skilful surgeon is almost always successful. The prescribed operation consists in cutting an opening in the rim of the cornea, open- GLAUCOMA. 199 ing the capsule of the lens, and removing the opaque lens from its bed in the pupillary space. Of course, in the place of the lens removed, an artificial lens must be worn in front of the eye in spectacles ; and as great refractive power as well as the power of accommoda- tion has gone with the natural lens, a separate pair of glasses, or bifocal lenses, must be worn for near work. Sometimes in the onset of cataract the crystalline lens swells before it begins to become opaque, and by this change in refraction the aged person is en- abled to read for the first time in many years without glasses. This is the so-called " second sight." However, if the distance vision is taken it will very likely be found quite defective, and generally the typical opacity of cataract progresses, and if the patient lives long enough vision is almost totally lost, and operation is necessitated. Glaucoma is a disease of the eye in which the characteristic symptoms are steadily increased hard- ness of the globe, with pressure and cupping of the optic nerve, and pressing forward of the iris and dilatation of the pupil. It is due either to exces- sive secretion or blocking of the excretory channels of the eyeball. It is a very fatal disease to vision and is very resistant to treatment. It is most com- mon in females and appears generally after middle life. The local medicinal treatment is application of miotic drugs to contract the pupil and reduce the tension. Atropin and other mydriatics, by dilating the pupil, aggravate the condition, and may hasten an incipient attack. Persons with glaucoma are liable to inflammation of the conjunctiva, and are frequently seeking to change their glasses. The careless and 200 THE EYE. indiscriminate use of popular eye-lotions or eye-drops containing some mydriatic in glaucomatous inflam- mation, or the administration by an optician or other layman of a mydriatic preliminary to testing for glasses in cases of glaucoma, has caused the loss of many eyes (see page 222). Injuries to the Eyes. — We have already mentioned the numerous ways in which this delicate and im- portant organ is protected by Nature. The bony orbit and the cushion of fat enclose the eye behind; the orbital margin, eyebrows, eyelids, eyelashes, and nose protect it in front and laterally; while the tough sclera and cornea form coverings not easily pene- trated. When a blow or a foreign body is directed toward the eye, automatically oy reflex action the lids close and the eyeballs roll up, presenting the tough and opaque sclera instead of the important transparent cornea to arrest the force of violence. In fact, in penetrating wounds of the eye directly through the lids the injury is generally on the lower sclera, the cornea having been too quickly rotated upward and out of the line of contact to be injured. Non-penetrating Foreign Bodies. — The most common form of injury is the entrance of small particles of dust, cinder, steel-filings, etc., into the conjunctival sac or into the substance of the cornea. Often the tears will wash such particles as are not embedded toward the inner canthus, where they cause no symptoms and can be seen by the patient and wiped out. However, the foreign body may lodge and be hidden from view in the upper or lower sulcus of the lid or be embedded in the cornea, and can only be seen with difficulty by the unaided eye. It will quickly NON-PENETRATING FOREIGN BODIES. 20I cause intolerable rubbing and grating, which neces- vsitate frequent winking or complete closure of the lid before there is comfort. The eye soon becomes congested and the conjunctiva inflamed. In such cases the surface of the bulbar conjunctiva and cornea should first be inspected in a bright light or by oblique illumination with a magnifying lens. The lower sulcus of the conjunctiva is then brought into Fig. 42. — Preliminary step in everting the upper eyelid. view by simple tension on the lower lid downward with one finger. If the offending particle is not seen, the upper lid should be everted (Figs. 42, 43). This may easily be effected without the aid of a probe or other instrument, and everyone should learn the ma- nipulation, as there is often opportunity in travelling to relieve some unfortunate sufferer by this simple procedure. The patient is told to look down, the 202 THE EYE. edge of the lid and the lashes are seized with the thumb and forefinger of the right hand, and the lid is drawn at first forward and then downward away from the globe; then upward over the point of the thumb or forefinger of the left hand, which is held stationary on the lid and acts as a fulcrum. The foreign body should be removed with a hand- kerchief or wisp of cotton; but if it is embedded it may be necessary for a competent physician to release it with the point of a sterilized needle, or spud, or a Cinier Fig. 43. — The upper eyelid everted. magnet under cocain-anesthesia. Embedded particles are most common in marble-cutters, grinders, engi- neers, firemen, and' the like. In every shop there is some workman who is skilled in removing for- eign bodies, and who does not in his ignorance of the serious consequences hesitate to pick at the em- bedded particle with a rusty knife-blade or needle, without previously washing his soiled hands. De- structive corneal ulcers following such manipulations are not uncommonly seen in large eye-hospitals. Penetrating Foreign Bodies. — The dangers of BURNS OF THE EYE. 203 embedded foreign bodies are not the most serious in these exposed trades. The foreign body often com- pletely penetrates the eyeball, destroying vision of not only the injured eye, but sometimes that of its fel- low by sympathetic inflammation following delayed or improper treatment. There is no more serious injury to the eyeball than penetration by a foreign body, and often vision is not only lost, but also the eyeball must be taken out to avoid sympathetic inflammation. An eye with a foreign body in it is always dangerous, as it is liable to break out at any time into active inflammation. In spite of these dangers the employes in such hazardous occupations refuse to wear protective glasses. There should be a rule in every establishment w^here the nature of the work causes many eye-injuries that no employe shall be allowed to work without protective glasses, gind casualty companies should refuse to take risks on such employes unless this rule is enforced. Penetrating wounds of the eyeball are very serious, especially when through the ciliary region, and often necessitate enucleation. If, however, the lens alone is the seat of injury, a traumatic cataract may be the only result, and this may absorb under appropriate treatment without more serious result than follows an ordinary cataract-operation. Burns of the eye are not uncommon. Usually the conjunctiva and cornea are involved, and immo- bility of the globe or blindness may follow on account of contraction of the scarred membrane and growing of the raw surface of the lid to the ball, with perhaps opacity of the cornea. Quicklime is particularly dangerous to the eye. The most important treat- 204 ^^^ ^yE. ment in such cases is to remove quickly, forcibly, and thoroughly all the irritating substance. This should be followed by the instillation of a drop of concentrated sugar solution. Afterward, a teaspoon- ful of sweet oil may be instilled, and is very soothing. In cases of acid-burns, bathing the eye with milk is advised. Immediately after the first emergency treatment the case should be placed in the hands of a physician. AMETROPIA AND EYEoSTRAIN. The eyeball has very aptly been compared to a camera. Rays of light from a luminous object enter the pupil. The mobile iris acts like the diaphragm of a camera, shutting off rays which are too divergent to be properly refracted, while the remaining rays are focussed accurately on the sensi- tive surface of the retina by the crystalline lens and other refractive media of the eye (Fig. 44). How- ever, here the analogy ceases, for instead of the retina retaining a permanent impression like the sensitive plate of the camera, it is simply stimulated by the impingement of the light-rays, and the impressions caused thereby are transmitted to the centers of sight in the brain by means of the optic nerve, optic tracts, etc. , in a manner somewhat analo- gous to telegraphy. It must be remembered that the eyeball does not see. It is only a sensitive end-organ which receives and transmits impressions to the higher centers of sight. The act of vision is performed in the brain. For the performance of perfect vision the following conditions are necessary: (i) The media of the eye AMETROPIA AND EYE-STRAIN. 205 must be perfectly transparent; (2) rays of light enter- ing the eyeball must be transmitted through the pupil and focussed exactly on the retina; (3) the retina, optic nerve, and its continuations must be perfect; (4) the visual centers in the brain must be intact. In other words, the receiving, transmitting, and interpreting apparatus must all be perfect. A disturbance of any component of the visual system Fig. 44. — A camera obscura and the eyeball compared : A B, object ; d, diaphragm (iris) ; /, lens ; r, sensitive plate (retina) ; a b, image oi A B\ c, cornea. may cause defective vision, and even blindness. In cases of cataract, the retina, optic nerve, and brain may be healthy, but the opaque lens behind the pupil prevents light from reaching the retina. In atrophy of the optic nerve or disease of the retina, the media of the eyeball may be perfectly transparent and properly direct rays of light to the retina, and the brain may be healthy, but blindness ensues because 206 THE EYE. the impressions either are not received or are not transmitted. In disease of the visual centers of the brain the whole eyeball may be normal and the optic nerve perfect, but blindness results from the inability of the brain to interpret the impressions transmitted to it. In this discussion it is with the focussing power of the eyes that we are chiefly concerned. This property of bending nearly parallel rays of light from distance and divergent rays from close range so that they meet exactly on the sensitive retina is called refraction, Emmetropia is the refractive condition in which rays of light entering the eyeball from a distance are focussed exactly on the retina. The emmetropic is the normal eye (Fig. 45). Fig. 45. — The course of light-rays in an emmetropic eye. Ametropia is the refractive condition in which distant rays of light entering the eyeball are not accurately focussed on the retina. There are three varieties of ametropia: hyperopia (far-sightedness), myopia (near-sightedness), and astigmatism. Hyperopia (far-sightedness). — In this condition the eyeball is too short, and rays of light from a distance are focussed behind the retina (Fig. 46, /"). Instead of being distinct as in the emmetropic eye, the image is blurred, and the eye is adjusted for dis- ASTIGMATISM. 207 tance rather than close range. Hyperopia is cor- rected by a convex lens which converges the rays of light, bringing them sooner to a focus. Fig. 46. — Diagram showing a hyperopic eye focussing parallel rays of light at/, behind the retina, and /, the convex lens, which, converging the rays toward r, causes them to be focussed exactly on the retina, thus cor- recting the hyperopia. Myopia (near-sightedness). — In this condition, by reason of greater length of the eyeball or increased refractive changes in the media, rays of light from a distance are focussed in front of the retina, producing an indistinct image (Fig. 47, /). The myopic eye is Fig. 47. — Diagram showing a myopic eye focussing parallel rays at f in the vitreous, and requiring the concave lens /, which will cause them to diverge as from r, in order that they shall be focussed exactly on the retina. adjusted for close range rather than for distance. Myopia is corrected by a concave lens, which diverges rays of light, prolonging the focal distance. Astigmatism is a condition in which the focus may be either in front of or behind the retina, or 2o8 THE EYE. both, but by different amounts for two or more meridians of the eye. In simple hyperopia or myo- pia all the meridians of the eye are equally defective. In simple astigmatism one principal meridian is nor- mal while the other is faulty. In compound astig- matism both meridians are hyperopic or myopic, but unequal in degree. In mixed astigmatism one merid- ian is hyperopic w^hile the other is myopic. Astig- matism does not depend on the length of the eyeball, but upon the curvature of the cornea, and rarely that of the lens. In Fig. 48, a case of hyperopic (far-sighted) as- tigmatism, the meridian vv is normal, focussing at r-^ii Fig. 48. — The course 6^ rays in simple hyperopic astigmatism : h h pass through the hyperopic meridian (after Thorington). z/, exactly on the retina. The meridian at right angles, ///z, is hyperopic, focussing at h\ behind the Fig. 49.— Correction of the astigmatism by a convex cylinder. retina. In this condition a point of light is focussed as a blurred line. Astigmatism is corrected by a cyl- indric lens, which has a plane surface in one axis and a curved surface in the axis at right angles to it. This A CCOMMODA TION. 209 form of lens is really a segment of a cylinder of solid glass. The axis of the cylinder is placed at right angles to the faulty meridian (Fig. 48, hJi). In simple astigmatism, on looking at an astig- matic chart (Fig. 50) with each eye separately, certain of the lines in the defective meridian Fig. 50. — Astigmatic chart. seem very much blurred, while those at exact right angles appear clear and black. This furnishes a test for astigmatism, as to an emmetropic, or normal, eye the lines appear of equal distinctness and black- ness. Astigmatism is very common, and although we speak of hyperopic and myopic eyes separately for purposes of optical explanation, it may be stated that nearly all eyes in highly civilized communities, irre- spective of their length, are in some degree astig- matic. Accommodation. — Until now we have spoken of the eye as an organ at rest, focussed for nearly par- 14 210 THE EYE. allel rays from a distance. Close to the eye the light-rays have an appreciable divergence; yet we know that notwithstanding the inadaptability of the eye for focussing such rays it is quite possible up to middle age to receive distinct retinal images of objects within a few inches of the eye. This change of focus is effected by an act called accommodation, which is accomplished by an in- crease in the convexity of the crystalline lens behind the pupil. This lens is held in place by its suspensory ligament, the tension of which is controlled by the Corneal epithelium Bowniafi s tiiembrane Cornea proper Desceinet' s membrane Corneal endotheliu7n Sphincter of the iris Canal of Schlemtn ^.^^^^^ Ciliary juuscle Cilia ry processes Zonula of Zinn Fig. si. — Comparative diagram showing the change in the shape of the crystalline lens during accommodation. The right side shows the lens at rest. ciliary muscle. During accommodation the ciliary muscle contracts, relaxing the suspensory ligament, and the lens bulges forward by its inherent elasticity and the refractive power is increased (Fig. 51). By means of accommodation all reading, writing, sew- ing, and other near work is made possible. The power of accommodation is greatest in early life, and gradually diminishes until about the age of forty, when reading at the ordinary distance becomes un- comfortable. At about seventy-five years the accom- modation is practically lost. AN ISO ME TR OP I A, 2 1 1 This physiologic failure of accommodation beyond the point of comfortable reading is called presbyopia, or old-age sight, and every person over forty-five years with normal or far-sighted eyes should wear glasses to read and perforni other ocular work. Presbyopia is corrected by convex glasses, which must be strengthened every few years. The presbyopic correction must be used in addition to any distance-correction. Old persons cannot wear the same glasses • for distance and for near. Near-sighted persons, although unable to see dis- tinctly at a distance, are enabled by the increased refractive power of their eyeballs to read without glasses even in old age. Sometimes the distant point of a near-sighted eye is as close to the eye as the ordinary reading-distance (twelve to fourteen inches), and in such cases reading is effected without accom- modation at the far point of the eye. Whenever a person is heard boasting of the ability of himself or some relative to read in old age without glasses, it may be taken for granted that, instead of the vision being extraordinarily preserved, the eyes are near- sighted, and perhaps all through life, distance-vision without glasses has been imperfect, although reading and near work were distinct. Anisometropia, or marked difference in the refraction of the two eyes in the same person, is not unusual; in fact, one eye may be far-sighted and the other near-sighted, and yet the patient, being able to read at a distance with the far-sighted- eye and at close range with the near-sighted one, may go through life never realizing that the eyes are 212 THE EYE. different or defective. Strange to say, persons are sometimes seen who have been almost blind in one eye from childhood, and who have become conscious of this fact only when told by an oculist in later life. However, inequality of the refractive power of the two eyes is very likely to cause severe eye-strain with its accompanying symptoms, which necessitates a visit to the oculist. The Mechanism of Eye-strain. — Comparatively few eyes are perfect. Most persons are slightly far-sighted or astigmatic, but many such persons have apparently perfect vision despite their defective eyes. Near-sighted persons, however, always show defective vision, although near vision may be perfect and close work may be done comfortably without accommodative strain; in fact, acquired near-sighted- ness is by some considered as an attempt of Nature to produce an eye adapted to the increasing ocular labor of modern civilization. The question naturally follows. How can far- sighted or astigmatic eyes secure for their owner per- fect vision? The answer is, Simply by the use of accommodation. By constant strain on the ciliary muscle the crystalline lens is so increased in curva- ture as to counterbalance exactly the optical defects of these eyes, and so long as the accommodation holds (/. e. well into middle life) the patient has no trouble in distance vision. If he follows an outdoor occupa- tion, and has little use for his eyes at near work, and his health keeps good, there is no consciousness of eye-strain. But if the employment is indoors in a clerical occupation or in reading and in studying, or if the general health fails, there may develop from THE LOCAL SYMPTOMS OF EVB-STkAlN. 21 3 the incessant loss of nervous vitality in eye-strain a chain of symptoms collectively known as astheno- pia. The multiformity of the effects of eye-strain can only be properly realized when we understand how vital the function of vision is to every act, emotion, or thought. The visual centers are in the closest connection with the other brain-centers, and the slightest disturbance of the visual mechanism, par- ticularly if the eyes are used excessively at close range, produces sympathetic irritation not only in the eyes, but in the entire motor, sensory, and psychic systems. Happily the manifold efifects of eye-strain, so long ignored, are being better appreciated every day, and cases of chronic inflammation of the eyes and persistent headaches are quickly sent for exami- nation of the refraction of the eyes instead of being dismissed with a time-worn formula for medicine. The Local Symptoms of Eye-strain. — There may be a continual sense of discomfort in the eyes, which organ may even become very painful if used for near work. After a few moments of reading the type blurs and the letters run together, and there may be a difficulty in following the lines. There may be twitching of the eyelids, and in extreme cases there may be great difficulty in keeping the eyes open in continued reading on account of drowsiness. The eyes may smart, itch, or burn, and continually "water;'* or they may appear red and congested both on the edges of the lids and in the conjunctival sac. A com- mon symptom is the appearance of "styes," often only relieved by the use of proper lenses. There may be distressing sensitiveness to light. 214 THE EYE. The General or Reflex Symptoms of Eye-strain. — One of the commonest reflex asthenopia symptoms is headache, particularly that accompanied by nausea ("sick-headache") and made worse by reading, sew- ing, riding in the cars, riding backward, shopping, attending the theater, etc., although often there seems to be no particular connection with excessive use of the eyes. The headache is usually temporal or frontal, but it may be on the top of the head or at the base of the skull (occipital). The headache may be of the neuralgic type, and may be limited to one side, and then not always on the side of the more defective eye. In some cases the reflex disturbances are quite remote from the eyes, and escape connection with eye-strain. Obstinate constipation and indigestion are occasional manifestations of eye-strain. Ver- tigo, general nervousness, nervous prostration, in- somnia, and even chorea and epilepsy are some ot the influences of asthenopia on the nervous system. In fact, the general health may be so impaired by the continual nervous drain of eye-strain that the most serious systemic debility may result. Unless the patient has been under the care of a skilftil physician, who recognizes the influence of eye-strain, he may be medicated, massaged, dieted, and given many other forms of treatment before the services of an oculist are sought. The liability to overlook eye-strain as a reflex cause in systemic troubles is in no small degree due to the fact that often when the reflexes are most prominent there is little or no local disturbance to direct the attention to the eye, and the same is true of the con- THE EYE-STRAIN OF MYOPES. 215 trary. It may be mentioned here that often patients with prominent eye-symptoms may persistently seek relief from local treatment when the cause is not ocular. For instance, patients are sometimes given glasses by unscrupulous opticians for conjunctivitis which may be of purely nasal origin. Again, there is pain deep in the orbit, associated with a dull headache, particularly distressing on arising in the morning, in some varieties of uterine disease. The orbital pain and brow-ache of malarial fever may be mistaken for an asthenopic reflex. How- ever, the history of chills and fever will prevent a physician from making a false diagnosis. In the early stages of locomotor ataxia the eye-symptoms may be carelessly dismissed with a prescription for glasses, allowing the disease to progress unrecognized. Such cases are unanswerable arguments for the neces- sity of medical supervision in the diagnosis and treatment of eye-strain. The Eye-strain of Myopes. — We have spoken heretofore of the asthenopia due to hyperopia and astigmatism which may be unrecognized on account of preservation of perfect vision. There is still to be considered myopia, in which near vision may be comfortable although the distant vision is faulty. No amount of eye-strain will improve the distance vision, because the more a near-sighted person strains the ciliary muscle the more myopic he becomes. It would naturally be supposed that such a person would immediately seek relief from an oculist on account of poor distant vision. On the contrary, many near-sighted persons, not being accustomed to any better distant vision, and being able to perform 2l6 THE EYE. the finest work without effort, are likely to boast of their strong eyes. When given correcting-glasses they may even discard them, saying, perhaps, that objects at a distance look unusually bright or clear, but that they prefer the old familiar haze. Despite all arguments to the contrary, the myope is quite as much in need of glasses as the hyperope or the person with simple astigmatism. On account of the stretching of the ocular coats the nutrition of the structures of the eye is disturbed and often the membranes are vitiated almost to a point of true disease. In reading, the myope is inclined to hold his book close. In so doing he strains his muscles of convergence, producing ocular congestion and compression of the eyeball, and by bending over he affords a favorable position for distention of the ocular veins. Contrary to popular impression, the uncorrected myopic eye may be considered a "sick eye," and unless restrictions are made as to the amount of near work performed or unless the proper glasses are ordered, permitting reading at a safe distance from the eye, serious progress of the myopia with accompanying intra-ocular disease may occur. It is particularly necessary to pay the strictest attention to school hygiene (see page 235), and to correct repeatedly the constantly changing refraction of the eyes of school-children in order to prevent the serious higher grades of myopia. Moderate degrees of myopia which have been properly cared for may never cause the patient any discomfort other than the necessity of wearing glasses constantly. Even if there were no danger of the progress of myopia or intra-ocular disease, the slight inconvenience of THE OCULAR MUSCLES. 217 wearing glasses is many times offset by the improve- ment in distant vision, allowing participation in out- door sports and in the pleasures of Nature. The Ocular Muscles.— The eyeball is moved by six muscles, namely, the superior, inferior, internal, and external recti, and the superior and inferior ob- liques (Fig 52). The disorders of the ocular muscles Levator of the upper eyelid Superior rectus External rectus. Ififerior rectus. Superior oblique Internal rectus Inferior oblique Fig. 52. — The external ocular muscles. are of sufficient importance to be mentioned here, par- ticularly as squint, muscular imbalance, and muscular insufficiency are mostly due to ametropia, notwith- standing popular beliefs to the contrary; and they may be prevented by the early prescription of glasses, and often alleviated or entirely cured by the same treatment. Paralysis of the ocular muscles is usu- ally the result of serious systemic disease. When the visual axes of the two eyes meet ex- actly at the point of observation, the ocular mus- cles are said to be balanced (Fig. 53). This mus- cular balance is maintained by the perfect anatomic conformation of the muscles and equally distributed innervation to them. Any disturbance of these fac- 2l8 THE EYE. tors Upsets the muscular equilibrium. If the inser- tion or structure of a muscle is faulty, or if the innervation is anomalous, muscular imbalance, or heterophoria, is produced. This, however, does not imply that binocular fixation becomes impossible. On the contrary, the visual axes may be rightly directed by increased innervation, and single vision maintained in ordinary work. In true strabismics Fig. 53. — Diagram showing the eyeballs in proper position during conver- gence, the visual axes exactly meeting at A. or squint, or permanent deviation (Fig. 54), this is not possible, and diplopia (double-vision) is only avoided by the use of correcting prisms or by forcing one eye from participation in the visual act. In other words, in true strabismus, perfect binocular vision is impossible without optical assistance, while in ordinary muscular imbalance, or heterophoria, binocular vision is maintained by increased inner- vation. In the first, the anomaly is in some part THE CAUSE OF MUSCLE-DEVIATIONS. 219 organic; in the last, exclusively functional. The importance of the study of the functional anomal- ies of the ocular muscles is manifest when we realize that the extra expenditure of nervous energy in main- taining perfect binocular vision causes asthenopic and reflex symptoms quite as annoying as those due to errors of refraction. The cause of muscle-deviations is almost alwavs Fig. 54. — Diagram showing the eyeballs in a case of strabismus. The visual axes meet at B instead of at A. a refractive error. For many years it was supposed by some authorities that the defect was anatomic; that the muscles concerned were too short, too long, or anomalously inserted or attached; and that the only remedy was surgical intervention by means of section of the tendon (tenotomy) and advancement. To-day, we know that in all cases of muscular devia- tion not the result of paralysis, the prescription of the proper glasses is the first treatment. In young 220 THE EYE. children the squint will usually disappear after the glasses are worn, but if correction of the ametropia and properly prescribed exercises do not restore mus- cle-equilibrium after several months, then the surgi- cal measures may be tried. The involuntary, or automatic, movements of the eyes, such as the rotation in reading, are intimately associated with the act of accommodation. For instance, when a book or paper is brought close to the eye there is an innervation to the ciliary mus- cle, forcing it into action, thus changing the focus of the crystalline lens, so that it will receive rays of light from the near object and place them exactly upon the macula of the retina. At the same time the two eyes must converge in order that their visual axes shall meet exactly at the near object; otherwise there would result confusion of images, or diplopia. In the same way the eyes must be rotated in or out, up or down, with a definite exactness, according as the object is held to the right, left, above or below the vertical and horizontal visual planes, otherwise the visual axes would not meet exactly at the point of observation. Whether congenital, or by long habit — the development of automatism — these move- ments of the eyeball are intimately associated, likely controlled by one center or contiguous centers, as far as participation in near work is concerned, and there is a constant relation maintained between the acts of accommodation and ocular movement. This is par- ticularly so with convergence, and long ago the theory that "squint" is caused by excessive stimulation of the adduction (convergence), associated with excessive accommodation in hyperopic eyes, was propounded USE OF MYDRIATICS. 221 and has never been successfully controverted. The same is true of muscular imbalance. Attention to the ametropia often speedily relieves the muscle- defect. It is careful refraction, and not surgical operation, that prevents and cures most of these cases. If operation should restore muscle balance, the un- corrected causative eye-strain is still operative, and unless corrected by glasses there may be a recurrence of the deviation, or equally serious reflex asthenopic symptoms may ensue. The reason that oculists use mydriatics, or "drops," as they are popularly called, in measur- ing the refraction of the eyes is frequently asked for by the laity, and there is a popular impression that from the name they are used only to dilate the pupil. Mydriatics are used in refraction of the eye to produce paralysis of the ciliary muscle; in other words, as cycloplegics. With the accommo- dation active in far-sighted and astigmatic persons, it is impossible to discover the full defect on account of the continual compensatory strain of the ciliary muscle. Hence by using a substance in the eyes such as belladonna or its alkaloid, atropin, which paralyzes the ciliary muscle and puts the eye in a state of rest, *the interference of accommodation is overcome. A far-sighted or astigmatic person with perfect visual acuity when the ciliary muscle is active, will see as poorly at distance under a mydri- atic as an equally near-sighted person, because of ciliary paralysis (cycloplegia); and as there is no ability to strain left, the full amount of the defect is unmasked. Without a mydriatic, far-sighted and astigmatic persons refuse their full correction, while 222 THE EYE. near-sighted persons are liable to select glasses too strong for them. When the accommodation has failed in old age a mydriatic is not necessary, but it is a safe rule to follow, always to use a mydriatic in first refraction of persons under forty-five years of age, and often ciliary paralysis is necessary for accurate refraction of robust patients of even fifty years. Per- sons advertising to examine the" eyes of children and young adults accurately without the use of mydriatics are claiming what is impossible even to the skilled oculist. The Objections to Mydriatics. — When "drops" are put in the eyes the resultant paralysis of the ciliary muscle makes close work, such as reading and sew- ing, impossible. When atropin is used this incon- venience is continued for ten days or two weeks, but, contrary to popular opinion, there is no danger attending the ciliary paralysis; in not a single case has it become permanent. Accommodation returns promptly after the effect of the drug has passed off, leaving the eyes better for the rest from near work. The length of time necessary to abstain from near work is now shortened to from thirty-six to forty-eight hours by the use of a new mydri- atic called homatropin, which many oculists use in routine practice among adults. In children, time is not so valuable, and as complete paralysis of accom- modation is more difficult to obtain, the stronger mydriatic, atropin, is preferable. There is a disease of middle and later life, called glaucoma, in which the use of a mydriatic may pro- duce very serious results; and opticians, jewelers, and other non-medical " refractionists " who are forbid- VISUAL TESTS. 223 den by law to use ''drops," have made a great card of this fact. This disease is, however, very rare, and is readily recognized by the trained oculist, who always makes careful external and ophthalmoscopic examina- tion before prescribing a mydriatic or ordering glasses. Although there is no danger from the use of " drops " in the hands of the skilled physician, their promis- cuous employment by itinerant opticians, jewelers, peddlers, and the like, may result disastrously to persons with glaucoma, who by reason of their fail- ing vision are particularly likely to be seeking a change of glasses. VISUAL TESTS. Testing the Acuity of Vision. — It has been proved that rtie smallest retinal image perceived at the macula corresponds to a visual angle of 5'. Follow- ing this principle, test-types have been constructed in such a manner that every letter is so made that when at its proper distance it subtends an angle of 5'. The letters in Fig. 55 subtend an angle of 5' when Fig. 55.— Two of Snellen's test-types. FiG. 56.— Test-type for the illiterate. placed about twenty feet from the eye, and should be read easily at that distance if the eye is normal. For illiterate persons and children, a card containing characters such as in Fig. 56 may be used. The patient is asked to tell which way the prongs of the E point — upward, downward, to the right, or to the left. The only article required in testing distant vision 224 THE EYE. is a series of test-letters (Fig. 57) so arranged that they subtend an angle of 5^ at varying distances from 10 to 2CX) feet. The distance may also be ex- pressed in meters. These cards may be procured for a merely nominal sum at any optical store. Figs. 55 and 56 placed at 20 feet distance may be used by the reader for the simple purpose of find- ing out whether or not vision is normal. In using: the larere card of test- EFeet , . ^. ^ ^ ^ ^ , letters, it is fastened to a hook 200 or nail about 6 feet from the floor, and about 20 feet from the chair in which the patient is seated. The letters of the 20- foot line are then about on the level with the patient's eye. The card must be well illumi- nated by daylight or artificial light. The 20- foot distance is not necessary; 12 feet will an- swer, but in this case we must bear in mind that the patient should read several lines lower. Always examine each eye sepa- rately. Seat the patient facing the card; direct his attention to the test-letters; cover the left eye with a small card and ask him to read on the test-card as low down as possible. Note the lowest line read correctly or nearly so, and then cover the right eye and test the left in a similar manner. Register the findings as follows: If the card is hung 70 C B D I. N P T B Rs F Z B D S40 O F L C T G 30 APSORFDZ 20 VPRTVZBDFBKO 15 Fig, 57. — Reduced illus- tration of an ordinary card of test-letters for measuring the acuity of distant vision. VISUAL TESTS. 22 5 at 20 feet distance, use 20 as the numerator and the number of feet at the side of the lowest line read as the denominator. This gives the visual fraction. For instance, if the patient reads the line marked 40 feet (that is, consisting of letters subtending an angle of 5' at 40 feet), his visual fraction is ff. Any fraction less than f J indicates defective vision. But it must be borne in mind that the mere fact of the patient readi7ig the f^ line is 7io assurance of the absence of refractive error. The patient may be hyperopic and astigmatic (if in youth, to a very con- siderable extent), and still read the \% line by means of his accommodation, and it is this very extra strain that causes the distressing asthenopic symp- toms. This can be definitely determined only by the use of a mydriatic. If the patient already wears glasses, and with them he cannot read with each eye separately |-§-, he shoul(i consult an oculist. If there is considerable difference of vision in the two eyes, there is great likelihood of eye-strain. If the symptoms cannot be traced to any other cause, or if the patient uses the eyes excessively or viciously, or if the symptoms are especially referred to the eye, even though the vision appears normal or properly corrected with glasses, the physician should put one drop of a 2 per cent, homatropin solu- tion into one eye every five minutes for a half hour, and then if the vision falls to any great extent the patient is ametropic, likely hyperopic or astigmatic. Myopic persons without astigmatism see about as well at a distance under a mydriatic as when the accommo- dation is functional. 15 2^^ THE EYE. If the patient is young or is not compelled to use the eyes in his daily vocation, and complains of per- sistent eye-pain or headache untraceable to other causes, the eyes should be put at rest under atropin for teu days, and tested. This is accomplished by the in- stillation three times daily for two days of one drop of a I per cent, solution of atropin into each eye. If the vision falls under the mydriasis, or if the symptoms are relieved, the diagnosis of ametropia is positive. Testing Accommodation. — The small reading test-card or paper is brought slowly up before each eye separately, the other being covered, and the patient is told to fix his gaze on type of about the size shown in the following paragraph: Measures preventing the development of myo- pia consist in the careful examination of chil- dren's eyes, part'cularly about the time they are to start to school, and in securing the best hygi- enic conditions for ihera during their school hours. Good ventilation, properly constructed deslis, and sufficient and rightly directed light If he is younger than 21, he should be able to read the type easily at from 5 to 7 inches distance, other- wise he is considerably hyperopic or has some extra disturbance of the ciliary muscle, and his case is one for an oculist. If the patient is middle-aged and cannot see the type easily at 10-12 inches, he is either presbyopic or hyperopic, and is in need of reading-glasses. If there is a discrepancy in the reading-power of the two eyes, the case is especially one for an oculist. If the patient has very poor dis- tant vision, but can read the type easily at 5 inches, he is a myope. If the patient is alread}^ wearing reading-glasses and the type cannot be read with each eye at 10-12 inches, his glasses are not strong enough. COLOR-BLINDNESS. 22/ If he cannot read the type with his glasses at a dis- tance of at least 14 inches, his glasses are too strong. Color-blindness. — Total color-blindness is very rare. In such cases the entire solar spectrum ap- pears grayish. Partial color-blindness is generally congenital. It is often hereditary, and sometimes skips several generations. The discoverer of color- blindness was Dalton, a distinguished professor of chemistry, who himself was color-blind, a fact which he ascertained by accident. Acquired color-blindness may be the result of disease or accident. Defective color-sense often ap- pears after disease of the optic nerve, and is a par- ticular symptom in optic neuritis and atrophy due to excessive use of tobacco and alcohol. However, central color-blindness may be seen in all forms of toxic amblyopia. A peculiar point to be noted in tobacco-amblyopia is the fact that the patient may be able to distinguish colors close to the eye, but when they are farther removed he is color-blind, partic- ularly for green and red. This makes it quite im- portant to test for color-blindness at the normal signal distance in addition to the skein-test at close ranee. Color-blindness is sometimes the result of injury; occasionally, after blows upon the head, color-blind- ness is noticed in one-half the field of vision only, the other half being normal in its color-perception. Partial color-blindness is quite common. Statis- ticians tell us that the proportion is i : 25 among males, and I : 400 among females. There ma}^ be blindness to blue, yellow, red, or green. However, the colors that most often fail to make proper impressions are red and its complementary color green. These colors 228 THE EYE. do not appear as absolutely black, but they cannot be distino^uished from one another and from certain shades of gray and brown. In extreme cases there is total blindness for red and green, and even the brightest shade of red cannot be distinguished from green. Unfortunately, the colors most often at fault are those selected by railroad companies and naviga- tors as their signal colors; hence, we see how im- portant it is for the employes of transportation com- panies to have the color-sense absolutely perfect. In the ordinary Holmgren test, the person is given a test-skein of wool of a light-colored pink, and told to select (and not name) from a mass of similar skeins those which most nearly resemble the skein to be matched. If he is color-blind, he will confuse the grays, the greens, the pinks, the browns, and the reds. As a confirmative test he is then given a light, pure green skein to match in the same way. It is presupposed that the examiner is not at all color- blind. Dr. Vi^illiam Thomson has devised a convenient apparatus for testing for color-blindness, which has been widely adopted by railroad examiners. It con- sists of a stick to which numerous bundles of yarn are attached, a light green being used as the test- skein. The method of using the Thomson stick is described by its author as follows: Using the light- green test-skein, the patient under examination is asked to match it in color from the yarns on the stick, which are arranged in alternate green and con- fusion-colors, and which are numbered from one to twenty. The selection of ten tints is required, and the examiner notes the number of the tints chosen. TESTS FOR BLINDNESS. 22g The odd numbers are green and the even ones the confusion-colors. If the patient has a good color- sense, his record will exhibit none but odd numbers; if he is color-blind, the mingling of even numbers betrays the defect. To distinguish between green- blindness and red-blindness, the rose-test is used, and the color-blind patient will select, indifferently, either the blues intermingled ^ith the rose, or, per- haps, the blue-greens or grays. Finally, the red test is used as a control. There are other color-tests, but these two are suffi- cient for practical purposes. The field for vision for different colors is tested in the same manner as the field for white, using a colored object instead of a white one. Tests for Blindness. — Hysteric amblyopia is not uncommon, but very many cases so diagnosed are properly the sequence of asthenopia. Malingering by the declaration of amblyopia or blindness may be found in insurance-examinations and in military life, and often to procure damages after alleged injuries. Many ingenious devices have been adopted to expose the simulant, all depending upon the fact that in or- dinary visual perception there is no account taken of the exact participation of the two eyes. If we hold a book before the patient's eye and interpose a pencil in front of the eye supposed to be active, the reading will be slightly interrupted if the left eye is ambly- opic; if, however, the amblyopia is feigned, the left eye will escape the pencil and the reading will be uninterrupted. Another way is to interpose a highly convex lens in front of the eye supposed to be good, and if the test-type is removed beyond the 230 THE EYE. focal distance of the lens and is still legible, we know that the other eye participates in vision. The pro- duction of double images by the interposition of prisms also proves binocular vision. Still another method depends upon colored letters placed upon a dark background which cannot be seen through glasses of complementary colors. A person looking at green-blue letters on a dark ground through a red glass over the sound eye, and a white or green glass over the alleged blind eye, will be unable to see the letters if the allegation is true. THE GENERAL CARE OF THE EYES AND SCHOOL- HYGIENE. The care of the eyes in earlier childhood is as equally important as later. From the moment of birth the eyes should be carefully watched. Ophthalmia neonatorum, a disease appearing be- tween the first and third days of life, and commonly known as "babies' sore eye," is responsible for a large proportion of blindness. The moment the mother or nurse notices the appearance of an inflam- mation of a child's eyes during the first week of life, a physician should be summoned, and his directions as to repeated cleansing should be rigorously carried* out. Infants' eyes should never be exposed to the direct glare of the sun, either indoors or outdoors. In the crib or bed the baby's face should be turned from the window. When out in its coach it should be protected when lying down by a parasol or awn- ing, preferably lined with some dark-colored material that will not reflect the lio^ht. Youne children should THE DANGERS OF THE KINDERGARTEN. 23 1 not be encouraged to play with toys that require close inspection. If blocks, letters, or picture-books are allowed, they should be so large as to be easily seen at some distance from the eye. Even very small infants are better out of doors on a clear day, and when they can walk, they should be romping about in games or looking at distant objects, rather than using their eyes at close range. General physical exercise rather than ocular and intellectual labor is desirable in young children. As the child grows and associates with playmates or schoolmates every precaution should be used to prevent its infection from granular lids and acute conjunctivitis ("pink eye"), as well as from other contagious diseases. It must not be allowed to use the same towel, handkerchief, or drinking-mug that is used by its companions, and it should especially be restricted from playing with children who have ' ' sore eyes. ' ' The Dangers of the Kindergarten. — There is a very fashionable practice now prevalent of sending very young children, particularly when restless and hard to amuse, to so-called kindergarten schools, where they play with small objects or look at pictures, or sew at close range. This is a distinctly injurious custom. Very young children should be discouraged from all near work, and in day-nurseries and primary schools the most of the teachino^ reouirino^ visual labor should be by large pictures and charts hung at some distance from the pupils' eyes. If a child has red eyes, holds its book close, com- plains of not being able to see at a distance, looks at objects sideways or between partially closed lids, or 232 THE EYE. squints or complains of headache, browache, or pain in the eyes, it is the parents' or teachers' duty to send it to a competent oculist. If the oculist decides that glasses are necessary, they should be put on at once in spite of any foolish prejudices, for they will save and promote the physical and intellectual develop- ment of the child and prevent many years of suffering and perhaps irreparable ocular disease. Young children with defective vision or hearing are often called stupid and inattentive, and actually punished for physical faults which should have been detected and remedied long before. The question is often asked, " When shall a child begin school ? " This, of course, depends entirely on the child's health and the condition of the eyes. If the eyes are defective and show a great tendency to astigmatism or myopia, the mental education should be postponed and systematic study should not be started until the person is twelve years of age, when the ocular tissues become more resistant. In the meantime the child should be instructed judici- ously at home or in shortened courses at school. Outdoor exercise and properly assigned manual labor should be urged. If the child is of poor parentage and must go to public school, it will be better to post- pone the schooling for a few years and enter later a class of children below its age, explaining to teacher the reason of the deficiency in education. Ordinarily a healthy child with normal eyes may begin school at from eight to ten years of age. It then arrives at systematic study after its ocular tis- sues are well formed. Of course, if the proper pre- cautions, of which we have much to say later, are CARE OF CHILDREN'S EYES AT HOME. 233 practised, the entrance age may be lowered somewhat. No child of tender years should be encouraged in prize competitions; in fact, it would be better if there were no grading in the primary schools other than by term average. The ambitions of parents sometimes lead to ruin of a child's eyes and health. Care of Children's Eyes at Home. — Continuous close work is most detrimental to the eyes of children. Sometimes parents allow the evils of school-life to be repeated at home. No provision is made for proper lighting and seats. Children are often allowed to read story-books and novels as much as they please, and until late at night in a poorly lighted room or in front of a fireplace, and often in stooping or recumbent positions. All this is wrong. Such children are generally over-ambitious in school, and not only should be compelled to take intervals of rest from close work during the day, but also should be discouraged from using their eyes in read- ing, writing, or sewing at night. If some home study is necessary, the proper lighting, chairs, and desks should be provided. The pernicious influence of modern school-life upon the eye as well as upon the general health is not sufficiently recognized by parents and teachers. Nearly all knowledge is acquired to some extent by the use of the eyes, and if the proper hygienic pre- cautions in vision are not heeded, the evil effects of eye-strain upon the whole body may be most serious. With the advance of civilization there is a constant increase of visual defects and of general physical degeneration among school-children. The causes are many. The most prominent are: imperfect cou- struction of school-houses, imperfect lighting, foul air, crowding, poor ventilation, long hours of con- tinuous application at close work in school and neces- sary extra preparation after school-hours, frequent and trying examinations, and poor print and paper in school-books. Until recently there has been a disregard on the part of public authorities and educational chiefs of the advice of physicians in matters of public hy- giene. Happily this is being overcome through the efforts of the intelligent mass of the community and the patriotic efforts of the physicians themselves, who have often given advice and time willingly and without compensation. We hope soon to see the time when all persons seeking election as school- directors, educational trustees, superintendents of schools, etc., will be subjected to a non-partisan examination or be compelled to show qualification in the principles of school-hygiene. There should also be salaried medical inspectors, controlled by prominent chiefs, to whom they will be responsible for the performance of their duties. These physicians should systematically examine the eyes as well as the general health of every school- child before entrance and during the tender years of school-life. It is essential that the teachers should be instructed in all the elements of school-hygiene. The Development of Ametropia in School-chil- dren. — The eyes of a child at birth are hyperopic and ill-adapted for close work. The ocular tissues are delicate and soft. If excessive near-work is allowed, the pressure of the tense ocular muscles on the eyeball, together with the blood-soaking of SCHOOL-HYGIENE, 235 tissues from constant or prolonged ciliary conges- tion, causes the coats of the eyeball to become viti- ated and pressed out of shape, and refractive error develops. There is unanimity of opinion in the numerous statistical studies upon this subject. Most school-children's eyes are defective and gen- erally astigmatic; the hyperopic eyes outnumber the normal and myopic eyes, particularly in early school- life. As the higher grades are entered high myopia and progressive myopia with choroidal disease be- come more and more numerous, until the proportion of near-sighted eyes in some of the higher continental universities is as high as 50 per cent. Strange to say, in the development of myopia starting primarily in the hyperopic eye, emmetropia is seldom attained, the disease progressing from hyperopia to myopia, as it has been aptly said, "through the turnstile of astigmatism." In this country the development of myopia has been much lessened by the efforts of oculists to show the intelligent members of the community that much eye-trouble may be offset by regulation of study and reading and the use of proper glasses, with frequent re-examination of all children who show any symp- toms of eye-strain. However, there is much to be accomplished in the construction of school-buildings and the regulation of the ocular labor in schools. School-hygiene. — In view of the importance of eye-strain and ametropia in retarding the intellectual and physical development of children it has been thought advisable to discuss separately each of the more important faults that are found in modern school-systems. 236 THE EYE. The location of a school-building should be so chosen as to secure the best sanitary environment, if possible on a wide street, remote from any adjacent high buildings, if possible in the center of a lot large enough for a surrounding campus, or playground. It has been found that ocular defects are always more numerous in schools on narrow streets or in close proximity to high walls, and also that children on the lower floors of such school-houses have the worst eyes. It has also been found that there is much less myopia in the primary schools of rural districts. The light should enter the room directly, and not by indirect reflection from an adjacent wall. The northern light is the most constant. However, the hygienic advantage of having the sun in the rooms during some portion of the day, as is afforded by the other exposures, is not to be overlooked. Exces- sive sunlight in the warmer months may be controlled by the use of awnings and shades. An oblong room allows better lighting than a square room. The windows should be numerous and spacious, with large panes of glass, which should be kept clean. They should be so placed that the light may come from the left or from the left and rear of the desks. Light coming from the right produces annoying shadows of the pupils' hands and arms on their books and papers. Light coming from the rear is obstructed by the pupils' backs and also produces shadows. Light from the front is the worst of all, as it may be so dazzling as to greatly embarrass vision. One has only to look at a picture hung between two windows to realize this. Overhead or sky-lighting is an excellent form of securing THE SCHOOL-ROOM. 237 illumination, but it is only practicable on the top floors. It contributes much annoying heat in warm weather and interferes with proper heating in the winter. Cross-lighting by windows on opposite sides of a room produces very annoying shadows. There should be at least one square foot of window- space to each four square feet of floor-space. How- ever, there cannot be too much window-space, as excessive light may easily be controlled, while artifi- cial illumination is the only remedy for a deficiency of daylight. It must be remembered that the lower floors require the largest window-space. The dimensions of an ideal school-room given by Risley, who has carefully studied this subject, are as follows : Feet. Height of ceiling 15 Length of room 32 Width of room 24 Pier or blank wall, rear of room 4 Pier or blank wall, front of room 4 Space allotted to group of windows 24 Window-sill from floor (bevelled) 3 Top of window from floor 14 Height of window II This arrangement affords a total capacity of 11,520 cubic feet, or 256 cubic feet for each of forty-five pupils. The sills should be at least four feet above the floor, so that the light will come over the pupils' heads. Light coming in below is worse than useless, and must sometimes be shaded. There should be no more wall-space above the windows than neces- sary, and the sills should be bevelled to admit the maximum amount of light. 238 THE EYE. The window-shades should be of the ordinary Holland style, either lig-ht gray, buff, cream, yellow, light blue, or green. There should be two for each window, so that the upper or lower half of the win- dow, or both, may be shaded as desired. The walls and ceilings of a school-room should be of some light reflecting color, such as advised for the shades. Colors near the red end of the spectrum, such as terra-cotta, absorb too much light to be used. Light-colored woods, such as oak, are preferable to walnut and other dark woods for use in the doors, window-frames, book-cases, etc. There should be as little wall decoration, such as charts and pictures, as possible, and a minimum of blackboards. A simple test to determine the efficiency of the lighting is to attempt to read small print in the remotest corner of the room on a cloudy day. Arti- ficial lighting should never be needed during school- hours. The desks and seats should be so arranged in re- lation to the windows that the light comes from the pupils' left or from the left and behind. Under no circumstances should the desks face the windows. Some arrangement must be made so that the teacher will not confront the direct glare continuously. The desks and seats should be adjustable. It is very wrong to make children of all sizes sit at a uniform- size desk. Let the average size desk be generally used, but for oversized or undersized children the desks should be properly adjusted, and to avoid extra trouble these children should keep the same seats during the entire term. The common faults are unsuitable shape of back, DESKS AND SEATS. 239 too great a distance between seat and the desk, dis- proportion in the height of seat and desk, and incor- rect shape and slope of the desk. The edge of the desk should slightly project over the edge of the seat. The top of the desk should in- cline downward from the horizontal about ten degrees toward the student, and be low enough to allow the ¥ Fig. 58. — Position assumed in writing with the desk too high. forearm to rest without raising the shoulder. The seat should be sufficiently broad to support almost the whole thigh, and close enough to the floor to allow the sole of the foot to rest on the floor. It should be slightly concave, to prevent slipping, and horizontal rather than inclined. The back should be so curved forward as to support the loins sufficiently 240 THE EYE. and to make it easy and comfortable for even weakly children to sit upright. If the seat is too high, the child cannot touch the floor, and is uncomfortable and does not get proper aid from the legs and feet to maintain an upright position. If the desk is too high, the elbow can only rest by curving the spine and raising the shoulder (Fig. 58). The work is also brought close to the Fig. 59. — Position assumed in writing with the desk too low. eyes and causes extra strain. If too low, the child stoops over the desk and becomes round-shouldered (Figs. 59, 60). This position also necessitates great strain on the accommodation and compresses the superficial veins of the neck, leading to ocular and cerebral congestion with its pernicious consequences. Blackboards, charts, and maps are valuable aids in instructing children, because by them information BLACfTBOARDS, CHARTS, AND MAPS. 241 may be imparted at a distance and the strain of accommodation in near work dispensed with. All figuring or lettering must be sufficiently large to be perfectly legible in any part of the room. Even to those of moderate visual acuity, such characters, to be read at a distance of forty feet, should be at least one Fig. 60. — Comparative diagram showing the proper position at a desk, a ; the position when the desk is too Ipw, b ; and the position when the desk is too high, c. (After Cohn.) and one-half to two inches high. The same precautions should be exercised in writing on the blackboards. If these requisites are observed, then when a pupil fails to see the contents of charts, maps, or blackboards from any part of the room, it is certain that there is a serious error of refraction or disease of the eye le 242 THE EYE. requiring immediate medical attention. Blackboards should be kept clean with sponge and water, and as dark and as free from gloss as possible. There is not sufficient contrast of the white chalk on a very dirty grayish-black board, on which only a common eraser has been used. White boards with black crayons, although affording a greater contrast, necessitate soil- ing of the fingers to such a degree as to be imprac- ticable. Copying from the blackboard should be avoided as much as possible, as it is very trying to the eyes on account of the constant change of focus from the desk to the board. Blackboards and charts should never be placed between windows, but always opposite the source of light. Slates are unclean and unhygienic, and often afford too little contrast. Pencils or pen and ink and dull white paper are suitable substitutes. Regulation of Study. — In the lower grades es- pecially there should be such regulation of the studies that reading or writing after school-hours is unneces- sary. The studying should be done in school. The curriculum should be so arranged that wherever pos- sible oral instruction and demonstrations with maps, charts, or blackboards are substituted for study from books. The curriculum of primary schools should bf so elastic that pupils in poor health or with defective eyes may be excused from the full course of instruc- tion. Prize competitions or term-examinations should not be allowed in the primary schools. Fre- quent intervals of rest, such as are afforded by conver- sations, lectures, and recesses, are very desirable. One SCHOOL-BOOKS. 243 daily session of two or three hours is sufficient for the smaller children. Medical examination of school-children is most desirable. Every child should show a medical cer- tificate of good health and satisfactory vision before being allowed to enter school, and an annual re-exami- nation should be made at the beginning of each term. The teachers may be instructed by the school physi- cians in the elements of medical examination and in the grosser tests for hearing and vision, and thus become of great assistance to the medical staff. Children with faulty eyes should be sent to an oculist or to an ophthalmic hospital for treatment and for advice as to the advisability of continuing with their studies. School-books should be small enough to be easily handled, and ought to be printed in easily legible type on dull-surface paper. Cohn insists that in schools all books should be forbidden that contain smaller type than long primer (about 10 point) and a less interval than one-tenth of an inch between the lines. No line should be over four and one-half inches long, nor contain more than sixty letters. The following remarks apply as well to books and papers other than for use by school-children. Type. — Heavy-faced type with bold strokes is always the easiest to read. What are known as 8 and 10 point type (each point representing one-sev- enty-second of an inch) are commonly used in print- ing. Finer type necessitates great strain on the ac- commodation, and requires that the page be held too close to the eye. Coarser type increases ocular labor, and often lengthens the columns and lines. The text of this book is printed in small pica type, which 244 THE EYE. is admirably adapted for comfortable reading. Latin letters are infinitely superior to Gothic, and the Ger- mans are fast discarding their trying type in maga- zines and books for study and scientific reference. Leading between the lines and spacing between the letters are of the greatest importance in securing legibility. There should be about one-tenth of an inch between each line of type. Such a spacing is used on this page. The contrast between leaded and solid type is seen in the following "paragraphs in 8-point type: As a causative factor in the production of headache, eye- strain is by far the most important. Anorexia, dyspepsia, constipation, heart-burn, nausea, repeated attacks of vomiting, etc., represent some of the gastric reflexes. Many cases of obstinate neurasthenia are of ocular origin. Insomnia, night- mare, chorea, and even epilepsy, have often owed their exist- ence and perpetuation to uncorrected eye-strain in some form. The multiformity of the effects of eye-strain can be properly realized only when we understand how vital the function of vision is to every act, emotion, and thought. As a causative factor in the production of headache, eye-strain is by far the most important. Anorexia, dyspepsia, constipation, heart-burn, nausea, repeated attacks of vomiting, etc., represent some of the gastric reflexes. Many cases of obstinate neurasthe- nia are of ocular origin. Insomnia, nightmare, chorea, and even epilepsy, have often owed their existence and perpetuation to uncorrected eye-strain in some form. The multiformity of the effects of eye-strain can be properly realized only when we under- stand how vital the function of vision is to every act, emotion, and thought. The length of the line is of the greatest impor- tance. The old quarto page should be discarded. No line should extend over four and a half inches; and in large books it is infinitely better to divide the page into two or even three short columns with an appropriate blank space between them. The long THE STYLE OF WRITING. 245 lines necessitate extra rotation of the ocular muscles, and are therefore fatiguing to the eye. The lines of this page are about three and a half inches long. The paper used for reading matter should not be glazed nor have a glaring white surface. A dull surface of some slight neutral tint is preferable. It is, of course, necessary to use a good paper and the best ink to secure clear impressions. Paper should be opaque, but this does not necessitate thickness, as some of the most expensive small prayer-books and Bibles are printed on very thin paper. Curved printed surfaces should be avoided. The greatest offenders in regard to unsuitable paper are the two extremes — the newspapers with coarse paper, indistinct impressions, blurred ink, and small type, and the high-class illustrated magazines and books with a highly finished glossy surface to take the popular half-tone plate impressions. The style of writing taught is of less importance than the arrangement of the desk and the position of the pupil. So long as the upright position is maintained and both eyes are equidistant from the paper (i. e. the paper in a central position) it makes very little difference whether vertical or slanting writing is practised. The pupil may be allowed to evolve his own system of penmanship if the essen- tials of position are complied with. However, it is contended that vertical writing is much easier taught and is more legible. The belief that it is less likely to cause astigmatism is based on theory. Overworl< of the Eyes. — The eye is one of the most accommodating organs in the human economy, and under favorable auspices will perform an unlimited 246 THE EYE. amount of work; in consequence, persons frequently demand of this delicate organ an amount of labor never expected of the grosser structures. In fact, it is popularly believed that if the eyes are healthy, read- ing, sewing, and other near work are passive acts, and that the eye is untiring, and never becomes ex- hausted. This is especially true if glasses have been prescribed, for then the patient is more than likely to blame his oculist if the eyes pain when over- worked. Persons whose occupations necessitate much ocular labor should vary their duties with intervals of rest. The clerk who is confined to his desk all day should seek pleasures at night that do not involve ocular labor. In continued reading and sewing, it is well to desist at short intervals and fix the gaze on some distant objects and to close the lids repeatedly. The sensible person so regulates his duties and recreations as to allow his eyes their deserved rest. Artificial Ligliting. — Much of the ocular labor of to-day is performed under artificial illumination. Most persons are so employed during the day that much of their reading, sewing, writing, and other near work is done at night. This is particularly so during the winter months, when the days are short, and there is little inducement to remain out of doors. An ''evening at home" generally implies for both adults and children an evening of ocular labor. The amount of eye- work done to-day is greatly in excess of that of our forefathers. The scarcity of books and newspapers and the insufficient means of illumination, often only by the tallow dip or open fire, discouraged the people of the olden time ARTIFICIAL LIGHTING. 247 from reading at night. To-day artificial illumina- tion is so perfected, and books, magazines, and news- papers are so abundant and cheap, and circulating libraries are so many, that the habit of reading has grown to enormous proportions. In view of all these facts the study of artificial lighting becomes a matter of great interest and im- portance. The main sources of artificial illumina- tion are kerosene, gas, and electricity, all of which when properly employed may be satisfactory. The nearest approach to perfect illumination is that light which most nearly resembles diffuse daylight. Such diffused lighting by artificial means has not been practicable in dwellings, and the best that is gener- ally done is to afford several sources of light near which different members of a family may read with equal ease. The principal questions of importance in artificial illumination are the quantity and quality of the light, its steadiness, the vitiation of the atmosphere by the products of combustion, and the expense. The proper installation of lights in dwellings, school-rooms, stores, and workshops is a matter often neglected. It is common to see a large family gathered about a single gas-burner so placed that those most remote from the light do not get nearly enough illu- mination. This condition is remedied in ordinary dwellings by having as many sources of light as are necessary to allow each reader sufficient illumination without annoying any of the others. In assembly rooms, stores, workshops, etc. these difficulties are not so easily corrected. Besides the expense and necessary vitiation of the 248 THE EYE. atmosphere, the proper arrangement of the lights is often very troublesome. Sometimes the light may be distributed from overhead by reflectors, which also may act as ventilators. In ordinary cluster illumina- tion, even distribution is impossible. Those nearest the light receive the most illumination, but suffer from radiation of heat, and in many portions of the room annoying shadows are cast. If in addition to the central cluster extra lights are used, these may aggravate the annoyances and in some cases shine directly into the eyes of some of the occupants of the room. If, for instance, charts or blackboards are especially illuminated by extra unshaded lights, the writing thereon is read only with the greatest dif- ficulty. In illumination from both sides by single flames, persons who receive light from the right are annoyed by shadows of the hand and head. If the light is only from the left, then some of the occu- pants of the room will be annoyed by shadows cast by their own bodies, and those remote from the sources of illumination will receive too little light, and if the amount of illumination is raised to pre- vent this, those nearest will be dazzled by the in- creased light. Illumination by individual shaded lights for each occupant of the room may be used, but this entails great expense, and unless incandes- cent electric lamps are used there is too much heat given off and the vitiation of the atmosphere is very great. Indirect illumination, by throwing part of the light on suitably colored walls and ceilings from which it is reflected diffusely over the lower part of the room, has been used with success both in this country and IL L UMINA TING- GAS. 249 abroad, and deserves more attention than has been accorded to it by architects and builders. The different illuminants will be discussed sepa- rately in a general way rather than by technical photometric study. Kerosene is the principal illuminant of rural com- munities and among the middle and lower classes. Its cheapness is a great point in its favor. The bril- liant light of the modern lamp when properly shaded by a slightly bluish chimney or shade to absorb an excess of yellow rays is very satisfactory, and, in fact, is preferred by many students and other literary workers to all other kinds of illumination. The principal objections are the heat, the trouble in filling and keeping clean, the danger of explosion and fire if upset, the odor, and the great vitiation of the atmosphere. One, two or three persons working in a large, well-ventilated room may be very comfortable with a coal-oil lamp, but in a large assembly-room in which many lamps are necessary and some are always smoking, vitiation of the atmosphere is great Illuminating-gas has been a great convenience, but also the ruination of many eyes. As usually furn- ished in cities, it has a great excess of yellow rays, which are very injurious. The flame of the old-fash- ioned *' fish-tail '^ burner, blown by every current of air so as to be continually flickering, is a most pernicious form of lighting; yet for years many families have read at night by this means. The vitiation of the atmosphere is very considerable in gas-combustion, and coal-gas is dangerous and more expensive than kerosene, but not so hot and much more convenient. The principal improvements in 2 50 THE EYE. gas-lighting are the Argand burner and the Bunsen burner, heating a patented composition-mantle to incandescence. The Argand burner is very easily controlled, and gives an excellent light, especially when properly shaded. It, however, lacks intensity and is very hot. The incandescent mantle is without doubt the greatest improvement in gas-lighting. It gives a white light resembling daylight, and, under proper adjustment and regulation, of far greater volume (50- 70 candle-power) than any other gas burner, is not so hot, and does not consume as much gas, and hence does not cause such vitiation of the atmosphere. The expense of installation is more than offset by the sav- ing in gas. It is too intensely brilliant to be placed on a level with the eye, unless it is shaded with ground glass, opaque glass, porcelain, or other like material of a neutral tint. If it is desired to light a whole room, the burner should be suspended quite high, and should be unshaded beneath. Holophane globes or reflectors will aid in deflecting most of the rays downward. Electricity is undoubtedly the coming means of artificial illumination. The arc light is unsurpassed for lighting large areas. It is almost colorless, and its spectrum most nearly resembles that of sunlight. It is easily con- trolled, and is becoming more and more inexpensive. Almost any candle-power up to 1000 may be obtained. The arc light is, of course, too dazzling and irregular for ordinary interior lighting, unless very much modi- fied by shading. The incandescent light is now in general use in DIFFERENT ILLUMINATING AGENTS. 251 the cities of this country, and many of the suburban towns have their own electric light plants. It is being furnished cheaper each year, and on account of convenience it is deservedly a most popular form of illumination. It is controlled and lighted very read- ily, and is virtually as portable as a candle and may be used for decorative purposes. It gives a maxi- mum amount of light with a minimum of heat, and this without vitiation of the atmosphere — a most im- portant advantage. The ordinary incandescent light is called 16 candle-power; but in practice its illumin- ating power falls to between 12 and 14 candle-power. This is sufficient only for individual purposes, but the amount of light desired may readily be multiplied to large proportions by the installation of extra lights. The annoying glare of the incandescent coil may be remedied by an opalescent shade. Comparison of the different illuminating agents is given in the following table, taken from the Lo7t- don Journal of Gas-lightings January 18, 1898 : .s S ^s III •6 rt *± u D. rt^3 l-'s S t^-^ s.^ c s cS .S S w E 3 M . «5 = bO 6^ .2 Jilt O.Sx! ^1 '—' CJ .0 Candles. Cu. ft. Calories. Pence (= 2 cents). Coal-gas. Flat flame. 30 14.09 1995 0.768 it Argand. 20 7.06 1000 0.384 . ** Regenerative. III 14.41 2042 0.780 " Incandescent. 50 3-53 500 0.192 Spirit. << 30 3.48 cu. in. 31S 0.240 Petroleum. \\ " burner 30 6.57 cu.in. 960 0.264 <( Incandescent. 40 3.05 cu. in. 550 0.120 Acetylene. 60 1.27 cu. ft. 534 0.264 Electricity. Incandescent. 16 48 Watts 41.4 0.348 (( Arc. 600 258 Watts 222 1.860 252 THE EYE. Acetylene produces a brilliant and in fact dazzling white light, and on account of the small amount con- sumed it is not expensive and there is a small amount of effete materials of combustion. It is, however, very dangerous and liable to explode, and is chiefly used in bicycle and carriage lamps. The danger of explosion begins when the mixture of acetylene with air is at the proportion of i to 26, and it ends at i to 4. Prismatic Devices. — In older school-houses that for financial reasons cannot be abandoned, and in office- FlG. 61. — A plate of glass prisms. and store-buildings where land is so valuable that the buildings must be high and contain many inside rooms insufficiently lighted, the problem of lighting is a perplexing one. The disadvantages of using the eyes continually in an artificial light, the heat and vitiation of the atmosphere, and the expense have all been considered, and need no further discussion here. Any plan that will avoid or that will even partly overcome these difficulties should be earnestly advo- cated. Within the last few years several manufacturers have placed on the market plates of glass which are PRISMATIC DEVICES. 253 SO constructed that they contain a combination of prisms (Fig. 6i) which will bend rays of light from overhead and diffuse them at any angle. Sometimes Fig. 62. — An improperly lighted room on a narrow street. curved surfaces are incorporated with the prisms. By these prismatic plates the insufficient perpen- FlG. 63. — The same showing improvement in lighting by prismatic devices. dicular light of a deep light-well or of a narrow street lined with high buildings may be so refracted that it may be used to illuminate the darkest inte- 254 ^^^ ^^^• riors (Figs. 62 and 63). The prisms may be inserted in ornamental window panes or placed in the form of canopies inclined a few degrees from the ver- tical; or in cases of cellars and basements they may be used in the form of mosaic tiling and be assisted by a second interior screen. These prisms are inex- pensive and ornamental, and are soon paid for in the saving of gas or electricity, besides furnishing illumination infinitely more healthful to vision. A similar arrangement of prisms is also utilized in glass globes, called holophanes, for gas, oil, or incan- descent lights suspended overhead. These globes deflect most of the rays of light downward. The necessary hygienic precautions in reading include the selection when possible of large type, sufficiently spaced, unglazed paper, and short columns. These requisites, of course, do not apply to cheap newspapers, but may be enforced in maga- zines and books. Sufficient illumination is equally necessary, and of no less importance is the posi- tion of the reader, the position of the book, and the relation to the source of the illumination. The posi- tion of the reader should always be upright, leaning slightly backward, with the head erect, and the book held nearly on a level with the eyes, or if it is a heavy volume it may be set in a portable and adjust- able book-rest or placed on a table or desk in such position that the top and bottom of the page will be equidistant from the eye. The closer objects are held to the eye the more muscular and accommodative strain is necessitated in near work. Unfortunately, the common tendency is to read and sew at close range, even when not necessary for clear vision, NECESSARY PRECAUTIONS IN READING. 255 The proper reading distance is about fourteen inches from the eye; but no type should be used that is not clearly legible at twenty inches. Highly near-sighted persons often hold their reading-mat- ter very close to the eye, and, while reading at their far-point without the aid of accommodation, to secure binocular vision they put such tension on their muscles of convergence that serious results may fol- low. Fatigue of the ocular muscles often produces as uncomfortable symptoms as uncorrected ame- tropia. The head should be held erect in reading because in this position there is less liability to ocular conges- tion. The book should be held nearly on a level with the eyes. Continued downward rotation of the eyes is very fatiguing, and there is an inclination to stoop the shoulders before many minutes. Ultimately round-shoulders and contracted chest are produced. The light should be on a level with the top of the head or above the head, and should illuminate over the left shoulder. When several persons are seated around a table or a long desk, and by unalterable architectural reasons all cannot secure the most advantageous position in relation to the light, the use of eye-shades is often of great help. Reading in a recumbent position is a pernicious habit, and is particularly dangerous during conva- lescence from illness or when physically tired. If there is fatigue or a tendency to drowsiness all close work should be suspended, for in this condition accommo- dation and convergence are only effected by continual exercise of will-power, and much nervous energy is 256 THE EYE. lost. When a person is tired or drowsy there is a constant tendency for accommodation and conver- gence to relax; instead of these acts being automatic, there is distinct consciousness of an effort to maintain them. In fact, when one is distinctly sleepy, instead of the normal muscle-balance, there is sometimes actual divergence. In the recumbent position there is extraordinary strain on the muscles of downward rotation, besides a difficulty in adjusting the book for proper illumina- tion. Again, the head is often so bent as to encour- age ocular congestion. If one must read in the recumbent position, the book should be placed against a pillow where it will be well illuminated, and the reader should lie on the side with his face opposite to the page at a comfortable reading distance. Constant looking upward is quite as fatiguing as reading in the recumbent position, as any one will bear witness who has gazed for a long time at the paint- ings in some of the large Continental art galleries. There is a peculiar affection of the ocular muscles, known as " miners' nystagmus," which is caused by the constant upward gaze while at work in the supine position in coal-mines. In this condition the sta- bility of the ocular muscles is impaired, and there is constant oscillation of the eyes. Reading in cars or carriages is injurious to the eyes. Because of the constant jolting, the distance be- tween the type and eye is continually changing, neces- sitating frequent and abrupt accommodative adjust- ments. Besides this fault, there is often very poor illu- mination in the conveyances. However, at the present day the better class of railroads have improved these THE EFFECTS OF SMOKING AND DRINKING. 25/ conditions; there is sufficient lighting, and by mak- ing better roadbeds and furnishing better balanced cars with more numerous springs, they have reduced the jolting to a minimum. In some of the modern cars with incandescent lights for each section, read- ing is not at all uncomfortable. If reading in jolting cars is absolutely necessary, it is a good plan to use a card to be placed under each line, moving it down the page as the reading progresses. Sewing and embroidery require the most trying ocular labor and the best conditions of illumination. When possible, all such work should be avoided at night, and working on black goods by artificial light should be absolutely forbidden. Engravers need not be told the necessity of bright daylight, as they soon find any other illumination incompatible with fine workmanship. They often need enlightenment, however, on the necessity of resting their eyes at frequent intervals during their working-hours. All persons doing fine eye-work should be accurately fitted with glasses if they are at all ametropic. The habit of wearing veils is likely responsible for some deterioration of vision, particularly if they are very thick or dotted. These articles are often necessary to protect the face, to keep the hair smooth, or to maintain headgear in position. In such cases, a thin veil with a very large mesh will answer all these purposes without interfering with vision. The effects of smoking and drinking on the eyes are often exaggerated. Of course, if there is such excess practised that the whole system is affected, the eyes will participate in the resultant morbid processes. Again, in some persons there is a special idiosyncrasy 17 258 THE EYE. to alcohol and tobacco, and often in cases of partial blindness apparently due to what is known as toxic amblyopia, the amounts of tobacco and stimulants used have not been large, yet when these sub- stances have been discontinued vision has been re- stored. Such patients should, of course, give up forever both habits. A particular danger of tobacco- smoke is its irritating action on the conjunctiva, par- ticularly when the smoking is done indoors while read- ing. The smoke curls about the face and enters the eyes, causing great irritation and blurring of vision. Moving pictures have been so much improved that, if the spectator is wearing the proper correcting lenses, the injury to the eyes by attendance in mod- eration to the picture-theatres is almost neglible. The deleterious effects of improper ventilation are much more to be feared. Relation of the Eyes to the General Health. — It is a great mistake to consider the visual apparatus as a separate organization. It is intimately connected with the whole human economy. If there is a defi- cient blood-supply or nervous exhaustion or perver- sion, if the secretions are abnormal, in fact, if there is any serious functional or organic change in the body, the eyes may participate in the evil conse- quences; and in the same way visual defects may in- fluence the whole constitution. Those measures and modes of life which are conducive to general health and vigor will be beneficial in maintaining ocular health and vitality. Persons who seek to preserve their vision all through life must not only observe the laws of ocular hygiene, but also those of general phys- ical and mental hygiene, such as are set forth in the other chapters of this book. SPECTACLES AND EYE-GLASSES. 259 SPECTACLES AND EYE=GLASSES. The invention of spectacles has been attributed to two Italians, Alexander da Spina and his contem- porary, Salvinus Armatus, and to Roger Bacon, all of whom lived in the thirteenth century. On the tomb- stone of Armatus is said to be inscribed, "The In- ventor of Spectacles." From other sources it is con- tended that spectacles were introduced into Europe through the works of Alhazan, a Saracen, who died in 1038 A. D. It is thought, however, that both concave and convex lenses were used by the Chinese long before this. Seneca and Pliny seem to be famil- iar with some of the properties of lenses, and there is a legend that Emperor Nero was near-sighted and used a concave precious stone (emerald) to assist his distant vision. It is, however, only in the latter half of the nineteenth century that the wearing of glasses has become universal, and that the various mechan- ical improvements leading up to the present high standard of excellence have been made. Fitting glasses upon scientific principles was never at all gen- erally adopted until the labors of Bonders and Snellen had evolved a rational method of examining defec- tive eyes and prescribing correcting lenses. Before their time all this was largely a matter of guess-work, often left to spectacle-vendors ; and simple convex and concave spherical lenses with large increments of strength were used. Cylinders were not made. The province of the optician is solely to grind and fit glasses. There is a class of persons call- ing themselves "scientific opticians," "refracting opticians," " ophthalmists," and the like, who, with- out even serving the apprenticeship of a skilled opti^ 26o THE EYE. cian, without the slightest medical training, and with very little or no mechanical knowlege, undertake to prescribe glasses as well as to sell them. They adver- tise "eyes examined free," and sometimes rapidly travel from town to town calling themselves "doctor" or ' ' professor. " It is hardly necessary to reiterate that it is dangerous to intrust the care of such delicate and intricate organs as the eyes to a non-medical person who, working without a fee, has only an interest in the sale of glasses, which, whether needed or not, proper or improper, may be urged on the unsuspect- ing patient. In no case is an optician the proper person to prescribe glasses. This is the business of the oculist, who is an educated physician, and has had long experience in medical colleges, clinics, and hospitals, and who is devoting his life to the study of his profession. He alone is capable of compre- hending the influence of the general systemic condi- tion on the eyes, and of defective eyes on constitu- tional disturbances. Often glasses are prescribed for definite therapeutic purposes other than improvement in vision. The optician is unacquainted with the minute anatomy and physiology of the eye and its physical and psychical relations with the whole organ- ism. He is not skilled in the broad science of medi- cine, of which ophthalmology is only a small part. The true optician has no pretensions other than the skilful grinding and adjustment of lenses. To be a competent workman he also devotes his life in con- stant endeavor to improve the mechanical construc- tion of his products, making eye-glasses and spectacles more sightly and comfortable. Too great stress cannot be laid on the importance of a good optician. The SPECTACLE-LENSES, 26 1 results of all the careful work of an oculist may be set aside by careless and incompetent manufacture and fitting of glasses. It is a safe rule to patronize only those opticians who do not attempt to examine eyes, but confine themselves strictly to grinding and fitting glasses — in other words, purely ' ' prescription special- ists." Such men may charge more for their material and work than the prices advertised by *' refracting opticians," but the worth is in the construction and fitting, and such articles will be cheaper ultimately. Besides, the patient who is ignorant of the proper charge need not fear imposition, such as is often practised by "refracting opticians." Reliable opti- cians are sustained only by the recommendation of prominent oculists, and must act honorably or their support will soon be withdrawn. As a general rule, spectacles are preferable to eye-glasses, and should be used when there is much astigmatism, or when the nose is not properly shaped for the correct adjustment of eye-glasses. The objec- tions urged against spectacles are based on esthetic grounds and upon the uncomfortable pressure they may make on the nose and behind the ears. A well- fitted pair of gold frameless spectacles is infinitely neater looking than eye-glasses pulled out of shape by a cord or chain hanging over the ears and face. If heavy frames are ordered and the spectacles hurt the ears or nose, they are not fitted properly, and the optician should be consulted immediately. Spectacle-lenses are made of clear flint or crown glass. There is no therapeutic virtue or extra dura- bility in the so-called and much advertised "pebble glasses," "rock-crystal glasses," etc. All respectable 262 THE EYE. opticians use for the purpose of grinding lenses the best glass that they can buy. The cost of the glass is small, and they could not afford to waste skilled and valuable labor on poor material. Spectacle-frames are made of gold, steel, silver, and aluminum. The best and most serviceable material is 14-karat gold. It has superior qualities of temper, adaptability to shaping, and durability, and should be used when possible. Ultimately 14- karat gold frames will prove the cheapest, but when they are not practicable on account of expense, the next choice is lo-karat gold or gold filled. Although steel may rust, it is preferable to silver or aluminum on account of its superior hardness and temper. Rubber and shell spectacles are light, but brittle and very difficult to center and adjust. Contrary to popular idea, within certain limits, the heavier the bridge and temple-pieces of spectacles the more comfortable they are. Heavy temples are rigid and keep their shape better, as they stay on the face by their weight, and fit the face, nose, and ears. Such frames do not cut the ears or groove the nose, whereas light-weight frames have no rigidity, cannot be properly shaped, and maintain their position by pulling from the nose to the ears, which is not only annoying, but necessitates constant adjustment. The ideal frames are what are known in the trade as 7985^ (rimless) and 718^ (rimmed) 14-karat gold spec- tacles. Fitting of Spectacles. — It is important that the bridge or nose-piece should be in accurate apposi- tion to the nose, but not deeply indenting it. It should be round on cross section, rather than flat or triangu- THE TEMPLE-PIECES. 263 lar with sharp edges. In .subsequent adjustment the original fitting of the bridge should never be disturbed. The temple-pieces, or "bows," should be curved to set behind the ears for constant wear, but may be Fk;. 64. — Spectacles properly adjusted. straight when the spectacles are used only for close work. They should extend in a direct line from the Fig. 65. — Improperly fitted spectacles. hinges on the outer lens-attachment to the top of the ears. The curve at the top of the ear should be sharp, and the temple-pieces should conform to the shape of 264 THE EYE. the back of the ear (Fig. 64). The typical careless fitting is shown in Fig. 65. The bows should be shaped to the face and in accurate apposition, but not grooving the skin of the temple, thus preventing movement in walking, running, etc. The lenses must be of such size and shape that the wearer does not see over or under them, and they Fig. 66. — Properly centered lenses. must be properly centered and be at equal distance from the eyes (Fig. 66). Improper centering and un- equal distance from the eyes (Fig. 67) often produce prismatic and other effects so injurious as to offset any optic assistance afforded by the glasses, and par- FlG. 67. — Improperly centered lenses. ticularly is this the case in high-power lenses. Lenses should be ground dull on the edges. Polished edges not only cause annoying reflections, but are much more conspicuous. Circular lenses have recently become popular. They should be securely fixed in the frames ; otherwise there is a great likelihood of an astigmatic lens being turned from its proper axis. This will produce most CARE OF SPECTACLES. 265 annoying eye-strain. Again, the upper part of a circular lens is likely to touch the eyebrows or fore- head and soil the glass. lyarge irregularly shaped lenses with flattened tops or drop-oval lenses are preferable to round lenses in nearly every instance. Position of Spectacles. — The upper edges of the lenses should be slightly inclined forward, as most of the time the eyes are directed downward, and in the inclined position the axis of vision will strike the surface of the lens at a right angle, and so avoid reflection. In glasses for near work only the inclina- tion may be made greater. To secure the proper optic assistance from lenses, they should be worn as close to the eyes as possible, and in cases in which very strong lenses are worn interfering eyelashes may be trimmed at short inter- vals without noticeably altering their texture. The periscopic or toric lenses are of value in such cases. Concave lenses diminish in refractive power as they are moved from the eye, while the reverse is true of convex lenses. This explains why old persons who have worn the same pair of convex lenses for reading during many years, gradually push them further and further away from the eyes. Care of Spectacles. — In taking off" spectacles both hands should be used in such a way that the temple- pieces are not pulled widely apart, or otherwise strained so as to wrench, bend, or loosen the attach- ments. Some persons simply pull their spectacles over the ears and weaken the tension and destroy the shape of the bows. In putting on spectacles, the lenses should not be crushed against the eyelashes and soiled. The bridge should be placed one-third down the nose, grasping the temple-pieces near the 266 THE EYE. ear-curve between the thumb and first two fingers. The ear-curve should then be bent over the top of the ears without dragging the lenses any closer to the eyes; the frame should be pushed into position, and, lastly, the temple-pieces should be pressed down upon the tops of the ears. Spectacles should be folded as little as possible, to keep the hinges and attachments stiff. Instead of putting them in a case at night on retiring, they should be left unfolded and resting on the edges of the lenses upon a shelf, mantle, bureau, or some other article of furniture. I^enses should never be laid on their face, but always on edge. If cleansed with improper material or placed face down they are liable to become soiled or scratched. Should the latter occur, the only remedy is repolishing or renewal. Glasses not perfectly clear and clean not only inter- fere with vision, but also cause unnecessary strain and irritation. Lenses should be cleansed several times daily. For this purpose a clean unstarched cotton or linen handkerchief may be used. Chamois, leather, tissue paper, silk, or woollen material, etc., may scratch the surfaces. To remove all obscurities (except in bifocal glasses) the lenses may be cleansed with ammoniated water once or twice daily. In cleansing, the frame should be firmly grasped at the outer edge, close up to the lens, near the hinge, with the thumb and forefinger of the left hand, and not by the bridge. The frame of the lens being cleaned, and not the opposite one, should be held. In cleaning rimless eye-glasses, great care must be exercised not to bend or change the tension of the spring. Reading-spectacles, which are to be put on and BIFOCAL LENSES. 267 taken off constantly, are sometimes more conveni- ently made with straight temple-pieces, particularly in women, on account of the abundance of hair about the temples. Children and persons engaged in occu- pations in which the lenses may be exposed to vio- lence should wear spectacles with rims. Eye-glasses, or " pince-nez," may be used by adults when the lenses are not too heavy or when there is little or no astigmatism, provided the bridge and sides of nose are adapted for them. The new highly-tempered and thin spring, and the modern nose-piece or guards with adjustable arms or offsets permit many more persons to be accurately fitted in eye-glasses than previously. But even when properly fitted, eye-glasses may not be put on in the same posi- tion or place twice in succession, and they are easily bent, losing their exact position before the eye, which by changing the axis of a cylindric lens, particularly in high astigmatism, may greatly lessen the optical improvement. The oculist may have fitted the glasses accurately after the most careful tests, and yet have his results unsatisfactory on account of the fool- ish pride of a patient who insists on wearing eye- glasses when spectacles alone will give relief. Eyeglasses are more conveniently carried about, and need not be folded in a case, and may be hung on a hook on the vest or waist. They may have rims or not, according to the liability to breakage or to the taste of the wearer. The new so-called Oxford eye- glasses are quite heavy and difficult to adjust. Made in precious metals these are really to be classed as expensive lorgnons, and so used. Bifocal Lenses. — Persons past middle life with defective eyes require a separate pair of glasses both 268 THE EYE. for reading and for distance. The reading lenses cause a blurring of vision at a distance, while the distance lenses are insufficient for reading, and the greater the age the greater is the difference between the lenses for far and near vision. In such cases, in- stead of two pairs of glasses to be changed according to the visual needs, bifocal lenses may be used (Fig. 68). The improved form, with a reduced additional convex segment, cemented on the distance lens, is far more satisfactory than the old split Franklin bifocals. The lower segment should be about seven-eighths of an inch wide and one-half inch high; the upper edge more curved than the lower. If the occupation of the patient subjects him to high degrees of heat or steam, the lower segment should be inserted into a Distance Reading Fig. 68.— Bifocal lens. groove in the bottom of the distance lens and placed in rimmed vSpectacles or eye-glasses instead of being cemented on with Canada balsam. The two lenses may also be ground on one piece of glass. Recent and satisfactory types are the fused bifocal lens, and the one-piece bifocal, with both the distance and reading curves ground on one lens. There is much foolish prejudice against wear- ing bifocal lenses. Although it requires some little time to become accustomed to them, bifocal glasses PANTOSCOPIC SPECTACLES. 269 ultimately give far greater satisfaction, and are more convenient than two different pairs of glasses. The patients must be warned about the danger of making a mistake in going up or down the stairs, getting on and off cars, etc., until they have become accus- tomed to the prismatic displacement occasioned. Bifocal lenses need the greatest care to keep them from getting out of adjustment. More than others they demand absolute precision of position. Any imperfection in the cementing of bifocal segments should be remedied at once. The Canada balsam used is sometimes disturbed by the heat and moisture of the face, and becomes opalescent, interfering with vision. If this occurs, the lenses should at once be returned to the optician for repairing. Trifocals have been used by bookkeepers, musi- cians, and other persons who are compelled to use their eyes alternately at the reading distance and at a distance just beyond, as in copying, reading music, etc. Such lenses must be too large to be comfortable, and then are unsatisfactory. It is better to have a separate pair of bookkeepers' or musicians' glasses adapted to a focus of from twenty to twenty-five inches. Fig. 69. — Half-hook fronts for reading. Pantoscopic; spectacles is the name sometimes given to those in which only one-half of a lens is used, allowing the wearer to look over them at dis- tant objects. They are convenient for persons who need only a reading-glass, or they may be employed as hook fronts over distance lenses (Fig. 69), 2/0 • THE EYE. After cataract-extraction or for persons with one eye reversible frames may be used, the lens in one side being used for distance vision, while that on the other is employed in reading. However, a bifocal lens is preferable in such cases. Lorgnettes (lorgnons) and monocles may be used occasionally, but should not be employed constantly as substitutes for spectacles or eye-glasses. The same optic correction necessary in the distance spectacles or eye-glasses must be used in the lorgnette, and the lenses should only be fitted by an oculist. There is a foolish idea that a telescopic or magnifying lens producing an effect somewhat like opera-glasses may be inserted in a lorgnette. Such optic aid cannot be obtained without a dioptric system of at least two lenses. Although persons with nearly normal vision may think at first glance that they see better with a low-power concave lens, the use of such correction when not indicated by myopia causes extra eye-strain. A person with perfect eyes will derive no advantage at distance with a lens in lorgnettes, and persons with faulty vision cannot be made to see better with lorg- nette lenses than with their proper correction worn in spectacles or eye-glasses. Lorgnettes are also used by elderly women for carrying reading-glasses, and bifocal glasses are also used in this manner on the street, in church, at the opera, etc. If the patient has very much astigmatism or needs a high-power lens, the lor^ettes must be carefully fitted and the lenses accurately centered, and they should always be held exactly before the center of the pupils and in a straight position. Tinted glasses should seldom be ordered for con- stant use, but may be temporarily prescribed in in- THE PREJUDICE AGAINST WEARING GLASSES. 27 1 flammatory conditions, during mydriasis, for use at the seashore, etc. The habit of wearing tinted glasses is difficult to overcome. Persistent dread of light (photophobia) is usually due to uncorrected or im- properly corrected ametropia. It is a well-known fact that the constant use of tinted glasses is most employed in countries where the importance of cor- recting eye-strain even in comparatively low defects is not recognized. Wlien tinted glasses are indi- cated, London-smoke plane lenses may be used, and if necessary worn over the ordinary spectacles or eye- glasses and taken off indoors. Coquilles should be avoided, as they generally have some spheric or cylin- dric effect on an irregular surface. For automobiling, sailing, golf, and other sports in the open sunlight, true amber, amethyst-tinted, or the Crookes lenses are often of advantage. The large toric type is valuable here. Before leaving the oculist's care the patient should return with the glasses for examination of the adjust- ment and verification of the lenses by neutralization. Both spectacles and eye-glasses may feel uncomfort- able for the first few days. Tender skin may be bathed with witch-hazel, and hardened by applications of alcohol, cologne-water, alum-water, etc. Frequent visits to the optician for readjustment are necessary, and for this service the best opticians make no charge to their regular customers. Glasses should never be worn when decentered or otherwise out of shape. The good effects of many careful examinations of re- fraction have been spoiled by maladjusted and decen- tered lenses. The prejudice against wearing glasses is happily diminishing and disappearing in most American com- 2^2 THE EYE. munities. Carefully prescribed and correctly adjusted lenses constitute one of the crreatest boons to human- ity, and when they are needed nothing else will take their place. Headaches and other asthenopic symp- toms will continue until the necessary optic correc- tion is worn. It is not uncommon to see people, who have been advised of the necessity of wearing glasses, dose themselves with headache-powders, antibilious pills, nerve-tonics, etc. ad iiauseam^ rather than accept the proper means of relief. Generally this is due to vanity of personal appearance ; but occasionally it arises from the belief that oculists invariably put glasses on all their patients, or that if one starts to wear glasses the eyes will be so weakened that he will never be able to leave off wearing them. Explanation of the frequency with which glasses are worn in the present day is often asked of physi- cians and oculists. The chief reason is doubtless the excessive demand of modern life on the eyes. Schools, newspapers, magazines, books, and free libraries have greatly multiplied in the last few decades. Artificial illumination has been so perfected that every encouragement is offered for reading, sew- ing, and other near work at night. Another reason is that formerly the importance of eye-strain in caus- ing inflamed lids, habitual headache, and other more remote reflexes was not recognized. Then the advice of an oculist was sought only when vision was defective, while to-day a large number of an oculist's patients are slightly far-sighted or astigmatic and have excellent vision, but complain of reflex asthenopic symptoms, the most common of which is headache. Again, much of the modern science of ophthalmology INITIAL DISCOMFORT WITH GLASSES. 273 and the refinements in the grinding of lenses and fitting of spectacles and eye-glasses by opticians are of very recent development. The final reason, and not the least important, is that an ancient senseless prejudice has been permanently overcome. When glasses are indicated they are almost as necessary as proper rest, and the longer they are withheld the more serious will be the consequence. As to the frequent inability to discontinue their use later, if this is the case, no better proof of the wisdom of pre- scribing them can be offered. On the other hand, it not infrequently happens that by tiding over a threat- ened nervous breakdown during a temporary state of ill-health, the use of glasses allows the system to recuperate to such a point that they may then be discarded, when otherwise either the health might have been irreparably ruined or the ultimate resort to glasses become permanent. The proper glasses do not always suit at first, and the oculist is often called upon for an explana- tion. In far-sightedness and astigmatism the accom- modation is so hypertrophied and cramped by long years of strain that the full correction found under mydriasis is rejected when the effects of the drops pass off". In such cases the proper lenses may blur distant vision, and the patient may even see much better at a distance without them. However, the glasses should be persisted with, in the same manner that a disagreeable medical treatment is pursued, until the accommodation relaxes, when all the objec- tions disappear and the asthenopic symptoms are relieved. If patients succumb to their early difficulties with glasses and only wear them spasmodically, the initial 18 274 '^^^ ^^■^• discomfort is only prolonged. If the glasses become absolutely unbearable, the oculist's advice should be sought before they are discarded. The spasm of accommodation is only one of many reasons for the discomfort of new lenses. Often the apparent change in the size of objects and the false estimation of dis- tance are sources of perplexity; but these also dis- appear in a few days. In such cases it is common to hear such complaints as "the glasses make me dizzy," "everything seems crooked," "the floor seems too close to me," "the glasses make me ner- vous," etc. The reflections from the glass and the irritation by contact with the skin are other troubles which soon disappear. Again, persons who have never worn glasses will turn their eyes instead of slightly turn- ing their heads when looking sideways and so bring about confusion of vision. Some patients, during their early period of annoyance, happening to pick up a pair of weaker convex or stronger concave glasses, as the case may be, belonging to an acquaint- ance, and, finding that for the moment vision appears plainer, may foolishly believe that their oculist has given them the wrong optic correction. It is by reason of this same false momentary judgment in trying lenses without the use of mydriatics that patients who select glasses in an optician's store are so often given a wrong correction. Finally, certain near-sighted adults who have never worn a distant correction, although acknowl- edging the visual improvement afforded by the proper glasses, yet have become so contented with the gen- eral haze before their e3^es, and are able to read so easily with their naked eyes, that they refuse to use ARTIFICIAL EYES. 275 glasses constantly, although employing lorgnettes and eye-glasses occasionally at the theatre, etc. Such persons should be informed of the danger of pro- gressive myopia when the proper lenses are not worn, particularly in prolonged close work (see page 216). Glasses should be changed at frequent inter- vals, particularly for children or adults who are rapidly changing in stature. A great difference in refraction may occur after profound shock, protracted illness, confinement, and other similar depressing conditions. A good rule to follow is to seek the advice of an ocu- list whenever any of the original asthenopic symp- toms recur or when there is disturbance of either far or near vision; and in the absence of any subjective indications of change, it is not an unwise procedure to consult an oculist at least every three years, and so forestall any disagreeable symptoms. The necessity of changing glasses to correct the constantly changing refraction is not generally known, and it is not un- common to find educated persons wearing one pair of glasses for many years, and often aged persons use the same reading-glasses over long periods, gradually pushing them down the nose as the presbyopia increases. Artificial Eyes. — In persons so unfortunate as to lose an eye or who have had enucleation performed on account of disfigurement, an artificial eye offers a good substitute and is often a decided cosmetic advantage. Artificial eyes are made of every size and variety. The requisites in selection are the proper color of the whitish-blue sclera, which differs in shade from that in the pale blonde to the dark bru- nette, the color of the iris, and the normal size of the 2/6 THE EYE. pupil. Artificial eyes are generally made of porcelain and are mere shells, although recently hollow glass and metal bulbs have been used to fill out the orbit. The amount of tissue and muscle left in an orbit after enucleation of an eyeball determines the motility of the stump. In some orbits there is such free move- ment of the stump over which the shell fits that it follows exactly the ordinary movements of the sound eye and is only discoverable in positions of extreme rotation. This is particularly the case when abscission, evisceration, implantation, or Mules' s operation has been practised. An artificial eye may be first worn after a lapse of two or three weeks from the date of operation if all inflammation has subsided. Early application of an artificial eye is advisable to prevent absorption of orbital fat. The orbit is very tolerant of foreign bodies. However, to accustom the tissues thoroughly to an artificial eye, it should not be worn more than a few hours at a time for the first few days. To insert an artificial eye, it is lubricated and the broad outer end slipped under the upper lid, which is slightly raised; the lower lid is then drawn down- ward and the patient is told to look down, when the eye is gently manipulated into place. Irritation of the stump by an artificial eye has led to sympathetic involvement of its fellow, and must be guarded against. An artificial eye should be taken out at night and washed, and placed where it will not un- dergo a marked change of temperature. It must be replaced every two or three years, as it loses its luster and becomes noticeably different from the sound organ. HYGIENE OF THE BRAIN AND NERVOUS SYSTEM* By J. W. COURTNEY, M. D., OF BOSTON, Physician for Diseases of the Nervous System, Boston City Hospital. GENERAL PRINCIPLES. Nervous tissue is one of the most delicate and highly organized in the body, and possesses the least reparative power. On this account Nature has pro- vided it, for the most part, with appropriate bony protection — the cranium in the case of the brain, and the spinal column in that of the cord — against external violence. For the nerves which enter and leave the brain and cord through apertures in their bony coverings she has, however, generally speak- ing, made no such wise provision, but has endeavored to compensate for her shortcoming by endowing them with a much greater power for repair than either the brain or cord. The general construction and mechanism of the central nervous system with its peripheral ap- pendages, the nerves, are analogous in all essential details to a great telegraphic system. By the nerves, which ramify in all directions like a lot of telegraph wires, the most distant parts of the body are brought into communication first with the spinal cord and then, if need be, with the central terminal 277 278 THE BRAIN AND NERVOUS SYSTEM. station, the brain, where certain messages are re- ceived and interpreted by our consciousness, and others sent down through the appropriate nerves lying in the great cables (so to speak) of the brain and cord, to be switched ofif at the proper levels to their destinations. When we consider that it is upon the perfect integrity of the fine adjustment of this delicate and intricate organization that the healthy functional activity of every other tissue in the body, even to that of the most insignificant secreting gland, de- pends, we are in a position to estimate the extent to which our physical as well as mental well-being is under its control. To increase the marvel we have only to learn that Nature has seen fit to make what have been termed the master tissues of the body, the brain and spinal cord, dependent for their own vitality upon a blood-supply which comes to them through arteries which, for the most part, are what are called end-arteries, or arteries which have no communication with one another; a plan which means almost inevitable death to these parts when the arteries break down or become occluded. With this brief statement of the paramount im- portance of the role played by the brain and nervous system in the carrying on of vital functions, we are in a better position to enter upon a consideration of the measures which may be adapted for the main- tenance of these organs in a healthy state. Influences of Heredity, Education, and Environ- ment. — At the present day we frequently hear the term "born degenerate" used to designate some unfortunate who happens to be the possessor of a HEREDITY AND ENVIRONMENT. 279 liigli-arched palate, misshapen ears, or an asymmetric skull, and who, under stress of circumstances, be- trays some mental or moral obliquity. The argument is that Nature while inflicting upon this individual outward stigmata of her freakish ness, has been equally unkind in the matter of moral and intellec- tual endowments, and that he, in sinning against well-recognized laws, is simply the victim of his own vicious organism. To argue thus is fallacious in the extreme, for it throws a most unwarrantable burden upon Nature, and leaves absolutely nothing to the ac- count of two factors which are of vast importance in determining the mental, moral, and social status of every individual — namely, education and environ- ment. In proof of this, one has only to seek in the circle of his own acquaintances. This all leads, however, to the matter of heredity and its influence upon a person's nervous and mental welfare. Upon this point may be quoted the following admirable statement of the facts in the case by Dr. James J. Put- nam:^ " Fortunately for the educational outlook, the evidence has begun to accumulate that a morbid in- heritance is not the inevitably crushing and baneful thing that it has been thought. We come into the world, each one a being of limited capacity, but in other respects free to become what circumstances make us, and responsible, to the extent of our capac- ity, for our lot. We bring no ticket-of-leave which stamps us as drunkards or maniacs on probation, but we do bear, in the histories of our ancestors, a certifi- cate that hints by what efforts and by what avoid- ^ The Shattuck lecture — " Not the Disease only, but also the Man." By James J. Putnam, M. D., of Boston. 28o THE BRAIN AND NERVOUS SYSTEM. ances we can make ourselves reasonable successes in our respective lines. There is no original sin, and not even, as it seems to me, original propensity, but only original capacity and original limitation, and even limitation is only another name for latent ca- pacity. ' ' Anyone at all familiar with nervous and mental diseases must at once be struck with the unquestion- able soundness and fairness of Prof. Putnam's point of view. It brings the question of personal equation and responsibility into its proper focus and hints at the happy results which we may confidently expect from a due regard for the laws of hygiene in its broadest sense. Certainly it presents a most striking and stimulating contrast to the pessimistic fatalism of the views previously alluded to. With regard to the brain and nervous system the hygienic problem is a far-reaching one, and if we would attack it at its very source, we must ask our- selves at the outset by what efforts and avoidances we may expect to ensure the unborn child against the dangers which threaten the stability of its mental and nervous organization. This is a question which leads us directly back to the period antedating con- ception. In many unfortunate cases at this time the personality of one or both parents is, on account of alcoholism or other vice, for the time being, in a condition of morbid alteration, the deleterious influ- ence of which may be profound and enduring. But proper care of the mind and body at this time is only the beginning of parental responsibility. From the commencement of pregnancy to its close, and all through the period of lactation, every efibrt should be ADVENT OF THE SCHOOL-GOING AGE. 28 1 made to divert from the mother all possible causes of nervous wear and tear, chief and foremost of which are worry and anxiety. The nervous and mental hygiene of childhood antedating the school-going epoch is comprised in such elementary factors as proper food and clothing, an abundance of sleep, and life in the open air. The advent of the school-going age presents many serious problems, and as it is often at this time that the laws of mental and nervous hygiene suffer the first infringement by which profoundly deleterious results are brought about, the whole subject is deserv- ing of treatment at some length. It is contended by certain authorities that Ameri- can children are sent to school at too early an age and compelled to do an amount of mental labor incompat- ible with the healthy growth of their physical organi- zation. With regard to this it may be stated dogmat- ically at the outset that, so far as children under twelve years of age are concerned, the danger of brain over- work has been unjustly exalted, for, with very few exceptions, their natural inattention and playfulness are their safeguard. Of far greater, in fact, of para- mount importance, as far as nervous and mental welfare is concerned, is the matter of sunlight and pure air in the school-room, and of seats and desks which will not distort the pliant spines and chest- walls of such children, thereby impeding the circula- tion to the important nervous centers upon which the strain of study naturally comes. It is toward matters such as these that parents and educators should be led to turn their serious attention, for with such crying necessities unattended to, the present warfare which is 282 THE BRAIN AND NERVOUS SYSTEM. waging in educational circles over the teaching of matters of tenth-rate importance, notably the food- value of alcohol, is superlatively premature, to say the least. Impure air we know not to be a food but a poison, and a distorted spine in a growing child is more easily acquired than corrected. In regard to the class of children that form the ex- ception to the general rule, a word of precaution is demanded. Such children come under the head of what may be termed the dangerously precocious, and for them the modern overstimulating methods of school-instruction are fraught with dangers not easily overestimated. As a rule they are frail in body and of a decidedly tubercular taint, the activity of their physical powers seeming to be in the inverse ratio to that of their mental. What such children really need is a repression rather than a stimulation of their men- tal faculties. For them the ideal training is one of their muscles and of their vegetative functions, and this they can get only by the freest possible life out of doors. After the age of twelve the question of brain over- work really begins to assume proportions worthy of serious consideration, for it is then that what we may term the fancy-work of education commences. By this is meant that children are launched upon the variegated curricula of the high-school and academy, and are subjected to a process of mental gymnastics sufficiently arduous to strain the powers of an adult, to say nothing of children who are approaching that very important physical crisis, puberty. Puberty and its attendant dangers to mental and nervous health have caused the expression of many PUBERTY AND ITS ATTENDANT DANGERS. 283 extreme views. There is no question that in both sexes (but especially in boys) the psychical effect of puberty often outweighs the physical ; hence we begin to observe the real awakening of the "ego," of the condition of self-consciousness, the proper trend of which means so much for the health of the nervous system. It is a period certainly when nervous and mental aberrations are not uncommon, but are we right in attributing them all, as certain authorities are inclined to do, to brain over- work ? Such a contention seems wholly unjustified except in rare instances. The root of the evil lies largely in the mawkish sentimentality and artificial modesty which possess a large percentage of parents through- out the land, and prevent them from explaining to their children the mental as well as physical sig- nificance of the changes which the latter are destined to undergo at this period. The result is, in the case of the girl, that the establishment of the menses often comes as a mental shock which may prove the last straw in the genesis of a nervous break- down, for which her "studies" have already paved the way. In the boy the reaction is different and fre- quently far more disastrous, for he, finding himself in the possession of a newly-awakened instinct, is often led into habits which may mean little less than abso- lute mental and nervous ruin. This subject is well worthy of the serious attention of every parent and teacher. Much ill-considered treatment of the problem has found its way into text- books of medicine and medical writings in general. This, it seems, arises from an undue exaltation of the importance of the direct physical results. Such 284 THE BR Am AND NERVOUS SYSTEM. teaching is dangerous, for the naturally self-conscious youth is imbued by it with the fear of irreparable bodily injury, self-inflicted. A vicious cycle is estab- lished. He quickly becomes self-analytical, and by autosuggestion succeeds in bringing about actual physical suSering. The primary factor of moment is, however, the implantation of the morbid fear, and unless this is quickly eradicated, the complete nerv- ous undoing of its victim is in time effected by mis- guided medical or lay advisors, or by the criminal insinuations of designing quacks, whose villainous publications are constantly flooding the country. The teaching of practical morality is the key to the problem. The responsibility of the entire matter rests primarily with pairents and teachers; but to judge from the prosperity of the very lowest and most offensive sort of charlatans, and from the large number of persons who, under the scourge of the most pitiable mental anguish, seek the advice of reputable physicians, it would seem that this responsibility, great and significant as it is, rests, in many instances, with appalling lightness. NEURASTHENIA (Nervous Prostration). General Remarks. — In that limited number of cases in the class of children in which brain over- work can, with a reasonable degree of accuracy, be looked upon as the exciting cause of nervous break- down, it may be said of them that they are usually the victims of inherent weaknesses coupled with a total disregard of the most elementary rules of personal hygiene; and the same statement is applicable to col- lege men and women. The condition of nervous NEURASTHENIA. 285 breakdown thus brought about differs in no important characteristics from that which arises from other causes, and as we commonly hear it spoken of as American "nervousness" or "neurasthenia," it will be well to consider all the factors which may be active in its production. To speak of neurasthenia as a condition to which the American people are inherently liable is to neg- lect the facts of statistical evidence. The average American has no more inherent liability to suffer from undue exhaustion of his nervous powers than the representative of any other nation on earth. And yet, through disregard for the ordinary laws of hy- giene, so many victims are added yearly to the num- ber who fall under the evil consequences of an outraged nervous system, that the question of prevention be- comes one of vital importance. To present this side of the subject in its proper light a preliminary study of the causes and results of nervous weakness, or asthenia, will be necessary. Definition. — The term "neurasthenia" may be said to denote a condition of pathologic fatigue of the entire nervous system and also to connote a coexistent condition of morbid nervous irritability. Of its underlying pathology little is definitely known so far as the human subject is concerned, but from the experimental work of Hodge ^ and others on animals, to which reference will be made later, it would seem that we are not altogether justified in speaking of it as a condition without any discoverable pathologic basis. Causation. — The subject of the causation of this ^ Hodge, Journal of Morphology, Boston, 1892. 286 THE BRAIN AND NERVOUS SYSTEM. condition is one of the deepest and most subtle with which the physician has to deal, embracing as it does a consideration of factors that concern not only the hereditary aspect of the individual, but also the edu- cational, the latter term being used in its very broadest sense. These two factors, heredity and education, are the most important elements among what we may term the predisposing agents in the genesis of the morbid state under consideration. As a strong third comes occupation. The prolific inventor, the broker on the stock exchange, and others whose business affairs entail perennial emotional unrest, are found in the majority in the now great army of neurasthenics. School-teaching also seems to be fraught with danger. The question of social position as a predisposing element is often erroneously treated by writers both lay and medical. Neurasthenia is by no means an affection which is confined to the wealthy. On the contrary, it forms about 40 per cent, of the diagnoses entered upon the records of the nervous department of the Boston City Hospital, and the same fact probably holds true as regards the hospitals of other large cities. As already said, the belief that Americans, as a race, are, by virtue of inherent peculiarities, espe- cially liable to nervous breakdown is altogether erro- neous. The error probably arises from the careless classification as Americans of all denizens of this country regardless of origin. The real fact of the matter is that the Semitic race furnishes by far the greatest quota of nervous sufferers. As to the time of life at which the affection most commonly appears, it may be stated, as a general SYMPTOMS OF NEURASTHENIA. 28/ rule, that the period between the second and fifth decades stands preeminent, although cases are not in- frequently met with at both earlier and later periods. On the immediate or exciting causes of neuras- thenia, there is no need of elaborate argumentation. They may be stated categorically in the following order: over-work, whether physical or mental, and prolonged morbid emotional excitement, such as worry, anxiety, vexation, and grief. Symptoms. — If, as has been stated, it is upon the perfect integrity of the fine adjustment of the nervous mechanism that the healthy function of all the other organs of the body depends, and if neurasthenia is to be looked upon not only as a pathologic fatigue of the nervous system, but also as a morbid irritability, we should expect to find in a given case symptomatic evidence both of degraded organic function and of over-reaction to environment. And this is exactly what obtains. The check-rein of the nervous centers being loosed, the bodily functions run riot, and the sufferer presents symptoms of disturbance of diges- tion, circulation, secretion, and of the sexual func- tions. Nor are these all. The strict domain of the nervous system contributes its quota to the morbid complex, and we find the victim also offering symp- toms of disturbed motion and sensation, both com- mon and special, and of perverted intellection. He, or she, is weak and incapable of sustained muscular effort, as is easily shown by the diminishing power of successive hand-grasps, and by the tremulousness which accompanies even the slightest outputs of muscular force. The sensory disturbances are of the most varied 2S8 THE BRAIN AND NERVOUS SYSTEM. type. In many cases there are actual pains in various parts of the extremities and trunk; in others areas of heat or cold are complained of. Especially annoying are the headaches, which are sometimes referred to the top of the skull and sometimes to the base, and when in the latter situation, there is also experienced a feeling as if the head were too heavy for the shoulders, or as if it were being con- stantly pulled back by the neck muscles. Often the spine is tender throughout its entire length, at times exquisitely so. Tender spots are also found in vari- ous regions of the trunk, notably in the region of the breasts and over the stomach, and patients often complain of numbness and pain extending from the elbow along the inner border of the fore- arm into the ring and little fingers, the latter annoy- ance being most commonly experienced on awak- ing in the morning. Not infrequently dull, dragging aches in the extremities take the place of actual pain, and in addition to the aching there will be present curious sensations, ''as though the blood were bub- bling in the veins," or "as though the heart were beating all over the arms or legs. ' ' The disturbances of the special senses are often very marked, one of the earliest being a blurring of the vision on using the eyes for any length of time. This may become so pronounced that the patient is totally unable to perform any labor, such as sewing, reading or writing, which requires steady fixation of vision for any length of time. The auditory annoy- ances usually take the form of adventitious sounds in the ears, such as ringing, buzzing, whistling, singing, roaring, etc., hearing itself never being SYMPTOMS OF NEURASTHENIA. 289 seriously impaired. Disorders of smell are not com- mon, but those of taste are frequently complained of; the sufferer saying that "nothing tastes right," or that there is a bitter or a salty taste in the mouth, without any reference to the taking of food. The disturbances in the intellectual sphere are very strik- ing and often causative of the greatest mental anguish. Finding himself incapable of fixing his attention for any length of time without great physi- cal discomfort, the patient soon begins to fear that he is losing his mind, and this leads him into a habit of introspection which is often most pernicious in its consequences. To the fear of insanity is shortly added a host of other fears, which so limit the capacity for initiation that the patient's friends often have to lend him their aid in the accomplishment of the most commonplace undertakings. He becomes emotional and cannot bear to read of accidents, murders, or sudden deaths from apoplexy or heart disease. His sleep is troubled, and he awakes more tired in the morning than when he went to bed the night before. Often on closing his eyes in bed he has sudden spasmodic jerkings of his legs, or a feel- ing as of falling. Real insomnia does at times occur, but most nervous sufferers very much underestimate the actual amount of sleep obtained. The digestive disturbances are varied, but they most frequently consist in an inability to digest starchy food. Patients complain that everything they eat rests like a great lump of lead in the stomach, and the gas arising from the fermentative processes going on in the stomach often interferes to such a degree with the heart's action that it becomes accel- 19 290 THE BRAIN AND NERVOUS SYSTEM. erated and irregular — " feels as though it turned over at times." Sometimes there is a faintness or "all- goneness" within an hour or so after taking food. The movements of the bowels are capricious, but constipation is more common than diarrhea. As has been stated, the heart's action is frequently interfered with by the digestive troubles, but aside from this all sorts of anomalies of force and rhythm may occur independently and give rise to most intense anxiety. The pulse is often heard in the ear by the patient himself when the head is lying on the pillow, or felt whenever two parts of the body are brought in con- tact. The vasomotor apparatus of the blood-vessels is frequently so irritable that sudden flushings and pallors are common. The secretions are usually more or less generally interfered with, and the patient is often harassed by profuse and annoying sweatings, which may occur either by day or by night and may be general, or confined to the hands, or even to one surface of an extremity. Extreme dryness of the mouth is complained of in certain instances, in others salivation. Frequent micturition is common. Dis- turbances in the sexual sphere often find a prominent place in the morbid train. In women analogous symptoms occur in the same sphere, but with very much greater infrequency. Fortunately, not every case presents all of the morbid conditions at the same time, or at any time; but a large number run nearly through the gamut if they are at all prolonged. This is especially true of those in which introspection plays a prominent part, and these are generally recruited from among the educated classes. With such people a little medical PATHOLOGY OF NEURASTHENIA, 29T knowledge is a dangerous thing. They are morbidly alert for new symptoms, which, owing to the intense power of mind over matter, are not long in presenting themselves, and these they proceed to interpret in a fashion utterly false and illogic. Pathology. — Of the pathologic substratum of neurasthenia little is thus far definitely known, but as we are morally certain that such intense fatigue of the nervous system as is logically assumed to be present in this condition cannot exist without leaving some structural imprint, it may prove interesting to note briefly the results obtained by the finer methods of investigation in animals, whose nervous tissues had, either by electric stimulation or by prolonged normal exercise of function, been brought into the condition of exhaustion. In these experiments the results obtained were always the same and had to do with the nerve-cells. These latter were found to be altered in size and shape, and in their constituent elements; the alteration being in the form of a gen- eral shrinkage, with irregularity of outline of the cell-nucleus and of the protoplasm. The chemic reaction was also altered. A further discovery of interest was that cells recovered after electric stim- ulation, but that recovery was sloWj twenty-four hours' rest scarcely sufiicing to bring it about after five hours' stimulation. The above results of experimental investigation are most interesting and suggestive, and, while we are not warranted in saying absolutely that the same pathology holds good for nervous exhaustion in the human species, it requires no great stretch of the imagination to conceive of similar changes taking 292 THE BRAIN AND NERVOUS SYSTEM. place in this latter condition. The symptomatic aspect of the problem is certainly more than sufficient warrant for such belief. Prognosis. — The question of the duration of the affection is not the least important with regard to it. This, however, depends upon so many and so varied conditions that the outcome of the individual case must be decided on its merits. Recovery up to a certain degree is the rule, though at times it may be complete; but this takes place usually only after a long and discouraging siege which is marked by many relapses. Patients will often lose in a very short period whatever of gain they may have been many weeks in accomplishing. Hardly any of them come out of the conflict unscathed, and though many recover sufficiently to cope with the ordinary duties and trials of life, they are never quite capable of weathering its real storms. Hygienic Treatment. — The subject of treatment proper does not come within the scope of this article, the point at issue being, rather, by what " efforts and avoidances," as Prof Putnam puts it, by adherence to what hygienic laws, in other words, we may pre- vent ourselves, or those confided to our care, from drifting upon the shoals of nervous and mental degra- dation. In this connection, however, too narrow an interpretation must not be put upon the scope of these laws. We are about to deal with matters mental as well as physical, and are therefore constrained, in consid- ering the health of such a metaphysical structure as the mind, for instance, to embrace the moral as well as the physical aspects of the problem. And THE ABUSE OF ALCOHOL. 293 here it may be stated that the hygienic principles to be advocated by no means apply solely to the preven- tion of that single aberration of nervous and mental health which has been described under the term neu- rasthenia. On the contrary, they apply with equal pertinency to a very large number of equally pre- ventable diseases of the brain and nervous system. Every physician whose duties bring him much in contact with the victims of nervous and mental dis- ease will unhesitatingly endorse the statement that the nervous and mental health of a nation is in direct relation to its moral health. The greatest scourges of the nervous system are syphilis and alcohol, and it is a distressing fact that many of the paralytics who go dragging their painful way along toward a prema- ture grave, and that hundreds of other people who, in the very prime of life, meet with absolute annihi- lation of their intellectual faculties, are simply the victims of their own immoderate appetites and un- restrained licentiousness. The Abuse of Alcohol. — The physiologic chemists tell us that alcohol received into the system is there consumed in the same way as starch and sugar, and that the energy yielded by it becomes kinetic in the form of heat — is transformed into muscular strength; further, that it takes the place of other food-ingre- dients in the actual nourishment of the body. These are the facts of physiologic research, of laboratory experimentation, and as such are beyond cavil. Few physicians of experience will deny the great advantage to be derived from alcohol in combating the poison of fevers and in the maintenance of nutri- tion in certain debilitated states ; but neither will 294 ^^-^ BRAIN AND NERVOUS SYSTEM. they be inclined to deny that the kinetic energy stored up in the healthy tissues of a man by the introduction of one or two ounces of alcohol is likely to expend itself in ways detrimental to that individual's future nervous and mental — in fact, his whole physical and moral welfare. Alcohol is certainly a poison for nervous tissues, and when taken constantly into the system, even though the daily amount be small, often produces organic changes. By persons of nervous temperament, so- called, the use of- alcoholic stimulants is especially to be avoided, since the discomfort of the after-depression, even from the use of very small amounts, more than counterbalances the temporary sense of increased ner- vous energy produced. The question of the advisability of the use of tea, coffee, and tobacco allows of a wider range of debate. A cup of coffee in the morning does no harm, and is often conducive to a satisfactory movement of the bowels. The excessive consumption of tea, to which many women of nervous habit are addicted, often to the exclusion of nutritious food, is, however, particu- larly to be deprecated. To the man of weak nerves the use of tobacco will never prove anything but harmful. Of the virulency of the syphilitic poison on the ner- vous system and the subtle w^ay it invades it — often- times years after the primary inoculation — volumes have been written. Let it suffice to repeat here that of the large number, especially of the young and middle-aged, who are yearly stricken with a sudden paralysis of one side, or one extremity, or who, for no other apparent reason than the commonly alleged OVER-WORK, 295 "over- work," sink gradually into the gloom of com- plete dementia, the majority are its victims. The lesson in moral hygiene thus relentlessly taught leads directly to the preaching of the necessity for the early and firm building of character as a nervous and mental safeguard. American parents are neither more indifferent nor careless as regards the mental and moral welfare of their children than people of other coun- tries, although certain pessimistic writers on this sub- ject would have us think the contrary. They do need, however, to have it firmly impressed on their minds that, in a country like ours, where independence is the watchword, this independence cannot with safety be made to apply to their relations with Nature; and, further, that if they would have their children pre- serve their mental and nervous equilibrium in the presence of the appalling vicissitudes of fortune so commonly observed in this country, they must early inculcate such saving principles as fortitude, self- denial, and self-control. OVER=WORK. As the direct, or exciting, cause of nervous and mental breakdown much emphasis has been laid upon over-work, both physical and mental, and this leads to a consideration of the measures which may be taken to avoid it. To formulate rules, however, which will fit every case is clearly impossible, since the whole subject resolves itself into the question of personal limitations. Everyone at all observant of his bodily and mental conditions must be fully cognizant of what Dr. Holmes ^ called the ' ' curve of health. ' ' To 1 Oliver Wendell Holmes, Over the Teacups. 296 THE BRAIN AND NERVOUS SYSTEM. use this author's own words : " It is a mistake to sup- pose that the normal state of health is represented by a straight horizontal line. Independently of the well- known causes which raise or depress the standard of vitality, there seems to be — I think I may venture to say there is — a rhythmic undulation in the flow of the vital force. The ' dynamo ' which furnishes the work- ing powers of consciousness and action has its annual, its monthly, its diurnal waves, even its momentary ripples, in the current it furnishes. There are greater and lesser curves in the movement of every day's life — a series of ascending and descending movements, a periodicity depending upon the very nature of the force at work in the living organism. Thus we have our good seasons and our bad seasons, our good days and our bad days, life climbing and descending in long or short undulations, which I have called the curve of health.'' In this very shrewd observation are contained the elements of a practical and satisfactory working hypothesis. It teaches that everyone should strive to give due heed to the ebb and flow of his vital forces and regulate his periods of activity and rest accordingly. Mental Over-work. — Many persons are either ignorant or unmindful of the fact that intellectual activity has a tangible physiologic substratum, but for proof that it has we need only to recall the pict- ure which someone has drawn for us of a literary man hard at work, with an ice-cap on his head and his feet in a pail of hot water. Physiologists have shown that intellectual activity is always accompanied by cerebral hyperemia ; in MENTAL OVER-WORK. 297 other words, by a marked increase in the amount of blood contained in the vessels of the brain. This being so, we should refrain from bringing about this condition at a time when the blood thus attracted to the brain is urgently needed for the proper functional activity of the bodily processes, notably digestion. As an example of what often results from an infrac- tion of this rule we have need only to look to the large number of cases of stomach and intestinal in- digestion in brain-workers who persist in pursuing their intellectual avocations immediately after eat- ing. It is obvious then that intellectual and diges- tive processes cannot, with any degree of comfort, be called into play at the same time. The morning seems to be the time when the brain, after the repair occasioned by a night's rest, possesses the most "verve," and it is then that the bulk of in- tellectual performance should take place. Almost from the beginning of the day the process of running down goes on, and this running-down process seems to reach its maximum at about four o'clock in the afternoon. It is at this hour certainly that the vital- ity of the nervously weak often reaches its lowest ebb. There is, however, a subsequent increase in vigor, which is derived from taking the evening's meal, but the blood-supply to the brain has already begun to be influenced by the waste products of the active cells. These waste products ultimately accu- mulate faster than they are removed, render cerebral activity more and more difficult, and finally suppress it to such a degree that sleep intervenes. This is the way, then, that Nature, if left to her- self, would regulate the matter of waste and repair, 298 THE BRAIN AND NERVOUS SYSTEM. and it would certainly be of great benefit to brain- workers if they took the hint from her and arranged their periods of mental activity and rest accordingly, even though they did so only to the extent of getting that portion of their brain-rest which is comprised in sleep, during the hours between ten o'clock at night and eight in the morning. With all due respect to opinions to the contrary, the brain-worker requires more sleep than the laboring-man, and he is certainly doing himself an injustice, against which his nervous system will sooner or later rebel, if he attempts to get along with less than eight hours. Every now and then we are treated to an article in some popular magazine which informs us that some favorite author carries on his work at hours, and on the strexigth of an amount of sleep, which set all the laws of Nature at defiance. Whether this perform- ance is exploited with the idea of stimulating the ambitious young man or woman to do likewise or not, is not known, but it certainly does not take much critical acumen to detect in the work of such an author positive evidence of a lack of sustained effort which is greater than can be accounted for on ordinary grounds. At all events the world would be far better off if it were spared much of the material which comes to us in the guise of literature, but is in reality the product of the same sort of cerebration that produces bad dreams and nightmare. Occa- sionally great thoughts will insist on forcing their way into the consciousness during the dead of night, but these occasions are, on the whole, so rare that we may with safety incur the brief loss of sleep which the recording of them on paper entails. Unfortunate examples of the effects of intellectual employment during the normal sleeping-hours are the cases of neurasthenia in editors and reporters employed on morning newspapers. Worry. — The brain is an organ which, under proper training, is capable of performing an immense amount of work, provided only that the work is of a varied character and does not induce a correspond- ing amount of emotional disquietude. The impor- tance of the emotions, especially the depressing emo- tions such as grief, anxiety, and worry, as factors in brain exhaustion, cannot easily be overestimated. It is a theme, however, which has been harped upon so much by writers on nervous diseases that the country at large seems at last to be awakening to the fact that some united effort should be made to obtain emancipation from at least one of the morbid list, and in consequence we now have the ''Don't Worry " Society, among w^hose members are many hundreds of brain-workers. Such a popular move- ment is certainly commendable and will no doubt lead to much beneficial result. The old saying that it is not work but worry that kills is particularly rele- vant with respect to brain-work. A mere fit of low spirits, for the time being may cripple a man in the use of his intellectual faculties, but circumstances still tend to influence him, and he can review his position, even though he does so gloomily. His sav- ing clause lies also in the fact that the turn of events and the moderating influence of time produce restora- tion of physiologic and psychologic equilibrium. Far different is it, however, with the man who is constantly worried, since neither time nor circum- 300 THE BRAIN AND NERVOUS SYSTEM. stance can do more for him than to press down the balance more heavily upon the side of both physio- logic and psychologic unrest. The Need of Mental Recreation. — With a terri- ble emotional incubus fastened upon a brain which is being forced to work in a single rut, as it is in the case of inventors, speculators, and promoters of schemes, it is easy to see why it soon comes to the end of its forces; and the hygienic hint therein con- tained is equally obvious. America is justly proud of her banker poet,^ who has found abundant time to enrich the world of letters while still engaged in a pursuit which often taxes the mental and emotional stability of its followers to its utmost. Why should we not also produce litterateurs from the stock- exchange, or art connoisseurs from among the ranks of other callings, the slavish pursuit of which is fraught with such disastrous results to the nervous system ? These are only a few ways that brain-rest may be obtained, but they are sufficient to indicate what brain-rest means. It is a very great mistake to suppose that cerebral activity can ever be brought to a stand-still. The brain is an organ which never ceases its activity, not even during sleep; of this we are often painfully made aware when we are suddenly awakened into the shivering consciousness of having experienced a bad dream. When we speak, there- fore, of measures other than sleep that may be adopted to obtain rest for the brain, we merely mean those which aim at diverting its activity into chan- nels that will afford a pleasant or soothing reaction upon consciousness. ^ Edmund Clarence Stedman. THE NEED OF MENTAL RECREATION. 3OI The truth of this fact is strongly borne in upon us by the numberless failures of brain- workers to obtain needed rest through efforts which entirely neglect to give it its due weight. It is certainly a great mistake to try to escape the Nemesis of an over-worked and harassed brain by a feverish tour of the continent, or by a few weeks' unwilling sojourn within the deadly dull confines of a country village. The familiar and much-quoted lines : *' Coelum non animam mutant, Qui trans mare currunt." (They change their skies but not themselves, That cross the seas.") are extremely pertinent to the case in point, and should be memorized by all who are striving to work out the mental and nervous salvation of the brain- worker. It is clearly impossible for the average stock- broker or scheme-promoter to become a shining light in the world of art or letters. That fact is fully appreciated in the proposition set forth. There is nothing lost, however, if such a person's efforts are not crowned with success, whereas the gain from the healthful mental gymnastics involved is often incal- culable. Thus far two general outlets for high-pressure cere- bration have been mentioned; there are many others, and one of the most valuable is the cultivation of fads. Fads may be said to constitute a perfect men- tal antitoxin for the poison generated by cerebral over-activity. It is not necessary that they should be at all expensive or involve a great amount of 302 THE BRAIN AND NERVOUS SYSTEM. time. The brain-worker whose purse will permit of no greater drain than that which is involved in the fad of stamp-collecting on a small scale, has just as great a chance for nervous salvation as the person whose bank account warrants the acquisition of a museum of art-treasures, and the writer feels confident that he has seen complete mental prostration averted in one instance by an overwrought young woman turning her attention to the study of the different weaves of oriental rugs. Among other fads which are helpful may be mentioned the collection of book- plates, rare books (which are often not expensive, though pleasantly elusive), old china and furniture, and old prints. The list might be prolonged in- definitely, but it will suffice to say that many not here enumerated will be suggested by a study of the circumstances surrounding the individual case. To all this will undoubtedly be objected the plea of lack of time. The answer to arguments formed on such a flimsy basis is, that all time which is spent in preparing one's self as a candidate for a sanita- rium, or, worse still, for a lunatic asylum, is like the proverbial edged tool in the hands of children and fools. Physical Over-work. — Next in importance to brain over-work, as regards nervous and mental well- being, comes the question of physical over-work. The two subjects are, indeed, closely interrelated, and what has been said of the former from the standpoint of pathology and hygiene applies very forcibly, to the latter. All motor activity, as has been shown, is the result of nervous energy; hence what we term bodily fatigue is in reality nervous fatigue. This PHYSICAL OVER-WORK. 303 does not imply, however, that the muscles do not undergo changes as the result of activity; they cer- tainly do, but such changes are only of secondary importance as com. pared with those which are at the same time produced in the nervous system. The changes pointed out by Hodge as occurring in the cells of the central nervous system of animals during extreme bodily fatigue have already been enumerated: There is still further evidence which goes to show that these central changes do not occur alone, but are accompanied by others that involve the intermediate portion of the neuro-muscular sys- tem, which we call the "terminal plate." According to Abelous,^ " spontaneous curarization"^ takes place in fatigued muscles through the action of toxic substances produced by muscular action. This he shows by the following experiment: A current of electricity was passed through the body of a frog from mouth to anus in such a way as to produce complete tetanization in a given time. The current was then shut off and the frog left undisturbed for a time. On reopening the circuit it was found that the muscles, tired after the first excitation, were no longer capable of a new tetanization. It was discovered, however, that if the nerve of the left hind leg were excited, ' Abelous, quoted by Brissaud, Le(ons sur les Maladies Nei-vetises, Paris, 1895, P- 323- 2 By curarization is meant an action similar to that produced by a drug called curare (or woorari). This latter is an extract of uncertain compo- sition, and is prepared and used by the natives of South America as an arrow-poison. The effect of immoderate doses of it upon the nervous sys- tem is to cause great muscular weakness and paralysis of all the voluntary muscles. The ends of the motor and sensory nerves are paralyzed ; the former being affected first. 304 THE BRAIN AND NERVOUS SYSTEM. contraction was insignificant or ;///, whereas excita- tion of the nerve of the right hind leg — whose artery had been tied — produced strong contractions in this limb. The conclusion drawn by Abelous from this ex- periment was that the toxic substances produced in the body by the tetanization of the muscles exerted their paralyzing influence through the circulation and upon the end-plates of the neuro-muscular system rather than directly upon either the nerves or the muscles proper. As nervous and muscular irritability was still preserved in the right hind leg, whose blood- supply was cut off by tying the artery, and not in the left, where the blood-flow remained unimpeded, Abelous's conclusion seems to be abundantly war- ranted. The results thus obtained from the study of fatigue experimentally produced lead us to consider whether or not they have physiologic analogues; whether, in a word, the state of the muscles of a man who is fatigued may be likened to that of the teta- nized muscles of a frog. In the stiffness of the limbs which follows a prolonged walk there would seem to be a beginning tetanization. And as to the sensation which accompanies this condition, it would certainly seem that we are warranted in looking upon it as a sort of incipient auto-intoxication. Both classes of experiments, that of Hodge as well as that of Abelous, are extremely suggestive, and point the way toward a clearer conception of the whole relation between nervous and muscular activity. They certainly lead us to be sceptical, to say the least, as to the absolute necessity of the building up of a vigorous muscular system — with all the output of PHYSICAL OVER-WORK. 305 energy which this process entails — as a safeguard to the maintenance of healthy mental and nervous bal- ance. On this point may be quoted once more that very keen observer, Dr. Holmes/ whose long and useful career is the best proof of the wisdom of his views. He says: " Do not think that a robust organization is any warrant of long life, nor that a frail and slight bodily constitution necessarily means scanty length of days. Many a strong-limbed young man and many a bloom- ing young woman have I seen falling and dropping away in or before middle life, and many a delicate and slightly constituted person outliving the athletes and beauties of their generation. Whether the exces- sive development of the muscular system is compati- ble with the best condition of general health is, I think, more than doubtful. The muscles are great sponges that suck up and make use of large quantities of blood, and the other organs must be liable to suffer for want of their share." Basing their judgment on the trite aphorism, '* Mens Sana in corpore sano," many enthusiasts would have us believe that if we are to entertain hopes of becom- ing intellectual giants we must set about acquiring the muscular force of a dray-horse; but if we take the trouble to consider how few of the shining lights of pugilism are also conspicuous in the arena of art or letters, for example, the fallacy of such a doctrine is at once apparent. It is not even true that the day laborer, possessed, as he generally is, of a fine musculature, is equally gifted in the matter of nervous system. The deadly * Holmes, loc. cit. 3o6 THE BRAIN AND NERVOUS SYSTEM. monotony of his avocation, with its freedom from emotional reaction, not infrequently proves too much for his mental and nervous stability. If any one desires proof of this, let him carry stones from one pile to another at a distance, say, of fifty feet, and when the first is exhausted begin to carry the combined stones of both piles back, one at a time, until both are heaped up on the site of the first. It will not require many rep- etitions of this process to convince the experimenter of its unquestioned ability to produce complete mental and nervous demoralization. Muscular exercise, like brain exercise, must, in order to be potent for the best good of the mind and nervous system, be such as to provoke pleasurable emotions. We have already spoken of the power of worry to evoke mental exhaustion, and we shall not have far to seek for illustrations of its equal capability to annihilate muscular energy. Contrast, for example, the utter weariness produced in the young physician — if he be conscientious — by his first few cases, with the fresh- ness with which his older, case-hardened confrere accomplishes his daily rounds; or the physical condi- tion of the mother who has nursed her child through a long illness, with that of the paid nurse who is sub- jected to the same amount of fatigue-producing work without the emotional strain. Regulated Exercise. — In thus emphasizing the meaning and danger of fatigue, there is no desire to discourage muscular exercise. The aim is rather, by force of contrast, to heighten its importance when carried out with due consideration to hygienic rules. The majority of people get all the exercise they need GOLF. 307 in the routine of daily life; it is for the sedentary and nervously constituted persons that we need to plan. For the former a daily walk of three or four miles in the open air, at the rate of about three miles an hour, is sufficient; for the latter the problem is much more difficult and entails a study of the individual case. Some nervous invalids are incapable of exert- ing their muscles at all without provoking an expendi- ture of nervous force which leaves them bankrupt for weeks, and for them nothing more than massage and carefully regulated passive motion is desirable. Others suffer from what may be termed a '' paralysis of voli- tion," and are really capable of enduring a great deal more than they think. They should, therefore, be handled with the greatest circumspection. Their exercise should be taken in the open air, since the monotonous round of Indian clubs, chest-weights, and dumb-bells is to them invariably irksome and fatig- uing. These persons need mental as well as physical gymnastics, and these, in the writer's opinion, are most abundantly offered by golf. Golf is one of the greatest boons, in the way of out- door exercise, yet offered to the nervously weak of both sexes. It is excellent from an esthetic stand- point, because the player's scene of action is a con- stantly shifting one and brings him face to face with Nature under new and varied aspects. Nor is this its only virtue. The mind finds both restful and absorbing occupation in the calculation of distances and in regulating the coordination of the muscles involved in the stroke. There need be no violent efforts, no hurry, no emulation; and the player may always stop at the very first signs of fatigue. Curiously 308 THE BRAIN AND NERVOUS SYSTEM. enough, however, the golfer is usually so completely preoccupied with the matter of ' ' hazards ' ' and '^ bunkers" that the amount of ground traversed is not appreciated, and delicate women often say that they are able to get over more ground, without fatigue, in pursuit of a wayward golf-ball than they had ever dreamed of in their most ambitious moments. Bicycling. — For the somewhat more vigorous and self-reliant neurasthenic the bicycle is an excellent means of educating the nervous system, but the scope of its adaptability is limited largely to male sufferers. It certainly is not good for timid and apprehensive females, and attempts on the part of such to conquer a natural aversion for it should be encouraged only in a very limited number of cases, since the nervous outputs these attempts involve are far more often attended with disastrous than with happy results. The use of the wheel implies work, often hard work; but it has a saving clause in the fact that it, even more than golf, affords opportunities for a constant change of scene. To the experienced rider the pecu- liar sensation, as of flying, which is often felt while wheeling along a pleasant road is very nerve-soothing, and gives him a sense of vigor that is indescribable. Often we have the opportunity to witness the delight of profoundly nervous but plucky patients on finding that they can ride the wheel several miles with com- fort, whereas they cannot cover the distance of a few blocks on foot without great mental as well as physical suffering. And in some cases this achieve- ment marks the turning-point in the road toward the lecovery of nervous health. Tennis is in most cases much too violent and HUNTING, 309 exhausting for persons of weak nerves, but both canoeing and boating are very excellent for those who have a fair power of self-command. In addition to the output of muscular energy they both bring into play the balancing and coordinating faculties, and thus avert the danger of irksomeness. Hunting.— To the neurasthenic of trained mind and innate, though perhaps undeveloped, love of Nature the sport of hunting often opens up new and varied fields of activity. It sometimes develops, for one thing, an unsuspected taste for taxidermy, and nearly alw^ays brings the special senses of sight, hear- ing, touch, and smell into a high degree of activity. The whole range of advantages is so enticingly set forth by a physician who found nervous and mental health in the sport, that we are impelled to quote parts of his story. He says : ^ "Travel was tried with some benefit, but I did not get the best results of my time till I took to the fields and forests — ' gun in hand.' I never hunted and never owned a gun until I w^as past fifty. ... I studied the habits of birds; used all the skill I could master in my efforts to get a shot, which often requires a great deal of strategy. . . . The eye is constantly under train- ing, the ear also; every footprint of Nature, every motion and sound must be caught and analyzed. If a nut falls, if leaves rustle, or any unusual noise is heard, an immediate investigation must be had, and a quick decision made as to the cause. . . . Thus led by the eye and ear, the muscles of the entire body are called into the most delightful activity, with the least possible effort of the will, nearly resembling the •-Dr. Holbrook's Hygiene of the Brain and Nerves, p. 198. 310 THE BRAIN AND NERVOUS SYSTEM. spontaneous movements of childhood. The muscles seem to obey the active senses with real delight and with much less sense of fatigue than in any other mode of exercise. . . . The muscular system gains in strength, blood is sent to the extremities and to the surface, the skin becomes active, the brain is released of its excess of circulation, the nervous system is rested, the entire man refreshed and renewed." There are still other modes of outdoor activity which are of undoubted value from a nervous and mental standpoint, but those already mentioned are sufficient to illustrate the underlying hygienic prin- ciples involved. To state the case briefly, the aim in all muscular exertion should be toward conservation rather than toward excessive outpoint of nervous energy in either its dynamic or its emotional form. It is thus, and only thus, that the organism can be brought into a condition which fits it to succumb to the regularly-recurring incidence of natural sleep. SLEEP. Of the reparative power of sleep and the necessity of securing it during the hours which Nature herself unerringly indicates, mention has already been made. It will be well, however, to consider the subject in greater detail, both in its physiologic and pathologic aspects. Physiologic Considerations. — As already stated, the waste-products of activity appear to be the prime cause of sleep, and on them probably depends the distribution of the blood which has been observed during this condition. To make the blood-supply to the brain the primary factor of importance in the SLEEP. 311 production of sleep — as certain physiologists have attempted — is, however, manifestly illogical, since drowsiness may be present synchronously with un- questionable cerebral congestion or the opposite ex- treme, cerebral anemia. Under ordinary circumstances normal sleep may be said to take place without profound lowering of blood-pressure, and it is more than probable that it is due to the benumbing influence of the waste-products of metabolism mentioned above upon the cells of those areas of the brain-cortex which preside over the senses. A strong proof of the truth of this hypothesis is found in the following observation of Striimpell,^ recorded many years ago : A young man had lost all power of sensation excepting through the right eye and the left ear. A bandage over the eye and a plug in the ear effectually barred all communi- cation between his brain and the outer world. At the end of two or three minutes of ineffectual attempt on his part to arouse the sense of hearing by clapping his hands, his efforts ceased; respiration and pulsation were deepened and retarded, and the re- moval of the bandage showed the patient with his eyes shut in genuine sleep. Additional proof of the correctness of the above hypothesis lies in the fact that the majority of persons who possess the ability to fall rapidly asleep are individuals whose waking life is almost entirely sustained by their external perceptions. For them the production of slumber simply entails the securing of shelter from the sounds and impressions of the air and the shutting out of other excitants by closing the eyes. After these pro- iStrumpell, Deutsch. Arch.f. klin. Med., 1864. 312 THE BRAIN AND NERVOUS SYSTEM. cedures very little remains for the production of ordinary consciousness, and sleep readily supervenes. From the experimental standpoint also we have important evidence bearing upon the points under consideration. By the aid of the plethysmograph, Mosso ^ was enabled to compare the circulation in the human brain, laid bare by erosion of the cranial bones, with the movement of the blood in other organs of the body. The occurrence of sleep caused a diminution in the number of respirations and a fall of six or eight beats in the pulse. The volume of the brain and its temperature were at the same time slightly reduced through a diversion of a portion of the blood-current to other regions of the body. If during sleep a ray of light was allowed to fall upon the eyelids, or if any organ of sense was moderately excited without waking the patient, his respiration was at once accelerated, the heart began tc beat more frequently, and the blood flowed more copiously into the brain. Similar incidents accompanied the act of dreaming. The renewal of complete consciousness was followed by an immediate increase in the activity of the cerebral circulation. Attempts have been made to trace a resemblance between certain of the phenomena of syncope and sleep, owing to the fact that unconsciousness is a common attribute of both conditions; but it is clearly evident from the facts already adduced that the pathologically bloodless state of the brain which accompanies the former condition is in nowise analo- gous to the much less marked lowering of blood- » Mosso, Ueber den Kreislauf des B lutes im menschlichen Gehirn, Leip- zig, i88i. INSOMNIA. 313 pressure which accompanies sleep. The attempted analogy between the stupor of alcoholic intoxication and sleep is also highly illogic, and will receive fur- ther attention in the consideration of the measures for inducing sleep. Insomnia. — From all the evidence at command we are justified in believing that if we can successfully disconnect, as it were, the cortical end-organs of the senses from stimuli coming to them either from within or without the organism, consciousness will be so far abolished as to produce sleep, and this gives us a rational basis upon which to work in the preven- tion of insomnia. Insomnia is of two orders — functional and sympto- matic, but only the former will be considered. This occurs most commonly in neurotic individuals and in overtaxed brain-workers, and may be complete or partial. As previously stated, many neurasthenics unintentionally exaggerate the extent to which they suffer from it. The pathologic basis of insomnia is probably to be sought, in the class of cases under discussion, in a persistence of the hyperemia, with its natural anatomic and chemic consequences, which accompanies intense cerebral activity. This sup- position is rendered all the more tenable by the recent discovery of Obersteiner^ of the presence on even the finer cerebral vessels of nerves which di- rectly govern the blood-supply to the brain. These nerves, the discoverer further tells us, are easily ren- dered paretic and lose their power to respond at a time ^ Obersteiner, Prof. H. " Die Innervation der Gehirngefasse," Jahr- buch f. Psychiatrie u. Neurologic, Band xvi, Hefte i u. 2, p. 215 et seq., 1897. 314 THE BRAIN AND NERVOUS SYSTEM. when those of other organs of the body respond readily. This being so, the acceptance of the patho- logic view expressed is not difficult, and it will be seen that the severity of the insomnia will vary with the extent to which the cortical centers of the brain are exposed to morbid activity through a sort of paretic hyperemia. Treatment of Insomnia. — For all but the most profound sufferers from insomnia the treatment is simple and easily carried out. Mental work should be performed during the first part of the day and restricted to four or six hours. The importance of outdoor exercise has already been emphasized. The bed-chamber should be cool ; the bed hard and its coverings light. A fairly long time should be spent in preparation for retiring, but care should be taken that the feet do not become cold durmg this time, since the sensory stimuli thus provoked may in them- selves be sufficient to keep the cortical centers alert and prevent sleep. Undue heat of any part of the body surface may also cause wakefulness ; but for certain people a warm bath taken just before retiring brings about the desired result. Those who persist in going over in their minds the affairs of the day after their heads have touched the pillow should at- tempt to divert brain-activity by giving the stom- ach something to work upon, such as a glass of warm milk, a cup of hot bouillon, or even a glass of beer. Any large amount of alcohol should not, however, be taken at this time, since between the stupor thus often produced and the healthful restora- tion of energy which accompanies genuine sleep there can be no rational comparison. The bad effects TREATMENT OF INSOMNIA. 315 of strong coffee taken at night need hardly be men- tioned. Prolonged insomnia, if it be absolute, is a very dangerous condition, and the measures necessary to overcome it are consequently more active. The patient — for the victim of continued insomnia must be regarded as a sick man or woman — should be kept in bed, and opium and its derivatives, as well as the whole group of so-called hypnotics, should be sedu- lously excluded. The mere application of mustard- leaves over the upper part of the chest and back for long-continued periods will frequently relieve uneasy feelings in the head and produce sleep for several hours. In using this remedy care should be taken not to blister the skin, since blistering is an unneces- sarily severe measure. Counter-irritation, which is, of course, the object of the treatment just advocated, may also be secured by the application of bottles of warm water applied to the feet and back, and by the use of warm compresses over the abdomen. Very gentle shampooing or "massage" applied to the head and neck four or five times a day for a few min- utes at a time is generally soothing. This should be done by the spread-out fingers, starting from the sides and back of the head, and being carried gently down to the clavicles and about the root of the neck. One of the best methods of depleting the blood- vessels of the brain is to draw the blood into the vessels of the abdomen by means of food. Food should, therefore, be given in small amounts at fre- quent intervals, and the largest meal should come at night. Gentle rubbing of the whole body, beginning with the lower extremities and working up, is a good 3l6 THE BRAIN AND NERVOUS SYSTEM. method of eliminating waste-products from the tissues, but should not be done after six in the even- ing and never longer than five or six minutes at any time. If carried out after the hour indicated or for a longer time than five or six minutes, the rubbing is likely to excite the patient and thus defeat the pur- pose for which it is undertaken. In any case the danger of producing excitement is lessened by the use of oil on the operator's hands. Such advice may be contrary to the laws which govern the technic of massage; it is, however, not massage but gentle rubbing that is indicated in prolonged insomnia. If these measures are faithfully carried out, the re- sort to sedatives and hypnotic drugs rarely becomes necessary, and the danger of the formation of vicious drug-habits is happily averted. Conclusion. — In closing, it is reiterated that affec- tions of the brain and nervous system are in greater measure preventable than those of other parts; conse- quently the mental and nervous salvation of the individual is, practically speaking, to a very marked extent within his own hands, and may be worked out by him through rigid attention to the guidance of hygienic laws. PHYSICAL EXERCISE. By G. N. STEWART, M. D. (Edin.), OF CLEVELAND, Professor of Experimental Medicine in Medical Department of Western Reserve University, Cleveland. PHYSIOLOGY OF MUSCULAR MOVEMENT. Spontaneous movement is the sign of life which appears the most typical and the most decisive to the popular mind. Nor is this instinct deceptive. For, although in the narrow, technical, and strictly scien- tific sense, life may exist without visible spontaneous movement, this is only possible for any considerable time in plants and in certain specialized animal cells: the blossom or the bacillus may live without moving, but not the bird; the liver-cell and perhaps the nerve-cell, but not the man. The Muscles. — All the movements that are so characteristic of animal life — not only the voluntary movements, but the involuntary movements of the heart, the stomach, the intestines, the iris, and other organs — are carried out by muscles, which make up nearly one-half of the weight of the body of a man, and a somewhat smaller proportion of the body of a child. The voluntary muscles — such as the biceps, which forms the rounded, fleshy mass on the front of the upper arm, and the gastrocnemius in the calf of the leg — are connected, usually by cords or bands of 317 3l8 MUSCULAR MOVEMENT. dense fibrous tissue, called tendons, to the bones, and hence are also called the skeletal muscles. They consist of long, cylindric fibers varying somewhat in length and breadth, but on the average about 3^ inch in diameter, and an inch or even two or three inches lono-. The fibers are marked with alternate dark and o light stripes, which run across their length, and from this appearance the skeletal muscles are termed striped or striated muscles. Each fiber is made up of a number of fine longitudinal fibrils arranged side by side, with a material of a different nature between them, the whole being inclosed in a thin sheath, called the sarcolemma. The fibers are united by connective tissue into small bundles, and these again into larger bundles, a number of which constitute what we call a muscle. In the connective tissue run the blood-vessels of the muscles. The capillaries, or smallest vessels, run close to the sarcolemma, but no vessel actually enters any fiber. The muscular fibers of the stomach, intestines, blood-vessels, etc., are much shorter and thinner than the striated fibers, and, having no transverse stripes, are spoken of as unstriped or smooth muscular fibers. The fibers of the heart occupy an intermediate position between the smooth and the striated muscular fibers. Like the latter they are transversely striped, but like the former they are not, in most individuals, under the control of the will. Muscular Contraction. — The characteristic phys- iologic property of muscular fibers is that when stim- ulated they respond by a shortening or contraction without any change of volume. In this way the ends of the stimulated muscles come closer to each MUSCULAR CONTRACTION. 319 other, and if they are attached to bones these are made to execute movements, the direction, extent, and force of which depend on the direction of the pull of the muscle, the nature of the joint in which the movement takes place, the size of the muscle, and the degree of intensity of its excitation. The contraction of muscle may be brought about artificially by stimulating the fibers directly, as by striking or pinching them, or by sending electric currents through them, or by suddenly heating or cooling them, or by putting into contact with them some chemic substance, such as common salt. All these forms of stimulation can be easily illustrated on the excised muscles of a frog. In the living body muscles are generally excited through the nervous system. In such a muscle as the biceps every mus- cular fiber is supplied with at least one branch of a nerve-fiber. The nerve-fibers are long branches, or processes, of nerve-cells situated in the gray matter of the spinal cord. These nerve-cells, again, are in close contact with other nerve-fibers running down from nerve-cells situated in the gray matter of the brain. When the biceps muscle is voluntarily con- tracted, *' something" which we call a nerve-impulse, some change in the condition of the nerve, sweeps down from a definite region of the gray matter of the brain along certain nerve-fibers to certain nerve-cells in the upper portion of the cord, and, modified, per- haps, in these nerve-cells, is thence transmitted by the motor nerve-fibers to the muscle. What this "something" is we do not know, but it is probably a chemic change, which we may imagine running along the nerve with a speed somewhat greater than 320 PHYSICAL EXERCISE. that of the fastest train in the world, and involving portion after portion of it, as an explosion runs along a train of gunpowder to one end of which a lighted match has been applied. When the nerve-impulse reaches the muscular fibers, it sets up in them changes of a different and much more energetic character, the external token of which is contraction. We must, therefore, regard the muscle-fiber, the nerve-fiber, and the nerve-cell as a single machine or as successive links in a chain. If one link gives way, the chain is broken; if something goes wrong with one part of the machine, the whole is thrown out of gear. For instance, if the nerve is divided or crushed at any point between the muscle and the spinal nerve-cells from which its fibers come, or the spinal nerve-cells are destroyed by disease, the muscle is not only paralyzed immediately, but in a short time wastes away and becomes little more than a mass of connective tissue. In like manner, although the process takes a longer time, removal or permanent disuse of a muscle or group of muscles, as after amputation of a limb, particularly in young persons, leads first to enfeeblement and then to actual decay or degeneration of the nerve-cells in the spinal cord which are connected with it. In course of time even the corresponding group of nerve-cells in the brain may show unmistakable signs of wasting or atrophy. It is, on the other hand, exceedingly probable — and this is one of the most important points in the physiology of rational physical training — that in- creased use of a group of muscles, especially during the period of growth, leads to an increase in the size and efficiency of the nerve-cells of the spinal cord AUTOMATIC MOVEMENTS. 32 1 and brain which are connected with them, as it is known to do in the case of the muscles themselves. Voluntary, Automatic, and Reflex Movements. — Most of our ordinary movements, and particularly those by means of which we act on our environment and adjust our relations to it, are brought about by a distinct act of the will. But certain nerve-cells con- nected even with striated muscles may discharge im- pulses that lead to automatic contraction of these muscles without voluntary effort and even in the absence of consciousness. Such are the nerve-cells which preside over the muscles used in ordinary res- piration, the chief of which are the diaphragm sepa- rating the chest from the abdomen and certain muscles that elevate the ribs. Although we may, and often do, voluntarily alter the rate or the depth of our breath- ing, yet in general we do not think at all about it, and in sleep, of course, it goes on entirely without our knowledge. The impulses that set the respira- tory muscles into action are discharged from a nerve- center or collection of nerve-cells in the medulla oblongata, a portion of the central nervous system which serves to join the spinal cord to the brain. Although the rate and intensity of its discharge are regulated by nerve-impulses carried to it by afferent, or sensory, nerves from the lungs and other organs, this respiratory center seems capable, even in the absence of such impulses, of sending out impulses along the efferent, or motor, nerves to the respiratory muscles. It is, therefore, spoken of as an automatic center, and the respiratory movements may be con- sidered in part automatic movements. But the most typical examples of automatically contracting organs 21 122 PHYSICAL EXERCISE. are the heart and the digestive canal, whose move- ments are entirely beyond the control of the will, ex- cept that in a few individuals an increase in the rate of the heart can be voluntarily produced and main- tained for a short time. A third group of movements embraces what are called reflex movements. Typical reflex move- ments are the winking of the eyelids when the eye- ball is touched, and the drawing up of the foot when the sole is tickled. Everyone knows that both are quite involuntary. The nerve-impulses which cause the contraction of the muscles concerned are dis- charged by certain groups of nerve-cells constituting the reflex centers for these movements, situated in the case of the eyelid-reflex in the brain and in the case of the foot or plantar reflex in the lower portion of the spinal cord. The discharge is brought about by the arrival in the reflex centers of afferent im- pulses set up in the sensory nerves of the eyeball or the sole by the contact or the tickling. It is not necessary for the discharge of a typical reflex move- ment that the person should be conscious of the stimulus which gives rise to the reflex, or should experience any sensation from it. Many reflex move- ments can be elicited during sleep. Work Done by Muscular Contraction. — A muscle is essentially a machine for doing work, but in the scientific sense the term work does not involve precisely the same idea as in the economic or the everyday sense; the former is wider than the latter. Thus, when a man lifts a weight against the force of gravity he does work in the scientific sense, whether the weight be a sack of coal, a book, the pros- TRANSFORMATION OF FOOD-SUBSTANCES. 323 trate form of an opponent on the football-field, or his own body as he ascends a ladder or a hill. The amount of the work done by a contracting muscle is measured in terms of the weight which it raises and the height to which the weight is raised. For in- stance, if a muscle raises a weight of a pound to the height of a foot, it is said to have done one foot- pound of work; if it raises two pounds to the height of a foot or one pound to the height of two feet, the work done is two foot-pounds, and so on. Transformation of Food-substances into Mus- cular Energy. — No work can be done without using up, or rather transforming, an equivalent amount of energy. Thus, a steam-engine transforms into work a portion of the energy stored up millions of years ago by the sun's rays in the primeval vegetation and set free in the burning of the coal. In like manner, a contracting muscle changes into work a portion of the energy stored up (again directly or indirectly by the sun's rays) in the food-substances, which are oxidized, that is to sa}^ burned at a comparatively low tem- perature, in its fibers. The " burning" of food-sub- stances in the muscle is essentially the same process as the burning of coal in the furnace of the engine, only in the muscle the oxidation takes place by some peculiar agency not at present thoroughly understood at a temperature of less than 100° Fahrenheit, while for the combustion of coal or of food-substances in a furnace a temperature of several hundreds of degrees is required. The products formed are, however, prac- tically the same whether the food is slowly burned in the muscles and other tissues of the body or rapidly burned in the fire, the only essential difference being 324 PHYSICAL EXERCISE, that in the body the combustion of the nitrogenous substances, such as white of ^^% or lean meat, is not quite so complete as it would be in a furnace, the nitrogen being given ofif in the form of urea, which can itself be further oxidized to nitrogen gas, carbonic acid, and water. Fat, starch, and sugar are fully burned in the body, the end-products being water and carbonic acid. As regards the proportion of the total energy of the food which can be converted into work, the muscles are more economical than any machine yet constructed by man, since they can, under favorable conditions, do work equivalent to one-fourth or even one-third of the energy of the food-substances con- sumed in them, a proportion far in excess of the efficiency of the best steam-engines. The most important of the food-substances used up in a contracting muscle is a sugar called glucose, or grape-sugar, which is formed in the body in digestion from starch and from ordinary cane- sugar, but also occurs in plants and can be produced artificially by heating cane-sugar with dilute acids. Another substance of importance is glycogen, some- times called animal starch. It is formed in the body from glucose and other substances, and is always present in normal muscles, although it diminishes in amount, and may even disappear altogether, when the muscles are strongly stimulated for a long time, as when spasms are produced in an animal by poison- ing it with strychnin. A certain amount of fat is also invariably present in muscles, and may be used up during their contraction. The nitrogenous substances of the muscle do not THE EFFECTS OF MUSCULAR EXERCISE. 325 appear, under ordinary circumstances, to furnish any large portion of the energy of the contraction, for mus- cular exercise, unless it is severe and prolonged, causes hardly any increase in the amount of such substances consumed, as indicated by the amount of urea excreted. On the other hand, exercise causes a marked increase in the quantity of carbonic acid eliminated by the lungs ; and we have already recognized carbonic acid as the form in which the carbon of fats, sugars, and starchy substances leaves the body. When, however, the food consists mainly of lean meat, which contains little but nitrogenous food-substances, these are util- ized by the muscles in contraction instead of the car- bonaceous sugar and fat, which, so to say, they select when a choice is offered them. Under all circum- stances a certain amount of nitrogenous or proteid food is required by the muscular tissue, for, as in all cells, the real, living framework of the muscle-fiber contains proteid substances as its essential constitu- ents. We may, in fact, conceive of the fat and the sugar as bearing the same relation to the proper sub- stance of the muscle as the water in the boiler and the coal in the furnace to the steam-engine — necessary for its work, yet perfectly distinct from it. THE EFFECTS OF MUSCULAR EXERCISE. Fatigue of Muscle. — It is a familiar fact that when the muscles are caused to work hard for a certain time they become fatigued. The process of fatigue can be best studied when a muscle — for example, one of the muscles on the front of the forearm which by their contraction flex or bend the fingers toward the palm — is made repeatedly to lift a weight attached by a 326 PHYSICAL EXERCISE. leather collar to a joint of one of the fingers, the hand and arm being fastened so that none of the other mus- cles can assist. The number of contractions and the height to which the weight is raised by each are reg- istered on a revolving drum, and the whole arrange- ment is called an ergograph. If the muscle is made to contract strongly and continuously, as when a heavy weight is held up by the finger, it rapidly becomes fatigued and soon the weight drops. But if each contraction is a short one, and is succeeded by an interval of rest, and if the weight is not too great, the muscle may go on raising the weight for a consid- erable time. Thus in an experiment of Lombard's one of the muscles of the hand lifted a light weight once every second for two hours and a half, or 9000 times in all, without showing any fatigue. An increase in the weight or an increase in the rate of contraction was quickly followed by fatigue of the muscle. Ultimately when the person has repeatedly raised a considerable weight with all the force which the muscle can exert, the time comes when a rapid decrease in the height of the contraction can be noticed, and sooner or later the effort to raise the weight fails. If the person still strives to raise the weight, a partial recovery of power takes place, after which the muscle again speedily becomes fatigued, and soon refuses once more to raise the weight. There is every reason to believe that when a muscle is fatigued by voluntary contraction the fatigue involves not only, nor at first chiefly, the muscular fibers themselves, but also the nerve-cells in the brain or cord. In fact, when the fa- tigue is pushed so far that it is no longer possible by a voluntary effort to cause the finger to lift the weight, RESTORATIVE PROPERTIES OF FOOD. 327 it is the nerve-cells, and not the muscular fibers, which first give out. For at this moment direct stimulation of the muscle by an electric current will generally cause it to contract and raise the weight. So far as the fatigue-process involves the muscle, it seems to be due to two things : the using up of the material necessary for contraction and the accumula- tion in the muscle of waste substances produced by the active muscle, for example an acid called sarcolactic acid, which resembles the acid formed in milk when it turns sour. The restorative properties of food-substances in fatigue of muscle show conclusively that these mate- rials are consumed in muscular contraction. The tak- ing of a small amount of sugar, for instance, has been found markedly to lessen the fatigue and increase the endurance of soldiers tired out by long marches, and we have already seen that of all the food-substances in muscle, sugar appears to be the most important for the contraction. The fact that it is rapidly absorbed from the digestive tube also accounts in part for its restora- tive effect. Some enthusiasts have spoken of the almost magic change produced by the eating of a handful of granulated sugar. But it must not be sup- posed that the action is a specific one. Sugar may act most quickly in restoring fatigued muscles, but other food-substances have a similar effect; for instance, fats (especially when taken in the form of soups along with certain of the constituents of meat-extract), and the proteid substances contained in eggs and in lean meat. Caffein, the active principle of coffee, also causes for a time a marked increase in the capacity of a fatigued muscle to do work as measured by the 328 PHYSICAL EXERCISE. ergograph. Small quantities of alcohol appear to have a similar efifect; but in larger doses alcohol depresses the muscular power. And it seems now to be well established that in severe and continuous ex- ertion, coupled with exposure to all weathers, as in war and in exploring-expeditions, tea, coflfee, and cocoa are much more suitable stimulants than alco- hol, although it ought not to be lost sight of that all of these things may be taken in excess. Trainers, also, as a rule, allow their men no spirits, and only very moderate quantities, if any, of wine or beer. That in addition to the using up of the substances necessary to contraction, the production of waste- substances more quickly than they can be removed is responsible for the onset of fatigue, is indicated by the fact that the blood of a dog completely tired out by running, when injected into the veins of a per- fectly rested dog, has been seen to produce in the latter all the symptoms of fatigue, which was not the case when the blood of a rested dog was injected. Further, the marked effect of massage of the muscles in remov- ing the effects of fatigue would seem to show that the passage of the excess of waste-products from the mus- cular fibers into the blood and lymph is favored by the kneading of the muscles, which increases the flow of these liquids through the muscular blood-vessels and lymphatics. Within certain limits the same effect on the flow of blood through the vessels of the muscles is physiologically produced during contraction, a very beautiful provision for giving the active muscle that increased supply of nutriment which it requires, and for carrying oflf at the same time the excess of waste- THE EFFECT OF EXERCISE ON THE HEART 329 substances which it produces. This is brought about in two ways: by the widening of the small arteries, and therefore of the capillaries, of the muscle, through the action of certain nerve-fibers^ which govern the caliber of the arteries, and at the beginning of the contraction by the pressure of the thickened muscle- fibers on the veins that carry the blood away from the muscles. These veins, like most others, are pro- vided with valves in their interior which only permit the blood in them to flow out of the muscles and toward the heart, but not back to the muscles. When the veins are pressed on the flow in the former direc- tion is increased. It has been actually observed that the quantity of blood flowing through one of the muscles used by the horse in feeding was three times as great when the animal was engaged in chewing oats as when the muscle was at rest. This is one of the local effects of exercise, and doubtless the increased supply of nutriment thus obtained is connected with the growth of muscles that are freely exercised, and which is so strikingly displayed in the "brawny arms" of the blacksmith and the general muscular development of the professional pugilist or acrobat. There are also certain general effects of exercise which are of equal physiologic interest and hygienic importance. The Effect of Exercise on the Heart. — It is well known that even a moderate amount of exercise causes the heart to beat more quickly. Thus in 74 healthy men it was found that running once or twice * These are called vaso-motor fibers. They act on the blood-vessels by increasing or diminishing the degree of contraction of the smooth muscu- lar fibers in their walls. 330 PHYSICAL EXERCISE. up and down two or three flights of stairs caused an average increase of 32 pulse-beats per minute, or not very far from 50 per cent, of the normal pulse-rate at rest, which is about 73 in the minute in the sitting posture and about 80 in the standing. The increase, however, was ver}^ different in different individuals, one man having a pulse-rate immediately after the exercise of 164 and another only 75. Unless the amount of exercise is excessive, although the heart beats fast, there is a steady, regular rhythm, so that the right ventricle sends more blood through the vessels of the lungs and the left ventricle more blood through the rest of the body than is the case when the person is at rest. The increase in the flow of blood through the lungs permits more oxygen to be taken into the blood and more carbonic acid to be excreted, and both of these circumstances are favor- able to the actively contracting muscles, which use up far more oxygen and produce far more carbonic acid than muscles in repose. We, therefore, see that the quickly yet strongly beating heart is the ready helpmeet of the hard-worked and hungry muscles with their rapidly accumulating waste products and their dilated blood-vessels. The Effect of Exercise on Respiration. — In order that the increased amount of oxygen may be easily obtained by the blood as it passes through the lungs, and the increased amount of carbonic acid contained in it easily discharged, more air must be taken into and breathed out of the lungs, and the respiratory movements are accordingly quickened during exercise as well as the heart. This acceleration of the breath- ing is brought about partly by the stimulation of the PHYSICAL TRAINING. 331 sensory, or afferent, nerves of the active muscles, which carry impulses up to the respiratory center, and partly by the direct effect of the carbonic acid, and perhaps other substances produced by the muscle, on the respiratory center as they are borne through it in the current of the circulating blood. The Effect of Exercise on the Skin. — Another general effect of exercise is the reddening of the skin owing to the dilatation of its blood-vessels, and the increased excretion of sweat from its glands. The eflfect of the increased blood-flow through the cutane- ous vessels is to heat the skin itself, but to cool the body, since more heat is given off from a warm sur- face than from a cold one. The evaporation of the water of the sweat has the same eflfect. In both of these ways, as well as by means of the increased ventilation of the lungs, the excess of heat produced by the active muscles is eliminated, and the tempera- ture of the blood, even during the most intense physical exertion, seldom rises much more than a degree. The effect of exercise on the digestive system, when it is regular and not immoderate in amount, is favorable. The appetite is increased; food is not only taken in larger quantity, but it is better relished, more fully and rapidly absorbed from the stomach and intestine, and more completely oxidized in the tissues. PHYSICAL TRAINING. Association with Mental Training. — The saying of Montaigne, which is sometimes quoted as a watch- word by the advocates of physical culture, that " we have not to train up a soul nor yet a body, but a man, 33^ PHYSICAL EXERCISE. and we cannot divide him," expresses a truth which lies at the basis of rational education. It is, indeed, the strongest plea for systematic training of the body that it helps in the harmonious development of the whole man. Reference has already been made to the effects of exercise of the muscles on the nerve-cells connected with them in the spinal cord and brain. We have seen how near together in the bundle of life lie the muscular fiber, the nerve-fiber and the motor nerve-cell. So-called muscular fatigue we have recognized as in part fatigue of the nerve-cell. It is equally true that so-called muscular training is at the same time a training of the nervous centers, and that what in ordinary speech we term muscular agility is but the outward expression of a nervous agility, a readiness of reception of incoming impressions and a promptness of discharge of efferent impulses on the part of certain individual nerve-cells and groups of nerve-cells, extensively connected with each other and drilled to act in concert. There is also good reason to believe that the effects of muscular training are not confined to the motor centers, but that they extend to other portions of the brain as well, even to those portions which are espe- cially related to mental processes. It has, for instance, been clearly shown that many of our ideas, and some of them apparently the most abstract, are dependent for their completeness and vividness on the memory of muscular movements. To take an example cited by Sir James Crichton-Browne, when we think of a circle we involuntarily repeat in memory, although not usually with our muscles, the movements of the hand necessary to draw a circle or the circular sweep KIND OF EXERCISE MOST ADVANTAGEOUS. 333 of the eyes necessary to view it. This, it is true, is not everything which is involved in our idea of a circle, but it appears to form an essential element in it. It is, indeed, not too much to say that the educa- tion of the nervous centers which have to do with the perception of ideas and with intellectual opera- tions would be extremely incomplete in the absence of education of the centers connected with muscular movements. The distinguished writer on mental diseases, whom we have just quoted, goes so far as to speculate upon the possibility that " swaddling-bands so applied at birth as to restrain all muscular move- ments, and kept on during infancy and childhood, would result in idiocy — a speculation to which the wretched muscular development of most idiots and imbeciles, and the fact that their mental training is most successfully begun and carried on through mus- cular lessons, give some countenance." Apart from its effect upon the mental powers and its value as a moral gymnastic, as teaching discipline, obedience, and courage, physical education, according to M. Georges Demeny, a noted French authority, has three main objects : ''to confirm health, to give a harmonious development to the body, and to teach how best to utilize the muscular force in the different applications which are demanded in life." The kind of exercise whicli is most advantage- ous has not been definitely settled by the experts, and still less by the nations. The Americans and the English prefer outdoor games and athletic sports. The Germans, and especially the Swedes, are above all patrons of systematic gymnastic exercises directed to the development in due order and proportion, of all 334 PHYSICAL EXERCISE, the muscles of the body. The truth appears to lie between the two extremes; and when we are free to choose the amount and nature of the exercise, as ouofht to be the case with those who direct the physical training of children and young people dur- ing the period of growth, both open-air sports and regular gymnastic exercises should have a place in our curriculum. For while outdoor sports and games are carried on, in general, under far healthier condi- tions and, as a rule, afford a greater amount of ex- hilaration and, therefore, of recreation than set exer- cises conducted in a gymnasium or in a stuffy bed- room, and being enthusiastically indulged in are not so liable to be shirked on slight pretexts, the develop- ment of muscles and education of movements pro- duced by them is apt to be haphazard and lopsided. They should, therefore, be supplemented by some system of regular gymnastics. During the period of development in childiiood and youth systematic training of the body produces the greatest results. Dr. Hartwell, the Superintend- ent of Physical Education in the Boston Public Schools, who has had great experience in this mat- ter, comes to the following conclusions : During the first period of growth, from birth till the close of the eighth year — a period characterized especially by the great increase in size and architect- ural completeness of the brain — both games and gym- nastics are valuable. But both should be simple, and should be directed rather to the development of such fundamental movements as those employed in walk- ing and running, in bending the body, and in main- taining the erect posture, than to the acquisition of DEVELOPMENT IN CHILDHOOD AND YOUTH. 335 such skilled movements as the movements of the hands and fingers in playing the piano or the violin, or in handling many kinds of tools, or such rapid and highly coordinated movements as are necessary in many games. The second period, from the beginning of the ninth to the end of the sixteenth year, is the time of most rapid growth in height and weight. In the increase in weight the muscles take the chief share, and the power of coordinating movements advances far beyond what was possible in the first period. This is the most important period for physical training, since neglect of it at this time can only be imperfectly remedied later on. Both athletic sports and gym- nastics occupy an important place as agents of phys- ical culture in this stage, and the "forms of exercise should be more varied, complicated, and difficult than in the previous period." The third period lasts from the beginning of the seventeenth to the close of the twenty-fourth year. It is essentially a period of mental and moral devel- opment, and physical culture should be directed to increasing and perfecting the control of the nervous system over the muscular movements, and in partic- ular over the vastly important group of skilled move- ments. During these years the handicraftsman, as a rule, acquires the delicate control of the muscles which he especially uses in his work, that manual cunning through which he is to earn his bread and which can hardly be fully attained to later on in life. To some extent the necessary labors of the workshop may, if carried on under proper hygienic conditions, replace special physical culture during the latter part of this 336 PHYSICAL EXERCISE. period. When systematic exercises are employed, those which educate the muscles, or rather the neuro- muscular apparatus, should preponderate, while in the whole of the first period and first half of the second hygienic forms of exercise should be the main thing. Sports and Gymnastics. — Having determined that a combination of athletic sports with regular gymnas- tics is the proper method of physical training, the question arises — What are the best forms of athletic sports and the best system of gymnastics ? No per- fectly definite answer can be given. But if we keep in mind the triple purpose of physical training, to improve and confirm the health, to develop the body and the mind, and to confer upon the individual the particular form of muscular or manual dexterity which he may need in the serious business of his life, it is not difficult to make combinations of the two forms of exercise which will approximately accomplish the end in view. Taken by themselves, those athletic sports which bring equally into play the upper and lower limbs (as wrestling, swimming, and rowing with two sculls or short oars and a sliding seat) are the best. But it is seldom necessary, and hardly ever desirable, to con- fine one's self to a single sport, and a game which involves chiefly movements of the legs may be supple- mented by a game or a gymnastic exercise in which the arms are mainly used. It is in the possibility of graduating and varying the movements, so as to exer- cise every muscle in its turn, that scientific gymnastics shows its superiority over mere athletic pastimes ; and of all the systems of gymnastics that first established by lying, expanded and promulgated by Zander, and THE AMOUNT OF EXERCISE. 337 known now by the name of " Swedish movements" appears to be the best and most complete. It is im- possible to do more than mention the snbject here, and the reader who desires fnll information in regard to it is advised to consult a special work upon the subject. The amount of exercise which should be taken cannot be stated in definite rules. Many persons, of course, remain in good health who take no system- atic exercise at all. Sometimes the daily w^ork pro- vides as much as is required, and if the conditions under which manual labor is carried on are healthy, it would be striving for an unattainable ideal to demand, in addition, a weary round of gymnastic exercises. Doubtless the gentleman farmer whose bodily exertion is confined to riding about his fields or following the hunt, might be benefited by gym- nastic training. But hardly the greatest enthusiast for physical education would expect a hard-working farmer or navvy at the end of his day's toil to find his chiefest relaxation on the horizontal bar or even in the mildest manipulation of Indian clubs. Ac- cording to Parkes, the amount of exercise which an ordinary man should take is equivalent to about 150 foot-tons, that is, the amount of work necessary to raise 150 tons to the height of one foot. This is very much the same as walking about 9 miles on a good, level road, or cycling about 18 miles at a moderate pace, say 9 miles an hour. At this rate a cyclist can cover with a given expenditure of energy, measured by the amount of carbonic acid produced and elimi- nated by the lungs, two miles to the foot- traveler's one. But as the cyclist forces the pace the expendi- ture of energy increases very rapidly owing to the 22 338 PHYSICAL EXERCISE. increase in the resistance opposed to his progress by the air. It should be remembered that a certain, and usually a not inconsiderable, amount of bodily exertion enters into the daily work of all healthy persons, and to this extent the amount of systemic exercise may be reduced. Excessive Exercise. — Exercise, as such, ceases to be physically beneficial when pushed to the point of exhaustion. The severe strain of prolonged exertion may indeed give rise to dilatation of the heart, and even to lesions of its valves and to aneurysm. A certain degree of temporary dilatation of the heart has even been observed in soldiers after a long march in heavy marching order. A very rapid, unequal, and irregular heart-beat shows that the exercise is excessive and must be more gradually undertaken. Certain diseases of the respiratory organs may also be caused by excessive exercise. Morally, however, the severest exercise may be of great benefit. For example, the grim determination which keeps the football-player in the field in spite of bruises and ex- haustion may be very unphysiologic and even injuri- ous as regards the muscles, but not necessarily so as regards the moral fiber of the man. For it is some- times well in more important moments in the march of life that when the weary muscles cry "Halt!" the steadfast will should cry "Onward!" and com- pel the muscles to obey. But as a hygienic train- ing, exercise should always be stopped before it becomes exhausting. This is especially true in the first and second periods of growth, and it ought to be carefully remembered that muscular relaxation is the natural complement of muscular contraction, and rest the complement of exercise. MUSCULAR EXERCISE IN DISEASE. 339 Environment and Clothing. — Another point of practical importance is that when exercise is taken in a gymnasium there should be most thorough ventilation, since the elimination of carbonic acid by the lungs and the demand for oxygen by the muscles are so much increased. For the same reason no tight clothing which would hamper the free movement of the chest should be worn. For many kinds of indoor exercise it is well to strip the upper part of the body, and there is no danger of taking cold so long as the exercise is going on. Immediately it is over, or in the intervals of rest, the body should be covered. In winter the room should be properly warmed, but not too hot. Muscular Exercise in Disease.- — It is impossible here to do more than mention a few of the diseases in which local treatment of the muscles, either by mas- sage (that is, stroking, striking, rubbing, or kneading) or by movements (passive, when carried out by the operator, active, when carried out by the patient), or by a combination of movements and massage, is em- ployed as a remedial measure. For further information the reader is referred to special works on this subject. Such treatment has been found of value in certain forms of dyspepsia, habitual constipation, gout, de- rangements of the function of the liver without any organic disease, obesity, neuralgia (including sciatica), nervous prostration, some forms of paralysis, espe- cially the acute paralysis of children, locomotor ataxia, St. Vitus' dance, writers' cramp, muscular rheumatism, some forms of dropsy, certain diseases of the heart and blood-vessels, lateral curvature of the spine, and sprains. 340 PHYSICAL EXERCISE. HOME GYMNASTICS. By Albert McConaghy, M. D., of Seattle, Wash. The series of home exercises herein set forth is intended to develop agility and suppleness and to encourage the normal activities of the muscular sys- tem. The aim is beneficent physiologic effect of exercise, rather than abnormal muscle-building ; flex- ibility rather than hardness. The different move- ments are so arranged that those afifecting the same parts of the body do not immediately follow one another. The avoidance of strain has been kept in mind ; and at first all the movements should be prac- tised lightly, always stopping short of actual fatigue. The effect of properly regulated exercise is to impart a sense of buoyancy and well-being, rather than one of exhaustion or depression. During the interval between the exercises especial attention should be paid to the acquisition of the proper carriage of the head, shoulders, chest, and abdomen. In this way all the ordinary movements, such as walking, sitting, stoopinr, reaching, etc., become developmental exercises of far more practical value than any daily system of home gymnastics. It must also be remembered that no indoor exercise can ever supplant the common, healthful outdoor sports, such as walking, running, bicycling, swimming, golf, cricket, etc. The importance of the abdominal muscles in all physical training should be emphasized. Lydston says: "Given the firm, well-developed abdominal muscle, it is hardly necessary to examine the rest of the muscular system. Any set of exercises which 'HOME GYMNASTICS. 34! gives good abdominal development imparts an excel- lent general development. Abdominal protnberance in individnals ont of condition is more apparent than real, and is dne to flabbiness of the abdominal walls rather than to increase of fat or girth." By walking a stated distance each day with the abdominal muscles in firm contraction, a rapid and substantial develop- ment of their power and tonicity may be obtained. In fact, marked reduction of fat and diminution of abdominal girth, and, more particularly, abdominal protuberance, may be accomplished, simply by con- centrating the attention on the abdominal muscles and keeping them in contraction while walking. When possible, it is desirable to have a trained medi- cal adviser to select the kind of exercises that are best adapted to the individual requirements, and to warn against the dangers that exercise may bring to persons with organic disease. Pregnant women should always avoid movements that cause strain of the abdomen and pelvis, and during menstruation the same pre- cautions should obtain. The following general rules should be carefully read before the individual exercises are begun : 1. Before beginning these exercises it is well to evacuate the bladder, clear the nose of all mucus, and drink a glass of water, not too cold. 2. Except when stated otherwise, the fundamental position in all these exercises is : heels together ; toes turned out ; chest upward and forward ; arms hang- ing loosely ; abdomen drawn in ; and chin down and in. 3. The time best adapted for exercising is in the morning before breakfast. It is at this time that the 342 PHYSICAL EXERCISE. vitality is at its highest, and the movements can be done with greater regularity. 4. The room should be well ventilated but free from drafts, having the windows down from the top and up from the bottom. It is best to exercise in a room other than the sleeping apartment. 5. The clothing of the body should be loose-fitting, so as to leave the movements of the body unimpeded. The night-dress answers this purpose very well. The feet should be bare or stockinged, as this allows the ligaments and the muscles supporting the ankle-joints to be brought into play, and thus strengthened. 6. The exercises should be performed before a mirror. This lends interest to the work and the faults can be corrected better. 7. The mind should be concentrated on the work, and each exercise should be performed with precision. If home gymnastics are practised with absolute regu- larity, they soon grow into the daily habits of life, and the disinclination to exercise which follows erratic performance soon disappears. 8. In all exercises where the arms are in extension they should always be stretched out as far as possible. 9. As all these exercises will have a tendency to accelerate the breathing and the heart's action, it is better to rest a half minute after each movement. 10. The weisfht of dumb-bells for male adults should be from one to three pounds each ; those for ladies and children, not more than one-half pound each. 11. All the exercises in this series, with the excep- tion of Nos. 2, 3, and 4, should be practised without dumb-bells. HOME G YMNASTICS. 343 Fig. 70. 1. Stretching Exercise (Fig. 70). — Lock the hands; stretch the arms out in front on a level with the shoulders. Without bending the knees, touch the floor, or as near it as possible. Straighten up the body, carrying the arms upward and backward above the head ; then bring the arms down laterally (inclining them back- ward) to the level of the shoulder ; then out in front to starting position. Through- out this exercise extend the arms as far out as they will go. The movements should be repeated ten times. 2. Dumb-bell Exercise, A (Fig. 71). — Bells on the shoulders. As the right bell is carried out from the shoulder, turn the head in the same direction. In bringing the right bell back to the shoulder, extend the left arm and bell, following with the head, and repeat. Do not allow the elbows to sink below the level of the shoulders, and do not roll the head — simply turn it, keeping the chin down. This is a good exercise to develop the arms, shoulders, and neck, and to cor- rect an habitually bad carriage of the head. Repeat ten times, and gradually increase to fifty times. 3. Dumb-bell Exercise, B ^^' (Fig. 72). — With the elbows fixed at the side, alter- nately touch the thigh and chest with the palms up. This exercise develops the upper and lower arms. Repeat ten times, and gradually increase to fifty times. 344 PHYSICAL EXERCISE. 4. Dumb-bell Exercise, C (Figs. 73, 74). — From the position with the arms at the sides carry the arms back and up to above the head ; then down to the shoulders, bending the wrists ; then out to the sides on a level with the shoulders ; then back and down to the side of body. This exercise is useful to correct round-shoulders and contracted chest. Repeat ten times, and gradually increase to thirty times. When the hands are elevated above the head, leg-exercise may be incorporated in this movement by rising on Fig. 72. Fig. 73. Fig. 74. the toes. As the arms are lowered to the sides, the body should be raised on the heels, bringing into action the extensor muscles. 5. Breathing Exercise (Fig. 75). — With the hands on the posterior aspect of the thighs slowly exhale all air from the lungs. As the arms are elevated to a position above the head, turn the palms up and the arms back at the same time, taking in a full, slow breath. As the arms are lowered, turn them backward and slowly exhale. The inspiratory act should be completed just as the hands come together above the HOME GYMNASTICS. 345 head, and the expiratory act should be completed as the hands reach the sides of the body. At the end of the expiratory act, bring the chest into a state of extreme contraction by crossing the arms in front and bending forward, at the same time making a forced expiration to get rid of the residual air. Keep the mouth closed, and exhale and inhale through the nose. In raising and lowering the arms be sure to turn them backward, as this throws the chest in a proper state of expansion. Quick, jerky breathing might impair the elasticity of the lung-structure in men past middle life. This movement, besides increasing the girth and contour of the chest, develops the muscles of respiration and increases the vital capacity, elasticity, and circula- tion of the lungs. Leg-exercise may be incorporated in the manner described in the preceding exercise. Repeat ten times. Breathing exercises are very valuable, and should be continually practised. Oc- casionally taking a deep breath while walk- ing or in front of a raised window is a very useful practice. Many indoor workers would be greatly benefitted if they would raise the windows of their offices occasionally and practise deep breath- FlG. 75. 6. Twisting Exercise (Fig. 76). — Rest the hands on the hips with the thumbs turned back. Fix the eyes on a point on the walls opposite each shoulder, so as to avoid vertigo in turning. Then turn the body from side to side facing these points, at the same time rubbing the hands firmly across the abdomen. 34^ PHYSICAL EXERCISE. Fig. 76. In rubbing the abdomen do not localize the pressure to any one spot, but cover the whole abdomen. The head is never moved, but kept firmly in line with the body. This exercise stimulates the peri- staltic action of the intestine, and is useful in cases of constipation and hepatic torpor ; it is also indicated when there is an excess of fat on the abdomen. By bringing into play the rotary muscles and ligaments of the spine, this exercise is an excellent one for a weak back. Repeat ten times, and gradually increase to fifty times. 7. Shrug Movement (Fig. ^f). — Ele- vate the shoulders as high as they will go without drawing in the head ; lower the shoulders ; rotate the shoulders forward and cross the arms at the wrists. Then throw the arms up, and when they reach the level of the chin, separate them and carry them backward, making a circle on either side of the body. This movement is an excellent one for round-shoulders and con- tracted chest. Repeat fifteen times. Leg-exercise may also be incorporated in this exercise, as well as in all the breathing exercises. 8. The breathing exercise (Fig. 75) should be repeated again for ten times. 9. Forward and Backward Bend (Fig. 78). — With the hands on the hips and the thumbs back, bend the body forward to a position at right angles with the legs ; and as the muscles of the abdomen relax, firmly knead them, going over the abdomen from the lower ribs to the pubes and lat- FiG. 77. HOME GYMNASTICS. 347 Fig. 78. erally. As the body is bent backward, brace it by resting the hands on the hips. In bending backward allow the chin to rest on the chest. On the forward bend turn the face npward, and thus avoid cerebral congestion. By bringing into play the erector spinse muscle, this movement is indicated for a weak back. It is also indicated in constipation, hepatic torpor, and excess of fat on the abdominal walls. Repeat ten times, and gradually increase to thirty times. 10. Side Bend (Fig. 79). — Bend the body to the side and touch knee, at the same time bringing the other hand into the opposite armpit ; then reverse and repeat. In bending to the side, keep the body in the vertical plane. The ten- dency to bend forward or backward should be avoided. This movement strengthens the abdominal walls, and is, therefore, a preventive against hernia. It also streno^thens the back. Re- peat twenty times, and gradually increase to fifty. 11. The breathing exercise (Fig. 75) should be repeated ten times. 12. Wind-mill Movement (Fig. 80). — The body should be bent at right angles to the legs, and kept in this position throughout the exercise. Bend the right knee, and touch the floor, or as near it as possible, with the right hand, at the same time carr}'ing the left arm upward and forward above the head. Then, as the knee is straightened and the right hand is carried above the head, the left knee and hand assume Fig. 79. 343 PHYSICAL EXERCISE. Fig. 8o. the position that the right one previously occupied. In changing from one side to the other do not elevate the body. This is a fine all-round exercise, and is especially valuable in cases of constipation, hepatic torpor, weak back, contracted chest, and round or drooping shoulders. Repeat ten times, and gradually increase to thirty. 13. Floor-exercise, A (Fig. 81), — Lie at full length on the floor with the hands under the hips. Raise the legs without bending the knees to a position at right angles to the body, and return and repeat five times, and gradually increase to fifty. This exercise strengthens the abdominal muscles, and is, therefore, a preventive against hernia, and is useful in cases of constipation with fatty abdomen. 14. Floor-exercise, B (Figs. 82, 83).^Lie at full length on the floor with the hands under the hips. Bend the knees, and bring them up on the abdomen and return to starting position, and repeat. Do this move- ment ten times ; then bring the knees alternately up on the abdomen fifteen or twenty times. The abdomen in persons unaccustomed to exercise is ordinarily very weak, and in such cases it is better to start with this exercise until the abdominal muscles have been strengthened. Then the other floor-exercise may be practised with greater ease. This exercise is useful in constipation and fat and flabby abdomen. Fig. 81. HOME GYMNASTICS. 349 15. The breathing exercise (Fig. 75) should be practised ten times. 16. Relaxing Exercise for the Knee (Fig. 84). — Steady the body by holding on to a chair. Bring the Fig. 82. Fig. 83. leg to the position illustrated in Fig. 84. Relax the leg, and then alternately extend and flex it quickly. This is a good exercise to increase the flexibility of the knee-joint. Repeat ten times, and gradually increase to thirty times. Fig. 84. Fig. 85. Fig. 86. 17. Relaxing Exercise for the Hip (Fig. 85). — • Steady the body by holding on to a chair, and swing the straightened leg backward and forward. 18. Relaxing Exercises for the Shoulder (Fig. 86). — Swing the arms alternately downward and upward, making two circles in front of the body. 3 so PHYSICAL EXERCISE, Fig. 87. — " The Winged Victory. THE BODY-POSTURE. By JOEL E. GOLDTHWAIT, M. D., OF BOSTON. Imperfect Use of the Human Body is the Cause of Many Cases of Chronic Invalidism. — Until re- cently this important truth has been neglected, even by the medical profession. When the body is used rightly, or in the normal state of health, there is the least possible strain or friction, no matter what the amount of physical labor; and, consequently, there exists the greatest amount of physical efficiency. Any departure from the normal use means a waste of energy, and must result in lessened efficiency of the individual, and whether this efficiency is judged by- physical or mental work is of little consequence. The proper poise of the body when erect is best appreciated by studying the statues or figures com- monly accepted as representing the most perfect types. The figures of the early Greeks (Figs. 87 to 89), modelled at the time when Sparta ruled Greece, are probably some of the best. Of the magnificent "Winged Victory" (Fig. 87) Bliss Carman says : ^ "So when art would embody in beauty the idea of * " The Making of Personality," Boston, 1908, p. 102. 351 352 THE BODY-POSTURE. triumph without weariness, of glad elation untouched by envious defeat, of high intelligence overcoming the barbarous and base, — when it would add to the Fig. 88. Fig. 89. fairest human loveliness some hint of superhuman power and dominion over a region more vast than earth,— it created the Victory of Wings, to be a last- THE PROPER POISE. 353 ing signal before our wondering eyes, and an incen- tive to that dignity of bearing which we behold only in the rarest personalities." In modern times there are numerous illustrations of the proper poise, such as that of the athlete pic- tured in Fig. 90 and the recent statues of Washington (Fig. 91) and Sherman (Fig. 92). The trunk represents the frame or cage in which the most of the important viscera or organs of the body are placed. The heart and lungs lie in the upper part enclosed by the ribs ; the stomach, liver, kid- neys, intestines, and many of the other smaller organs lie in the abdomen. When the body is erect there is plenty of room for all these organs, but none of them can work to their best ad- vantage if for any reason the space in which they lie is con- stricted. The erect standing posture is maintained by holding the body as tall as possible without actually rising on to the toes. In this way the trunk is given there is the largest space available for the organs ; the muscles of the front, back, and sides are in perfect balance^ none are strained ; the head is erect and so poised that none of the muscles are overworked ; the Fig. 90. its greatest length; 354 THE BODY-POSTURE. shoulders are so placed that they rest easily upon the upper and posterior part of the thorax or chest without causing any tension of the muscles ; the legs are straight, none of the muscles being strained, and the weight is finally borne chiefly upon the balls of the feet. In this position the chest is high and the abdo- FiG. 91. men is flat. From this position motion is possible also with the least waste of effort. Whether the movement be forward, backward, or sideways, there is no gathering of the body preparatory to the action, the gathering process all being accomplished by the THE ERECT STANDING POSTURE. 355 natural poise. In this position no one part of the body is overworked or strained, and all parts are used to their greatest advantage, so that each is properly correlated to the others. If, however, there is any departure from this poise in any part of the body, not only does the part in Fig. 92. which the change first takes place suffer, but all the rest of the body is necessarily involved. For instance, if the feet are changed in their formation so that the inner side of the foot sags, as is common in flat foot, it not only means that the foot itself is strained, but that the standing position must result in a slight bending of the knee both forward and to the inside, a position that cannot long be maintained without strain 356 THE BODY-POSTURE. and ultimate pain. In addition, with the bending of the knees, the hips are thrown out at the back and the entire trunk is thrown out of poise. When the shoulders are drooped forward, it is not possible to maintain the proper posture for more than a short time without a result- ant change in the normal curves of the spine, so that the upper part of the body is inclined forward, and with this the chest is naturally flat- tened, so that breathing and the heart-action must necessarily be in- terfered with, as must be evident in Fig. 93. With this the curve of the spine in the lower back is changed and the weight is thrown upon the legs in such a way that the knees are necessarily sprung and the arch of the foot strained. Before any motion from such a posture is made the individual must "gather him- Efyfc L,^ \ self," or, in other words, the mus- W\ "' cles must tighten and correct the i % undesirable attitude first, before a M» start is possible, and this means Fig. 93. that there is just that amount of energy wasted. In the normal erect carriage no group of mus- cles is overstrained, but all are used in a natural, healthy manner. If, however, the body is drooped forward, as is the case in the stoop-shoulder or round-shoulder (Fig. 93), the work of the muscles of the anterior part of the body is necessarily lessened. STOOP-SHOULDER. 357 These muscles are weakened because of the lack of work, while the back-muscles must work harder since they are obliged to hold the body from bending forward still farther. While, theoretically, these muscles would strengthen at first, the continued strain which results from the maintenance of this poise must be followed by an ultimate weakening of the muscles, the same as is true of the oarsman who, when over- trained, goes stale. If such an attitude is continued for long the overstrain of the back-muscles becomes so pronounced that great weakness exists, with vary- ing degrees of disability. It is to be expected that under snch conditions the strain will be felt partly in the back, but since in such a position the use of the feet and legs is not normal, these members will also be strained, with ultimate resulting disability. An attitude such as has been described is of far greater significance, and is undesirable for far higher reasons than simply the effect upon the framework of the body, since in such a position all of the viscera or organs of the abdomen and thorax are interfered with and their function is necessarily weakened. When it is realized that the difference in the diameter through the chest from front to back is, on an average, one inch greater when we stand erect than it is when we stand with the shoulders drooping forward, the re- striction which this must mean to the expansion of the lungs is evident. When it is realized that in the erect position the heart occupies the space between the breast-bone and the spine, with practically no space to spare, it is at once appreciated that when the chest is flattened or the breast-bone lowered, the space in which the heart acts must be narrowed, and conse- 358 THE BODY-POSTURE. quently the heart action interfered with. In this forward position not only are the lungs and heart em- barrassed, but the muscles of the abdomen, not being properly used, become weaker and sag forward, caus- ing downward displacement of the stomach and the intestines as well as the liver and kidneys, causing disturbance in circulation and interfering with the normal action of each. Many of the cases of constipation and indigestion, to say nothing of the irregular pains in the abdomen so commonly met with, are to be explained in this way. The circulation of the spinal cord is dependent very largely upon the tone of the muscles of the spine, and it is at once obvious that if the muscles of the spine are weak the circulation in the spinal cord must also be weak. When it is realized that in the spinal cord are many of the nerve-centers which have to do with the control of the muscles of the legs and arms, and which are also associated with control of the organs of the trunk, it is evident that if the vigor or the tone which should exist in these nerve-centers is not up to the normal standard the organs supplied by these nerves must necessarily suffer. Many of the conditions of nervous weakness, such as the so-called nervous indigestion, may be explained in this way. Postures such as sitting, rising, walking, stoop- ing, or lying are, of course, of quite as much im- portance as the erect posture ; but the chief point to be remembered, to whatever use the body may be subjected, is that the trunk or cage in which the organs lie shall not be constricted. If the spine is bent in the middle, as is the case when the body slumps or stoops, as is shown in Fig. 94, both the ^HE SITTING POSTURE. 359 chest and the abdominal cavity must be narrowed, with resulting restriction to the action of the organs. In sitting or rising, or stooping or walking, whatever the work, it should be the aim to keep the trunk straight, or in practically the same position as that Fig. 94. held when the body is standing fully erect. No harm can come to any of the viscera if, when standing, the body is held erect ; while, on the other hand, if the ordinary slouching or slumping postures are taken, 360 THE BODY-POSTURE. the functions of all the viscera lying in these two cavities must be interfered with. The importance of the foregoing should be borne in mind in planning or in undertaking occupations, and many of the occupations which are considered harmfi^l can be made much less so if the individual understands the way in which the body should be used, and avoids the unnecessary strains which fre- quently result from ignorance or indifference. Every- thing that causes or leads to harmful postures should be avoided. Drooping of the shoulder forward is the most common departure from the normal posture. The cases seen in childhood usually appear at the period when the clothing of the infant is changed for the clothing of the child, and is largely due to the fact that the ordinary underwaist, the garment to which the clothing is chiefly attached, is usually so designed that it brings all the pressure upon the outer or mov- able parts of the shoulder (Fig. 95). Since the main- tenance of the shoulder in the erect position depends upon muscle-effort, if continued strain is put upon the muscle it must tire, the same as the muscles tire in the attempt to hold the hand at arm's length from the body for any length of time. If it is impossible to hold the arm extended for more than a few minutes, it is equally impossible to hold the shoulders erect if much weight is put upon them. When it is appreciated that as the average child is dressed, with the stocking-straps attached to the waist, the weight represented by the pull of the clothing is from three to five pounds, the fact that the muscles tire is not extraordinary. The weight is not too great THE UNDER WAIST. 36 1 if it is applied in the proper place, and the harmful feature can easily be overcome by having the waist made so that the load is carried upon the upper part of the shoulder near the base of the neck with the Fig. 95. straps across the chest so arranged that no interfer- ence with the breathing can occur (Fig. 96). If during the growing period the child can be dressed properly and can be kept in otherwise good general health, there is no reason why the common stoop- 362 THE BODY-POSTURE. shoulder, or "angel-wing" child, should be so com- mon. The round-shoulder occurring in the adult is, as a rule, the result of occupation, general weakness, or indolent habits of posture, which allow the support- ing back-muscles to become overtired, so that the body inclines forward, the posture then representing simply a posture of fatigue, and can be overcome by Fig. 96. mechanical supports to relieve the strained muscles. The part of the body most commonly showing symp- toms of overstrain is the lower back, and this is due to the fact that the hip-bones are joined to the sacrum, the bone upon which the spine rests, by two oblique articulations, called the sacro-iliac joints. These joints have plane surfaces, and the strength of the BACKACHE. 363 joints or the stability of the joints depends upon the tone of the muscles and ligaments. If for any reason the muscles become overtired, the strain is naturally thrown upon the ligaments ; these in turn soon tire, and the joints themselves become strained. It is the strain of the sacro-iliac joints that explains many of the cases of backache, particularly common with women and especially prominent at the time of the menstruation, but also seen in men, and frequently designated as lumbago or rheumatism. In such con- ditions not infrequently the pain which results from such strain is referred to the legs. This results from the fact that the nerve-trunks which supply the legs with power and sensation pass directly over these joints, with the result that if the joints are much irritated or strained, the nerves are similarly irritated, and the sensation is felt in the part of the body supplied by that nerve. Many of the cases designated as sciatica or rheumatism are to be explained in this way. The leg-pains of children are most likely to occur at night, the children frequently awakening with the complaint of aching in the legs. This condition is most often described in childhood as "growing pains." All of these conditions can naturally be relieved by the relief of the strain of the joints, and the proper treatment, after the relief has been ob- tained, consists in strengthening the muscles and im- proving the poise, so that the joint-strain cannot recur. In studying or in relieving the strains which result from imperfect poise, all the contributing factors should be recognized. A common faulty habit seen in children, and to a considerable extent in adult men, is standing with the hands in the trouser- 3^4 THE BODY-POSTURE. pockets, especially if the trouser-pockets are low, in the style which has been conventionally proper during the past few years. That such posture must necessarily result in drag-o:ino: the shoulders forward is well shown in the accompany- ing illustration (Fig. 97). It is at once apparent that not only are the shoulders dragged forward, but also the chest is flattened, the back hollow in the lower part, and the stomach protruding more than is normal. Naturally, in correcting the resultant round- shoulder, the causative habit should be broken. Bad habits in sitting should be corrected. The body should be held erect or inclined backward, but always remembering not to bend in the middle. The exces- sive deposits of fat in different parts of the body should be over- come in so far as is possible. The large abdomen seen so commonly in men or women at middle life, or beyond, means that the center of gravity is Fig. 97. changed, and the only way in which easy poise can be main- tained is to throw the body backward at the top. This necessarily results in strain to the ligaments of the back and neck. To relieve such strain, naturally NERVOUS PROSTRATION. 365 the poise should be changed, but the excessive weight must be reduced before the resultant strain can be prevented. The effect which the normal use of the trunk muscles has upon the circulation in the spinal cord is of the utmost importance. Many of the cases of so-called nervous prostration are to be traced not simply to the work or worry to which the individual may be subjected, but to the waste of energy which must result from the imperfect way in which the body is used, and the interference with the circulation in the spinal cord and consequent weakness of the nerve-power which necessarily results. In other words, it is not the load which breaks the bearer down, but the way in which the load is carried. Our bodies were given us for use, and they were intended for hard use, and they are capable of withstanding the strain of hard use, provided they are used so that the differ- ent parts are spared unnecessary strain and undue waste of energy. Many persons are capable in poten- tial of the development of much energy, but as a matter of fact, because of the way in which they use their bodies, they generate but little. To speak me- chanically, a forty horsepower engine frequently de- velops only twenty horsepower, and the twenty horse- power is developed in such a way that the machine may be damaged more than if the full forty horse- power were developed. It should always be remembered that the human being is made with a physical body, a mind, and a spirit, and the three parts are so dependent, each upon the other, that any influence on one must affect the whole. If the body is strained and the physical 366 THE BODY-POSTURE. energy is wasted, there will remain less energy for the use of the mind and the spirit. If the mind is over- strained, the body is less able to do its work, and the spirit is weakened ; while if the spirit is weakened, the mind and body both fall far below their normal standard of efficiencyo DOMESTIC HYGIENE. By D. H. BERGEY, M. D., Dr. PH., First Assistant, Laboratory of Hygiene, and Assistant Professor of Hygiene and Bacteriology, University oi Pennsylvania. The subject of domestic hygiene includes all those factors in the home life of the individual which may be concerned in affecting his general health. Many of these factors, such as the ventilation, heating, water-supply, and sewage-disposal of the house, oper- ate with equal force upon all the occupants, while other factors, such as the nature and quality of the food and the methods of preparation, operate more particularly upon individual occupants. Domestic hygiene, therefore, has reference to all those conditions and arrangements of the household which may exert a detrimental influence upon the health of the occu- pants. It also embraces a consideration of the arrange- ments and conditions which tend toward the improve- ment of the general health of the occupants, because the general health may be conserved not only by removing or avoiding those factors and conditions which directly or indirectly injure health, but also by introducing those factors and conditions which tend to improve the general health, and thus fortify the system against the contraction of disease. 367 368 DOMESTIC HYGIENE. CONSTRUCTION AND FURNISHING OF DWELLINGS. Location. — The first consideration in the selection of a site for a habitation is the nature of the soil with regard to dampness and organic impurity, since these are the principal factors in rendering a soil unhealth- ful. The house should stand upon a site the subsoil of which is naturally dry or is properly drained and free from organic impurity. The configuration of the surface, the elevation, and the exposure are the most important factors in rendering the location favorable for a healthy habitation. The nature, source, and amount of the available water-supply should be in- vestigated. The possibility for the economic and safe disposal of all refuse matter must also be considered. The location should be of sufficient elevation to secure good drainage away from the house. A southern exposure is preferable, especially in colder climates. The proximity of large bodies of water and of marshy areas also influences the healthfulness of the location. The habitation should be so situated with relation to others surrounding it that an abun- da7tt supply of fresh air a?id sunlight can be secured. The healthful influences of sunlight and fresh air cannot be ignored. The absence of sunlight and the deficiency of fresh air are the most important predis- posing factors of disease in the homes of the poorer classes in our large cities. When the house is located on open ground, a southern or a western exposure is preferable in order to secure the greatest amount of sunlight in that portion of the house most constantly- occupied. The windows require protection with blinds and awnings in summer, to exclude the heat and CONSTRUCTION AND FURNISHING OF DWELLINGS. 369 glaring eflfect of the sun ; but in winter the full and free action of sunlight, because of its purifying influ- ence upon the air of the house, should be secured, at least during a part of each day. Foundation and Walls. — x'iside from the internal arrangement, the character of the walls, the materials of which they are composed, and the number of layers of these materials employed are important Fig. 98. — Double foundation walls; h.iv, air-space between inner and outer walls of house; h,j, air-space in foundation-walls; a, arched roof of basement ; r.a, r.a, reversed arch of basement floor. factors in determining the health fulness of the house. So far as materials are concerned, there is no great hygienic difference in the selection of wood, stone, or brick, but the walls and foundation of the house ■should be so constructed as, so far as possible, to exclude dampness. This can be accomplished by means of double walls — that is, by providing an air- space between the inner and outer surfaces (Fig. 98). In this manner the walls are rendered damp-proof and yet are not made impervious. The foundations and 24 370 DOMESTIC HYGIENE. walls should be as dry as possible, and in damp soils this can be secured only by draining the subsoil below the foundations, and by cementing the foundation- walls and cellar-floor. The roof of the house must be carefully constructed and frequently examined in order to prevent leaking. The material of which the roof is constructed is of no hygienic significance so long as it excludes rain. The rain-water falling upon the roof should be con- ducted away from the house through proper rain- leaders, so as to prevent the soil of the locality from becoming unduly damp from this cause. The internal arrangement of the house is of equal importance with the site, materials, and mode of construction. The height and number of stories, the size and arrangement of the rooms, and the disposi- tion of doors and windows, all have an important influence upon the health of the occupants of a house. The minimum height of the stories may be stated as nine feet, while the maximum height may be placed at fourteen feet. The amou?it of cubic space which should be supplied for each person is about looo cubic feet. A room 9 X 12 X 9 feet would contain the amount of cubic space required for an adult. With the height of a room less than nine 3r more than fourteen feet, the problem of ventilation is rendered more difficult. In a room less than nine feet in height the other dimensions of space must be increased beyond those just given in order readily to supply the requisite amount of fresh air per individual, and, in consequence, the ventilation and heating become less efficient, because it is more difficult to secure regular movements of volumes of air on a horizontal plane CONSTRUCTION AND FURNISHING OF DWELLINGS. 37 1 than in a perpendicular direction. On the other hand, in rooms over fourteen feet in height, there is a ten- dency for the air to stagnate in the upper portion of the room and thus hinder the regular and complete displacement of the contained air by fresh air. So far as possible, the rooms should be so arranged as to minimize the energy expended in going from one part of the house to another ; consequently stair- ways should be avoided as much as possible. Unless the price of land demands it, the house should not be more than two stories in height. This v^ill necessi- tate the extension of the building on a larger area of ground than is otherwise the case. So far as the architectural conditions are concerned, the effect can usually be made as pleasing, if not more so, in a two- story house as in one that is three or four stories in height. There is no doubt that the ventilation and heating of a house two stories in height are somewhat more difficult than in one having the same number of rooms, but which is three or four stories in height, owing to the difficulty of distributing currents of air in a horizontal direction. This difficulty does not, however, outweigh the evident advantages afforded in other directions. The cellar should be well lighted and properly ventilated, and no refuse matter should be allowed to accumulate in it. If the cellar is allowed to become the dumping-place for refuse materials, the contained air will become tainted and find its way into the living rooms and vitiate the air of the entire house. The floor of the cellar should be impervious, preferably of cement laid on a concrete foundation. The cellar walls should be laid in cement so as to be as nearly impervious as possible. When constructed in this 372 DOMESTIC HYGIENE. manner the cellar may be kept clean and dry, and thus prevented from becoming a source of detriment to the health of the occupants. The kitchen should also be well lighted and venti- lated, because the most important work of the house- hold must be performed in this room. Scrupulous cleanliness should be exacted in the kitchen. The sinks should be carefully cleaned each day, so as to avoid the accumulation in them of grease and refuse matter, from which foul odors may be generated. The refrigerator should receive especial attention with regard to cleanHness. Unless the refrigerator is kept scrupulously clean, odors will develop that will taint the food contained in it and perhaps prove a cause of ill-health in the household. IVIechanical and chemical cooling apparatus may be used in connection with refrigerators. These maintain uniform cold and dryness without the use of ice ; and may be utilized to manufacture the necessary table ice. They are clean and germ free. However, their expense is still too great for ordinary domestic installation. All the stairways should have an easy slope. The steps should be broad and low, so as to minimize the energy expended in going from one story to another. The hallways should be well lighted, so as to avoid dark corners in which dust may be allowed to remain unnoticed and undisturbed. All unnecessary draperies and curtains should be avoided, because they permit dust to settle in them. The curtains should be com- posed only of such materials as permit of frequent laundering. Plush or velvet-covered furniture is also objectionable, because it does not admit of satisfactory eleaning: Where su-eh- furniture is in use, it woivld CONSTRUCTION AND FURNISHING OF DWELLINGS. 373 be preferable to provide linen covers which could be frequently removed and laundered. The disposition of doors and windows should be such as to facilitate, so far as possible, the admis- sion of fresh air and sunlight, the two principal health-giving agencies in nature. An effort should be made to have doors and windows on opposite sides of rooms, in order to facilitate cross-ventila- tion. The windows should be wide and extend to the ceiling, so as to give access to plenty of light and air. During the summer months the glaring effect of the sun may be obviated by awnings. All win- dows should be carefully screened with mosquito net- ting so as to exclude flies and mosquitos. These insects are not merely objectional as sources of annoy- ance, but also because they can serve as the carriers of disease. It is especially on the latter account that these insects should be rigidly excluded from houses. Walls and Wall-coverings. — The hygienic in- fluence of wall-coverings is frequently neglected. It is usually the custom to cover the walls with wall- paper, and when this becomes soiled, another layer is placed over it. This process is often continued until the weight of the paper on the wall is so great as to become detached en masse. The practice of repaper- ing without previous removal of the old, soiled paper cannot be condemned too strenuously. In this manner the filth accumulated through months and years of constant occupation is merely covered over, and may give rise to serious illness in the occupants, and is especially likely to retain the germs of disease in the house if efficient disinfection is not practised. When repapering is necessary, the vSoiled paper should always be removed and the walls scrubbed 374 DOMESTIC HYGIENE, with some efficient antiseptic solution, such as chlorid of lime, before a new coat of paper is applied. The use of wall-papers cannot be recommended from a hygienic standpoint. It would be far preferable to have the walls painted or kalsomined. Painted walls may be scrubbed and cleaned without suffering any detriment. Kalsomined walls can, when soiled, receive a fresh coating of kalsomine. The use of enameled brick for interior walls, with metal ceilings, gives a most pleasing effect and meets all hygienic requirements. There is no doubt that, at least in part, the robust health of our ancestors is to be attributed to the fact that wall-papers were not then in general use. Usually the interior walls received frequent and liberal coatings of whitewash, and in this way were rendered aseptic at quite frequent intervals. It is well known that freshly slaked lime is one of the most efficient disinfectants. Floors and Floor-coverings. — It is not generally recognized that the floors and floor-coverings in most houses are mere receptacles for filth carried on our shoes from the streets. The dirt is rubbed off on carpets and other floor-coverings, and settles there, to be distributed into the air of rooms through dusting and sweeping, thus becoming a direct menace to the health of the occupants. The floors beneath the carpets are often so constructed as to afford additional receptacles for the surplus dust which penetrates the floor-coverings. Under these conditions the slightest agitation of the floor-coverings by sweeping will serve to raise clouds of dust laden with the germs of dis- ease, and there is no doubt that this is a fruitful mode of disseminating disease. The floors should be impervious and free from cracks and crevices. Wooden floors can be placed VENTILA TION. 375 in such a condition only by means of oil and paint. Here again the economy practised in the rural dis- tricts — that oi painting the flooj^s instead of covering them with carpets — tends to lessen the danger of dis- seminating disease. It is true that, to some extent, the same conditions are found in some of the better class of modern dwellings. Very pleasing effects can be obtained by means of inlaid floors of different colored woods. With painted floors, the use of carpets and Japanese matting as a floor-covering is not required. Instead of carpets and matting, a few rugs may be used, and these meet all the hygienic requirements. They are not permanently fastened to the floors, as is the case with carpets, consequently they can be removed bodily at frequent intervals and the floor thoroughly cleaned. Carpets, on the other hand, are usually allowed to remain in place for months and even years, resulting in an astonishing accumulation of dust underneath, even with the greatest degree of cleanli- ness permissible under such conditions. VENTILATION. The necessity for maintaining the purity of the air of our homes is generally recognized. During the winter months it is impossible to keep the contained air of the same degree of purity as the outside air, since there is a certain amount of accumulation of the impurities arising from respiration, perspiration, and combustion. It should be our endeavor, how- ever, to keep this accumulation as low as possible. This is accomplished by dilution — that is, by bring- ing in a constant supply of fresh outside air to dis- place an equal portion of the contained air. 376 DOMESTIC HYGIENE. The principal clianges in the air of dwellings arising from respiration, perspiration, and combustion are rise in temperature, increase in water-vapor, in- crease in carbon dioxid, decrease in oxygen, and gen- eration of various forms of dust. In order to keep the alterations in the air of dwellings as low as possible we resort to ventilation, by diluting the air of the enclosed space by a constant introduction of fresh air. It is quite exceptional to find that the air of dwell- ings or places of general assemblage is so changed with regard to the oxygen and carbon dioxid content as to give rise to discomfort to the occupants. If dis- comfort is experienced it usually is due to increase in the temperature and humidity of the air, because high temperature and high relative humidity exert marked disturbing influences on the health and comfort of human beings. The relative proportion of carbon dioxid in the air is taken as an indication of its purity. This is done, not because the carbon dioxid is in itself injurious in the amounts usually encountered, but because it is readily estimated and has been found by de Chaumont to be a fair indicator of the relative purity of the air. The estimation of the amount of carbon dioxid in air depends upon the principle that it is equal to the amount of precipitation produced in a definite quantity of lime-water (or similar solution) by a known volume of air. A simple household method for roughly estimating the proportion of carbon dioxid in air consists in washing measured quantities of the air with yi ounce of lime-water in glass-stoppered bottles of different sizes (Fig. 99). If no precipitate is produced on shaking lo^-^ ounces or more of air with J^ ounce of lime-water in a glass-stoppered bottle, the VENTILA TION. Ill air may be regarded as being of proper degree of pur- ity. If, however, a precipitate is formed in a bottle of greater capacity than loj ounces, the air is vitiated by respiratory impurities or the products of combus- tion, or both. It must be remembered that outside air constantly contains carbon dioxid in amounts ranging from 0.03 to 0.05 per cent. So long as the contained air of our houses contains carbon dioxid as the result of respira- \ J / \ ^ s / LIME WATER ♦J0Ppf=08 UMEWATEK 6-toz. NorfT. 10 i J 1 1 / \ \i IME WATER |:h 2-1: oi. N0PPT--30 r b Fig. 99. — Household method of estimating carbon dioxid (Fox). tory impurity, not exceeding 0.05 to 0.07 per cent, — that is, 0.02 per cent, in excess of the outside air, — we may regard the ventilation as satisfactory. DeChaumont found that the relative purity of the air of a room can be determined in an approximate manner by the olfactory sense. The first impression obtained on entering such a room from the outside air is the best criterion of its purity. The odor of organic matter given off from the bodies of the occu- pants in a crowded room is very offensive, and the 378 DOMESTIC HYGIENE. relative amount present is readily detected. Pure air will appear fresh and sweet, while organic impurities will render the air close, very close, or fetid, accord- ing to the amount present. In overcrowded rooms there is always an excess of humidity in the air. The moisture in the air, when excessive, becomes a source of discomfort, because it diminishes the normal evaporation of moisture from the surface of the body, and consequently favors the retention of impurities in the body that should be regularly eliminated. In this manner excessive humidity of the air may also prove injurious to health. The amount of moisture in the air that is most healthful is about 50 per cent, of saturation, provided the temperature is at the same time about 68° to 70° F. The relative purity of the air of a room may be determined by estimating the relative humidity and noting the temperature. These conditions of the air may be learned from the records of a register- ing hygrometer, an instrument which indicates and records the changes in the relative humidity and the temperature of the air. The same informa- tion may be obtained with a psychiometer. This observation, while more accurate, requires more skill and the use of hygrometric tables. When the outside temperature is near the freezing- point, it is impossible to ventilate by merely opening the doors and windows. On this account ventilation is intimately connected with the problem of heating, since the cold outside air admitted displaces a corre- sponding amount of warm air. In the ventilation of buildings we aim to bring in fresh outside air in such a manner as to avoid drafts, since there is probably VENTILA TION. 379 nothing more detrimental to health than a draft of cold air striking any portion of the body. We seek, therefore, to bring in the fresh air in a number of small continuous streams so as to prevent the sudden cooling of the contained air, as well as to avoid the production of drafts. The sensation of draft may also be overcome by bringing in the fresh air at such a height that it cannot impinge directly on the bodies of the occupants and at a temperature approximating that of the air of the room itself. Ventilation may be brought about either by natural means, as the result of movements induced by heated columns of air in ventilating flues, or by artificial means, as with fans or blowers. The former is known as natural ventilation, and the latter as artifi- cial ventilation. The fre- quency with which the air of a room is changed will depend upon its size and the number of the occupants. A space of looo cubic feet occu- pied by one individual will require a complete change of the air three times in each hour, in or- der to maintain its purity at the required standard. Many devices have been suggested for bringing in fresh outside air in natural ventilation. The sim- plest of these is the insertion of a board under the Fig. ioo. — Window-ventilation. 380 DOMESTIC HYGIENE. lower sash of a window (Fig. 100). This simple arrangement allows the entrance of fresh air at the junction of the lower and the upper sash, and gives the incoming air an upward tendency. The cold air rises toward the ceiling and is distributed in all direc- tions and then gradually sinks to the floor. In artificial ventilation the fresh air is either pro- pelled through the house by means of a blower, or the contained air is abstracted by the same means, the fresh air in this instance gaining entrance through cracks in doors and windows and through porous walls and floors, or through special inlets. The results obtained by these methods — propulsion or abstraction — are equally satisfactory, although the propulsion method is preferable, because the incom- ing air may be warmed by passing it through or over steam coils, and the point of intake may also be selected with reference to the greatest purity of the air. The ventilation of bedrooms is a matter of very great importance. The custom of sleeping in rooms which permit of opening the windows at night is being introduced more and more extensively. If the bed is properly screened so as to avoid drafts this cus- tom is inducive of better health. Even in cold weather a plentiful supply of fresh air should be admitted to bedrooms. If the occupants accustom themselves to these conditions, and provide sufficient bed-coverings, great benefit will result from sleeping in rooms with open windows. During the day the windows may be closed so that the room may be warm at the time of retiring. HEATING. 381 HEATING. The object in heating our dwellings is to maintain the temperature at or near such a point as has been found most^ agreeable and most efficient in conserving the heat of the body. ' A temperature of 70° F. is agreeable to most persons. In the absence of arti- ficial heat, in winter, our bodies lose their own heat quite rapidly and suffer in consequence. Heat may be supplied in several different ways, as by means of stoves, open fire-places, hot-air furnaces, petroleum heaters, gas-radiators, and steam or hot- water radiators. When the heated object is placed in the room to be heated, we have what is known as direct heating, and when it is placed in some other part of the house we have indirect heating. Stoves give rise to a great deal of annoyance, be- cause of the dust produced and because of the un- equal distribution of the heat. The same objections apply to open fire-places, and these also give rise to unpleasant drafts. Similar objections may be raised with regard to heating with petroleum and gas. In addition these fuels utilize large quantities of oxygen and thus rapidly impoverish the air of the rooms heated in this manner. As has already been stated, ventilation is intimately connected with heating, since it is impossible to bring in fresh outside air without displacing a correspond- ing amount of the warm contained air. For this reason it is more economical and satisfactory to ven- tilate with previously warmed air, thus combin- ing ventilation and heating. This combined sys- tem of ventilating and heating is exemplified in ovdmsiTy furnace-heating, in which the only source 382 DOMESTIC HYGIENE, of heat is that supplied by the air which has passed through the furnace and become heated. There are several other systems of combined ventilation and heating in use, the most satisfactory of which is by steayn radiators placed in stacks^ through and over which the fresh outside air passes on its way to the different parts of the house. This combined system of ventilation and heating is now in very general use, not only for private dwellings, but also for office- buildings, hospitals, hotels, and schools. By regu- lating the size of the flues and the speed of the blower, a fairly definite amount of warm air may be supplied to each room according to its relative size and location. In ordinary dwellings it is usually un- necessary to employ a blower to propel the heated air, as the increased temperature imparted to it while passing over the steam-coils causes it to expand and thus gives it an upward tendency. The expansion of the air brought about in this manner is usually sufficient to produce the movement necessary for con- ducting it to all parts of the house. In such a combined system of ventilation and heat- ing it is necessary to remember that exits of corre- sponding size must be provided in each room for the escape of an equal volume of the contained air, since no more fresh heated air can be brought into a room than the amount of contained air that is leav- ing it at the same time. Oversight of this necessary provision is frequently the cause for dissatisfaction with this method of ventilation and heating. In the heating of dwellings two things are to be guarded against ; these are excessive temperature and undue dryness of the air. Aside from these two HEATING. 383 factors, the heating of dwellings has no particular hygienic significance, except in the production and distribution of dust and the gases resulting from combustion. Excessive temperature, undue dryness, as well as undue amounts of dust, are most fre- quently encountered in furnace-heated houses. Excessive temperature may be avoided by proper control and regulation of the fire. Undue dryness of the air is less readily controlled. During the winter months the relative humidity of the outside air is generally not very low, but by the time it has passed through the furnace and become heated, its relative humidity is excessively low, simply on ac- count of the expansion of the air induced through increase in temperature. The dryness of the air may be overcome, at least in part, by keeping the water-reservoirs of the fur- nace filled with water. This will give opportunity for the air to take up moisture on its way to the rooms to be heated. Besides this, several other measures have been introduced for increasing the humidity, such as placing a moistened sponge or a small jug filled with water before each inlet-opening. The production and distribution of dust are readily controlled by the person attending to the furnace-fire. By opening the dust-flues before shak- ing or dumping the fire, most of the dust passes up the chimney instead of finding its way into the upper portion of the house through the hot-air shafts. The hot-air shafts should be taken apart and cleaned each fall before the furnace-fire is started, in order to rem.ove the dust accumulated during the summer, otherwise this dust will find its way into the living- 3^4 DOMESTIC HYGIENE. rooms in the first weeks during which the furnace is in use, and hence may prove of decided detriment to the health of the occupants. It is probable that this dust is, at least in part, answerable for the colds contracted at this season of the year, because of its Fig. ioi. — The " Nevo," an apparatus for cooling the air. irritating effect upon the mucous membrane of the respiratory tract. Devices for Cooling the Air. — During the summer months it is desirable to cool the air. The method in common use is by the use of small electric fans. These serve to propel the air through a room at a high rate of speed, and thus bring about a cooling effect by the greater evaporation from the surface of WATER-SUPPLY. 385 the body because of the rapid renewal of the sur- rounding air. This method of cooling the air is ap- plicable on the small scale, as each fan acts only in the room in which it is placed. The air of an entire house may be cooled by pass- inor it throuo:h a chamber filled with ice. This, however, is a very expensive method. Passing the incoming air through a screen over which a spray of ice-water is falling will also serve to cool the air. Liquid air has been introduced recently as a means of cooling the air in summer, and has proved satis- factory in the ventilation of theaters. Within recent years Professor Gates, of Washington, devised an apparatus for cooling the air, which, it is claimed, can be operated more cheaply than a stove. Pro- fessor Willis Moore, of the United States Weather Bureau, has also devised an apparatus — the "Nevo" (Fig. loi) — for this purpose. Neither of these appli- ances has as yet been so perfected as to pass beyond the experimental stage. Some apparatus of this kind is greatly needed. LIGHTING. The subject of lighting has already been discussed in detail in the chapter on the Bye (pp. 236 and 254), and requires no additional consideration here. WATER-SUPPLY. Consideration of the purity of the water-supply is of equal importance with that of the purity of the air-supply. According to the teaching of sanitarians of the present day, the principal water-borne diseases are typhoid fever, cholera, diarrhea, and dysentery. 25 386 DOMESTIC HYGIENE. The specific causes of typhoid fever, cholera, and dysentery are now generally accepted to be well- known species of bacteria. The mode of entrance of these bacteria into the system is by way of the mouth, and takes place usually through the ingestion of infected water or infected food. The bacteria causing these diseases are thrown off from the body of the patient by way of the intestinal or urinary tract — that is, with the feces or urine. From these facts it will be seen that we usually contract typhoid fever, cholera, or dysentery by taking into our stomachs something which had previously passed through the intestinal tract of some other person. Hence it will be evident how important it is to have a water-supply that is free from these infective materials. Municipal Water-supplies. — In thickly populated districts where the citizens have joined together to form municipal governments, the individual has the right to expect, and even demand, of the municipal authorities certain safeguards against agencies likely to jeopardize his health. In such communities the regulation of the purity of the water-supply is trans- ferred from the individual to the municipal authori- ties. The individual has a right, therefore, to de- mand of the municipality a water-supply that is ample in quantity for all ordinary domestic uses and reasonably free from materials detrimental to health. In localities where natural water, ample in quantity and of reasonable purity, cannot be obtained, it is in- cumbent upon the municipal authorities to purify the water that is least polluted and most readily obtained. The question of municipal water-supply has received WA TER-SUPPL V. 387 a great deal of attention from sanitarians in recent years. Purification plants have been, or are now being, installed in a number of municipalities. The method of purification employed in any city varies with the inherent character of the water of the locality ; for instance, the water of the Ohio and Potomac Rivers has been found to be of such a char- acter as to be more satisfactorily purified by the method of rapid filtration through sand, with the addition of alum as a coagulant to restrain the fine particles of clay found in these waters. The water of most rivers of the Southern States is of a similar nature. The water of the rivers of the Middle and New England States generally contains smaller amounts of clay, and for the purification of these waters the slow sand-filters, without the use of alum, have been found most satisfactory. Domestic Filtration. — In those municipalities in which the water-supply is not free from danger to health, and where the local finances have thus far prevented the installation of satisfactory purification plants, the individual householder is obliged to apply such measures for rendering the water-supply safe as may be required by the local conditions. In many cities and towns where the water-supply has been notoriously bad for a number of years, individual householders have resorted to a variety of measures to remedy the evil. Many of the hospitals, hotels, apartment- houses, schools, and private dwellings are equipped with individual filters which operate on the principle of the rapid sand-filters, using alum as a coagulant. These filters purify all the water entering the build- 388 DOMESTIC HYGIENE. ing, and if properly constructed and intelligently managed, prove quite efficient. Many household- ers purify the water used for cooking and drink- ing by using filters composed of cylinders of unglazed porcelain, baked infusorial earth, or of sandstone. These filters act merely as strainers, since their fine pores prevent the passage of any bacteria. The ser- viceability of these filters is, however, of short dura- tion. Usually in a few days the bacteria in the water grow through the pores of the filter and appear in the filtered water. Unless the filters are boiled or baked at frequent intervals, the filtered water will in time contain more bacteria than the applied water. It is necessary, therefore, to scrub and boil filters of this class once or twice a week in order to maintain their efiiciency. Other measures adopted for the purification of drinking-water in the household which are of value are distillation and boiling. Special forms of appa- ratus for distilling drinking-water have been devised (Fig. 102). A pure water is one which does not contain anything that may be injurious. All surface-waters and many ground-waters contain colon bacilli derived from human or ani- mal excrement. The colon bacillus in itself may not be injurious, but it is possible for the excrement of per- sons suffering from typhoid fever, dysentery, or cholera to gain access. Water containing colon bacilli has for a long time Fig. 102. — Domestic water-still. PLUMBING AND DRAINAGE, 389 been regarded with suspicion. In the minds of some bacteriologists a water should be condemned if it con- tains more than two colon bacilli in 100 c.c. It should be the aim in the filtration of water to reduce the num- ber of all bacteria to less than 50 c. c. , and remove all the typhoid, dysentery, and colon bacilli. PLUMBING AND DRAINAGE. Sewers and Drains. — Where a general water- supply has been introduced, it is necessary to provide Fig. 103. — Anti-D trap. a way for the removal of the waste- water. In most modern towns a system of underground drains or sewers has been installed in order to carry the house- hold wastes away from the town limits. Where such a system of sewers has been provided, the household waste of each house is discharged through a four- to six-inch iron pipe into the sewer under an adjoining street The large iron pipe which carries the sewage away from the house is known as the house-drain or 390 DOMESTIC HYGIENE. soil-pipe, and into this drain is discharged all the waste from kitchen-sinks, laundry, bath-tubs, water- closets, and wash-basins. All the connections with the house-drain, such as bath-tubs, sinks, water-closets, etc., are constructed in such a manner as to retain a small amount of Fig. 104. — Method of connecting waste-pipe with house-drain. water in a bend of the pipe so as to seal the connection and thus prevent the escape of gases from the house- drain into the rooms. Such a water-seal in the pipes is called a "trap" (Fig. 103). In the plumbing of modern houses the house-drain is constructed of heavy wrought or cast-iron pipe of the same diameter throughout its whole length. It is provided with a trap between the house and the sewer, so as to prevent the escape of air from the sewer through the house-drain into the house. It is also supplied with a ventilator opening between the house and the trap for the entrance of fresh air. PLUMBING AND DRAINAGE. 39 1 The house-drain is extended for several feet above the roof of the house, aud its upper extremity is left open to favor a free circulation of air throughout its entire length. When constructed in this manner, and with all sink and water-closet connections prop- erly trapped, there is no danger of the escape into the house of any air contained in the house-drain or the street-sewer. All the connections of pipes entering the house- drain should do so at an acute angle (Fig. 104), and they must be tight, so as to prevent leakage of fluids or gases. This is a point that cannot be too rigidly observed. The principal danger from leaky joints is not so much the escape of gases, as the leakage of liquids and their accumulation on the premises. In fact, in modern dwellings, where the plumbing has been satisfactorily introduced, there is very little cause for apprehension from the so-called "sewer- gas," because in modern sewers and house-drains the air contained therein is not much more impure than the air of the overlying streets. In the absence of a general sewerage system the house-drain may discharge its contents into a cess- pool. Where cesspools are in use, they should be located at such a point and constructed in such a manner as to avoid the contamination of neighbor- ing wells or streams. As cesspools require cleaning from time to time, sanitary engineers have sought to find satisfactory ways to take care of sewage. The best method in use at present is the suhsiirjace irrigation method in which the sewage is discharged into a system of 392 DOMESTIC HYGIENE. Open tile drains lying six to ten inches below the surface. The sewage is discharged from a small Fig. 105.— Wash-out closet. tank which holds the accumulations of about half a day and discharges automatically twice a day, carry- FlG. 106. — Wash-down closet. ing the material into all the ramifications of the drains. The nitrifying bacteria of the soil purify the sewage that flows from each of the pipe connections. PLUMBING AND DRAINAGE. 393 Modern Bath-rooms and Toilet-rooms. — The general introduction of bath-rooms and toilet-rooms into houses has followed the provision of adequate water-supplies and the construction of sewerage-sys- tems. These factors have had a beneficial influence upon the health of the inhabitants of modern towns. The introduction of bath-rooms and toilet-rooms has made it possible to secure a much greater degree of personal cleanliness, and it has brought about a marked reduction in diseases disseminated through sewage-polluted water. Fig. 107. — Closet-flushing tank. The toilet-rooms should be supplied with closets of the wash-out or wash-down type (Figs. 105 and 106), and should be flushed by means of a separate water supply furnished by a small tank of from two to three gallons capacity. Such tanks are known as '^ water- waste preventers^ ^ (Fig. 107), because the amount of 394 DOMESTIC HYGIENE. water contained in them is sufficient efficiently to flush the closet each time it is used, and thus serves to prevent the use of excessive amounts of water for such purposes. The bath-room should have the floor and side walls covered with tiling, so as to be impervious. The bath-tub should be porcelain-lined cast iron, as these are durable and readily maintained in a satisfactory hygienic condition. The inviting appearance of the bath-room fixtures will increase the frequency of their use. DISPOSAL OF GARBAGE AND ASHES. The health of the household can be preserved by the prompt removal of all materials which may serve as a source of nuisance in the form of disagree- able odors or of irritating dust. Consequently provi- sion must be made for the systematic removal of garbage and ashes. Garbage may be disposed of in several ways : It may be burned in the kitchen range if the family is small. In larger households other ways of dis- posal must be provided. Special furnaces have been devised for the consumption of garbage. In most cities and towns the municipality provides regular scavengers, whose duty it is to collect the garbage at regular intervals. Where this system is in vogue, the collections should be made at least once daily during the summer months, and two or three times a week during the remainder of the year. Complaints should be made to the proper officials if the collectors are derelict. NUISANCES. 395 The disposal of ashes is a question which has received the attention of municipal authorities to a considerable extent and still awaits a satisfactory solution. The injurious effects of allowing ashes to accumulate on the premises are generally recognized, but their satisfactory removal has given rise to a great deal of discussion. For hygienic reasons the ashes should be removed at short intervals, — once or twice a week, — and in such a manner as to prevent the produc- tion of dust or the dissemination of litter. To over- come the latter factor, it would be preferable to provide separate collectors for waste-paper and refuse of like nature, so as to prevent their admixture with ashes. The dissemination of dust arising from the careless transference of ashes from boxes and barrels to the carts may be overcome by dampening the ashes a short time before the collector makes his rounds. NUISANCES. Under nuisances we may class such disturbances as foul odors, noxious fumes, loud noises, dust, smoke, and soot. Nuisances may not be directly detrimental to health, but they are indirectly injurious in that they engender discomfort and annoyance. Usually, these factors arise outside the home, and are, therefore, beyond individual control ; this is especially the case with noxious fumes arising from certain manufactur- ing industries, the loud noises of cities resulting from traffic over rough pavements, the shriek of factory and locomotive whistles, and the tolling of bells. Foul odors mav arise within the house throuo^h neglect of proper cleanliness of cellars, sinks, drains, 396 DOMESTIC HYGIENE. and toilet-rooms. The odors arising from these places are best controlled by strict cleanliness. The use of various deodorants for their removal merely substitutes one odor for another, thus masking the odor without really removing it. The noxious fumes arising from certain manufac- turing establishments are sometimes difficult to con- trol. Industries in which the generation of such fumes cannot be obviated should never be located in the residential portion of a town, but should be so located as to avoid becoming a nuisance, preferably in the outskirts of the town. The noises of our modern cities are of such a nature in general that many of them, as the blow- ing of steam-whistles and the tilling of bells, could be avoided. These could be reduced to a minimum always, and in many instances dispensed with en- tirely. The rumbling of trains, trolleys, and the heavy traffic on the streets, with attendant noises, frequently passed without notice by the well, are a source of great annoyance to the sick. Smooth pavements aid in reducing the noise from street traffic, and the more general introduction of self-propelling vehicles will also serve to diminish this source of annoyance. The transference of the surface street- railways to subways, although probably a long way off, will be an important measure in affording relief from this form of nuisance. The dust of city streets is not only a nuisance, but a direct evil. It serves to distribute the pathogenic bacteria which are deposited on streets and pavements by promiscuous expectoration, as well as in the dis- NUISANCES. 397 semination of the equally objectionable horse-manure. The advent of the trolley car has brought into opera- tion a different and equally dangerous form of dust in the nature oijine sand-particles., resulting from the pulverization of the coarse sand used on wet and slippery rails. Aside from the injury to the eyes, these sand-particles produce irritation of the throat and lungs, and hence lead to a lowered vitality of the mucous membrane lining the respiratory tract, thus paving the way for subsequent infection. There is strong ground for the opinion that the marked increase in recent years of diseases of the respiratory tract, especially of pneumonia, is attributable to the influ- ence of dust of this nature. The removal of these nuisances will go far toward rendering our homes more healthful. The enforce- ment of laws against promiscuous expectoration in public places, the more efficient cleansing of our city streets (not the perfunctory cleansing in vogue at the present time, which is attended with the distribution of clouds of dust along the course of the street-clean- ing gang, but the systematic flushing and cleansing of the streets in such a manner as to avoid raising dust and at such a time as not to interfere with traffic), and the introduction of underground railways, will serve to overcome in large part the discomfort and danger from the dust generated upon the streets. The smoke- and soot-nuisance is one that can be overcome to a great extent if the proper measures are introduced. For those who live near lines of steam railroads or large manufacturing establishments, the smoke and soot generated are sources of great annoy- ance. This is especially the case where bituminous 398 DOMESTIC HYGIENE. coal is used. Oil, when used as fuel, also gives rise to the production of smoke and soot. Devices for the consumption of the smoke by the fire under the boiler have been constructed. These serve to remove the greater portion of the smoke and soot, but are not in general use because they increase the first cost of the machinery and interfere somewhat with the efficiency of the engine. This problem still awaits a solution which shall be applicable under all conditions. The more general utilization of gas and electricity will serve to eradicate the evil in some instances. HOUSE=CLEANINQ. In order to understand what is meant by the term ^'house-cleaning," it will be necessary to define the word clemi in its hygienic sense. The ordinary con- ception of the word clean is quite different from the chemist's conception of the word. To be chemically clean, an object must be free from everything that might interfere with or vitiate a chemic analysis. The sanitarian's conception of the word clean is, however, quite different from the chemist's, as well as from the ordinary conception of the meaning of the word. From a hygienic standpoint cleanliness means the absence of the specific causes of disease. Looking at the subject from this standpoint, house- cleaning signifies the removal of all factors which are concerned in the propagation or dissemination of dis- ease. While it is evident that in actual practice we rarely attain the ideal, it is essential, nevertheless, that the ideal should always be before us so that we may HOUSE-CLEANING. 399 approach it as nearly as may be. In house-cleaning, therefore, it should be our aim to remove all disease- producing agents from the premises, as well as those factors which might tend toward the propagation or dissemination of disease. For these reasons sweep- ing should not be allowed. All dust should be re- moved with a moist cloth or sponge or an oiled mop. The most satisfactory method of cleaning carpets and rugs on the floor is by the use of vacuum clean- ers, especially the electric sweepers. These appli- ances are a great saving of labor and are far more efficient than any other method of sweeping. The dust is extracted from the. carpets and even from the floor beneath the carpets. The electric sweepers are also useful in cleaning walls, hangings, and furni- ture. Where the floors are covered with large rugs the outer edges of the floor can be mopped up with an oiled mop before sweeping, bringing the materials on the floor on to the surface of the rug, from which they are removed subsequently with the electric sweeper. In this way no dust is disseminated about the room. The great purifying agents employed in house- cleaning which have been handed down to us by our forefathers are washing-soda^ soap^ and hot water ^ and these have not been improved upon as to sim- plicity, efficiency, and cheapness by any of the scientific discoveries of late years. Hot soap-suds and hot solutions of washing-soda are efficient germi- cides as well as satisfactory cleansing agents, and when freely used, serve to remove many of the dis- ease-producing bacteria, as well as filth, and are all that are required to render a house ''''clean'''* in the hygienic sense of the word. 400 DOMESTIC HYGIENE. In cleaning a room occupied by persons suffering from contagious diseases these simple cleansing agents are usually reinforced by the use of more powerful germicidal substances. Such a room should first be disinfected with formaldehyd vapor^ applied either by means of a spraying apparatus or in the form of gas generated in a special apparatus (Fig. ro8). After Fig. io8.— Formaldehyd gas generator. the room has been disinfected by one of these methods, it should be cleaned by the free use of soap and hot soda solution. Washing and Laundering. — Under ordinary con- ditions the laundering of clothing has but little hygienic interest when the work is done at home. HOUSE-CLEANING. ■ 40I When cases of infectious diseases occur in the house- hold, the clothing of the sick persons should never be laundered with those of the remainder of the family. The clothing of the sick should be placed into a receptacle containing water and some anti- septic, such as carbol soap, before it is removed from the sick-room. When moistened in this manner, it may be removed from the sick-room, and after stand- ing in the antiseptic solution for several hours, may be washed in the ordinary manner. Clothes-cleaning. — Articles of wearing apparel and bed-clothing that cannot be cleaned by wash- ing require cleansing by other methods. When such articles have been exposed to infection, they should be disinfected by steam or with formaldehyd gas. Steam-disinfection requires a special appa- ratus, and consequently this cannot be carried out in the home. Disinfection with formaldehyd gas may be accomplished in the home. This may be done in several different ways, as by spraying the articles with a solution of formaldehyd, or they may be placed in a large closet which can be rendered air- tight and the formaldehyd gas generated in the closet with a Schering lamp, or the gas may be generated in an apparatus such as that represented in Fig. 108 and conducted into the closet through the keyhole. The last is the safer method, as the apparatus is under control and all danger from fire is avoided. Woolen clothes, blankets, bed-spreads, and furs should be cleansed at stated intervals. Besides the disinfection just described, such cleansing operations should consist of measures directed toward the re- 26 402 DOMESTIC HYGIENE, moval of grease and filth. Simple airing is insuf- ficient for satisfactory cleansing. Exposure to fresh air and sunshine is of great service in purifying such articles, but fails to remove grease spots. The latter should be removed with naphtha, benzin, or gasolin. Dirt and grease are freely soluble in those fluids, and they may be applied to delicate fabrics without detriment. These cleansing fluids may be applied with a sponge or cloth, or the articles may be immersed in the fluids. After having been cleansed in this manner the articles must be exposed to the air for some time to dry and allow the cleansing fluids to evaporate. After aeration for a day all odor of the cleansing fluids will have disappeared, and the articles are ready to be pressed with a hot sad-iron. When cleansed by this method and properly pressed afterward, the articles will appear almost like new and show no trace of the manipulation given them. It is necessary to be extremely cautious in the use of all these cleansing fluids, as they are highly inflam- mable. The cleansing operation should, therefore, always be performed in the open air, or at least in a room in which there is no light or fire. FOOD AND DIETETICS. The health of the household is dependent to a great extent upon the nature, quality, and quantity of the food-supply, as well as upon the manner in which the food is prepared. " Food is that which, when taken into the body, builds up its tissues and keeps them in repair, or which is consumed in the body to yield energy in the form of heat to keep it warm and create strength for its work." FOOD AND DIETETICS. 403 All the various elements and cliemic combinations of which the body is composed must be supplied in the food in order that it may perform its normal func- tions and obtain energy for the varied life-activities. A man of average weight and activity takes about 325 grams of dry solid matter and from 1500 to 2000 grams of water by the mouth, and about 550 grams of oxygen through the lungs each day. The solid matter taken as food should be composed of proteids or nitrogenous organic matter, of fats, and of carbohydrates. (See page 34.) A constant diet containing excessive amounts of any of the three elementary constituents, with or without deficiency of one or both of the other constituents, will in time prove injurious to health. In order to obtain the relative proportions of the elementary constituents required for nutrition we resort to a mixed diet. A deficiency in the elementary constituents of the food for a brief period is readily equalized by varia- tion in the diet on different days of the week. Custom has served to bring about a selection of a dietary which generally meets the requirements of the body. Nutritive Value and Cost of Food. — The follow- ing table (Table A.) shows the relative proportions of the elementary food-constituents in some of the more common food substances with the quantity that can be purchased for twenty-five cents, as well as the amount of energy that may be derived there- from. Table B shows the composition of the more com- mon cereals and leguminosae used for food based upon a large number of analyses. This table shows that these food-materials contain the elementary food-con- 404 DOMESTIC HYGIENE, Table A. — Nutritive Value a7id Cost of Food at Ordinary Prices. Food Materials as Purchased. Beef, sirloin Beef, round Beef, neck Mutton, leg Ham, smoked Salt pork Codfish, fresh Codfish, dried salt . . . Mackerel, salt .... Oysters, 25 cents a quart Eggs, 25 cents a dozen . Milk, 8 cents a quart . . Cheese, whole milk . . . Cheese, skimmed milk Butter, 25 cents a pound Sugar, 5 cents a pound . Wheat flour Wheat bread Oatmeal Beans Potatoes, 60 cents a bushel 12.5 14.7 Twenty-five cents will pay for- HE Grams. 500 780 1565 625 780 1250 1250 1565 1250 lOOO 850 3125 835 1250 500 2500 5000 2500 2500 2500 12,500 Nutrients. Total. Grams. 155 235 465 190 385 1045 135 255 370 120 190 385 545 675 430 2445 4350 1670 2260 3IIO 2135 Protein, Grams. 75 140 245 95 115 250 185 65 105 "5 235 480 5 550 220 370 580 225 Fats. Grams. 80 95 220 95 270 1035 125 295 Carbo- hydrat's Grams. 2445 3745 1410 1710 1480 1900 Fuel value. Calories. 970 1335 2755 1170 2705 8775 510 985 2275 520 1115 2030 3455 2910 3615 9100 6,450 6400 9225 8075 8000 Table B. — Analyses of Cereals and Leguminosce. Composition of the Cereals. No. of Nitrogen- Nitrogen- Cellu- lose. Cereal. anal- yses. ous sub- stances. Fat. free extrac- tives. Ash. gen. Per ct. Per ct. Per ct. Per ct. Per ct. Per ct. Wheat. . . 1358 13.89 2.20 79.75 2.19 1.97 2.22 Rye, winter ^17> 12.48 1.77 81.04 1.78 2.06 2.00 Barley . . . 766 11.24 1.93 77.24 4-95 2.42 1.79 Oats .... 377 12.13 4-99 66.41 10. S8 3.29 f.04 Corn, flint . 80 11.74 4.78 79.20 1.67 1.40 1.88 Rice . . . 10 7.00 2.00 84.76 4.00 1. 16 1. 12 Composition of the Leguminosce. No. of anal- yses. Nitrogen- ous sub- stances. Fat. Nitrogen- free extrac- tives. Cellu- lose. Ash. Nitro- gen. Beans . . . Peas . . . 63 72 Per ct. 29.26 26.39 Per ct. 1.68 1.39 Per ct. 55.86 61.21 Per ct. 8.06 5.68 Per ct. Per ct. 4.68 4.30 FOOD AND DIETETICS. 40$ stituents, expressed as nitrogenous substances, fat, and nitrogen-free extractives. The relative amount of these elementary constituents is such that exces- sive quantities of refuse matter and of carbohydrates must be taken to obtain the required amounts of pro- teids. This is the chief source of dissatisfaction with a true vegetarian diet — that is, a diet entirely of vegetable origin. Cooking. — Aside from the composition of foods, the modes of preparation are of the greatest hygienic importance. Cooking has two principal effects on food-materials : it softens the food so as to render it easier of mastication and digestion, and it also renders it more palatable. In addition to these alterations cooking also serves to destroy all bacteria that may be lodged in or upon the food, and in this manner renders it free from danger to health. The manner of cooking has a marked influence upon the digestibility of meats. The common modes of preparing meats are roasting, broiling, boiling, and frying. Roasted and broiled meats retain a large proportion of their juices, and are, therefore, more palatable as well as more nutritious. Boiling extracts the juices from the meat and consequently alters their nutritive qualities as well as their palatability. Fry- ing in fats and oils causes the meat to be unusually rich in fat, and, in consequence, more difficult of digestion. The purity of the food-materials is of equal importance with their quality and quantity. Foods may be adulterated in several different ways, as by the abstraction of some of the most valuable ingre- dients and the substitution of inferior or inert sub- 406 DOMESTIC HYGIENE, stances, and by the addition of various preservatives intended to prevent or retard decomposition. Preservation of Food. — In order to conserve food so as to make it available at all seasons of the year, a variety of methods of pres- ervation have been devised. Drying, canning, refrigeration, and t^e use of chemicals are the processes most commonly employed. Drying aids in preserving food, since the bacteria which might de- compose it require a certain amount of moisture in order to grow and, if the drying has been carried to the point where insufficient moisture remains, the bacteria cannot attack the food. In canning of food materials, we endeavor to kill all the bacteria in or on it and then hermetically seal the container so as to prevent the entrance of bacteria. - Refrigeration aims to keep the food materials at a temperature so low that bacteria are prevented from developing. The temperature is, however, not sufficiently low to prevent bacterial action, and hence foods preserved in this way may undergo slow changes which are not desirable or may even prove injurious. The use of chemicals for the preservation of food materials has the object of increasing the salt-content so as to prevent the devel- opment of bacteria, or chemicals are sometimes used which act as poisons to the bacteria. All chemicals of the latter class, such as benzoic acid, salicylic acid, boric acid, formaldehyd, sulphites, etc., are also injurious to human beings and should not be used as food- preservatives. The adulteration and preservation of food is more fully discussed in a special chapter (p. 431)- Food may cause infectious diseases from the presence in it of specific bacteria or parasites. Mi/k may contain tubercle bacilli when derived from tuber- culous cows, or it may contain pus-producing organisms (streptococci) when there is catarrh or inflammation of the udder. Milk may serve as the carrier of other disease-producing bacteria by the accidental entrance of such organisms as the bacillus of diphtheria, the bacillus of typhoid fever, the bacillus of dysentery, or the cholera organisms. These organisms usually gain access to milk by the addition of polluted water or by rinsing and washing the containers with such polluted water. Milk may also serve as the carrier of scarlet fever when this disease prevails in the family of the milkman or dairyman. Butter may serve as the carrier of disease in much the same way as milk. FOOD AND DIETETICS. Af:i'J Meat may contain the organisms of tuberculosis as well as the ova and larvae of animal parasites, as trichina, cysticercus, etc. For these reasons meat should never be eaten in the raw state. Green vege- tables may serve as the carriers of disease when they are raised in ground fertilized with night-soil. Let- tuce may also convey typhoid fever or the ova of animal parasites when raised on such ground. Oysters are now recognized as frequent carriers of the bacillus of typhoid fever, on account of having been freshened in sewage-polluted streams. Inspection of Foods. — The dangers from infected meat and milk and from adulterated foods in general can be overcome only by the most rigid sanitary inspection. These are conditions which the individ- ual cannot control altogether. The inspection of meats should include not only the routine slaughter-house inspection, but should also include rigid inspection of the meat exposed for sale in markets and shops. A great deal of the danger arising from the consumption of diseased and putrid meat can be avoided by such inspection. In this connection a committee of prominent physicians and veterinarians has recently made the following recom- mendations to the health authorities of Philadelphia : ''First: All meat inspected by the meat-inspector should be stamped. *' Second : The hours for slaughtering should be regulated, and butchers should be prohibited from killing animals at timts other than those fixed. ''Third: All slaughter-houses should be visited by the meat-inspectors during the hours of slaughtering, and all the carcasses should be examined, and those found to be in a con- dition suitable for food should be stamped. " Fourths Beef prepared in the surrounding country and 408 DOMESTIC HYGIENE, brought into the city in wagons should be brought in only at certain specified times, and before unloading the wagon should pass a certain inspection-point where the meat could be ex- amined by an inspector stationed for this purpose, and stamped if found to be in sound condition. '' Fifth : The meat-inspection force should be increased by the addition of a sufficient number of veterinarians. ** Sixth : Sanitary regulations should be established govern- ing certain features of the construction, fittings, and care of slaughter-houses, and all slaughter-houses falling below a rea- sonable standard should be proceeded against as a nuisance." The committee also believes that there should be fewer slaughter-houses and more inspectors. In Paris there are 70 inspectors and only 2 abattoirs. In Ber- lin there are 150 inspectors and only i abattoir. In Philadelphia there are more than 100 slaughter-houses and but 5 inspectors. The inspection of milk as practised in most muni- cipalities fails to accomplish all that might be accom- plished in this direction. The municipal inspectors rarely possess the authority to extend their supervision of the milk-supply beyond the limits of the muni- cipality. Systematic inspection of dairies and milk- shops as to manner of production and storing of milk will accomplish a great deal. The licensing of all milk-dealers has served a useful purpose. The proper care of milk in the household is often neglected. Milk should be purchased in sterilized bottles and should be removed from these containers only when it is to be used. Milk should be placed on ice as soon as delivered, so as to prevent the too rapid develop- ment of bacteria in it. The recent suggestions of a Medical Milk Com- mission appointed by the Director of Public Health of Philadelphia are as follows : FOOD AND DIETETICS. 409 1. That all milk-sellers be required to obtain a license, and that such license be granted free of charge. 2. That no license be issued unless the dealer is willing to state the source of his supply, and to give satisfactory evidence that the producer from whom he receives his milk maintains his herd and premises up to the standard prescribed by the Department of Public Health ; observance of such standard to be determined by periodic inspections under the direction of this same department. 3. That the standard to be established should correspond closely or exactly to the list of fifty dairy rules recommended by the Bureau of Animal Industry of the United States Department of Agriculture. 4. That dealers be required to remove all milk from the transportation trains immediately upon their arrival, unless in refrigerator cars, and to deliver the milk of the morning and previous evening on the day of its arrival, unless kept iced. 5. That dealers be required to have a special milk-room so situated in relation to their houses as not to be a thorough- fare. That its walls shall be tiled or painted with a glazed paint ; that its floors be made of hard wood, cement, or other composition, or that they shall be covered with linoleum ; that the room shall be well ventilated and kept thoroughly clean. 6. That it be required that all milk-wagons be thoroughly cleansed after each delivery, and that they be so constructed that thorough cleansing is possible. That all utensils, such as dippers, etc., carried on milk-wagons, when not in use, be kept in separate clean cans. 7. That no dealer or producer be permitted to deliver milk in bottles who has not on his premises satisfactory appliances for the proper cleansing and sterilization of bottles and who does not properly use them. 8. That no dealer be permitted to fill bottles outside of his own milk-room. That dealers should be required thoroughly to cleanse and scald all milk-cans before returning them to the producer. In conclusion, the Commission says : "■ In addition to the tests which are at present applied by the Inspectors of Milk we would suggest that, in order to obtain some idea of the bacterial contents of the milk, the degree of acidity of the milk be determined and that all milk 4IO DOMESTIC HYGIENE. showing an acidity of more than 0.2 per cent, be condemned. That an examination by sedimentation be made to determine the amount of dirt per cent., and if found in more than a minimum quantity, that such milk be condemned. " Any dairyman or dealer who is incapable of meeting such requirements should not be permitted to produce or sell milk. ' ' Pasteurized Milk. — In recent years the use of pas- teurized milk has become quite general, since it is evi- dent that raw milk is frequently responsible for the dissemination of disease. Pasteurization consists in heating the milk to from 140 to 160° F., so as to kill disease-producing bacteria that may have gained en- trance to it. Pasteurized milk is not sterile, and does not keep longer than twenty-four to forty-eight hours. CAUSES AND TRANSMISSION OF DISEASE. The piiysical causes of disease are such physical agents as heat or cold, excessive or deficient humidity of the air, contusions, wounds, accidents, dust, and winds. Changes in barometric pressure, as in balloon- ascensions or in mountain-climbing, where the air is rarefied, and in work in deep mines, where the atmo- spheric pressure is increased, may prove injurious. The vital causes of disease are the different species of bacteria and vegetable and animal para- sites. The bacteria cause disease by the production of virulent poisons which are destructive to the blood-cells and tissue-cells. The animal and vege- table parasites cause disease through the destruction of the blood-cells and tissue-cells, by the absorption of nutritive materials, and by the obstruction of im- portant tissues and organs. The chemic causes of disease are the numerous chemic substances which are destructive to the tissues with which they come in contact. Transmission of the infectious diseases may be effected in a variety of ways : By drinking-water, CAUSES AND TRANSMISSION OF DISEASE. 4II food, air, soil, wounds, direct and indirect contact, and throuo;h the aorencv of insects. The diseases which are transmitted by driiiking-zvater and food are those which have their primary seat in the diges- tive tract. The diseases which are transmitted through the air are those affecting the respiratory tract. The eruptive fevers may also be transmitted through the air. The diseases which are most likely to be transmitted through the soil are tetanus and malignant edema, and the organisms causing these diseases are usually introduced into the body through punctured or incised wounds or through abrasion. Many diseases are probably largely transmitted by contact, direct or indirect. Indirect contact may take place through the agency of anything that has been used or handled by the person suffering from the disease, as clothing, cups, napkins, handkerchiefs, money, books, etc. Insects and vermin may serve to transmit disease either directly or indirectly. Examples of the direct transmission of the organisms of disease by means of insects are the transmission of malaria, yellow fever, and filariasis through the agency of certain species of mosquitos^ the transmission of relapsing fever through the agency of bedbugs, of typhus fever by the body louse, and of plague by the rat-flea. The indirect transmission of disease by insects occurs when the insects, such as flies, cockroaches, and bedbugs, become contaminated with the germs of disease, and carry the infective agents on their bodies to food or to other persons. The influence of flies in the dissemination of dis- ease had not been fully appreciated until a few years 412 DOMESTIC HYGIENE. ago. Flies alight on all kinds of filth and soil their wings and feet, and may subsequently carry the disease-producing bacteria to food materials. In this manner disease may be disseminated over considerable areas. Consequently, for distinct san- itary reasons, flies, as well as mosquitoes, should be excluded from houses by means of mosquito- netting. When flies have gained access to the house there are several ways in which they may be attacked, as by "swatting," by the use of * 'sticky" fly-paper, or by using fly -poison. Fly-poisons should be non-poi- sonous for man. The use of arsenical preparations should be prohibited because fatal poisoning of chil- dren has been traced to these preparations. The safest fly-poisons are formaldehyd in the propor- tion of three teaspoonfuls to a pint of water, or sodium salicylate in the proportion of three tea- spoonfuls to a pint of water. Neither of these solu- tions would be dangerous to children and may be re- garded as safe and efficient muscicides. Similarly, fleas should also be destroyed or ex- cluded. The tick is thought to be directly or in- directly instrumental in the transmission of the "spotted fever" of Idaho and Montana. Rats are concerned in the dissemination of plague and other diseases, though this relation is an indi- rect one, since it has been demonstrated experiment- ally that the actual dissemination of plague is by the "rat-flea." Rats are susceptible to the plague- infection, and when they die the fleas which they har- bored through life leave the dead body and may then attack man and infect him. Plague is, therefore, CAUSES AND TRANSMISSION OF DISEASE. 413 transmitted from rat to rat and from rat to man through the agency of the rat-flea. All vermin should, therefore, be excluded from houses, and when they have gained access, they should be exterminated as speedily as possible. Vermin of this character are found most frequently in filthy loca- tions, and hence cleanliness is the best safeguard against vermin as well as against the diseases which they may disseminate. The Prevention of Disease by Isolation and Disinfection. — By means of isolation the infective materials are confined to the immediate vicinity of the patient, and by means of disinfection, the infective materials are rendered harmless. The discovery of the specific causes of disease and the avenues by which they are thrown off from the body have simpli- fied our efforts to limit the dissemination of disease through disinfection. In the diseases of the alimentary tract, as in typhoid fever, dysentery, and cholera, the infective agents are thrown off* with the intestinal evacuations and the urine, and it is to these evacuations that we must apply the disinfective materials. In diseases of the respiratory tract, as in influenza, pneumonia, pulmo- nary tuberculosis, diphtheria, mumps, and whooping- cough, the sputum contains the infective agents, and must, therefore, be disinfected. In these diseases the sputum should be collected in sputum-cups or paper napkins, which can be disposed of by burning them. In the eruptive fevers, as in small-pox, scarlet fever, and measles, the infective materials are believed to be given off" principally through the desquamating epithelium, the discharges from the skin lesions in 414 DOMESTIC HYGIENE. small-pox, and the discharges from the ears, nose, and throat. The individual susceptibility to infection varies greatly. The degree of susceptibility is dependent principally upon the general physical condition of the individual, upon his environment, and upon hereditary influences. A lozvering of the genei^al physical tone^ from whatever cause, predisposes to in- fection. So long as the physical condition of the body is maintained in the normal state, infection does not readily take place. It is safe to assume that all of us are more or less frequently exposed to different in- fective agents, which fail to gain a foothold in our bodies because of the normal vital resistance. En- vironment plays an important part in predisposing to infection. This may operate by inducing a lowered vitality of the body, as well as by the more frequent and intimate contact with infective materials in places that are overcrowded, as street-cars, schools, and other public assemblies. The influence of environ- ment is brought out very well in the investigations of Anders and Flick, of Philadelphia, and Park, of New York, on the prevalence of tuberculosis in cer- tain houses. These investigations have shown that the disease is most prevalent in houses in which pre- vious cases have occurred. Heredity plays an im- portant role in the individual susceptibility to dis- ease. The peculiar constitutional states which we inherit predispose to special types of infection. This is seen in the greater susceptibility to certain diseases in one family than in another. The influence of heredity is seen more particularly in the prevalence of CAUSES AND TRANSMISSION OF DISEASE. 415 certain constitutional diseases, although it is believed to be an important factor in predisposing to diseases like tuberculosis and rheumatism. Hygiene of the Sick-room. — When infectious disease appears in the household, the patient should be isolated in a large airy room on the upper floor, which is removed as far as possible from the other occupants of the house. The upper floor of the house is to be preferred, because it is further removed from annoyance by street-noises and street-dust. All well persons, with the exception of the physician and nurse, should be rigidly excluded from the room. The other occupants of the house should be prohibited from attending any school or other public assembly. A moistened sheet suspended in front of the door of the sick-room will serve to arrest most of the infectious dust-particles. The room itself should be furnished as simply as possible ; all unnecessary furniture, as well as carpets and curtains, should be removed. No sweeping should be allowed in such a room. The nurse should wipe all horizontal surfaces with a damp cloth each day. The clothing and bed-clothing should be placed in carbol-soap solution before they are re- moved from the room. The sick-room should be supplied with a gas-stove and a small boiler, in which napkins, eating utensils, etc., may be disinfected with boiling water before removal from the room. The food that is not consumed by the patient should always be burned. After the recovery of the patient the room should be closed for some hours to allow all dust-particles to subside. It should then be fumigated or disinfected. 4l6 DOMESTIC HYGIENE. after which it may be cleaned in the usual manner. with hot soda solution, chlorid-of-linie solution, or some of the stronger disinfectants, as 2 or 3 per cent, carbolic-acid solution. All toys and other articles of little value which have been in the room should be wrapped in a sheet moistened with solution of chlorid of lime or carbolic acid and afterward burned. Books that have been in a sick-room should always be disin- fected before they are again used. This is usually done by means of formaldehyd gas. House-quarantine is instituted by the authorities of cities and towns against a number of infectious diseases, the custom varying somewhat in different places. The diseases against which quarantine is usually practised are : cholera, small-pox, diphtheria, diphtheric croup, membranous croup, scarlet fever, typhoid fever, typhus fever, plague, epidemic cerebro- spinal fever, relapsing fever, and leprosy. The length of time during which quarantine is necessary differs with each disease : in some, the period is fixed arbi- trarily ; in others, as in diphtheria and diphtheritic croup, quarantine is maintained until cultures from the patient's throat show the absence of the specific bacteria. In the eruptive fevers, as scarlet fever and measles, quarantine is continued until desquamation has ceased. Table C shows the carriers of the infec- tion, the period of incubation, the period of desqua- mation, the point of entrance of the infectious agent, the excretions which are infective, the cause, the special prophylactic measures, and the preventive measures of the principal infectious diseases. The length of time during which well persons should be detained in quarantine after exposure to CAUSES AND TRANSMISSION OF DISEASE. 417 the different infectious diseases which might be car- ried by them, is shown in the following table : Periods of Isolation of Well Persons after Exposure to — Diseases. Days. Small-pox 14 Measles 10 Scarlet fever 3 Diphtheria 3 Cholera 10 Typhoid fever 14 Yellow fever 5 Chicken-pox 20 Mumps 24 Whooping-cough 21 Infantile paralysis 28-42 This period of detention varies in the different dis- eases because of the varying lengths of their respective periods of incubation. After the period of incubation for a particular disease has passed and no new cases have developed, the persons in quarantine may be released. Special Precautions against Typhoid Fever. — The following is an open letter relative to the preven- tion of typhoid fever, issued to the citizens of Phila- delphia by the Bureau of Health : Typhoid fever is caused by a tiny germ that gets into the body of the sick person, usually by way of the mouth, and that escapes from the body with the discharges from the body. The discharges are, therefore, to be regarded as dangerous. These matters may easily be rendered harmless by scalding them with boiling water or by the use of any of the reliable disinfectants, especially chlorid of lime. Such matters should always be disinfected before being thrown away. When discharges from typhoid patients are thrown into wells or strewn upon the ground or into sewers, the germs do not die at once, but remain alive for varying lengths of time, and when spread about, may cause an outbreak of the disease. 27 dl DOMESTIC HYGIENE. ^ ^ ^ ^ 'o .^ o < ^ n! 3 .5 OB .5 2c«i (n •— nl !5 "s"^ '.£ w 2|| 5) 'O .s;-o -5 'c'o XI 4) ui -a c'-o 3 §^ -a ^^•^ •S Si cj 2 ; 2 3 cS ; "^ .S^'' fS 3 ; ; E u"^ ti 3 C C 'rt'^ c' 3 3' 3 3 3 •2 5= 3 c 2.2 000 >< 3 c *^ ca u c -. c.o > — 3 c -n 3 3 rt u 2 rt u •S c rr .!> D -— 1) •" rt 11 T .U >• C*- cJ '-S -. o<« 3 — Ci ■J^ rt 'S 'Z! Dh U) > U) <: ^ K 6 « 3 • ^ ? .2.2 Pnii C* S . 11 s 1^ " > <: i 1 • 1". c c .2.2 •o c rt jj 2 c C"S E ' 6 3 3 3 : o§ -r 11 c s 3 %\ ^ rt <5W 5 x" P •5 1§ 1*, f^ 0.2 (fl tn"*- m ^J u « •5:1 E .■3 IJ rt 6 b fc t .i 6 . ^ T _o > rt >. tn 'u ^ ■5 > Ql. '7, ■" 3 3 S 5 - ?! S tn -3 H.3 3 3 fe H 4 U g u u u B- cn 3 3 a I in - i " 3 a-5 in s° i: '^ 3 ^ ^ n! rt in c< c« ^3 U U3 ^ mm M S M m M JS bo j; X 3 «; < Q > 1 a . .u a! ^ S 1 i E 3 Ji 3 3 .5 3 E S 3 Pi "1 3 H p. tx CAUSES AND TRANSMISSION OF DISEASE, 419 , ■w <*-. c C 4) *'0 s So n.2 rt '3 «• •T3 C * » .. , ... . 5-^ 3 '3 C C ^ c B .y.2 bil ^ •Sfi T3 -o'A ~ 1^ C s ^ i^ '^ u a g k g — c t;!.2 4i u iS^^s ^^ ^0 -pe P3 Ph Ph Ph u ^ 04 .at C/2 3 Oh c fD ir ■< w VO 1 >. 10 > VO p 0^ CJ (N ro H ro <; Q Jo.^ ci <^ vi B C a B fl ?es!a, but not potash or soda; ( then soothing drinks. Fresh air; ammonia to nostrils; cold douche ; artificial respiration. Emetic, followed by digitalis; no pillow under head ; free stimulation. Emetic ; cold douche on head ; warmth and artificial respiration. Vinegar or lemon-juice, followed by sooth- ing drinks or sweet oil. Emetic if vomiting is not already profuse ; then tannic acid freely or strong tea ; ler, milk or other soothing; drinks at finally castor oil to empty the bowels. Emetic, quickly followed by plenty of a fresh mixture of the tincture of chlorid of iron with calcified magnesia, washing- or baking-soda, or water of ammonia, or by JeauneV s antidote. Then white of egg, soothing drinks, or sweet oil ; castor oil to empty bowels. Atropin (see Belladonna). Belladonna (atropin) . ( Emetic ; tannic acid freely ; cold to head ; \ coffee. Stimulants and warmth if needed. Blue stone ; blue vitriol (see Copper). Treatment as for opium-poisoning. ' Cold douche ; friction of skin ; inversion ; artificial respiration. Emetic, followed by white of egg or milk, yellow prussiate of potash ; then soothing drinks. Chloral . . Chloroform inhaled. Copper (blue stone vitriol ; verdigris). blue Corrosive sublimate Emetic, followed by white of egg or milk; soothing drinks; tannic acid freely; castor (^ oil to open bowels. Cyanid of potash (see Acid, prussic). Fowler's solution (see Arsenic). Gas (illuminating gas, coal- f Fresh air ; artificial respiration ; ammonia gas). I to nostrils ; cold douche. mixed with water, given soothing drinks. T^j- f Starch or flour iodm < r , -^ ^. \ freely ; emetic i 526 APPENDIX, Laudanum (see Opiuni). Lead (sugar-of-lead) . . . Matches (see Phosphorus). Morphin (see Opiutn). Nux vomica (see Strychnin). Opium (including lauda- num, morphin, paregoric, soothing syrups, etc.). Emetic, followed by Epsom salt , egg or milk ; alum. white of Paregoric (see Opium). Paris green (see Arsenic). Phosphorus (match-heads, | some roach and rat poi- -J sons). j Poisonous plants (Jimson f weed, poisonous mush- } rooms, deadly night- j shade, tobacco, etc.). [ Prussic acid (see Acid, prussic) Silver nitrate (lunar caustic). ] Spoiled food ] Strychnin (nux vomica) . Tartar emetic (see Antimony^. Emetic (but generally useless) ; permanga- nate of potash in doses of 4 or 5 grains if case is seen early ; strong coffee ; atropin ; keep patient awake and breathing by cold douche to head and spine, walking, etc., but not to extent of exhaustion ; artificial respiration. Emetic ; then permanganate of potash in doses of 4 or 5 grains well diluted ; then Epsom salt or magnesia to open bowel, but no milk or oil of any kind. Emetic, followed by tannic acid ; strong coffee or brandy ; ammonia to nostrils ; external warmth; artificial respiration. Table-salt, followed by emetic; milk or white of eggs. Emetic, followed by castor oil as a purga- tive. Emetic, followed by tannic acid, bromid oj potash freely, or chloral. GLOSSARY. Abdomen. The belly. Abdominal. Pertaining to the belly. Accommodation. Adjustment of the eye for various distances. Adenoid. A tumor composed of glandular tissue. Advancement. Detachment of an eye-muscle and reattachment at an advanced point. Aeration. Purification by expo- sure to air. Afferent. Passing or conducting from the periphery or the nerve- center. Albinism. A congenital deficiency of coloring-matter in the skin, hair, etc. Alimentary canal. The entire digestive tract from the mouth to the anus. Alveolus. A small hollow, as a socket of a tooth. Amblyopia. Dimness of vision. Ametropia. Imperfection in the refraction of the eye. Anemia. Deficient quantity or quality of the blood. Aneurysm. A sac formed by the dilation of part of an artery and filled with blood. Anisometropia. Marked inequal- ity in the refractive power of the two eyes. Antiseptic. A substance that destroys germs. Antrum of Highmore. A cavity in the upper jaw, communicating with the nose. Anus. The external opening of the lower bowel (rectum). Appendix. See Vermiform ap- pendix. Aqueous humor. A watery fluid occupying that portion of the eyeball between the cornea and the crystal- line lens. Arcus senilis. A whitish ring occurring on the cornea, particularly in the aged. Arytenoid cartilages. Two carti- lages at the back of the larynx. Aspergillus. A genus of fungi (moulds). Asphyxiation. The act of caus- ing suffocation. Asthenopia. A weakness and speedy tiring of the visual apparatus. Astigmatism. A defect of the eye in which the Hght-rays are not brought to a proper focus. A point of light is seen as a star. Atrophy. A wasting away of a part. Auditory canal. The passage that leads from the external ear to the ear-drum. Auditory nerve. The nerve of hearing. Auricle, i. The external ear. 2. 527 528 GLOSSARY. The two upper chambers of the heart. Aurist. Specialist in ear-diseases. Auto-intoxication. Poisoning by some toxic or effete substance formed within the body. Axilla. The armpit. B Binocular vision. Normal simul- taneous use of the eyes. Blepharitis. Inflammation of the edges of the eyelids. Bronchi. The two main branches of the windpipe (trachea). Canaliculus. A small canal, as the lacrimal canaliculus, through which the tears drain into the nose. Canthus. The angle at the junc- tion of the eyelids; the "corner of the eye." Capillary. Any one of the hair- like vessels which conduct the blood from the arteries to the veins. Capsule of Tenon. The sheath enveloping the eyeball. Cardia. The opening of the esophagus (gullet) into the stomach. Caries. Decay of bone; dental caries, decay of teeth. Cartilage. Gristle. Cataract. Opacity of the crystal- line lens of the eye. Cecum. The upper part of the large intestine. Cement. The hard layer cover- ing the root of a tooth. Central nervous system. Brain and spinal cord. Cerebral anemia. Deficient blood-supply to the brain. Cerebrum. The brain proper. Cerumen. Ear-wax. Cholesteatoma. An encysted tumor containing cholesterin. Choroid. The coat of the eyeball containing the blood-vessels. Choroiditis. Inflammation of the choroid. Chyme. Food which has under- gone digestion in the stomach. Cilia. I. Eyelashes. 2. A small lash-like process. Ciliary body. The pigmentary coat of the eye. Ciliated epithelium. Epithelium provided with small hairs constantly in motion. Clavicle. Collar-bone. Colon. The middle part of the large intestine between the rectum and the cecum. Coma. Morbid sleep or uncon- sciousness, as the uremic coma of disease of the kidneys. Commissure. The Hne of junc- tion between two similar intersecting surfaces, as commissure of the eye- hds. Compress. Folded cloth for apply- ing pressure. Cones. Cone-shaped bodies of the retina. Conjunctiva. Membrane which lines the eyelids and covers the eye- ball. Conjunctivitis. Inflammation of the conjunctiva. Cornea. The transparent front part of the eyeball. Cortical centers. Nerve-centers of the cerebrum (brain proper). Costal cartilages. Cartilages which prolong and attach the ribs to the breast-bone (sternum). GLOSSARY. 529 Cribriform plate. Tne upper per- forated plate of the ethmoid bone. Cricoid cartilage. The lowest cartilage of the larynx. Crystalline lens. The transparent lenticular organ behind the pupil. Curarization. Muscular weak- ness and paralysis similar to that produced by a drug called curare. Cuticle. The outermost layer of skin. Cyanosis. Blueness of skin or other tissues. Cycloplegia. Paralysis of the ciliary muscle of the eyeball. Dacryocystitis. Inflammation of the tear-bag. Deglutition The act of swallow- ing. Dejecta. The waste matter passed from the bowel ; the feces. Dentin. A brittle substance form- ing the main part of the tooth. Depilatory. Having the power of removing hair. Derma cutis. The true skin ; the skin underneath the epidermis. Dermatologist. A specialist on diseases of the skin. Desquamation. Shedding of the skin. Diabetes. A disease marked by an excessive secretion of urine, gen- erally loaded with glucose (sugar). Diaphragm. The partition which separates the chest from the abdomen. Diathesis. Predisposition to dis- ease. Diplopia. The seeing of single objects as double. Douche. A stream of water or other fluid directed against a part. 34 Duct. A tube through which the secretion of a gland empties. Duodenum. The first part of the small intestine, beginning at the stomach. Eflleurage. Centripetal stroking movement in massage. Elastic fibers. Fibers that com- pose tissue capable of returning to its proper shape after compression or stretching. Emetic. A substance that causes vomiting, as ipecac. Emmetropia. Perfect visual re- fraction ; normal vision. Emphysema. Abnormal disten- tion of tissue by air or gas, generally applied to distended lung tissue. Enteroptosis. A downward dis- placement of the intestines. Entropion. Turning in of the eye- lids or eyelashes. Enucleation. Removal from an envelope. Enucleation of the eye- ball is the cutting out of that organ from its membranous envelopes. Epidermis. The outermost layer of skin. Epiglottis. The lid of the larynx. Epiphora. Overflow of tears. Epistaxis. Bleeding from the nose. Epithelium. The outer and blood- less layer of mucous membranes and of the skin. Erectile tissue. Spongy tissue that becomes hard when expanded with blood. ErgOgraph. Instrument for measuring work done by muscular action. Esophagus. The canal which car- 530 GLOSSARY. ries the food from the throat into the stomach. The gullet. Etlimoid bone. A sieve-like bone of the nose. Eustachian tube. One of two canals leading from the back of the nose to the drum of the ear. Exantbematous. Characterized by an eruption or rash. The exan- themata are the rash-diseases, such as measles, chicken-pox, scarlet fever, etc. Excrescence. A morbid growth projecting from a surface. Exostosis. Abnormal outgrowth from surface of bone. Extravasation. The escape of any fluid from its proper vessel into the tissue. Fauces. The communication be- tween the throat and pharynx. Feces. Refuse material expelled from the bowels through the anus. Fibroid phthisis. Interstitial pneumonia ; chronic bronchitis. Fossa. A pit, depression, or hol- low. Fovea centralis. Pit in middle of macula lutea ; the sight-center of the retina. Frontal bone. The bone of the forehead. Gastric juice. The digestive fluid secreted by the stomach-glands. Gastro-intestinal tract. The stomach and intestines. The bowels or gut. Qenito-urinary. Pertaining to the genital and urinary organs. Germicide. An agent that de- stroys microbes. Glands. Small organs occurring in different parts of the body and secreting fluids. Glaucoma. Excessive pressure within the eye, leading to partial or complete blindness. Hardening of the eyeball. Glottis. Aperture between the vocal cords. Glucose. Grape-sugar, found nor- mally in the animal body and abnormally in the urine in diabetes (glycosuria). Glycogen. A carbohydrate from liver and other tissues. H Hair-follicle. The small depres- sion in the skin from which each hair grows. Hard palate. Front part of the roof of the mouth. Hematemesis. Vomiting of blood. Hematoma. A tumor containing blood. Hemoglobin. The coloring-mat- ter of red corpuscles of the blood. Hemoptysis. Spitting of blood coming from the lungs, as in phthisis or consumption of the lungs. Hepatic. Pertaining to the liver. Heterophoria. Absence of paral- lelism between visual fields. Ab- normality of ocular muscle-balance. Holophane. A lamp-globe formed of prisms to deflect the Hght rays downward. Humor. Any fluid or semifluid of the body. Hutchinson teeth. A character- istic condition of the teeth seen in hereditary syphilis. GL OSSAR Y. 531 Hydrotherapy. Treatment of dis- ease by means of water. Hyperopia. Far-sightedness. Hyperostosis. Excessive growth of bone. Hypertrophy. Enlargement of a part. Hypochondriasis. A mild form of melancholia. I Ileocecal valve. Valve at the junction of the small and large in- testines. nemn. The last portion of the small intestine, joining the cecum. Immunity. The condition of being protected against any particular dis- ease, as from small-pox by vaccina- tion. Incubation. The period between the implanting of an infectious dis- ease and its manifestation. Insalivation. Saturation of food with saliva during mastication. Insomnia. Inability to sleep. Interstitial tissue. The con- nective tissue between the cellular elements of the body. Intestine. That part of the ali- mentary canal extending from the stomach to the anus. The bowel or gut. The first portion is the jwa// intestine ; the second, and larger, is the large intestine. Iridocyclitis. Inflammation of the iris and ciliary body. Iris. The pigmented membrane behind the cornea, perforated by the pupil. Iritis. Inflammation of the iris. Isthmus of fauces. The pas- sage connecting the mouth and pharynx. Jejunum. That portion of the small intestine between the duode- num and the ileum. K Keloid. A tumor of the skin. Kyphosis. A fore-and-aft bend- ing of the spine. Hunchback. Labyrinth. A term applied to the internal ear. Lacrimal glands. The glands which secrete the tears. Lacrimal sac. The tear-bag. Laryngitis. Inflammation of the larynx. Laryngopharynx. The lower portion of the pharynx. Laryngoscopic mirror. A mir- ror used to examine the larynx. Larynx. The organ from which the voice-sounds proceed. Lens-capsule. A transparent sac that encloses the crystalline lens of the eyeball. Leukocyte. A white blood-cor- puscle. Ligament. A tough band con- necting bones or supporting organs. Lobule. A small lobe. Locomotor ataxia. A disease affecting the spinal cord, character- ized by partial paralysis and a pecu- liar gait. Lunula. The crescentic whitish area near the root of the nail. Lymphatics. Small vessels per- vading the body and containing lymph. 532 GLOSSARY. M Macula lutea. The point of clearest vision at the center of the retina; the yellow spot. Malleus. A mallet-shaped bone of the middle ear. Mariotte's blind spot. The spot on the retina where the optic nerve enters. Mastoid. The mastoid or nipple- shaped process of the temporal bone behind the external ear. Meatus auditorius. The passage that leads from the external ear to the ear-drum. Mechanotherapy. Treatment of disease by mechanical means, as rubbing, massage, bending, etc. Meibomian glands. Oil-secret- ing glands of the eyelids. Membrane. A thin layer of tissue covering a surface or dividing an organ. Metabolism. The process by which the body-tissues are renewed and nourished. Micturition. The passage of urine ; urination. Miotic. A drug which contracts the pupil, as eserin. Mucus. The secretion from mu- cous glands. Musc» VOlitantes. " Floating flies." Specks seen as floating be- fore the eyes. Mydriatic. A drug that dilates the pupil, as atropin (belladonna). Myopia. Near-sightedness. N NarcotiS. A drug that produces sleep or stupor and relieves pain, as opium. Nares. The chambers of the nose. Nasal duct. The duct that conveys the tears from the tear-bag into the nose. Nasopharynx. The part of the pharynx above the soft palate. Neurasthenia. Nervous prostra- tion. Neuritis. Inflammation of a nerve. Neuromuscular system. The system of muscles and their nerves. Nystagmus. Continuous move- ment of the eyeball, horizontally or rotary. Olfactory. Pertaining to the sense of smell. Ophthalmia neonatorum. In- flammation of the outer membranes of the eyeball in the newborn. Ophthalmoscope. An instrument for examining the interior of the eye- ball. Orbit. Bony socket that contains the eyeball. Oropharynx. The lower part of the pharynx, which communicates with the mouth. Ossicle. A minute bone ; any one of the small bones of the ear. Otorrhea. A discharge from the Palate. The roof of the mouth. There is a hard and a soft palate, which see. Pantoscopic spectacles. Bifocal glasses. Papilla. A small nipple-shaped elevation. Paresis, i. General paralysis, a. Incomplete motor paralysis. GLOSSARY. 533 Parotid gland. One of the glands which secrete saliva. Pathogenic. Causing disease, Penicillium. A genus of mould- fungi. Peridental membrane. The membrane covering the cement of the tooth. Periosteum. The membrane in- vesting bone. Peritoneum. The membrane which lines the abdominal walls and invests the abdominal organs. Petrissage. Kneading action in massage. Peyer's patches. Whitish patches of lymph-follicles in the small intes- tine. Pharyngeal tonsil. A small body situated in the vault of the pharynx. Pharynx. A musculomembran- ous sac lying behind the mouth and opening below into the esophagus. Photometry. Measurement of the intensity of light. Photophobia. A dread of light. Phthisis. Consumption of the lungs. Pigment. Coloring-matter. Pillars of fauces. Folds of mu- cous membrane at the sides of the fauces. Pinguecula. Yellowish spots on the conjunctiva. Plantar ligaments. Ligaments of the sole of the foot. Plastic operation. An operation for repairing injuries or deformities by forming new parts from surround- ing tissue. Plethora. A state characterized by swelling of the blood-vessels, due to excess of blood. Plethysmograph. An instrument for measuring variations in size and blood-supply of a part. Pleura. The serous membrane in- vesting the lungs and lining the thorax. Plexus. A network of blood-ves- sels or nerves. Polyps. Small growths from a mucous surface, as nasal polyps, uter- ine polyps, etc. Presbyopia. Impairment of eye- sight due to hardening of the crystal- line lens in advanced life. Process. A prominence, espe- cially on a bone. Prophylaxis. Preventive treat- ment. Protoplasm. The essential con- stituent of the living cell. Pruritus. Itching. Pterygium. A fleshy growth on the conjunctiva. Pubes. The hair on the external genitalia, or the region covered with it. Pulmonary tuberculosis. Con- sumption of the lungs. Punctum lacrimale. An orifice on each lid leading into the lacrimal canaliculus and tear-bag. Pupil. The opening in the center of the iris. Purulent. Containing or consist- ing of pus. Pylorus. The opening of the stomach into the small intestine. Pyorrhoea alveolaris. Inflam- mation of the dental periosteum^ with discharge of pus. Rachitis. A disease in which the bones become softened and de- formed; rickets. 534 GLOSSARY, Rectum. The lower part of the large intestine. Regurgitation. The casting up of food just swallowed. Rete mucosum. The innermost layer of the outer skin. Retina. The perceptive membrane Iming the inside of the eyeball. Retinitis. Inflammation of the retina. RMnoscopy. Examination of the nose with the aid of a speculum and light. Rickets. A disease in which the bones become softened and de- formed ; rachitis. Ringworm. A skin disease occur- ring in circular patches. Rods. Rod-shaped bodies of the retina. Saliva. The fluid secreted in the mouth, an important digestive sub- stance. Salivary glands. Those glands which secrete the saliva. Sarcolemma. Elastic sheath that encloses each fiber of striated mus- cle. Scapula. Shoulder-blade. Sclera. The membrane which, with the cornea, forms the external coat of the eyeball. Scoliosis. Lateral curvature of the spine. Scorbutus. A disease due to im- proper food ; scurvy. Scotoma. A blind or partly blind area in the field of vision. Sebaceous glands. The glands which secrete the oil which lubricates the skin. Semilunar area. The crescentic white area near the root of the nail. Septum. A dividing wall or parti- tion, as the nasal septum. Sesamoid bone. A small flat bone occurring in a tendon playing over a bony surface. Sigmoid flexure. That part of the large intestine between the cecum and the rectum, shaped like the let- ter S. Singers' nodes. Enlargement of the edges of the vocal cords. Sinus. A recess, cavity, or hollow space. Skeletal muscle. A muscle at- tached to or moving some part of the skeleton. Soft palate. Back part of the roof of the mouth. Speculum. An instrument for openmg to view a passage or cavity. Sphenoid bone. The small wedge- shaped bone at the base of the skull. Sputum. Matter spit from the mouth. Stapes. Stirrup-shaped bone of the middle ear. Sternum. The breast-bone, to which the ribs are attached in front. Stertorous. Of the nature of snoring. Stimulant. A remedy that excites functional activity in a part. Stool. A fecal discharge. Strabismus. Cross-eye ; squint. Sublingual gland. One of the glands which secrete saliva. Submaxillary gland. One of the glands which secrete saliva. Suspensory ligament. The liga- ment that supports the crystalline lens of the eyeball. GLOSSARY. 535 Syncope. A fainting condition. Synechia. An adliesion, as of tlie iris to the cornea. Syphilis. A contagious venereal disease. Tapetum lucidum. The irides- cent epitheUum of the choroid of cats. Tapotement. A tapping manip- ulation in massage. Tarsal cartilages. Thin cartilages of the eyelids. Temporal bone. Bone at each side and base of the skull containing the hearing apparatus. Tenotomy. The operation of cut- ting a tendon. Terminal plate. The terminal expansion of a motor nerve-branch. Thermotherapy. Treatment of disease by means of heat. Thoracic duct. A duct in which terminate the lymphatics of the lower limbs, abdomen, left arm, left side of the head, neck, and thorax. Thorax. The chest. Thyroid cartilage. The shield- shaped cartilage of the larynx. Tinnitus aurium. A ringing in the ears. Tonsils. Two almond-shaped bodies, one on each side, at the open- ing of the pharynx. These are the faucial tonsils. There is also a third \OT\s\\, pharyng-eal, which see. Tourniquet. Instrument for the compression of blood-vessels to pre- vent access of blood to a limb. Toxic. Pertaining to poisoning. Trachea. The windpipe. Trachoma. A contagious form of conjunctivitis ; " granular lids." True skin. The skin beneath the outer skin ; the derma. Turbinated bodies. Three small bones {turbinated bones) of the nose and their vascular coverings. T3anpanum. The middle ear or ear-drum. u Urea. A white crystalline sub- stance from urine. Uremia. Accumulation of poi- sonous matters in the blood, due to faulty elimination of diseased kid- neys. It may cause convulsions or coma. Uric-acid diathesis. A predis- position to the formation of an excess of uric acid. Urticaria. Hives; nettle-rash. Valve. A fold in a canal which prevents reflux of its contents, as the valves of the heart. Valvulas conniventes. Trans- verse folds in the mucous membrane of the small intestine. Varicose veins. Greatly enlarged and contorted veins. Vascular. Pertaining to, or full of, vessels. Vasomotion. The contraction or dilation of a blood-vessel. Vermiform appendix. A blind pouch in the upper portion of the large intestine. Vibrissse. The hairs within the nostrils. Villi. Small projections from the lining membrane of the intes- tine. 536 GLOSSARY. Visual angle. Angle made at the eye by lines joining the extremities of objects and the nodal point. Vitiligo. A skin disease charac- terized by white patches. Vitreous humor. Transparent semifluid mass in the eyeball be- tween the crystalline lens and the retina. Voluntary muscle. Any muscle controlled by the will. Vomer. Bone which forms the lower and back part of the partition of the nose. INDEX Abdomen, large, 364 Abdominal band for baby, 482 muscles, 340 pains, posture and, 358 Accidents and emergencies, 505 Accommodation, 209 failure, 211 tests, 226 Acetylene, 252 Acid, benzoic, test for detecting, 459 boric, test for detecting, 458 oxalic, poisoning, 522 poisoning by, 522-525 prussic, poisoning, 524 salicylic, test for detecting, 459 steam-bath, 510 sulphuric, poisoning, 522 sulphurous, in canned vege- tables, test for, 446 Acids, poisoning by, 522 Adenoid growths, 105 Adulterants, common, tests for, 461 Adulteration of food, 431, 433 Adulterations, tests of, 457 Advancement of eye-muscles, 219 Air, liquid, 385 of dwellings, change in, 376 purity, 128, 378 Air-cells, function, 122 Alcohol, effect on muscular vigor, 328 on nervous system, 293 restorative properties, 328 Alcoholic beverages, 41 effect on vision, 257 Alcoholism, acute, 524 Alkalis, poisoning by, 522, 525 Almond oil, adulteration, 448 Alum powders, disadvantages, 446 Amber lenses for sports, 271 Amethyst- tinted lenses for sports, 271 Ametropia, 206 "Angel-wing" child, 362 Animal oils, adulteration, 438 Anisometropia, 211 Anti-D trap, 389 Antidotes for poisoning, 521-526 Antrum of Highmore, disease, 104 Anus, 17 Appendix vermiformis, 16 Appetite, 26 Apple stock as adulterant, 454 Apples, adulteration, 452 Aqueous humor, 195 Arc light, 250 Arcus senilis, 186 Argand burner, 250 537 538 INDEX, Artificial coloring, tests for, 460 eyes, 275 feeding of baby, 489 respiration, 516 manual methods of, 518 mechanical devices for, 519 Ashes, disposal, 395 Asphyxiation from gas, 518 from smoke, 518 Astigmatism, 207 Athletic sports, 336 Atropin, 221 Auerbach's plexus, 14 Auricle, 140 Automatic movements, 321 "Babies' sore eyes," 230 Baby, abdominal band for, 482 artificial feeding, 489 basket for, 475 bathing of, 475, 476 bath-tub for, 476, 477 best bed for, 471 care of, in summer, 492 sick, 492 clothing for, 481 diapers, 482 diet after weaning, 491 dressing of, 485 exercise for, 479 food for, 487 layette for, 486 night-clothes for, 484 night-feedings of, 473 outings for, 480 pacifiers, 490 perambulator for, 481 proper resting posture, 474 regular nursing of, 487 sleep required by, 4-^3 soap for bathing, 1.7 8 Baby, socks for, 483 time for short clothes, 486 toilet articles for, 474 training of bladder and bowel muscles, 481 weaning of, 488 Bacilli in air, 129 Backache, 363 Bacteria in water, 386 "Bad breath," 107 Baking-powders, cream of tartar, disadvantages, 446 disadvantages, 445 Baldness, 82 Bandage, four-tailed, 509 handkerchief, 509 many- tailed, 510 Basket, baby's, 475 Bath, baby's, temperature of, 476 Bathing, 60 of baby, 475, 476 Bath-pruritus, 69 Bath-rooms, 393, 394 Bath-tub for baby, 475, 476 Baths, acid steam-, 500 classification, 61 cold, 61 foot, 498 hot, 64, 497 hot-air, 499 Russian, 69, 497 sheet-, 500 Turkish, 68, 497 vapor, 497, 498 varieties. 497 ■«varm, 63 Baudouin's test for sesame oil, 449 Beans, canned, adulteration, 447 Beard, care, 91 Bechi test for cottonseed oil, 438 INDEX. 539 Bed, best, for baby, 471 Bedbugs, 411 Bed-clothing, 81 fasteners, 474 Bed-rooms, ventilation, 380 Beef -extract, adulteration, 438 Beef-juice, adulteration, 439 Beef-tea, adulteration, 439 Belladonna, 221, 523 Bending exercises, 346 of knee from incorrect posture, 355 Benzoic acid, test for detecting, 459 Bicycling, 308 Bifocal lenses, 267 fused, 268 Bile, 15 Biliousness, 50 Binocular vision, advantages, 171 Bites, 507 "Black eye," 174 Bladder muscles of baby, train- ing, 481 "Blear eye," 177 Bleeding, control of, 505 Blepharitis, 177 Blindness, tests, 229 "Blind-spot," 195 Blowers. 380 Boating, 309 Body, imperfect use of, 351 mind, and spirit, interdepend- ence, 365 Body-posture, 351. See also Pos- ture. Boilermaker's deafness, 165 Boric acid, test for detecting, 458 Bowel muscles of baby, training, 481 Brain, compression, 519 Brain, concussion, 519 hygiene, 277 Brandied fruits, adulteration, 454 Bread, 36 Breakfast, 35 Breath, foul, 107 Breathing exercises, 344 physiology, 121 Bronchial tubes, anatomy, 121 Bruises, 508 Brunner's glands, 14 Brushing the hair, 83 Buckwheat flour, adulteration, 444 Building site, 368 Burns, 510 Butter, adulteration, 442 cacao, adulteration, 449 coloring of, 442 test for, 466 Cacao butter, adulteration, 449 Caffein, restorative properties, 327 Cakes, adulteration of, 445 Candling eggs, 464 Candy, adulteration, 451 Canned beans, adulteration, 447 cherries, adulteration, 452 com, adulteration, 446 fruit, adulteration, 452 goods, examination, 464 meat, preservation, 436 mushrooms, adulteration, 455 peas, adulteration, 447 pineapples, adulteration, 452 tomatoes, adulteration, 447 vegetables, adulteration, 446 Canoeing, 309 Caramel as adulterant, test for, 460 540 INDEX, Carbon dioxid, estimation, 376 monoxid poisoning, oxygen for, 519 Carpets, 375 Carriage, influence on digestion, 45 Casein, preparation, 443 Casumen, 443 Cataract, 197 causes, 198 treatment, 198 Cayenne pepper, adulteration, 450 Cecum, 16 Ceilings, height, 370 Cellar, 371 Cereal foods, adulteration, 444 Certified milk, 440 Cerumen, 142 impacted, 144 Cess-pool, 391 Changes in air of dwellings, 376 Cheese, adulteration of, 443 coloring, 443 Chemical and mechanical cooling apparatus, 372 causes of disease, 410 preservatives, 406 tests for detecting, 458 Cherries, canned, adulteration, 452 Maraschino, adulteration, 452 Chest, anatomy, 119 diameter in standing, 357 Chicken, preserved, 435 Childhood, drooping shoulders in, 360 exercise during, 335 nervous and mental hygiene, 281 Children, leg-pains of, 363 Children, round-shoulders' in, 360 stocking-straps for, 360 underwaist for, 360 Cholesteatoma of ear, 154 Choroid, 192 Chyme, 15 Cilia, 176 Ciliary body, 191 muscle, 210 Circulation of spinal cord, pos- ture and, 358 trunk muscles and, 365 Cleaning clothes, 401 house, 398 Climate in consumption, 134 Climatology, 136 Closets, water-, 393 Clothes, disinfection, 401 on fire, 5 1 1 Clothing, 72 absorption of moisture by, 73 color, 75 for baby, 481 for cold weather, 73 for warm weather, 75 heat-conducting poWer, 73 rubber, 76 Cloves, adulteration, 450 "Coating of the tongue," 107 Cockroaches, 411 Cocoa, 37 Coffee, 37 defective, examination of, 463 effect on the nervous system, 294 water test for, 463 Cold bath, 61 creams, 71 douche, 501 pack, 501 "Cold in the head," loi, 429 INDEX. 541 Color-blindness, 227 causes, 227 tests, 228 Coloring, artificial, test for, 460 materials in food, 457 Combs, 83 Complexion, care, 70 Compression of brain, 519 Concussion of brain, 519 Condiments, 38 adulteration, 449 Confectionery, adulteration, 451 Conflagrations, household, 512 Conjunctiva, 180 Conjunctivitis, 180 chronic, 181 Constipation, 48 posture and, 358 Consumption, 129 climatic treatment, 134 prevention, 129 Contusions, 508 Convulsions in children, 520 epileptic, 520 Cooking, 36, 405 Cooling air, 384 apparatus, mechanical and chemical, 372 Copper as adulterant, test for, 460 in canned vegetables, test for, 447 Corn, canned, adulteration, 446 Cornea, 1S5 opacity, 185 Corsets, 80 influence on digestion, 45 Cottonseed oil, Bechi test for, 438 Halphen test for, 438 silver nitrate test for, 438 Cream of tartar baking powder, disadvantages, 446 "Cross-eye," 218 Crystalline lens, 196 Cubic space in dwellings, 370 Curarization, spontaneous, 303 Curd test for purity of milk, 441 Curtains, 372 "Curve of health," 295 Cuts, 505 Cycloplegics, 221 Dairies, inspection, 440 Dandruff, 82 Deafness, boilermaker's, 165 causes, 157 tests, 164 "Degenerates," 278 Dental floss, 25 tape, 25 Derma, 54 Desks in school-rooms, 238 Diapers, 482 Diarrhea, 48 Diet, mixed, 403 regulation, 33 vegetarian, 405 Dietetics, 402 Digestion, influence of dress, 45 intestinal, 15 physiology, 9 stomachal, 13 Digestive apparatus, hygiene, 9 system, effect of exercise on, 331 Dinner, 35 Diphtheria, precautions against, 422 Diplopia, 218 Direct heating, 381 Disease, causes, 410 542 INDEX. Disease, prevention of infectious, 413 transmission, 410 Disinfectants, domestic, 399 Disinfection in infantile paralysis, 427 in infectious diseases, 413 of clothes, 401 Dislocations, 509 Diversion, necessity, 300 Dizziness, 168, 169 and equilibrium, 168 Dog-bites, 507 Domestic hygiene, 367 Doors, 373 Double vision, 218 Douche, cold, 501 Drafts in nursery, dangerous, 470 Drains, 389 Draperies, 372 Dress, influence on digestion, 45 Dressing baby, 485 cord-stump, 485 Drinking water, 40 Drinks, medicated, 468 Drip-sheet, 500 Drooping shoulders in adults, 362 in children, 360 "Drops," dangers, 221 reasons for use, 221 Drowning, 515 Drugs, habit-forming, 467 Drum-membrane of ear, 149 Drunkenness, 524 Dryness of air, 383 Dumb-bell exercises, 343 Duodenum, 13 Dust, city, 396 from stoves, heaters, etc., 383 Dwellings, changes in air of, 376 construction and furnishing, 368 j Ear, external, 139 foreign bodies, 145 hygiene, 139 internal, 162 middle, 155 Earache, 158 Ear-drum, 149 artificial, 151 disease, 153 injuries, 152 Earrings, 140 Ear- trumpets, 169 Ear-wax, 142 impacted, 144 Eating after exercise, 44 Egg-powders, 436 Eggs, 435 candling, 464 examination, 464 salt solution test for, 464 storage, detection, 464 substitutes for, 436 Electric fans, 384 sweepers, 399 telephone-like instruments, 170 Electricity, 250 injuries, 515 Elevation for dwellings, 368 Embroidering, 257 Emergencies, 505 Emmetropia, 206 Engraving, 257 Environment, influence, 278 in cause of disease, 414 Epidermis, 52 Epiglottis, no Epilation, 90 Epileptic convulsions, 520 Epinephrin in resuscitation, 516 Epiphora, 179 Epistaxis, 521 INDEX. 543 Equilibrium and dizziness, i68 Erect posture, 351 maintenance, 353 Ergograph, 328 Eustachian tube, 156 Exercise, amount necessary, 337 during adult life, 335 childhood, 334 youth, 335 eating after, 44 effect, 325 on blood-vessels, 328 on digestive system, 331 on heart, 329 on respiration, 330 on skin, 331 environment and clothing, 339 excessive, 338 for baby, 479 in disease, 339 kind most advantageous, 333 necessity of regulated, 306 physical, 317 waste-products, 328 Exercises, gymnastic, 340 Exposiu-e, southern, 368 Eye, hygiene, 171 Eyeball, anatomy, 171 wounds, 212 Eyebrows, 173 Eye-cups, 184 "Eye-drops," 221 Eye-glaeses, 267 Oxford, 267 Eyelashes, 176 Eyelids, 174 Eye-lotions, 184 Eye-muscles, 217 Eyes, foreign bodies in, 200 injuries, 200 overwork, 245 Eyes, relation to general health, 258 Eyestrain, effect on nutrition, 29 local symptoms, 213 mechanism, 212 in myopia, 216 reflex symptoms, 214 styes from, 213 Face-lotions, 71 Face-powders, 72 Fans, electric, 384 Far-sightedness, 206 Fat, 38 consumption, in exercise, 324 restorative properties, 327 Fatigue of muscle, 325 posture of, 362 Fats, vegetable, adulteration, 449 Filters, domestic, 387 municipal, 386 Filtration of water, 387 Fires, house, 512 First aid, 505 Fish foods, 433 smoked, 434 Fish-hook wounds, 506 Flat foot, standing and, 355 Flavoring extracts, examination, 465 Fleas, 411, 412 Flies, 373, 411, 412 Floor-coverings, 374 Floor-exercise, 348 Floors, 374 Flour, adulteration, test for, 466 buckwheat, adulteration, 444 rye, adulteration, 444 wheat, adulteration, 444 Fly poisons, 412 Food, 402 ' 544 INDEX. Food adulteration, 405, 431, 433 analysis, 404 care of, 43 1 cereal, adulteration of, 444 coloring materials in, 457 cost, 403 definition of, 431 deterioration, 431 eggs, 435 examination, 463 fish, 433 for baby, 487 infection from, 406 inspection, 407 nutritive value, 403 poultry, 434 preservatives in, 406, 457 reagents in, 457 Food-substances, transformation into energy, 323 Foot-baths, 498 Formaldehyd disinfection, 401 Foul air in nursery, removal, 470 Foundations, building, 368 Four-tailed bandage, 509 Fractures, 509 Freeman's pasteurizer, 489 Freezing, 514 Frost-bite, 514 Fruit, 37 adulteration, 452 brandied, adulteration, 454 syrups, adulteration, 453 Fumes, noxious, 396 Furnace-fire, 383 Furnace-heating, 381 Fused bifocal lenses, 268 Gall-bi^adder, 15 Garbage, 394 Garters, 79 Gas, sewer-, 392 Gas-asph3rxiation, 518 Gastric juice, 1 1 Gelatin, adulteration, 439 in ice cream, test for, 467 Ginger, adulteration, 450 Glaucoma, 199 Glossary, 527-536 Glucose consumption in exercise, 324 test for detecting, 461 Gluten, test for, 444 Glycogen consumption in exer- cise, 324 Golf, advantages, 307 Granular lids, 181 Gray hair, 90 Grip, 429 precautions against, 429 Ground spices, adulteration, 450 Growing pains, 363 Gymnastics, 336, 340 Habit-forming drugs, 467 Hair, anatomy, 58 care, 82 dyeing, 91 removal, 90 singeing, 89 superfluous, 90 wetting, 90 Hair-brushes, 83 Hair-cutting, 88 Hair-dressing, 89 Hair-dyes, 91 Hair-pomades, 89 "Hair-restorers," 89 Hallways, 372 Halphen test for cottonseed oil, 438 Handkerchief bandages, 509 INDEX. 545 Hats, 86 Head, cold in, 429 Head-accidents, 519 Headache mixtures, 467 poisoning from, 468 Head-gear, 86 Hearing, physiology, 155 tests, 164 Heart, effect of exercise on 329 posture and, 358 Heat-exhaustion, 514 Heating, 381 and ventilation combined, 381 direct, 381 excessive, 383 indirect, 381 Height of dwellings, 370 Hematemesis, 520 Hemoptysis, 520 Hemorrhage, control, 505 of lungs, 520 Heredity, influence, 278, 414 Heterophoria, 218 Hips in incorrect posture, 356 Holmgren test, 228 Homatropin, 222 Home-gymnastics, 340 Honey, adulteration, 451 Hook-fronts for spectacles, 269 Hospitalization in poliomyelitis, 428 Hot bath, 67, 497, 498, 499 pack, 501 vapor baths, 498 Hot- water heating, 381, 382 House-cleaning, 398 House-construction, 368 House-drain, 389 House- quarantine, 416 Humidity, 378 Humors of eye, 195 35 Hunting, 309 Hutchinson's teeth, 19 Hygiene of infancy, 470 Hygrometer, 378 Hyperopia, 206 Ice, contamination, 455 cream, gelatin in, test for, 467 infection from, 455, 456 melted, as potable water, 456 Ice-chest, care of, 432 Ileum, 13 Illuminating-gas, 249 asphyxiation from, 518 Illumination, artificial, 247 indirect, 248 Incandescent light, 250 Indigestion, posture and, 358 Indirect heating, 381 illumination, 248 Infancy, hygiene of, 470 Infantile paralysis, 424 causes, 424 control of, 426 diet in, 425 hospitalization in, 428 period of isolation, 417 precautions against, 425 for physicians and nurses in, 428 symptoms, 424 Infants' eyes, care, 230 Infection about roots of teeth as cause of bad health, 23 accompanying pyorrhea, 23 from food, 406 susceptibility to, 415 Infectious diseases, 410 Insalivation, 9 Insects, infection by, 373, 411 Insect-stings, 507 546 INDEX. Insomnia, 313 causes, 313 treatment, 314 Inspection, food, 407 meat, 407 milk, 408 Intestinal digestion, 15 Intestine, displacements, posture and, 358 large, 16 small, 13 Invalidism, body posture and, 351 Invert-sugar, test for detecting, 462 lodin number of vegetable oUs, 448 Iris, 186 Iritis, 191 Isolation in infectious diseases, 413 time, 416 Ivy-poisoning, 508 Jams, adulteration, 453 Jaw, dislocation, 509 Jejunum, 13 Jellies, adulteration, 406, 453 Kalsomined walls, 374 Kerosene, 249 Ketchup, tomato, adulteration, 448 Kidney displacements, posture and, 358 Kindergarten, dangers, 231 Kitchen, 372 Knee bending from incorrect posture, 355 Kyphosis, 125 Lacrimal apparatus, 178 Lard, adulteration, 437 Laryngopharynx, 108 Laryngoscopy, no Larynx, anatomy, 108 examination, no functions, in Laundering, 400 Layette for baby, 486 Leading, 246 Leg-pains, 363 Lemon extract, examination of, quality, 465 Lenses, amber, 271 amethyst-tinted, 271 circular, 264 periscopic, 265 spectacle, 261, 264 Lieberkiihn's glands, 14 Lighting, 236 artificial, 246 Lightning, injuries from, 515 Lime-juice, adulteration, 453 Liquid air, 385 Liver, 15 displacements, posture and, 358 Louse, body, typhus fever spread by, 411 Luncheon, 35 Lungs, anatomy, 121 consumption, 129 expansion, posture and, 357 hemorrhage, 520 tuberculosis, 129 Lying postiu-e, 358 Macaroni, coloring of, 445 Mackintoshes, 76 Macula lutea, 193 Manicuring, 92 Many- tailed bandage, 510 INDEX. 547 Maraschino cherries, adultera- tion, 452 Mariotte's blind spot, 195 Marjoram, adulteration, 450 Marmalades, adulteration, 453 Massage, 503 cardiac, in resuscitation, 516 method, 504 movements, 503 rules, 503 value, 503 Mastication, 9 Meals, regulation, 31 Meat, canned, preservation of, 436 infection, 407 mince, adulteratipn, 451 pickled, preservation, 436 preserved, 436 Meat-powders, 439 Mechanical and chemical cooling apparatus, 372 Medicated drinks, 468 Meibomian glands, 175 Meissner's plexus, 14 Meniere's disease, 169 Menstruation, influence, 282 Microbes in air, 129 Milk, 440 certified, 440 contamination, 440 curd test for purity, 441 infection, 406 inspection, 408 mothers', 487 artificial, 489 increashig supply of, 488 pasteurized, 410, 440 watered, test for, 467 Milk-products, 440 Mince meat, adulteration, 451 Mixed diet, 403 Molasses, adulteration of, 445, 450 Monocles, 270 Mosquitos, 373, 411 bites, 507 Mouth-breathing, 17, 99 Mouth- wash, 26 Movement, muscular, 317 Moving pictures, 258 Muscae volitantes, 196 Muscicides, 412 Muscle-fatigue, 325 Muscles, classification, 317 physiology, 318 Muscular contraction, 318 Mushrooms, canned, adultera- tion, 455 how to distinguish, 454 Mustard, adulterated, 449, 450 Mydriatics, 221 dangers, 222 Myopia, 207 Nails, care, 92 Nasal douche, 160 ♦ duct, 179 passages, 98 polyps, 99 septum, deformities, 98 Nasopharynx, anatomy, 104 Near-sightedness, 207 Needle-wounds, 506 "Nerve-deafness," 163 Nerves, anatomy and physiology, 277 Nervous indigestion, posture and, 358 prostration, 284 posture and, 365 system, hygiene, 277 548 INDEX. Nervous tissue, 277 weakness, posture and, 358 "Nervousness," 284 Neurasthenia, causation, 285 definition, 285 general remarks, 284 pathology, 291 prognosis, 292 symptoms, 287 treatment, 292 "Nevo," 384 Night-clothes for baby, 484 Night-feeding of baby, 473 Night-lamp for nursery, 472 Nipples, artificial, 488 Noises, city, 396 "Noises in the ear," 165 Nose, anatomy, 94 care, 100 mucous membrane, 97 picking, 104 polyps, 99 septum of, deformities, 98 Nosebleed, 521 Nuisances, 395 Nursery, care of, 470 danger of draughts in, 470 furnishings of, 471 night-lamp for, 472 removal of foul air, 470 temperature of, 471 Nurses, precautions for, in polio- myelitis, 428 Nursing of baby, regular, 487 Nutmeg seed, adulteration, 449 Nutrition, disturbances, 28 OatmhaIv, adulteration, 444 Occupation, posture and, 360, 362 Ocular muscles, 217 Odors, foul, 395 Oil, 38 almond, adulteration, 448 animal, adulteration, 438 cottonseed, Bechi test for, 438 Halphen test for, 438 silver nitrate test for, 438 of vitriol, poisoning, 522 olive, adulteration, 448 palm, adulteration, 449 peanut, test for, 449 sesame, test for, 449 vegetable, adulteration, 448 iodin number, 448 Oils, 38 Old-age sight, 211 Oleomargarin, 440, 442 Olive oil, adulteration, 448 Ophthalmia neonatorum, 230 Ophthalmoscopy, 189 Opium-poisoning, 523 Optic nerve, 194 Optician, province, 259 Organic diseases caused by in- fected roots of teeth, 23 matter in air, 377 Oropharynx, anatomy, 106 Outings for baby, 480 Overwork, 295 mental, 296 physical, 302 Oxalic acid poisoning, 522 Oxford eyeglasses, 267 Oxygen for carbon monoxid poisoning, 519 in resuscitation, 516 Oysters, 434 infection from, 407 Pacifiers, baby, 490 Pack, cold, 501 hot, 501 INDEX, 549 Pack, partial, 502 Painted walls, 374 Palm oil, adulteration, 449 Pancreas, 15 Pantoscopic spectacles, 269 Paper for books, 245 Paralysis, infantile, 424 causes, 424 control of, 426 diet in, 425 hospitalization in, 428 period of isolation, 417 precautions against, 425 for physicians] and nurses in, 428 symptoms, 424 . Pasteurization, 489 Pasteurized milk, 410, 440 Pasteurizer, Freeman's, 489 Peanut oil, test for, 449 Peas, canned, adulteration, 447 Pepper, Cayenne, adulteration, 450 Perambulator for baby, 481 Periscopic lenses, 265 Perspiratory glands, 54 Peyer's glands, 15 Pharyngeal tonsil, 98 Photophobia, 271 Phthisis, 129 climatic treatment, 134 prevention, 129 Physical exercise, 317 training, 331 and mental training, 331 Physicians, precautions for, in poliomyelitis, 428 Pickled meats, preservation, 436 Pictures, moving, 258 Pie-fillers, adulteration, 451 "Pince-nex," 267 Pineapple, canned, adulteration, 452 Pinguecula, 184 Plague spread by rat-flea, 411 Pleura, 123 Plumbing, 389 Pneumonia, precautions against, 429 Poison, table, 525 Poisoning, 521 antidotes for, 521-526 from headache mixtures, 467 Poliomyelitis, anterior, 424 causes, 424 control of, 426 diet in, 425 hospitalization in, 428 period of isolation, 417 precautions against, 425 for physicians and nurses in, 428 symptoms, 424 Polyps, nasal, 99 Pomades, 89 Posture, 351 backache and, 363 erect, 351 maintenance, 353 lying, 358 mechanical supports, 362 nervous prostration and, 365 occupation and, 360, 362 of fatigue, 362 proper resting, for baby, 473 rising, 358 sitting, 358, 364 slouching, 359 slumping, 359 stooping, 358 viscera and, 353 walking, 358 550 INDEX, Poultry, 434 Prejudice against spectacles, 272 Presbyopia, 211 Preservation of food, 406 by chemicals, 406 by refrigeration, 406 Preservatives, chemical, test for detecting, 458 in food, 406, 457 Preserved chicken, 435 meats, 436 turkey, 435 Preserves, adulteration, 453 Printing, 243 Prismatic devices for lighting, 252 Proprietary remedies, 469 Prussic acid poisoning, 524 Pterygium, 184 Ptyalin, 9 Puberty and its attendant dan- gers, 282 Pulmotor, 519 Pulse, 495 Punctured wounds, 506 Pupil, 188 Pure water, definition, 388 Purification of water, 386 Purifying agents, 399 Pyorrhea alveolaris, 23 infection accompanying, 23 Quarantine, house-, 416 Rat-flea, infection from, 413 plague spread by, 411 Rat-poison, 524 Rats, 413 Reading hygienic precautions in, 254 Reagents in food, 457 Recreation, mental, 300 Rectum, 17 Reflex movements, 322 Refrigerator, 372 Relaxing exercises, 349 Rennet, preserving, 443 Respiration, 497 effect of exercise, 330 physiology, 121 Respiratory gymnastics, 127 Rest, need, 300 Resuscitation, 516 cardiac massage in, 516 method of, 516 oxygen in, 5 1 6 saline solution in, 516 simple apparatus in, 516 Retina, 192 Rice, adulteration, 444 Rising posture, 358 Roof, house-, 370 Rooms, size, 370 Rose- test, 229 Round-shoulders, 356 in adults, 362 in children, 360 Rugs, 375 Russian bath, 69, 497 Rye flour, adulteration, 444 Saccharin, test for detecting, 459 Sacro- iliac joints, 362 Salicylic acid, test for detecting, 459 Saline solution in resuscitation, 516 Salivary glands, 9 Salt solution test for eggs, 464 Salts, 40 Samose, 443 INDEX. 551 Sanatogen, 443 Scalds, 510 Scalp, care, 82 massage, 87 Scarlet fever, precautions against, 423 School, time of entrance, 232 School-books, 243 School-buildings, 236 School-children, ametropia in, 234 eyes, care at home, 233 medical examination, 243 School-hygiene, 235 School-life, dangers, 233 School-rooms, 237 Sclera, 186 Scoliosis, 125 Scotom.as, 193 Sea-bathing, 66 Seats in school-rooms, 238 Sebaceous glands, 57 "Second-sight," 199 "Second-wind," 100 Septum, nasal, 98 Sesame oil, test for, 449 Sewage, surface irrigation method for disposal of, 392 Sewer-gas, 392 Sewers, 389 Sewing, 257 Sexual instinct, influence, 283 Shampooing, 84 Shaving, 92 Sheet-bath, 500 Shoes, 76 "Shoulder-braces," 127 Shower-bath, 63 Shrug-movements, 346 Sick-room, hygiene, 415 Sigmoid flexure, 17 Silver nitrate test for cottonseed oil, 438 Singeing hair, 89 Singing, 113 improper methods, 115 Sinks, 372 Site, building, 368 Sitting, bad habits in, 364 posture, 358 Skin, anatomy, 52 and its appendages, hygiene, 52 effect of exercise on, 331 Slates, 242 Sleep, 310 physiologic considerations, 310 required by baby, 473 Sleeplessness, 313 Slouching posture, 359 Slumping posture, 359 Small-pox, precautions against, 420 Smoke-asphyxia, 518 Smoke-nuisance, 395 Smoked fish, 434 Smoking, effect on vision, 257 Snake-bites, 507 Soap, 65, 70 for bathing baby, 478 medicated, 66 Socks, 79 for baby, 483 Soil for building site, 368 Solution, saline, in resuscitation, 516 Soothing syrups, 468 Soot-nuisance, 397 Spectacles, 259 advantages, 261 bifocal, 267 care, 265 construction, 262 552 INDEX. Spectacles, fitting, 262 initial discomfort, 273 invention, 259 necessity of changing, 275 pantoscopic, 269 position, 265 prejudice against, 271 tinted, 270 trifocal, 269 Spices, ground, adulteration, 450 Spinal cord, circulation, posture and, 358 trunk muscles and, 365 Spine, curvature, 125 Splinters, 507 Sponge-bath, 62 Spontaneous movement, 317 Sports, amber-tinted lenses for, 271 amethyst- tinted lenses for, 271 and gymnastics, 336 "Spots before the eyes," 196 Spotted fever, 424 Sprains, 508 Squint, 218 Stairways, 371, 372 Standing with hands in pockets, 363 Starch in condiments, test for detecting, 463 in jellies, test for detecting, 462 Starches, adulteration, 445 Steam inhalation, 512 Steam-bath, acid, 500 Steam-heating, 381, 382 Steps, 372 Stimulants, 42 Stmgs, 507 Stocking-straps, 360 Stockings, 79 Stomach, absorption from, 13 anatomy, 11 displacements, posture and, 358 hemorrhage, 520 Stomach-pumps, 522 Stooping posttue, 358 Stoop-shoulders, 356 in adults, 362 in children, 360 Storage eggs, detection, 464 Stoves, 381 Strabismus, 218 Stretching exercises, 343 Strychnin-poisoning, 524 Study, regulation, 242 Styes, relief of, 213 Sugar, 38 adulteration, 450 invert-, test for detecting, 462 restorative properties, 327 Sulphuric acid poisoning, 522 Sulphurous acid in canned vege- tables, test for, 446 Summer, care of baby in, 492 Sunstroke, 514 Superfluous hairs, 90 Susceptibility to infection, 414 "Swedish movements," 337 Sweeping, 399 Syrups, fruit, adulteration, 453 mixed, adulteration, 450 soothing, 468 Tank, flushing, 392, 393 Tea, 37 effect on nervous system, 294 Tear-apparatus, 178 "Tearing," 179 Tears, overflow, 179 Teeth, decay, 20 deformities, 17 INDEX, 553 Teeth, devitalized, 23 infection of roots of, as source of organic disease, 23 preservation, 24 Temperatrue of baby's bath, 476 of nursery, 471 regulation, 55 taking, 496 Tennis, 308 Tenon's capsule, 172 Tenotomy of eye-muscle, 219 Test, Baudouin's, for sesame oil, 449 Bechi, for cottonseed oil 438 for adulterated vinegar, 466 for adulteration of flour, 466 for artificial coloring, 460 for butter, 466 for caramel as adulterant, 460 for common adulterants, 461 for copper as adulterant, 460 in canned vegetables, 447 for detecting benzoic acid, 459 boric acid, 458 chemical preservatives, 458 glucose, 461 invert-sugar, 462 saccharin, 459 salicylic acid, 459 for gelatin in ice cream, 467 for gluten, 444 for starch as adulterant, 462, 463 for sulphurous acid in canned vegetables, 446 for tumeric as adulterant, 460 for watered milk, 467 Halphen, for cottonseed oil, 438 of adulterations, 457 salt solution, for eggs, 464 Test, silver nitrate, for cotton- seed oil, 438 water, for coffee, 463 Test-types, 223 Thermometer, clinical, 497 Thomson-stick, 228 Thorax, 119 deformities, 125 muscles, 120 phthisical, 127 "Thumb-sucking," 18 Tinnitus aurium, 163 Tinted glasses, 270 Tobacco, effect on nervous sys- tem, 294 on vision, 257 Toilet articles for baby, 474 Toilet-creams, 71 Toilet-lotions, 71 Toilet-room, 393 Tomato ketchup, adulteration, 448 Tomatoes, canned, adulteration, 447 Tongue, "coating," 107 Tonsils, disease, 107 deleterious effect of, on gen- eral health, 107 Tooth-brushes, 24 Tooth-powder, 25 Toric lenses, 265 large, 271 Tourniquet, 505, 506 Trachoma, 182 Training baby's bladder and bowel muscles, 481 physical, 331 Traps in plumbing, 390 Trifocal spectacles, 269 Truffles, adulteration, 455 Tubercle bacillus, 129 554 INDEX. Tuberculosis, climatic treatment, 134 prevention, 129 Turbinated bodies, 96 Turkey, preserved, 435 Turkish bath, 67, 497 Turmeric, test for, 460 Twisting exercises, 345 Tympanic cavity, 155, 158 membrane, 149 Type, 243 Typhoid fever, precautions against, 419 vaccination against, 420 Typhus fever spread by body louse, 411 Underwaist for children, 360 Vaccination against typhoid fever, 420 Vacuum cleaners, 399 Vanilla extract, substitutes for, 465 Vanillin, artificial, 465 Vapor bath, 69, 497, 498 Varicose veins, 80 Vegetable fats, adulteration, 449 oils, adulteration, 448 iodin number, 448 Vegetables, canned, adulteration, 446 infection from 407 Vegetarian diet, 405 Veils, effect on vision, 257 Ventilation, 375 and heating, combined system, 381 artificial, 380 natural, 379 of bed-rooms, 380 Vermiform appendix, 16 Vermin, infection by, 411 Vinegar, adulteration, test for, 466 Viscera, posture and, 353 Vision, testing acuity, 223 Visual tests, 223 Vitreous humor, 196 Vitriol, oil of, poisoning, 522 Vocal and respiratory apparatus, hygiene, 94 cords, J 09 Voice, care, 113 cultivation, 115 excessive use, 117 "throaty," 116 Voice-deterioration, causes, 114 Voice-sounds, production, 112 Walking posture, 358 Wall-covering, 373 Wall-papers, 373 Walls, 373 building, 369 Washing, 400 soda, 399 Waste-paper, 395 Waste-substances, production of, during exercise, 328 Water, 40 pure, definition, 388 purification, 386 test for coffee, 463 Water-closets, 392, 393 Water purification, 386 Water-supply, 385 Water-waste preventers, 393 Watered milk, test for, 467 Weaning, 488 diet after, 491 "What to do in case of fire," 512 INDEX. 555 Wheat flour, adulteration, 444 White-washing, 374 "Wild hairs," 177 "Windmill movements," 347 Window- ventilation, 379 Windows, 373 Windows of school-room, 236 Wisconsin curd test for purity of milk, 441 Worry, 299 Wounds, 505 Writing, 245