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 ADDING YEARS 
 TO YOUR LIFE
 
 BOOKS BY HENRY SMITH WILLIAMS 
 
 THE STORY OF NINETEENTH CENTURY 
 SCIENCE. Harper & Bros., 1900. 
 " He must have a dull mind indeed who can read 
 this book without fascination." Christian Register. 
 THE HISTORY OF THE ART OF WRITING. 
 (Four massive portfolios with 200 facsimiles 
 in tone and color.) 
 
 "One of the most superb examples of book- 
 making in America since Audubon's masterpiece." 
 
 Rupert Hughes in the Marconigram. 
 
 THE HISTORIANS' HISTORY OF THE 
 WORLD: A Comprehensive Narrative of the 
 Rise and development of Nations. (25 vols. 
 with about 3,000 illustrations.) Edited with 
 the collaboration of many specialists, European 
 and American. 
 
 "A work of epoch-making importance compar- 
 able in scholarship and authority to La Grande 
 Encyclopedic, the Dictionary of National Biog- 
 raphy, the New English Dictionary, and the En- 
 cyclopcedia Britannica." The Times, London. 
 A HISTORY OF SCIENCE. (5 vols., fully illus- 
 trated.) Harper & Bros., 1904. 
 "At once a source of information and an in- 
 spiration." Prof. Louis G. Nolte. 
 ALCOHOL: How it Affects the Individual, the 
 Community, and the Race. The Century Co., 1909. 
 " By your clear and dispassionate presentation 
 of this subject you have earned the respect and 
 gratitude of a generation, and have done the good 
 of an average life time." Letter to the Author. 
 EVERY-DAY SCIENCE: The Story of Man's 
 Application of Organized Knowledge to the 
 Needs of Practical Life. (11 vols., fully illus- 
 trated.) The Goodhue Co., 1909. 
 THE WONDERS OF SCIENCE IN MODERN 
 LIFE. (10 vols., fully illustrated.) Funk & 
 Wagnalls Co., 1912. 
 
 MIRACLES OF SCIENCE. Harper & Bros., 1913. 
 
 THE SCIENCE OF HAPPINESS. Harper & 
 
 Bros., 1909. New edition, The Goodhue Co., 1913. 
 
 THE WORK AND METHODS OF LUTHER 
 
 BURBANK. (12 vols., with 1,260 illustrations 
 
 m color.) Edited for The Luther Burbank 
 
 Society, of whose publications Dr. Williams is 
 
 Editor-in-Chief. In press.
 
 A series of simple but highly effective gymnastics aimed at 
 all-around development of the abdominal muscles
 
 Adding Years 
 To Your Life 
 
 By 
 
 Henry Smith Williams, M.D., LL.D. 
 
 Author of " A History of Science," " The 
 
 Science of Happiness," " The Effect of 
 
 Alcohol," etc. 
 
 Illustrated 
 
 Hearst's International Library Co. 
 New York MCMXIV
 
 Copyright, 1912, 1913, by 
 INTERNATIONAL MAGAZINE Co. 
 
 Copyright, 1914, by 
 HEARST'S INTERNATIONAL LIBRARY Co., INC. 
 
 All rights reserved, including that of translation 
 into foreign languages, including the Scandinavian
 
 CONTENTS 
 
 CHAPTER PAGE 
 
 I THE DUEL WITH OLD AGE "... 15 
 
 II THE BATTLE OF THE MICROBES . . 40 
 
 III MESSENGERS OF DEATH AND How TO 
 
 OUTWIT THEM 71 
 
 IV Is YOUR BRAIN ALL BIGHT? . . 93 
 V ARE YOUR NERVES IN TUNE ? . . . 117 
 
 VI CAN You SEE STRAIGHT? . . .153 
 
 VII Do You CHOOSE YOUR CHILDREN ? . 181 
 
 VIII GIVE YOUR CHILDREN A CHANCE . . 213 
 
 IX ADDING YEARS TO YOUR LIFE . . 245 
 
 INDEX 277 
 
 2052697
 
 ILLUSTRATIONS 
 
 A series of simple but highly effective gym- 
 nastics aimed at all-around development 
 of the abdominal muscles . . Frontispiece 
 
 FACING PAGE 
 
 The milk supply is everywhere under sur- 
 veillance of health boards nowadays . 66 
 
 Four of the best known scientists . . . 204 
 
 Determining the mental age of a child by the 
 application of the Binet-Simon and 
 Sequin tests 224 
 
 The opportunities for outdoor life for chil- 
 dren have now been extended to school 
 hours in some places . . . 240 
 
 Dr. Bishop using the sphygmograph to ascer- 
 tain the quality of the heartbeats . . 256
 
 ADDING YEARS 
 TO YOUR LIFE
 
 
 The Duel with Old Age 
 
 GROWING old and dying seem futile perform- 
 ances, when you stop to think of the matter. 
 
 Just why a man who has lived in unvarying 
 health and strength for, say, thirty years should 
 not continue to do so for three hundred or three 
 thousand years is not intrinsically obvious. Cer- 
 tain enthusiasts have all along contended that 
 he could do so if only he could find out just how 
 the trick was to be accomplished. 
 
 In the Middle Ages, this idea seemed so self- 
 evident that no one thought of doubting it. So 
 hosts of men of talent gave their lives to the quest 
 of the philosopher's stone. 
 
 Then there were men of another cast of mind 
 who believed that the special elixir of life must 
 be a product of nature herself rather than of the 
 laboratory, and who sought the beneficent foun- 
 tain of eternal youth in far-off regions of the 
 world. Foremost among these adventurers, as 
 every schoolboy will recall, was Ponce de Leon, 
 who sought but failed to find -the beneficent 
 spring in Florida. 
 
 In our day the problem has been attacked from 
 many angles. There are no unexplored lands to 
 search out, and at last we are forced to believe 
 
 15
 
 !6 Adding Years to Your Life 
 
 that nature has nowhere supplied a spring of 
 eternal youth. But there are still workers in the 
 laboratory who believe that the dream of the 
 alchemists was not a hopeless one, and who are 
 attempting to apply the new knowledge of modern 
 science to the old familiar quest. 
 
 Metchnikoff, Seeker After Eternal Youth 
 
 The Ponce de Leon of our day is Professor Elie 
 Metchnikoff, of the Pasteur Institute in Paris. 
 Professor Metchnikoff gained world-wide fame 
 some twenty-five years ago through his researches 
 on the white blood-corpuscles. He proved that 
 these little organisms in the blood have the func- 
 tion of destroying bacteria and thus of helping 
 man to preserve his health. This demonstration 
 prepared the way for much of the later progress 
 of preventive medicine. It also suggested to Pro- 
 fessor Metchnikoff himself problems having to do 
 with the life and death of human tissues that have 
 been the stimulus for all his more recent work. 
 Latterly this work has focused specifically on one 
 subject, the conquest of old age. The savant him- 
 self believes that he has at last partially solved 
 the problem. 
 
 A beginning in this direction was made by Pro- 
 fessor Metchnikoff some years ago when he ob- 
 served that the peasants of Bulgaria appeared 
 to be a very long-lived race. Metchnikoff noted 
 that the peasants in question lived largely on a 
 diet of sour milk. He associated this custom with
 
 The Duel with Old Age 17 
 
 the observed longevity and sought for the con- 
 nection. Milk sours because of the presence of 
 certain microbes called lactic-acid bacilli. Hence 
 sour milk contains a large quantity of these 
 minute organisms. Tracing the history of these 
 bacilli when taken into the stomach, Metchnikoff 
 found that they live and proliferate in the intes- 
 tinal canal, and there tend to neutralize certain 
 poisons that are deleterious to the human system 
 if absorbed. 
 
 Acting on these observations, Metchnikoff in- 
 troduced a sour-milk treatment which has been 
 extensively employed by physicians all over the 
 world. It must be admitted, however, that the 
 results of this treatment have not been convincing 
 to the mass of the profession. 
 
 Glycobacterium Bacillus of Long Life 
 
 Metchnikoff himself has felt that the lactic-acid 
 bacillus was hampered in its beneficial activities 
 by the lack of food suited to its needs to be found 
 normally in the intestinal tract. So he sought a 
 means of remedying this difficulty. Very recently 
 a clue was given by the discovery, made by M. 
 Woolman, a fellow-worker at the Pasteur Insti- 
 tute, of a bacillus which can generate sugar, and 
 which has been given the name ' ' glycobacterium. ' ' 
 
 This newly discovered organism was found in 
 the intestinal tract of the dog, but it may be cul- 
 tivated in the laboratory and made to colonize in 
 the human system.
 
 i8 Adding Years to Your Life 
 
 The advantage of such colonization is, accord- 
 ing to Professor Metchnikoff, that by supplying 
 food for the lactic-acid bacilli, the glycobacteria 
 will be instrumental in enabling those organisms 
 to carry out their useful functions of neutralizing 
 the so-called indols and phenols, the presence of 
 which in the intestinal tract is believed to be 
 so deleterious to the organism. 
 
 It will be obvious that the real utility of the 
 glycobacteria in performing this highly desirable 
 function can be determined experimentally only 
 after many years of trial. But, on the other hand, 
 it cannot be supposed that a scientist of Pro- 
 fessor Metchnikoff 's reputation makes any con- 
 clusions without a good many facts or valid theo- 
 ries to give them support. Let us inquire, then, 
 very briefly, as to the grounds on which Professor 
 Metchnikoff 's belief that he is on the track of the 
 philosopher's stone is based. 
 
 Professor Metchnikoff 's chief efforts, as we 
 have seen, are aimed against certain poisons that 
 are generated in the intestinal tract. 
 
 There is no question that these poisons are actu- 
 ally generated there, and that they are capable of 
 absorption into the system and of producing dele- 
 terious effects. In a crude general way this has 
 been familiar knowledge of medical men from the 
 earliest times ; though it remained for the physio- 
 logical chemist of our time to test and classify and 
 name the poisons. 
 
 It is recorded that the medieval alchemist- 
 physician, Paracelsus, believed that all foods con-
 
 The Duel with Old Age 19 
 
 tain elements of poison, and that it is the function 
 of the gastric juice to act as an alchemist, trans- 
 forming the poisons into wholesome products. 
 With a little latitude of interpretation, the idea 
 is not far wrong. All foods do contain elements 
 that, if not properly compounded, would be poison- 
 ous to the system. The chief universal elements 
 that enter into foodstuffs are carbon, hydrogen, 
 oxygen, and nitrogen. 
 
 Properly compounded, these are not only whole- 
 some, they are absolutely indispensable ; but if you 
 break up the molecules of, let us say, meat or bread 
 into their elements, you may have a variety of 
 poisons. 
 
 Thus carbon unites with oxygen to form the 
 poisonous carbonic acid gas, which if not immedi- 
 ately thrown off by the lungs, suffocates or as- 
 phyxiates the cells in general and causes death. 
 Similarly oxidized, the nitrogen and carbon and 
 hydrogen elements of the food-molecule may form, 
 and constantly do form, in the system urea and 
 uric-acid compounds that, if not immediately elim- 
 inated by way of the kidneys, produce stupor and 
 death with equal certainty. These are familiar 
 facts of elementary physiology. 
 
 But does it not seem probable that elimination 
 of these poisons is sometimes only partially per- 
 formed? Every physician knows that such is the 
 case. A whole coterie of diseases are of such 
 recognized origin. 
 
 May it not be true, then, that a slow poisoning 
 occasioned by partially retained organic com-
 
 20 Adding Years to Your Life 
 
 pounds is the cause of that gradual decay which 
 leads to senility and death? 
 
 To this question Metchnikoff answers unequivo- 
 cally, Yes. He believes that auto-intoxication, 
 through the acumulation in the system of waste 
 products, is very largely responsible for the fact 
 that tissues in the body gradually lose their power 
 of normal reproduction and ultimately functionate 
 so feebly as to cause the individual to become 
 senile and to die. 
 
 Single-celled Organisms Never Die 
 
 The original conception that probably put Pro- 
 fessor Metchnikoff on the track of this idea was 
 the theory of Professor Weismann, according to 
 which single-celled organisms (so-called infuso- 
 rians or protozoans) never die a normal death. 
 The idea is startling, but simple enough when we 
 consider the conditions. If you observe a proto- 
 zoan under the microscope you will see a trans- 
 lucent particle of protoplasm which moves about, 
 seemingly responds to stimuli (as from coming in 
 contact with other objects), absorbs certain par- 
 ticles by way of food, and excretes such portions 
 of the food as are not to its liking. 
 
 The bit of protoplasm will be observed to grow 
 until it attains a fairly definite maximum size. 
 
 Then it will become constricted at the middle, 
 presently dividing into two bits of protoplasm 
 each of which is precisely like the original in 
 quality and activities, but of half size.
 
 The Duel with Old Age 21 
 
 Each of the new protozoa will re-enact the life 
 of the parent of whose divided body they are com- 
 posed. Each will feed and grow and presently 
 divide to constitute two offspring. As the process 
 of growth and so-called reproducton by fission 
 requires only a few hours, there will be succes- 
 sively two, four, eight, sixteen, thirty-two, sixty- 
 four protozoa where at first there was only one. 
 And this process continuing, it is obvious that the 
 progeny of the original protozoan increase in geo- 
 metrical ratio, until in the course of a few weeks 
 they will number as anyone who chooses to make 
 the successive multiplications can prove thou- 
 sands, millions, billions, of individuals. 
 
 If nothing interfered with their growth, there 
 might be tons of them in a few weeks. 
 
 Meantime what has become of the original pro- 
 tozoan! It is rather curious to reflect on the suc- 
 cessive divisions of the fleck of matter that com- 
 posed it. The entire body of the protozoan, it will 
 be recalled, divided to produce two protozoa. 
 These offspring, then, are not merely children of 
 the original protozoan; they together constitute 
 the total bulk and personality of the original 
 organism. 
 
 And so with each successive generation. The 
 parent organism is larger but no older than its 
 two offspring; and, extending the idea all along 
 the line, it would seem that, of the myriads of 
 protozoans, those of the last generation represent 
 merely the divided personality of the first proto- 
 zoan, and are as old as their original ancestor.
 
 33 Adding Years to Your Life 
 
 The thing sounds paradoxical when phrased in 
 just that way, yet it seems to express the fact. 
 
 Stated otherwise, it appears that the protozoan 
 never dies, but, barring accidents, is perpetuated 
 throughout the ages in an unending series of de- 
 scendants that represent not offspring so much 
 as a continuity of its own person. 
 
 This idea of the " potential immortality " of 
 the single-celled organism, as Weismann phrased 
 it, took instant possession of the biological world, 
 and led to renewed questioning as to why the cells 
 should lose this capacity for immortality when 
 they chanced to be built together into the organ- 
 ism of a higher animal. 
 
 The matter seemed so important, that it was 
 presently put to tests, to establish whether the 
 protozoan really is immortal as Weismann 
 thought. Some of these experiments were discon- 
 certing. Professor Maupas studied a particular 
 type of protozoan, carefully isolating one indi- 
 vidual out of each successive generation, and he 
 found that a time came, after two or three 
 hundred generations, when the individual proto- 
 zoa seemed to deteriorate in size, to lose their 
 power of reproduction, and to die. 
 
 This seemed to suggest that mortality is really 
 inherent in the cell, and that old age and death 
 are inevitable for single-celled and many-celled 
 animals alike. 
 
 But many biologists refused to consider these 
 experiments as demonstrative. There were some 
 who believed that the decadence of Professor
 
 The Duel with Old Age 23 
 
 Maupas' protozoans was due to the development 
 of unfavorable conditions in the course of the 
 experiment. Further observations proved that 
 this was correct. Renewed experiments, in par- 
 ticular those of Enriquez, Woodruff, and Pro- 
 fessor H. S. Jennings, of Johns Hopkins, demon- 
 strated that if the food supply is properly 
 adjusted and the waste products are properly 
 removed from the medium in which the protozoan 
 lives, a strain of protozoa may be kept in perfect 
 health, without showing the slightest tendency to 
 degenerate, for thousands of generations, and pre- 
 sumably for an indefinite period. 
 
 So the idea that the normal single-celled organ- 
 ism is potentially immortal, and never comes to its 
 end except through violence, or what may be 
 termed disease, seemed experimentally estab- 
 lished. And the fact that protozoans under un- 
 favorable conditions develop disease and die 
 seemed to give renewed color to the idea that the 
 many-celled animals, including man, owe their 
 mortality to the development of unfavorable con- 
 ditions, rather than to any innate propensity to 
 die. 
 
 The Application to Man 
 
 Clearly to understand the logic of this at- 
 tempted applicaton of the life history of the 
 protozoan to the human organism, we must bear 
 in mind that every animal body, including that 
 of man, is built up exclusively of cells that by
 
 24 Adding Years to Your Life 
 
 themselves are not very different from the bit of 
 protoplasm that constitutes the body of the 
 protozoan. 
 
 It is an old axiom of physiology that all life 
 comes from an egg. The original egg from which 
 a human body develops is a miscroscopic bit of 
 protoplasm which the casual observer would not 
 very sharply distinguish from a protozoan. Like 
 the protozoan, this divides presently into two cells, 
 and then in succession into four, eight, sixteen, 
 and so on indefinitely. 
 
 But, unlike the offspring of the protozoan, the 
 new cells of the successive divisons of the human 
 embryo do not scatter in all directions and take 
 up individual existences. They remain clinging 
 together and form a larger and larger cluster. 
 Presently some of them assume different shapes 
 from others, though all sprang from the same 
 parent. In time some of their descendants are 
 grouped into clusters that we call muscles ; others 
 into structures we call bones, and the like. 
 
 All these structures, it must be recalled, are 
 direct descendants of the original egg-cell, and in 
 the main they retain the primitive function of 
 taking in nourishment, growing, and excreting 
 waste products. 
 
 But inasmuch as the various groups of cells 
 thus piled together to form organs are necessarily 
 shut off from direct contact with the medium 
 from which they absorb foodstuffs, it has become 
 necessary to build up, with the aid of other cells, 
 channels of communication through which the
 
 The Duel with Old Age 25 
 
 foodstuffs may be distributed. Thus the tubular 
 structures known as the intestinal tract, the blood- 
 vessels, lacteals, and lymphatics, bronchial tubes, 
 and glands, and kidneys and perspiratory ap- 
 paratus, have been developed. 
 
 All these are merely accessory mechanisms to 
 enable the remote cells of the body to gain a food 
 supply and to rid themselves of waste products. 
 
 The human body, then, may be closely likened, 
 in comparison with the protozoans, with the 
 human population of a city as contrasted with a 
 lone hermit in the country. The lone hermit, like 
 the protozoan, lives in direct contact with the 
 medium from which his foodstuffs are obtained. 
 He personally performs all the labor necessary 
 to his own maintenance. 
 
 But the city dweller, like the gregarious cell of 
 the developed body, is a specialist, performing 
 one or another type of labor and depending on 
 other specialists for the performance of other 
 necessary types. Some are day laborers, com- 
 parable to muscle cells; some are professional 
 workers, comparable to brain cells; some are en- 
 gaged in bringing in food products; others in 
 the removal of waste products. 
 
 Similarly the houses are of necessity con- 
 structed with streets between them to serve as 
 channels through which the food products may 
 be brought in and the waste products removed. 
 
 A city without these channels of communica- 
 tion would be as hopeless a proposition as a 
 human body without mouth or lungs.
 
 26 Adding Years to Your Life 
 
 Is Mortality the Price of Differentiation? 
 
 Let us bear this comparison between the human 
 body and the city population in mind and extend 
 a little further our reasoning from the life his- 
 tory of the protozoans. 
 
 Many of the most thoughtful of biologists who 
 have noted the potential immortality of the pro- 
 tozoan and the number includes Professor Jen- 
 nings, whose experiments were just referred to 
 are clearly of opinion that when the cells aggre- 
 gate together to form a single body, instead of 
 scattering individually, as do the successive 
 generations of protozoa, they create artificial 
 conditions that make indefinite existence impos- 
 sible. 
 
 Just as Professor Maupas' protozoa presently 
 degenerated and died because the experimenter 
 had failed to maintain ideal conditions of food 
 supply and of the removal of waste products, so, 
 according to these opinions, it is intrinsically 
 impossible in such a vast colony of cells as that 
 making up the human body, to maintain the ideal 
 conditions of food-supply and waste-removal 
 that are essential to maintenance of perpetual 
 health of the individual cells, and hence to peren- 
 nial youth and immortal life for the individual 
 organism. 
 
 These objectors argue that there can be no 
 great gain without some attendant loss. The 
 clustering of cells together to form a differen- 
 tiated body makes possible all the gains that lie
 
 The Duel with Old Age 27 
 
 between the life of a protozoan and the life of a 
 man. The loss involved is that of the primal 
 capacity of the protoplasmic cell to live in- 
 definitely. 
 
 " The higher diversified life is purchased at 
 the price of ultimate death." 
 
 According to this view, which is put forward 
 prominently by Professor Sedgwick Minot, of 
 Harvard, it is intrinsically impossible that such 
 a vast colony of cells as that making up the human 
 body should maintain the ideal conditions of food- 
 supply and waste-removal that are essential to 
 the maintenance of the perpetual health of the 
 individual cells, and hence to perennial youth and 
 immortal life for the aggregate body of cells 
 called a human being. 
 
 Thus, says Professor H. S. Jennings, in inter- 
 preting the theory, " Age and death, though not 
 inherent in life itself, are inherent in the differen- 
 tiation that makes life worth living." 
 
 Now it is obvious that if this view of the matter 
 is correct, the modern scientific quest of the 
 philosopher's stone is as chimerical an undertak- 
 ing as the voyaging of a Ponce de Leon. 
 
 But is this assumption necessarily valid? Is 
 it not a little like saying that the necessary penalty 
 of combining human habitations into cities is the 
 defective feeding of the population, defective 
 sanitation, and the attendant prevalence of dis- 
 ease and early average mortality? 
 
 Such were indeed the penalties of city life 
 throughout the Middle Ages and until compara-
 
 28 Adding Years to Your Life 
 
 tively recent times. The water supply of most 
 cities was defective and contaminated; the 
 methods of bringing food were crude and subject 
 to interruption; garbage and refuse were habit- 
 ually thrown into the streets to become a source 
 of contamination of the air and the breeding of 
 pestilence. Infant mortality was appalling; 
 plagues and epidemics were of perpetual recur- 
 rence; and it was necessary constantly to 
 replenish the city population from the country, 
 or the race of city dwellers would have died out 
 altogether. 
 
 But all this has been changed in our day. 
 
 Now, as everybody knows, life is nowhere more 
 healthful than in our large cities. Nowhere else 
 is the water supply in general purer; nowhere 
 else does one find better food supplied in more 
 abundant quantity ; nowhere else are the sanitary 
 conditions so good, and the systems of removing 
 waste products so hygienic and so effective. As 
 a consequence, nowhere else is the general health 
 better or the mortality rate lower than in our 
 well-managed cities. The death rate in New York 
 City is lower than in New York State outside the 
 city. 
 
 And all this has been brought about in defiance 
 of what seemed to our forefathers necessary con- 
 ditions deleterious to health and longevity inci- 
 dent to the very nature of city life. 
 
 ^And so the question naturally arises, may not 
 biologists of to-day be similarly in error when 
 they declare it impossible that the conditions of
 
 The Duel with Old Age 29 
 
 life for the cells of the human body should be 
 made so healthful as to give the cells a chance 
 for indefinite longevity! 
 
 Growing Tissues Outside the Body 
 
 Only the experiments of the future can deter- 
 mine the matter. But it seems to lie within the 
 possibilities, in view of the biological facts just 
 quoted, that the thing might ultimately be accom- 
 plished. In other words, it seems a justifiable 
 conclusion from the observed facts, that there is 
 no necessary limit to the activities of the aggre- 
 gation of matter that we call protoplasm. 
 
 It seems a fair inference that if we could make 
 the conditions in a human body so ideal that every 
 cell to the remotest tissue should be bathed in a 
 medium of blood and lymph containing just the 
 right proportions of food in just the needed quan- 
 tity, and supplying also ideal conditions for the 
 removal of waste products, we should have an 
 organism that would live on indefinitely. 
 
 That this inference is obviously in accord with 
 the traditions of the alchemist is of no particular 
 significance one way or the other. That it gives 
 support to the hopes and dreams of such inves- 
 tigators as Professor Metchnikoff, is a matter of 
 greater moment. 
 
 A review of the conditions as thus presented, 
 however, will make it clear, I think, to any 
 thoughtful reader that there is no probability 
 whatever that any single discovery, such as Pro-
 
 30 Adding Years to Your Life 
 
 fessor Metchnikoff's discovery of the function of 
 the glycobacterium, can by itself result in accom- 
 plishing the feat of giving the body eternal youth. 
 Whatever the importance of the waste products 
 in the intestinal tract, which the glycobacterium 
 is expected to neutralize, it would be absurd to 
 suppose that they are all-important. 
 
 There are questions of food supply, and of 
 elimination of waste products through other chan- 
 nels, that must obviously have consideration. 
 
 Until these are solved, we shall have taken only 
 the first step in the direction of maintenance of 
 perennial youth. 
 
 Fortunately we may record that just at the 
 moment there are new possibilities opening up 
 to the scientific investigator in this field, that are 
 of quite a different order from any hitherto avail- 
 able. This grows out of the extraordinary experi- 
 ments in the cultivation of living tissues outside 
 the body that have been carried out in recent 
 months by Drs. Carrel and Burrows, at the 
 Rockefeller Institute in New York. 
 
 These experimenters cut fragments of tissue 
 from the dead body of a chicken, or dog, or other 
 animal, and by supplying these tissues with a 
 proper medium, cause them to live and grow in 
 glass receptacles, keeping up cell-growth and 
 cell-division as if they were still a part of the 
 original parent organism. 
 
 In order to keep the tissues alive for long 
 periods, however, it is necessary, as might be 
 expected, not only to supply a medium having
 
 The Duel with Old Age 31 
 
 proper food qualities, but also to change this 
 medium from time to time, in order that the waste 
 products may be removed. In other words, the 
 conditions for these fragments of tissue outside 
 the body are precisely those that obtain in the cul- 
 tivation of the protozoans. The same essential 
 elements of pure food and complete elimination of 
 waste products must be fulfilled in order to main- 
 tain the life and health of the cell. Thus it is 
 demonstrated that the individual tissues of the 
 body do not necessarily die when the animal 
 ceases to breathe. 
 
 So far as can be judged, the tissues under glass 
 in Dr. Carrel's experiments would live in- 
 definitely. He even keeps bits of a heart beating 
 in his glass receptacles for months after the 
 creature from which the fragment was taken died 
 and was buried. 
 
 This clearly shows that it was not inability of 
 the heart-muscles to functionate that caused the 
 animal's heart to cease to beat. 
 
 The same thing is shown in another way by 
 the experiments of Dr. Meltzer, also of the Rocke- 
 feller Institute. He kills dogs and other animals, 
 and then restores them to life by artificial respira- 
 tion. His method has been applied to human 
 beings who had been suffocated in mines, and to 
 those who had been killed by an electric current. 
 
 All this new knowledge, then, seems to make it 
 clear that the death of any given individual by 
 no means necessarily implies that his tissues have 
 lost their inherent vitality. In the view of the
 
 32 Adding Years to Your Life 
 
 followers of Metchnikoff, it suggests that if just 
 the right conditions could be found, man need not 
 die except by accident including in the category 
 of accidents the attacks of specific diseases. 
 
 Putting the matter in its baldest form, the 
 question may be said to be reopened as to whether 
 the familiar phrase, " natural death," is not a 
 misnomer. 
 
 But is not the question answered, you say, in 
 the observed fact that all higher animals are 
 mortal? Not necessarily, replies the follower of 
 Metchnikoff; because it is by no means certain 
 that man or any higher animal ever does die a 
 strictly natural death. 
 
 That is surely a startling assertion, yet it will 
 bear close examination. The most casual inspec- 
 tion of mortality tables will show that the vast 
 majority of deaths are due to a small coterie of 
 allied diseases that have this essential common 
 factor : they are all caused by microbes which in- 
 vade the body and overwhelm the normal tissues. 
 
 Guests that Shorten Our Lives 
 
 Even under conditions of what is termed per- 
 fect health, the body is still the seat of myriads 
 of bacteria of many species, which grow and 
 thrive by untold billions on all the mucous sur- 
 faces of the mouth and digestive and respiratory 
 tracts. 
 
 These bacteria have such powers of reproduc- 
 tion that, if conditions were favorable, the
 
 The Duel with Old Age 33 
 
 progeny of a single one would increase in a few 
 weeks to such dimensions as to outbulk the entire 
 body of their host. They are kept from this dis- 
 astrous development only by the constant efforts 
 of the cells of the body in which they lodge. 
 
 Now these bacteria are protoplasmic cells that 
 feed on the same essential substances that nourish 
 the cells of the human body ; and in so far as they 
 thrive in the body they make the conditions of 
 life difficult for their host. 
 
 They not only absorb to their own use nutriment 
 needed by the body-cells, but they secrete waste 
 products that are deleterious in greater or less 
 measure to the human organism. 
 
 It is these poisons alone, in the view of Metch- 
 nikoff, that cause the decay and ultimate death 
 of the human tissues. But for the presence of 
 bacteria, in this view, the cells of the human body 
 would continue their functioning granted a 
 proper supply of food and normal conditions of 
 excretion indefinitely, just as do the isolated 
 cells of the protozoa in a sterile and properly 
 renovated culture medium. 
 
 But unfortunately the bacteria cannot be ex- 
 cluded. There is not a human being or a higher 
 animal of any kind that does not harbor in its 
 digestive tract a population of bacteria outnum- 
 bering the aggregate human population of the 
 globe since the race was developed. The labora- 
 tory worker is able to prove that protozoa are 
 immortal, because he is able to provide a medium 
 from which bacteria are excluded. But the ex-
 
 34 Adding Years to Your Life 
 
 periment cannot be duplicated with any higher 
 animal, because there is no conceivable way of 
 providing the body-cells with a sterile medium. 
 
 No way conceivable just at present, that is to 
 say. But may not the way be found? Is it not 
 possible that man may ultimately exterminate at 
 least such of the hosts of bacteria as live only in 
 his body? 
 
 It seems an almost hopeless task; yet it is true 
 that even now the more noxious microbes are be- 
 ing subordinated. In any contest it is much to 
 know just who are your real opponents. To-day 
 man knows, for the first time, who are the real 
 enemies of his prolonged existence. 
 
 Knowing our enemy, we are learning to fight 
 him. His deadliest cohorts represent a few chief 
 tribes, the members of which flourish exclusively 
 or mainly in the human body, producing there 
 adverse conditions that we personify and name 
 as if they were tangible personalities smallpox, 
 plague, tuberculosis, pneumonia, diphtheria, 
 cholera, typhoid fever, and the rest. 
 
 To-day preventive medicine is grappling with 
 these hosts, and seems in a fair way to banish 
 most of them. 
 
 A century ago smallpox claimed by death about 
 one-tenth of the entire population. To-day small- 
 pox has been virtually banished. 
 
 Twenty years ago diphtheria was the scourge 
 of childhood ; to-day it is held securely in check by 
 the antitoxin of Behring. 
 
 Ten years ago typhoid fever was a menace that
 
 The Duel with Old Age 35 
 
 threatened everyone ; to-day the vaccine of Wright 
 offers immunity to whoever cares to use it. 
 
 Four years ago syphilis seemed an unconquer- 
 able pest; to-day the " salvarsan " of Ehrlich 
 offers a specific that cures in a single dose. 
 
 A year ago cancer was the despair of the 
 physician; to-day there is at least the hope that 
 a remedy is being perfected in the hands of Von 
 Wassermann and Ehrlich. 
 
 Meantime such workers as Metchnikoff are 
 turning attention to microbes of that less virulent 
 type that have learned to flourish in the body of 
 their host without causing his early demise. 
 Metchnikoff 's newest experiment, as we have 
 seen, is to fight fire with fire, as it were, by intro- 
 ducing into the intestinal tract bacteria of a new 
 tribe to antagonize the poison-generating tribes 
 that are already quartered there. Even if he 
 succeeds, his results must be less spectacular 
 than the efforts directed against the quick-acting 
 disease-germs; yet the ultimate results may be 
 no less important as they have to do with the 
 definite prolongation of life. 
 
 Thus the men of science are closing in day by 
 day on the ranks of the noxious microbes. The 
 results are tangibly shown in the decrease of in- 
 fant mortality, the banishment of epidemics, the 
 lowered death-rate in cities, the making salubrious 
 of the Panama Canal region, the extraordinary 
 lengthening of the average period of life. Of the 
 individuals born in our generation, a higher per- 
 centage will reach patriarchal years than lived
 
 36 Adding Years to Your Life 
 
 through childhood in the days of our grand- 
 parents. 
 
 All this may not presage the actual banishment 
 of death, but it surely suggests that the scientific 
 search for the fountain of eternal youth has 
 proved a less futile and visionary quest than it 
 once seemed. 
 
 Learning the Needs of the Cells 
 
 If our enemy, the microbe, should finally be 
 held in check, it would remain to provide ideal 
 conditions of nourishment and elimination for 
 the cells of the body. And Dr. Carrel's new 
 method of cultivating tissues outside the body 
 offers hitherto unexampled opportunities for 
 learning the needs of the cells. 
 
 It will be obvious that when fragments of tissue 
 are thus cultivated, it becomes possible to test 
 the effect of different foodstuffs upon the growth 
 and health of the tissues in a way that was never 
 possible while the tissue was part of a complex 
 body. When time has been given for elaborate 
 sets of such tests, we shall know, as no one has 
 hitherto known, just what modifications of food- 
 stuffs are beneficial to different kinds of tissues. 
 We shall ultimately learn what quantities of food 
 supplies are required, and just what are the ab- 
 solutely normal conditions of the elimination of 
 waste products. 
 
 We shall then know, for example, whether a 
 meat diet or a vegetable diet is best for the human
 
 The Duel with Old Age 37 
 
 organism, or whether a mixed diet is better than 
 either. We shall know precisely what is the ulti- 
 mate effect on each kind of tissue of such auxiliary 
 foodstuffs and nerve stimulants as alcohol, to- 
 bacco, tea, coffee, and various condiments. In a 
 word, we shall have a really comprehensive and 
 scientific knowledge of the conditions of sanita- 
 tion and hygiene, so to speak, for the individual 
 cells of the human tissues. 
 
 Then it will be possible to put forward rules 
 of diet and exercise, and, on occasion of medica- 
 tion, that will establish approximately ideal condi- 
 tions for the organism as a whole. 
 
 It does not necessarily follow that we shall be 
 able to make these conditions so ideal as to give 
 the organism indefinite life. 
 
 It may be discovered, for example, that, in the 
 differentiated body politic of the human organism, 
 conditions that are ideal for one set of tissues 
 may not be ideal for another. Indeed, there is a 
 suggestion of this in the well-known fact that the 
 muscular system of the average man tends to 
 become old and decadent long before his brain 
 begins to decrease in power. 
 
 So it may happen that we can never make the 
 conditions just right for one set of cells without 
 making them wrong for another ; in which case we 
 cannot hope to give the body immortal life. 
 
 But whether or not there should prove to be 
 this limitation to the possible fulfillment of the 
 hopes of the modern alchemist, there can be no 
 question that it lies within the possibilities of
 
 3 8 Adding Years to Your Life 
 
 physiology and hygiene, even to-day, to improve 
 the conditions under which the average man 
 exists, so that life of the average individual may 
 be very greatly prolonged, and the resilient con- 
 ditions of youth maintained far into the period 
 that we now term old age. 
 
 What May Be Done To-day? 
 
 Whatever else the new studies teach us, they 
 show that all the tissues of the body should be 
 given opportunity for healthful functioning, and 
 all the channels of elimination kept freely in 
 operation. 
 
 Professor Metchmkoff himself believes that 
 there is little need of the services of his glycobac- 
 terium for persons whose diet is always what it 
 should be. I would add, provided the person ex- 
 ercises to a reasonable degree. Without such 
 exercise, I believe, it is impossible to keep up a 
 proper blood supply to all tissues, and to insure 
 a healthful degree of elimination. 
 
 Even with the best regimen and hygiene, and 
 ideal habits of exercise and rest, we cannot of 
 course hope that in our generation at any rate, 
 we shall be able to produce even approximately 
 ideal conditions in the bodily mechanism. No 
 sane person, therefore, supposes that Professor 
 Metchnikoff J s discovery, or any other that our 
 generation is likely to see, will solve the problem 
 of perennial youth, let alone that of perennial 
 life.
 
 The Duel with Old Age 39 
 
 But, on the other hand, no well-informed 
 physiologist doubts that the average man may 
 even now, by the application of knowledge clearly 
 in hand, ward off for a time the onset of old age, 
 and prolong the term of his years. A large coterie 
 of famous men of all ages from Sophocles, 
 JEschylus, and Euripides in antiquity, to Hum- 
 boldt, Gladstone, Bismarck, and many others in 
 modern times have demonstrated that by right 
 living it may be possible, without resort to lactic 
 bacilli or glycobacteria, to carry the strength, 
 vitality, intellectual acumen, and spirit of youth 
 into the seventh, eighth, and ninth decades. 
 
 Now that preventive medicine is banishing the 
 germs of contagious diseases that have been man's 
 chief enemies in the past, the number of men and 
 women who duplicate this record should increase 
 by leaps and bounds. 
 
 Perennial life would be perhaps a doubtful 
 blessing. But to remain young in spirit through- 
 out our mortal span never really to grow old 
 is a consummation devoutly to be wished for each 
 and every one of us. And this possibility, I con- 
 fidently believe, lies even now within the grasp of 
 every average individual. 
 
 To suggest practical means to effect this end, 
 for you and for your children, is the purpose of 
 the ensuing pages, which deal with different 
 aspects of the problem of attaining health, happi- 
 ness, and long life through attention to personal 
 hygiene.
 
 n 
 
 The Battle of the Microbes 
 
 FEW, if any, of us escape the occasional in- 
 halation or inhibition of the germs of tuber- 
 culosis. 
 
 If you have two children, there is more than 
 an even chance that at least one of them is infected 
 with these germs at the present moment, though 
 the germs give no evidence of their presence. If 
 your entire family comprises five individuals, the 
 chances are one to two that at least one member 
 will ultimately die of consumption since that dis- 
 ease is credited with ten per cent of all deaths. 
 
 It numbers more than three thousand victims 
 each week in the United States alone. 
 
 Nearly everyone has heard that smallpox 
 formerly killed one-tenth of the population, as 
 tuberculosis does now ; and that it pitted the faces 
 of a large proportion of the race, somewhat as 
 tuberculosis pits the lungs of the great majority 
 to-day. But after the celebrated Dr. Edward 
 Jenner discovered the efficiency of vaccination, 
 smallpox was soon under control. The disease 
 was estimated to have killed fifty million people 
 in Europe in the eighteenth century, just about 
 ten times the total population of the United 
 States at the close of that century. But since 
 
 40
 
 The Battle of the Microbes 41 
 
 Jennerian vaccination was introduced, smallpox 
 has been practically abolished except among un- 
 civilized peoples and the very ignorant classes. It 
 was so terrible a scourge that its name still excites 
 popular apprehension; but the disease itself has 
 no terror for anyone who chooses to avoid it. 
 
 Unfortunately there are enough ignorant and 
 bigoted and careless people in the world to keep 
 smallpox in existence ; but the frightful epidemics 
 that killed half the population of entire regions 
 can by no possibility recur among any people in- 
 telligent enough to avail themselves of the benefi- 
 cent privilege of vaccination. 
 
 In the same way tuberculosis, the great scourge 
 of our time, will some day cease to claim its ten 
 per cent of our race, for an immunizing virus is 
 certain to be discovered. Even if the vaccines 
 that are now being tested should prove disap- 
 pointing, there can be little doubt that someone 
 among the many investigators who are working 
 on the problem will finally attain success. But at 
 best a long time must elapse before the remedy 
 can be universally applied ; and one dare not pre- 
 dict the complete extirpation of this or any other 
 germ disease until people in general are much 
 more intelligently alive to their own interests 
 than they are at present. 
 
 Popular Apathy 
 
 The curious and discouraging fact is that most 
 people are strangely oblivious to the remediable
 
 4 2 Adding Years to Your Life 
 
 dangers that lie all about them, while they mani- 
 fest keen interest in spectacular calamities that 
 are far less momentous. 
 
 Thus everyone read with horror a few months 
 ago that ten thousand Turks were reported to 
 have fallen in a single battle with the Bulgarians ; 
 the newspapers scare-headed the accounts from 
 ocean to ocean. But no newspaper thought to 
 mention that many times ten thousand victims 
 had fallen on the same day before microbic foes 
 that are far more relentless than Turk or Bulgar. 
 The toll of infant lives alone amounts to about 
 forty thousand daily one at every other tick of 
 the clock, as a speaker at the recent International 
 Congress of Hygiene computed. 
 
 For the most part these infants are slaughtered, 
 in the sense that they fall victims to preventable 
 diseases. 
 
 But the thing is too familiar to excite interest. 
 It is hard to make a news item out of something 
 that occurs every day. 
 
 Doubtless the chief cause of public apathy as 
 to the slaughter of the innocents, however, results 
 from lack of general understanding of the condi- 
 tions of the one-sided combat in which the infants 
 are vanquished. The mother who sends her infant 
 to its grave does not do so wilfully ; she acts only 
 through ignorance. And the general public, 
 which reads with complacency Professor Irving 
 Fisher's estimate that six hundred and thirty 
 thousand preventable deaths occur in this country 
 each year, is complacent simply because of its
 
 The Battle of the Microbes 43 
 
 ignorance. It does not clearly apprehend what is 
 meant here by the word " preventable." The old 
 idea about the " visitation of Providence " still 
 gives consolation to thousands of mothers who 
 have really administered the death-potion to their 
 infants with their own hands. 
 
 Knowledge as to the true and tangible cause of 
 death is so new that physicians are only beginning 
 to grasp it, and the general public cannot be sup- 
 posed to have gained more than a vague inkling 
 of it. 
 
 Legions of Enemies 
 
 It is perhaps not superfluous, then, to remind 
 the reader that the vast majority of all deaths 
 are due to the invasion of the human body by 
 definite and tangible foes, which are no less real 
 because they are of microscopic dimensions. The 
 chief aim of medical science in our day is to com- 
 bat these microbes, either by preventing their 
 access to the body, or by making the body proof 
 against them if they do find entrance. 
 
 Thus when we say that a person has consump- 
 tion we mean that a microbe of a definite species, 
 which we name the tubercle bacillus, has lodged 
 in the lungs, and is flourishing there. 
 
 Similarly typhoid fever is a condition induced 
 by colonies of the typhoid bacillus in the large 
 intestine; diphtheria means a poisoning of the 
 system by the secretions of a colony of Klebs- 
 Loeffler bacilli in the throat, and so on. 
 
 We speak of the microbes that produce these
 
 44 Adding Years to Your Life 
 
 untoward results as " malignant "; but of course 
 this is a biased view of their activities. The bacilli 
 may cause the death of their host, but it is by no 
 means to their advantage to do so. They have 
 colonized in his lungs or digestive tract or throat 
 "because they found lodgment there convenient, 
 and they can multiply and flourish only in a warm 
 place. So if they increase with such ill-judged 
 rapidity as to cause the death of their host, they 
 must presently die also, being powerless to escape. 
 
 Instead of malignant, we might better describe 
 these microbes as foolish. 
 
 There are sundry wiser members of the tribe 
 that have learned to colonize the human body 
 without being obviously harmful; at least without 
 causing the death of their host. Some fifty dif- 
 ferent species or varieties of these peaceful 
 microbes may be found on occasion flourishing in 
 the salivary juices of the mouth; and legions of 
 them are always present in the intestinal cavity. 
 Their host, far from being made violently ill by 
 them, is blissfully oblivious of their existence. 
 
 And yet these " benevolent " bacteria, no less 
 than the " malignant" ones, are perfectly 
 tangible creatures, of definite size, form, and 
 contour. 
 
 If you were to moisten a glass slide with your 
 tongue and place it in the field of a microscope, 
 you might witness the activities of a strange and 
 varied company of fellow-citizens. You would 
 see that some tribes are shaped like tiny rods. 
 These are called bacilli. Others are mere dots,
 
 The Battle of the Microbes 45 
 
 like infinitesimal droplets of water. These are 
 called micrococci. Yet others resemble tiny cork- 
 screws, and are called spirilla. These are the 
 three main tribes of bacteria, each tribe having 
 many species, which, however, closely resemble 
 one another in general appearance. The largest 
 of them come within the range of vision only when 
 magnified by a powerful lens; and the smallest 
 ones that have been observed are barely visible 
 specks when amplified by a thousand diameters. 
 
 A man similarly magnified would appear more 
 than a mile in length. 
 
 Yet the most infinitesimal microbe, when banded 
 with his fellows, may prove more than a match for 
 the man. Indeed, it almost seems as if the microbic 
 virulence increased with diminishing size ; for the 
 malignant varieties are mostly far smaller than 
 many benevolent ones; and the germs of several 
 very malignant diseases, including smallpox, 
 scarlet fever, and hydrophobia, escape detection 
 under the most powerful microscope. They ap- 
 pear to be able to pass through the meshes of a 
 porcelain filter. 
 
 Thus they are unthinkably small ; yet they are as 
 deadly as cannon balls. 
 
 Treacherous Half-Tamed Legions 
 
 Among the hosts of " peaceful " microbes that 
 appear in the drop of saliva you have placed on 
 the microscope slide, there may be some that are 
 by no means so harmless as their presence in the
 
 4 6 Adding Years to Your Life 
 
 mouth of a person in perfect health might seem 
 to argue. 
 
 More than likely there are goodly numbers of 
 pneumococci, the germs of pneumonia; and al- 
 most certainly there are hosts of streptcocci and 
 staphylococci, the pus-forming microbes and the 
 agents of blood poisoning. All these may flourish 
 in your mouth without causing you obvious injury 
 or inconvenience. They seem quite friendly and 
 harmless. But in reality they are treacherous 
 ingrates; for, even as they bivouac under a flag 
 of truce on your bodily surfaces, exterior and in- 
 terior, they are forever on the lookout for an op- 
 portunity to invade your blood-stream and lymph- 
 spaces ; and when the opportunity comes, they will 
 wage a guerrilla warfare as ruthless as that waged 
 by any one of the frankly hostile bacteria. 
 
 Suppose, for instance, that you chance to be 
 exposed to inclement weather some day, and be- 
 come thoroughly chilled. Your temperature is 
 lowered for the moment; your vitality below par. 
 That moment of weakened defense will quite prob- 
 ably be seized on by the pneumococcus to invade 
 your lungs; and you will be stricken with pneu- 
 monia. 
 
 Or suppose that a company of diphtheria bacilli 
 find their way into your throat. The hostile 
 colony will at once be agumented by recruits from 
 the ranks of the streptococcus always loitering 
 in your mouth who will help to form a character- 
 istic " false membrane," and if possible will in- 
 vade the tissues, and induce blood poisoning.
 
 The Battle of the Microbes 47 
 
 Then, too, the streptococci can live on the sur- 
 face of your body. Doubtless there are myriads 
 of them on the hand with which you hold this book. 
 When a cut or wound, small or large, develops 
 an angry, ulcerated surface, the presence of 
 streptococcus and his allies is demonstrated. In 
 warfare it. is not bullets that kill most soldiers, 
 even those that fall wounded on the field. It is 
 streptococcus, and his close relative, staphylo- 
 coccus, which invade a wound, otherwise perhaps 
 not serious, and produce suppuration and 
 gangrene. 
 
 It is these germs that find their way into the 
 blood-stream, causing blood poisoning, and pres- 
 ently completing the deadly work of bullet and 
 bayonet. 
 
 Even with no external lesions to give them free 
 access to the tissues, these omnipresent microbes 
 may on occasion find their way into pores or ducts 
 in the skin, causing boils, carbuncles, stys, or 
 local abscesses. In pulmonary tuberculosis they 
 are the chief cause also of the ulcers in the lungs 
 that induce hemorrhage and ultimately death it- 
 self. They are a prime, if not the exclusive, cause 
 of erysipelas; and in smallpox and scarlet fever 
 their activities produce complications of serious 
 and very often of fatal character. Wherever they 
 gain entrance, the symptoms of blood poisoning 
 supervene. In one-third of all deaths, from what- 
 ever primary cause, streptococci may be found in 
 blood taken from the heart. They may cause a 
 malignant inflammation of the lining membrane
 
 48 Adding Years to Your Life 
 
 of the heart itself; and they have an active share 
 in hastening the end of patients suffering from 
 diabetes and other supposedly non-bacterial 
 maladies. 
 
 First and last, the streptococcus has had a hand 
 in more human deaths, probably, than are to be 
 charged against any other single agency whatso- 
 ever. 
 
 And all this, be it understood, refers to a mi- 
 crobe that has been said to be semi-domesticated 
 because it is always present everywhere on our 
 skins and in our mouths ; however unfamiliar his 
 name may be to his average host. 
 
 The Body a Fortified Castle 
 
 But if, then, microbes of such malign possibili- 
 ties are not merely all about us but all over us 
 on your skin and mine, under our finger nails, in 
 our mouths how do any of us escape being 
 stricken down by them even for a single day or 
 hour? 
 
 The answer gives an insight into strange func- 
 tions that until recently were quite unsuspected. 
 It reveals the human body as a fortified citadel, 
 guarded at every vulnerable point, without and 
 within, by walls that to the enemy are well-nigh 
 impenetrable ; and garrisoned with legions of war- 
 riors ever on the alert to attack any intruder that 
 makes a breach in the fortifications and finds en- 
 trance. 
 
 Such language may seem figurative. In reality
 
 The Battle of the Microbes 49 
 
 it expresses the precise conditions that prevail. 
 The invading hosts have been named, and the 
 character of their onslaught suggested. The bar- 
 riers that hold them at bay the walls and barri- 
 cades of the human fortress are the skin without 
 and the mucous membranes within the cavities of 
 the body. 
 
 The soldiers that stand ready to attack the 
 microbic invaders are the white blood-corpuscles, 
 or leucocytes, that everywhere swarm in the 
 blood- and lymph-channels. 
 
 If you were to prick the tip of your finger with 
 a needle, and place the tiny droplet of blood that 
 exudes on a microscope slide, you would see thou- 
 sands of these leucocytes distributed here and 
 there in the blood, in the midst of the millions of 
 red blood-corpuscles. You might recognize them 
 at once by their relatively large size. They ap- 
 pear practically colorless, like a drop of white of 
 egg; but a visible nucleus shows that they have a 
 definite structure; and the way they move about, 
 slowly changing shape and, as it were, flowing in 
 one direction or another, shows clearly that they 
 are alive. They closely resemble in appearance 
 and manner the lowly single-celled organism 
 called the amoeba, which you may have seen under 
 the miscroscope in a drop of impure water ; and it 
 is a trifle disconcerting to observe that there are 
 thousands of these creatures in the tiniest drop 
 of normal blood. 
 
 But you owe not merely health but life itself to 
 them.
 
 50 Adding Years to Your Life 
 
 The Battle in the Blood-Stream 
 
 If you wish to see for yourself what manner of 
 service the leucocyte performs for you, nothing 
 more is necessary than to insert a needle-point in 
 a culture of bacteria say, in your own mouth 
 and convey a colony of microbes to the drop of 
 blood you are examining. It will then be clear 
 that the leucocyte is a creature of ferocious nature, 
 who regards every bacterium as a mortal enemy, 
 which must be fallen upon and literally devoured. 
 You will see the leucocyte flow about the bacteria 
 and engulf them bodily, one after another; and 
 the remains of the victims will be visible within 
 the transparent body of their devourer, until they 
 gradually undergo digestion. 
 
 Owing to this extraordinary habit, the leuco- 
 cytes were christened phagocytes, or cell-eaters, 
 by Professor Elie Metchnikoff , who first witnessed 
 this strange battle in the blood, and interpreted 
 its beneficent meaning. 
 
 You might witness such a fight as this not only 
 in a drop of your own blood, but in the living 
 tissues of the web of a frog's foot if touched with 
 an infected needle-point; or, to better advantage, 
 under high powers of the microscope, in the thin 
 mesenteric (intestinal) membrane of an anesthet- 
 ized mouse. 
 
 At first glance the contest will seem an unequal 
 one. The invading bacteria are but pigmies be- 
 side the militant defenders. Streptococci are so 
 small, for example, that a regiment of two thou-
 
 The Battle of 'the Microbes 51 
 
 sand of them, ranged up in line, would be required 
 to span the letter " o " as printed on this page. 
 The typhoid bacillus would require half an hour's 
 time to cross the same space, though it propelled 
 itself (as its cilia enable it to do) more than three 
 times its own length each second. The influenza 
 bacillus is so infinitesimal that if the warriors of 
 his clan were neatly marshaled in compact order, 
 more than six billion of them could be quartered 
 on the surface of a square inch. 
 
 To such Lilliputians, the white blood-corpuscle, 
 about two thousand five hundred of which could 
 span an inch, must seem colossal. 
 
 But the bacterium, though outclassed in size, is 
 by no means helpless. The noxious members of 
 the tribe are endowed with some chemical or 
 physical property, the exact nature of which we 
 do not know, that enables them to repel the 
 leucocyte and strangely escape being engulfed in 
 its body. Such at least is often the case. 
 
 The cells of the body, however, under stimulus 
 of the presence of a hostile bacterium, can secrete 
 certain chemicals that break down the bacterial 
 defense, and put the microbe at the mercy of the 
 leucocyte. 
 
 When such chemicals have been secreted into the 
 blood (or when they have been artificially intro- 
 duced) the bacteria are weakened, and the leuco- 
 cytes will be seen, under the microscope, to throw 
 themselves upon the microbes and devour them, 
 ultimately digesting their remains. 
 
 The extent to which the leucocytes are able to
 
 52 Adding Years to Your Life 
 
 do this very largely determines the relative safety 
 of any given individual against the attacks of a 
 microbic host. 
 
 Billions of Combatants 
 
 The conditions of the fight will be better under- 
 stood if we reflect that the invading microbes, 
 when they gain entrance to the blood at all, are 
 likely to come in hordes of unthinkable numbers, 
 and are able to reproduce their kind, and thus fill 
 up gaps in their ranks, with appalling rapidity 
 when they find favorable conditions. A baterium 
 born this moment may become a grandparent 
 within an hour. That is to say, it may have di- 
 vided itself into two individuals, and these two 
 may have divided to make four. And this process 
 may proceed, if conditions continue favorable, 
 with the cumulative speed that renders a geo- 
 metrical ratio always so startling. 
 
 At the end of forty-eight hours, it has been esti- 
 mated, a single bacterium may have descendants 
 to the number of 281,500,000. 
 
 In another day, the number would be beyond 
 computing; but the aggregate bulk of the family 
 composed of individuals that could lodge by 
 millions on your finger-tip without your knowing 
 of their presence would be, as Dr. Jordan as- 
 sure us, more than seven thousand tons! 
 
 With such figures in mind, we may gain some 
 notion of the task that is cut out for the white 
 blood-corpuscles when a bacterial army invades
 
 The Battle of the Microbes 53 
 
 their stronghold. The foe may come by billions, 
 though their medium be but a few drops of con- 
 taminated water or milk; and it is obvious that 
 no time is to be lost if they are to be prevented 
 from absolutely overwhelming the body by mere 
 force of numbers, to say nothing of the toxic 
 effects of their secretions. 
 
 But the defending leucocytes constitute a host 
 of prodigious numbers also. It is evidence of the 
 stressful conditions under which we live that there 
 is a garrison of about one hundred thousand 
 leucocytes at all times in every drop of blood in 
 our bodies. 
 
 They constitute a standing army numbering 
 more than fifty billion, in the blood-system of 
 every human being. 
 
 The maintenance of such an army, eternally 
 vigilant, is the price of life itself in this microbe- 
 haunted world. There is no hour of the day when 
 the system may not be invaded by one or another 
 of the bacterial hosts that are ever garrisoned on 
 the other side of the thin walls of the skin and 
 mucous membrane. 
 
 A mosquito or a flee or a tick or a bedbug may 
 drill a hole through the wall, and introduce a regi- 
 ment of germs of malaria or plague or con- 
 tagious fever. 
 
 A chance nail puncture may bring deep into 
 the tissues a colony of streptococci or the deadly 
 microbe of tetanus (lockjaw), which abounds al- 
 most everywhere in the soil. 
 
 A slight fissure in tonsil or pharynx may give
 
 54 Adding Years to Your Life 
 
 opportunity for the streptococcus and his allies to 
 enter tissues in which they can multiply with as- 
 tonishing rapidity. 
 
 Or the coign of vantage from which the attack 
 is made may lie in a remote lobule of the lung, 
 or in the intestinal tract ; such being the favorite 
 seats of action of tubercle and typhoid bacilli, re- 
 spectively, to name but two enemies among many. 
 
 Details of the Combat 
 
 So it is absolutely essential that the leucocytes 
 should at all times be posted in numbers, behind 
 every inch of the fortifying but not quite im- 
 pregnable walls. 
 
 It is essential also that they should constitute a 
 mobile army, capable of being concentrated at any 
 given point where an attack of unusual virulence 
 is sustained. The position of the leucocytes as 
 normally distributed throughout the blood-stream 
 enables them to fulfil these conditions ideally. 
 They are always present as a defending garrison 
 about every cell of the entire body ; and when any 
 localized attack of microbes is reported, there is 
 an instant reinforcement of the troops at that 
 point supplied from the neighboring blood- 
 channels. 
 
 Should there be a cut in the flesh, for example, 
 or a bullet wound, which is " infected," the sur- 
 rounding tissues become swollen and red " in- 
 flamed," as the saying is. 
 
 This means that the blood-vessels have become
 
 The Battle of the Microbes 55 
 
 patulous, their blood-current slackened, to give 
 lodgment to ever-increasing bands of leucocytes 
 that are being mobilized there to contest every 
 millimeter of the exposed territory with the in- 
 vading microbes. How recklessly they throw 
 themselves into the breach is shown by the fact 
 that the pus which presently gathers and flows 
 from the wound is composed largely of the bodies 
 of leucocytes that, in their eagerness to pursue 
 the enemy, have, so to speak, fallen outside the 
 broken fortifications. 
 
 Until a few years ago, no one understood the 
 nature of this contest. The surgeon regarded in- 
 flammation as a necessary part of the process of 
 healing wounds. He talked of "laudable " pus, 
 and was well content if the discharge from a 
 wound was free from the bad odor that might 
 portend the onset of hospital gangrene. But 
 to-day Listerism has changed all that. 
 
 Now that the condition is understood, the sur- 
 geon knows how to deal with it. 
 
 He takes good care to see that no microbes 
 follow in the track of his scalpel. Everything 
 that he uses in an operation has been treated 
 with antiseptics or boiled and steamed in a ster- 
 ilizer. If he is called to an accident case, in which 
 germs have already invaded a wound, he kills the 
 germs with an antiseptic solution, and dresses the 
 wound with " sterile " that is to say, germ-free 
 gauze, to prevent any further invasion. The 
 old-time surgeon unwittingly left the entire treat- 
 ment of a wound practically in the hands of the
 
 5 6 Adding Years to Your Life 
 
 militant leucocytes (though he had no notion that 
 he was doing so) ; the present-day surgeon shuts 
 out the enemy, and makes the presence of the 
 leucocytic host almost superfluous. 
 
 i 
 
 Reinforcements for the Warriors 
 
 What the surgeon, dealing with visible lesions, 
 accomplishes with his antiseptics, the physician 
 must undertake in quite another way when called 
 upon to aid the leucocytes in fighting germs that 
 have made their way into the general blood-stream 
 and are swarming perhaps in the juices of every 
 tissue. 
 
 For two or three microbes only are antiseptic 
 drugs known that can be given in sufficient quan- 
 tities to kill the remotely scattered germs, with- 
 out at the same time killing the patient. 
 
 But another way of attacking the problem is 
 to attempt to aid the body in strengthening its 
 normal defenses. In many cases this may be ac- 
 complished by developing so-called viruses 
 antitoxins and vaccines that are deleterious to 
 specific microbes. These viruses are developed 
 only through use of the specific germs themselves. 
 The antitoxins, of which the remedy for diph- 
 theria is the best-known example, are secured by 
 inoculating a horse with a liquid in which a cul- 
 ture of diphtheria baccili has been grown. After 
 repeated inoculations, the blood of the horse is 
 found to be charged with an antidote to the diph- 
 theria poison, and a portion of serum from the
 
 The Battle of the Microbes 57 
 
 blood of the horse constitutes the beneficent 
 remedy which, since its introduction by Dr. Emil 
 von Behring less than twenty years ago, is 
 credited with saving millions of human lives. 
 
 In the old days, more than half the diphtheria 
 victims died ; in our day the serum saves nine out 
 of ten. 
 
 Not fewer than seventy-five thousand lives are 
 thus saved annually in the United States alone. 
 
 Of vaccines, the familiar examples are that de- 
 veloped in the body of the cow, and used so ef- 
 fectively against smallpox, and the anti-rabic 
 vaccines used at the Pasteur Institutes. The 
 newest type of vaccine-therapy calls on the in- 
 dividual human patient to develop his own anti- 
 dotes, and it induces conditions that enable him 
 to do this safely and effectively. The therapist 
 makes a culture of a specific disease-germ in the 
 laboratory test-tube. He then kills the microbes 
 by heating them, and with a hypodermic syringe 
 injects a few million of their bodies into the tis- 
 sues of the human subject. 
 
 Such a wilful inoculation of a patient with 
 virulent disease germs seems at first sight a 
 hazardous experiment. 
 
 But the microbes are injected in limited num- 
 bers, and, being dead, they cannot add to their 
 number by reproduction. So the tissues are able 
 to cope with them, producing the specific anti- 
 dotes which neutralize the bacterial poisons and 
 either destroy the bacteria themselves or render 
 them susceptible to the attacks of the leucocytes.
 
 58 Adding Years to Your Life 
 
 The substance, known only through its effects, 
 that produces the latter result was named 
 " opsonin " (from a Greek word meaning, to make 
 palatable) by its discoverer, Sir Almroth Wright. 
 A test of the rapidity with which the leucocytes eat 
 any given germs in the blood of a patient based 
 on an actual count is called the determination 
 of the " opsonic index." Where opsonin is ab- 
 sent, the leucocytes are inactive; where present 
 the militant defenders launch themselves on the 
 enemy, and devour them with avidity. Any 
 person is immune, or relatively immune, to a 
 given bacterial disease if his opsonic index is 
 high. 
 
 If your system contains enough of the opsonins, 
 you are virtually germ-proof. 
 
 Wide Scope of the Vaccine Treatment 
 
 The utility of the vaccine treatment is not con- 
 fined to preventive measures. It is now being 
 applied as a curative measure also, after patients 
 are stricken with disease. The utility of the 
 method is particularly obvious in the case of 
 localized infections. Here, let us say, is a focus 
 of tubercle germs in the lungs, or of germs of 
 malignant endocarditis in the lining membrane 
 of the heart. The local tissues fight bravely, but 
 are unable to gain a decisive victory; the unwel- 
 come microbes hold their own, or increase in 
 number. But the vaccine therapist he is usually 
 termed an immunisator comes to the rescue, by
 
 The Battle of the Microbes 59 
 
 injecting into the patient's arm or leg a dead 
 culture of microbes. 
 
 This sets up a vigorous local production of 
 antidotes, the excess of which enters into the gen- 
 eral blood-stream, finds its way to the local tissues 
 where the fight is going on, and constitutes a re- 
 inforcement that may turn the tide of battle. 
 
 The vaccine treatment has great popular 
 interest, not only because of results achieved with 
 such deadly maladies as typhoid fever, tubercu- 
 losis, and pneumonia, but because it is now being 
 applied by Sir Almroth Wright and his followers 
 to the treatment of a great number of minor ail- 
 ments which, in their totality, so Sir Almroth 
 contends, make up nine-tenths of human disease. 
 
 Common colds, recurrent influenza, sore throat, 
 chronic bronchitis, boils, carbuncles, ulcerated 
 teeth, and even stys and pimples come within the 
 range of the new treatment. 
 
 In stubborn cases, the germs used to make the 
 culture are taken from the infected area of the 
 individual patient to be treated, constituting a 
 so-called autogenous virus. Specific or individual 
 treatment is thus carried to its limits. 
 
 The results are sometimes very remarkable. 
 When the treatment has come into general use, it 
 will be possible, Dr. Wright believes, to give the 
 average man immunity from the particular type 
 of minor ailment to which he is subject, no less 
 than to give him protection against the attacks 
 of the more virulent microbes. 
 
 Coupled with these curative and immunizing
 
 60 Adding Years to Your Life 
 
 methods is the work of the modern sanitarian, 
 who effects a flank movement of inestimable im- 
 port by establishing quarantine service, by fumi- 
 gating infected quarters, and by destroying the 
 living carriers of germs mosquitoes, flies, ticks, 
 fleas, bedbugs, rats, mice, and ground squirrels. 
 All these measures look to the single end of mak- 
 ing life hard for the noxious microbe ; and enough 
 has already been accomplished to warrant the 
 prediction that these infinitesimal but all-powerful 
 enemies of our race will play a far less important 
 role in the future history of mankind than they 
 have played in the past. 
 
 Some Rules for Health 
 
 Not to be misled into undervaluing our an- 
 tagonist, however, it is well to recall that, despite 
 the justly applauded triumphs of modern medi- 
 cine, microbic diseases still cause the death in the 
 United States of at least one hundred individuals 
 each and every hour of the day, year in and year 
 out. 
 
 With such a menace as that confronting us, it 
 may well be asked what any given individual may 
 do to safeguard himself and his family against 
 the universal enemy. 
 
 I shall answer the inquiry in the briefest terms, 
 with a few practical suggestions : 
 
 Be vaccinated against smallpox. The vaccine 
 virus is developed in the system of a cow or calf. 
 As developed by modern health boards it is free
 
 The Battle of the Microbes 61 
 
 from contamination, and it gives immunity against 
 a disease that was formerly one of the worst of 
 scourges, claiming one-tenth of the population by 
 death. Have your children vaccinated in infancy, 
 and revaccinated every six or seven years, or 
 whenever there is possibility of infection. 
 
 Be inoculated against typhoid fever, if you have 
 occasion to travel in a region where hygiene is 
 not under scientific control, or where for any 
 reason you mistrust the sanitary conditions in 
 general. 
 
 Take anti-rabic treatment at the nearest Pas- 
 teur Institute, should you have the misfortune 
 to be bitten by a dog or cat suspected of having, 
 or known to have, hydrophobia. The anti-rabic 
 virus is developed in the system of a rabbit. Its 
 efficacy in preventing hydrophobia or rabies is 
 unquestionable ; but it is unavailing as a curative 
 measure after the disease has actually manifested 
 itself. Fortunately rabies has a long incubation 
 period, so there is time to take the preventive 
 treatment. 
 
 Treat minor wounds, particularly those caused 
 by puncture from a soiled or rusty nail, with re- 
 spect. Go at once to a doctor and have the wound 
 properly treated. It is foolhardy to take chances 
 with the bacillus of lockjaw. 
 
 Have your physician recommend an antiseptic 
 spray or douche for nose and throat. Keep this at 
 hand in an atomizer, and use from time to time, 
 more or less as a matter of toilet routine; but 
 particularly as an added precaution when influ-
 
 62 Adding Years to Your Life 
 
 enza is epidemic, or when you have been exposed 
 to bad weather or subjected to fatigue. 
 
 Never sit down with wet feet or moist apparel. 
 If your stockings have been damp, remove them 
 at once when you get home, and heat the feet 
 thoroughly, toasting them for some time before 
 stove, radiator, or grate. Put on dry clothing, 
 and do not leave the fire until you are thoroughly 
 warm. Also use an antiseptic say, peroxide of 
 hydrogen with thoroughness as a mouth wash. 
 The germs of pneumonia sometimes lodge in the 
 mouth without doing harm ; but a slight lowering 
 of the bodily temperature may enable them to 
 develop, and, finding their way to the lungs, to 
 set up the inflammatory condition constituting 
 pneumonia, a disease that is responsible for more 
 than a hundred thousand deaths in the United 
 States each year. 
 
 Pneumonia has been developed experimentally 
 in fowls by having them stand with their feet in 
 a stream of cold water. You are in similar danger 
 whenever your temperature is lowered for a pro- 
 longed period. But the active measures above 
 suggested will usually ward off the danger. 
 
 If you are persistently subject to some minor 
 microbic disorder, such as boils, pimples, acute 
 colds, chronic bronchitis, consider the advisability 
 of taking the vaccine treatment to fortify your 
 system against the microbe that is your particular 
 pet aversion. The temperamental condition that 
 makes you especially susceptible to this particular 
 germ may perhaps be overcome in this way. The
 
 The Battle of the Microbes 63 
 
 condition of the system that leads to the recur- 
 rence of boils or to the persistence of open sores 
 and ulcerative lesions, is peculiarly amenable to 
 the vaccine treatment. 
 
 Act on the belief that in the last analysis the 
 best protection against the microbes is the rugged 
 condition of your own system. We have seen 
 how the tissues of the body fight any noxious 
 microbes that intrude upon them. Let it be under- 
 stood that the vigor and efficiency with which the 
 tissues act in this defensive campaign depend 
 very largely upon the healthy tone of the tissues 
 themselves. A ruggedly healthy organism, if not 
 subjected to the depressing effect of overexertion 
 or worriment, may be practically immune to al- 
 most every type of microbe. 
 
 So all measurements that make for the improve- 
 ment of general bodily health are germicidal 
 measures. 
 
 Eat nourishing food in sufficient quantity, but 
 do not overeat. 
 
 Get as much fresh, outdoor air as you can, day 
 and night. 
 
 Exercise sufficiently to keep your muscles in 
 tone and your blood in good circulation. Well- 
 toned muscle-cells are practically germ-proof; 
 and an active blood-stream scatters any focus of 
 intruding microbes so widely that the white blood- 
 corpuscles and organic germicides have the best 
 chance to overcome the enemy. 
 
 Bathe regularly and rationally, but not to ex- 
 cess. Use tepid or warm water, but end always
 
 64 Adding Years to Your Life 
 
 with a cold spray or sponge bath, to tone the skin. 
 The cold spray, properly graduated, is a skin- 
 toughener and general tonic of positive value not 
 merely in the prevention, but in the regular treat- 
 ment of microbic diseases, including in particular 
 tuberculosis. 
 
 Avoid the two great depressants, alcohol and 
 worry. These are out-and-out allies of the mi- 
 crobe. Alcohol lowers the tone of the system, 
 decreases the power of resistance, and thus invites 
 microbic diseases. Athletes in training never use 
 it. Arctic explorers have learned that it handi- 
 caps them. People in everyday life who wish to 
 maintain maximum efficiency, including maximum 
 resistance to disease, will do well to take a leaf 
 from the experience-book of athlete and explorer. 
 
 All these measures look to the combating of the 
 microbic hosts after they actually invade your 
 body. But it is equally the part of wisdom to 
 guard your body as much as may be against 
 needless exposure to attack. However good your 
 defensive armor, you are obviously safest when 
 beyond reach of the enemy's guns. And in par- 
 ticular you should guard your children, whose 
 immaturity makes them peculiarly susceptible, 
 and who cannot guard themselves. 
 
 Give the Sunlight a Chance 
 
 A prominent channel by which microbes find 
 entrance into our bodies is the air we breathe. 
 Bacteria exist by millions in every pinch of dust
 
 The Battle of the Microbes 65 
 
 of the city street ; they swarm in the dust that the 
 whole family inhales when the housemaid sweeps 
 or beats a carpet. They settle on bread as it comes 
 from the bakery. We cannot possibly hope to 
 escape ingesting a certain number of them. But 
 there are ways in which we can minimize the 
 number and in large measure avert the danger. 
 
 To that end, it should be known to everyone 
 that the one thing which no hostile bacterium can 
 face unflinchingly is sunlight. 
 
 The beneficent rays of the sun, which give life 
 to ordinary plant-cells and set them in action, 
 blast the living content of the bacterial cell, like 
 shafts of lightning. 
 
 The particular light-beams that have this dis- 
 astrous effect on the microbe are the short waves 
 beyond the visible spectrum, the so-called ultra- 
 violet rays. Medical science has taken advantage 
 of the knowledge that these rays will kill bacteria, 
 in the treatment of certain local infections. The 
 Finsen-ray lamp, by which the local tubercular dis- 
 ease known as lupus may be cured, utilizes this 
 ultraviolet ray. The newest type of Finsen lamp 
 operates with the quartz lamp invented by Mr. 
 Peter Cooper Hewitt; which lamp, it may be 
 added, is similarly used to purify water and milk, 
 by destroying the contaminating bacteria. 
 
 What the Finsen and Hewitt lamps thus accom- 
 plish on a small scale is perpetually done in a 
 colossal way by the sun. Whenever sunlight 
 penetrates for any considerable length of time, the 
 bacterial inhabitants are destroyed. If it were
 
 66 Adding Years to Your Life 
 
 no t so if the bacteria could develop resistance to 
 the blighting influence of sunlight mankind 
 would soon find the contest with the microbe a 
 hopeless battle, and our race would probably dis- 
 appear from the face of the globe. 
 
 There follows the obvious moral : Let there be 
 light in your household wherever and however 
 you can manage it. 
 
 Keep your children out in the sunlight. 
 
 If you live in the city, utilize the housetops. 
 
 Also let the outdoor air, sterilized by sunlight, 
 into your dwelling day and night. Open-air hos- 
 pitals cure thousands of advanced cases of tuber- 
 culosis. High up in the Alps children are kept 
 naked in the sunlight, out of doors, when the 
 ground is covered with snow. Such heroic treat- 
 ment must be worked up to gradually, of course ; 
 but in the end the children enjoy it ; and it cures 
 infections that resist every other remedy. 
 
 Open-air treatment in the sunlight, combined 
 with judicious exercise, the toning effect of cool 
 spray-baths, and the right food and plenty of it, 
 will cure almost any case of tuberculosis in its 
 early stages. And the tubercle bacillus is more 
 resistant than most others of the tribe. 
 
 Pure Food and Water 
 
 Our foodstuffs furnish another obvious medium 
 through which the microbes may be conveyed 
 into our bodies. 
 
 Here it is equally obvious that attention to
 
 The Battle of the Microbes 67 
 
 cleanliness and a few common-sense precautions 
 may go a long way toward thwarting the enemy : 
 
 Avoid the grocer who does not protect his 
 wares from flies. 
 
 If the water supply is doubtful, boil all drinking 
 water; it may be aerated afterward by pouring 
 from one receptacle to another, that it may not 
 taste flat. Ice that has been stored for months 
 is usually sterile, but not always. Mere freezing 
 for a short time does not kill bacteria. 
 
 It is safer to keep the water-pitcher in the ice- 
 box than to put ice in the water. 
 
 All other questions that concern germ-infected 
 food are relatively insignificant, however, in com- 
 parison with the problem of the milk supply. In 
 the case of infants it is of course the only prob- 
 lem. Contaminated milk is the prime source of 
 infection which results in the death in infancy of 
 one-tenth of the human race. 
 
 At every third or fourth tick of the clock an 
 infant dies whose death tells of the victory of a 
 bacterial host that should never have been al- 
 lowed to find its way into the victim's digestive 
 tract. 
 
 Of course the milk supply is everywhere under 
 surveillance of health boards nowadays; but the 
 official inspectors must have the co-operation of 
 the public or their efforts are unavailing. 
 
 What most people do not understand is that all 
 milk contains bacterial germs. Even before it 
 leaves the udder of the cow, bacteria have found 
 their way to it ; others are added in the process of
 
 68 Adding Years to Your Life 
 
 milking. No health board anywhere pretends to 
 rule that milk sold with its sanction shall be germ- 
 free. That would be a condition impossible to 
 fulfil. All that is done is to limit the permissible 
 number. 
 
 But the terms of the regulations are far from 
 reassuring. The city of Boston places the limit 
 at 500,000 bacteria to the cubic centimeter (about 
 fifteen drops). Montclair, New Jersey, after a 
 crusade led by its celebrated surgeon, Dr. J. S. 
 Brown, boasts of a milk supply averaging less 
 than 100,000 germs to the cubic centimeter. In 
 New York City, " certified " milk must contain 
 no more than 30,000 germs to the cubic centimeter, 
 but Dr. Park's investigation showed that milk 
 sold in the shops averaged 300,000 bacteria per 
 cubic centimeter in the coldest weather, about 
 1,000,000 in cool weather, and 5,000,000 in hot 
 weather. 
 
 Drs. Heinemann and Jordan tested market milk 
 in Chicago, the microbe population of which 
 ranged to 74,000,000 per cubic centimeter about 
 five million in every drop! 
 
 Such is the beverage with which we feed our 
 babies. 
 
 These astounding figures call for explanation. 
 The explanation is simple : milk at ordinary tem- 
 perature is supremely good food for bacteria. 
 They fairly revel in it, multiplying inordinately. 
 So the presence of vast numbers of bacteria in 
 any given sample of milk does not necessarily 
 impugn the dairy from which the milk came. It
 
 The Battle of the Microbes 69 
 
 only proves that the milk has been kept for a con- 
 siderable time, and kept in a warm place. 
 
 We have seen something as to the fecundity of 
 bacteria. So it need not surprise us that a sample 
 of milk having 42,000 bacteria in a given quantity 
 when twenty-four hours old, showed 12,200,000 
 bacteria in the same sample three days later. But 
 we could hardly be prepared for the difference in 
 rapidity with which the same bacteria develop 
 under conditions precisely identical in regard to 
 everything but temperature. 
 
 Thus a sample of milk kept at 4 degrees centi- 
 grade had 2,500 bacteria per cubic centimeter in 
 twenty-four hours; while another sample of the 
 same milk kept at 13 degrees had developed 18,800 
 bacteria ; and a third sample at 20 degrees showed 
 45,000. Thus a difference in temperature of only 
 16 degrees multiplied the growth of the bacteria 
 by about two thousand per cent. 
 
 It would appear, then, that if the baby is to be 
 given a reasonably fair deal, it must at the very 
 least be supplied with perfectly fresh milk (which 
 is obviously impossible for the city dweller) or 
 else milk that has been kept at all times at approxi- 
 mately the temperature of ice. 
 
 A further element of safety is added if the milk, 
 in addition to being pure and fresh, has been pas- 
 teurized. This process consists merely in heating 
 the milk to a temperature of 60 degrees centigrade 
 (140 degrees Fahrenheit) for twenty minutes, and 
 then rapidly cooling it. This does not free the 
 milk absolutely from bacteria, but it does kill the
 
 70 Adding Years to Your Life 
 
 germs of typhoid fever, dysentery, diphtheria, 
 and tuberculosis, if any of these chance to be 
 present. 
 
 The death-rate in an infants' hospital has been 
 known to be reduced by fifty per cent in a single 
 year when pasteurized milk was introduced, even 
 though the milk previously used was fresh milk 
 from a selected herd pastured on the hospital 
 grounds. 
 
 In the particular hospital in question, pasteur- 
 izing the milk, without any other change in diet or 
 hygiene, is estimated to have saved the lives of 
 1,243 infants in seven years. 
 
 When the average mother learns to give her 
 baby as good a chance as the waifs received in the 
 foundling hospitals, the slaughter of the innocents 
 in the world at large will be proportionately re- 
 duced. But we can hardly expect this until the 
 time comes when the average man and woman 
 take as much interest in the battle of the microbes 
 which vitally -concerns their own lives and the 
 lives of their children as they now take in the 
 bickerings of political parties, the records of 
 scandals and murders, and the warring of Ser- 
 vians, Turks, and Bulgars.
 
 m 
 
 Messengers of Death and How to Outwit Them 
 
 THE fly that is crawling across the bread-plate 
 there on your dinner table has recently come 
 from a garbage pile, or perhaps from the putres- 
 cent carcass of a dog. The reflection is not appe- 
 tizing, but you know it to be true. There are 
 thousands of bacteria on the body and feet of the 
 fly. Among them are perhaps some germs of 
 typhoid fever or dysentery or tuberculosis. 
 
 You are quite aware of this, yet you tolerate 
 the fly, and run the needless risk of becoming its 
 victim. 
 
 Nor is the fly the only disease-carrier that in- 
 vades your household more or less through your 
 negligence or indifference. Observe, for example, 
 that your dog is scratching himself. You know 
 that he is pestered by fleas, and the thought gives 
 you no great concern. But suppose that these 
 fleas chance to have come to the dog from the 
 body of a rat that is infected with the plague. 
 Suppose, then, that one of the tiny acrobats 
 springs to the body of your child as it plays with 
 the dog. As a sequel, the child may presently de- 
 velop a mysterious and fatal illness, and the mal- 
 ady may spread till every member of your house- 
 hold is stricken. 
 
 71
 
 72 Adding Years to Your Life 
 
 " The thing is utterly impossible," you say. 
 On the contrary, it lies well within the possibili- 
 ties. 
 
 You must have read not long ago of the finding 
 of a plague-infected rat at New Orleans and an- 
 other at Philadelphia. Where one or two such 
 rats are captured, there may very well be hun- 
 dreds that escape detection. Indeed, it would be 
 absurd to suppose that the health authorities have 
 captured the only infected specimens. Nor can we 
 suppose that the two ports named are the only 
 ones at which infected rats have entered. Once 
 ashore, the rat can travel fast and far in freight 
 cars, so he may readily invade the interior of the 
 country. 
 
 And it is through the agency of the flea that the 
 virulent disease to which the rat is subject may 
 be transmitted to man. 
 
 The Plague at Our Doors 
 
 It was with reference to this disease, and to the 
 necessity of ridding the country of the rats and 
 fleas that transmit it, that the Journal of the 
 American Medical Association recently uttered 
 this warning: 
 
 " The sooner the country realizes that it is face 
 to face with a most serious problem, the better it 
 will be for the lives of the people, and also for 
 commerce." 
 
 This most authoritative organ of the medical 
 profession in America urges that the danger is
 
 Messengers of Death and How to Outwit Them 73 
 
 imminent, and that it will be greatly enhanced 
 when the opening of the Panama Canal brings 
 an influx of ships from the western coast of South 
 America to our ports. 
 
 The disease in question is known as bubonic 
 plague. It is a disease with a history. When it 
 swept across Europe in the Middle Ages, it 
 devastated entire populations and it was remem- 
 bered in aftertime as the " Black Death," or the 
 " Great Mortality." 
 
 In a single epidemic, in 1348-1349, it is esti- 
 mated to have claimed twenty-five million victims, 
 about one-fourth of the entire population of 
 Europe. 
 
 The epidemic of 1665 caused 70,000 deaths in 
 London, and drove the survivors to the open fields 
 outside the city. 
 
 All this you have doubtless heard ; but it seems 
 remote and impersonal. You know that in those 
 old days the streets of a city were filled with 
 refuse, seeming to invite disease ; and if you have 
 given the matter a thought you have assumed that 
 there could be no possible repetition of such dis- 
 astrous epidemics in our sanitary age. 
 
 Be advised, then, that recent discoveries tend 
 to disturb the composure with which hitherto most 
 people have contemplated the records of the Black 
 Death. It is now known that the disease has no 
 direct connection with filthy or unsanitary condi- 
 tions ; that its cause is a particular bacillus which 
 flourishes in the system of the common house rat, 
 and which may be transmitted from rat to rat, or
 
 74 Adding Years to Your Life 
 
 from this host to a human being, by that familiar 
 pest, the flea. 
 
 Therefore, any region where the rat is found 
 may be subject to invasion by the plague, for the 
 rat is almost never without its insect parasite. 
 So the matter comes directly home to you and to 
 me. 
 
 The false security in which we have rested has 
 been due to the fact that there has been no severe 
 epidemic of the plague in Europe for more than a 
 hundred years. 
 
 It is not quite clear why there should have been 
 such long intervals of quiescence. But there is 
 abundant evidence that an epidemic is now im- 
 pending, which, if it is not combated, might read- 
 ily rival the historic outbreaks that have made the 
 name so dreaded. About fifteen years ago the 
 disease began to spread from an infection centre 
 in China. In 1893 it appeared in Hongkong, and 
 in 1896 in Bombay. 
 
 In the ten succeeding years it caused about six 
 million deaths in India. 
 
 Then the disease began to crop out in the west- 
 ern hemisphere; first at Santoz, Brazil, in 1899; 
 then at San Francisco. 
 
 By this time the investigations of the British 
 Plague Commission in India had established the 
 manner of transmission of the disease. It was 
 shown that infected rats might transmit the dis- 
 ease from port to port, even though no human 
 passenger on the ship became infected. So war 
 was raged on the rats by the health authorities in
 
 Messengers of Death and How to Outwit Them 75 
 
 San Francisco. More than a million were killed 
 in 1907, and many were found to be infected with 
 the plague bacillus. The disease was spread, 
 through the agency of fleas, from rats to the 
 ground squirrel; and in a few cases, through the 
 same agency, to man. 
 
 The strenuous warfare on the rats prevented 
 anything like a general epidemic, however; and 
 the same vigilance at other ports in the United 
 States, as well as in Europe, Australia, and Japan, 
 has been similarly rewarded. But the plague has 
 very recently gained a foothold in Porto Rico and 
 in Cuba, where a few deaths occurred in the sum- 
 mer of 1912, leading to an immediate reinforce- 
 ment of the rat-killing squad of the Health De- 
 partment. The acuteness of the danger is now 
 emphasized by the finding of infected rats in our 
 eastern seaports. 
 
 Of course, health officers everywhere are on the 
 qm vivej and the world-wide systematic attack on 
 the rat cannot fail of some results. 
 
 Concrete wharves and buildings with cement 
 foundations are making life less easy for the ro- 
 dents. In some regions, as the Panama Canal 
 zone, houses are built on pillars of concrete, or 
 on posts with inverted metal shields at top, in 
 imitation of the familiar expedient by which farm- 
 ers protect their corn cribs against the same 
 pests. Ships in tropical ports are sometimes re- 
 quired to have rat guards on all ropes or hawsers 
 reaching ashore. 
 
 But all these measures must be supplemented
 
 76 Adding Years to Your Life 
 
 with the co-operation of householders in general if 
 the desired extermination of the rat is to be 
 effected. And until we are well rid of these pro- 
 lific little rodents we shall never be quite free from 
 danger of a world- wide visitation of the " Black 
 Death," for it is obviously impossible to eradi- 
 cate the flea except through the destruction of its 
 host. 
 
 Here, then, is a task of the utmost importance 
 in which almost everyone can lend a hand. 
 
 Mosquitoes and Malaria 
 
 " An interposition of Almighty God provoked 
 by the sins of man " is the way in which a seven- 
 teenth century writer refers to the plague. The 
 twentieth century discovery that the agent of 
 transmission is really an insignificant insect is 
 one of the important items of new knowledge 
 through which our entire conception of the spread 
 of epidemics is being revolutionized. 
 
 Of course, it has been known for some time that 
 most diseases are due to definite germs ; that you 
 can no more have consumption or typhoid fever 
 or diphtheria unless the germs of these diseases 
 are sown in your system than the farmer can raise 
 crops of wheat or corn or rye without sowing these 
 grains on his soil. 
 
 But it is only within the past few years that we 
 are beginning to get a clear notion as to the way 
 in which the transfer of germs from one human 
 being to another is carried on.
 
 Messengers of Death and How to Outwit Them 77 
 
 It is now clear that there are many kinds of 
 germs which do not float in the air, to be dissemi- 
 nated by every chance breeze, but which must be 
 carried from person to person as definitely as 
 grain is carried to the field by the farmer. 
 
 There are even germs, particularly those of ani- 
 mal nature (so-called protozoa, to be distin- 
 guished from the bacteria, which are classified in 
 the vegetable kingdom), that depend for their ex- 
 istence upon the good offices of a particular type 
 of insect, and must perish as a race if that insect 
 is not at hand. 
 
 As the best-known example, take the case of the 
 microscopic protozoal organism, called a Plasmo- 
 dium, that is the sole cause of malaria. 
 
 This pestiferous microbe leads a double life in 
 a very literal sense. At one prolonged stage of 
 its history it maintains a celibate existence, 
 lodging in the red blood-corpuscles of the human 
 body, and multiplying solely through the forma- 
 tion of spore-like divisions of its substance. The 
 setting free of a generation of spores (" merozo- 
 ites " they are called) coincides with the onset of 
 the characteristic chill that marks the disease. 
 
 The germ thus makes its human host most un- 
 comfortable, and even causes the death of many 
 thousands of individuals each year ; yet the plas- 
 modium itself does not come to its own, so to speak, 
 so long as it remains in the human system. It 
 completes its life-cycle only when sucked into the 
 stomach of a mosquito. 
 
 Nor can any and every mosquito serve the pur-
 
 78 Adding Years to Your Life 
 
 pose : it is only mosquitoes of the genus Anopheles 
 that can serve as host. 
 
 But in the system of this particular insect, the 
 plasmodium takes on a new lease and a new man- 
 ner of life, multiplying sexually, and developing 
 a generation of offspring that will lodge in the 
 salivary glands of their host, thence to be trans- 
 mitted to any human subject that the mosquito 
 chances to assail. 
 
 Such being the life history of the malaria germ, 
 it follows that by destroying this particular type 
 of mosquito we should eliminate the plasmodium 
 race and rid mankind of the widely prevalent 
 disease malaria. 
 
 You may reside if you wish on the borders of the 
 most " miasmatic " swamp; wade in or imbibe its 
 waters; breathe its air day and night and there 
 is not the remotest chance that you will be stricken 
 with malaria so long as you are guarded against 
 the attacks of the mosquitoes of the genus 
 Anopheles. Such is the accepted and demon- 
 strated fact to-day. 
 
 The ferreting out of the secret was chiefly done 
 by Dr. Ronald Ross, of the British Army in India, 
 as recently as 1897. Subsequent practical experi- 
 ments of Drs. Rignami in Rome and Manson in 
 London were required to overcome the incredulity 
 of the medical profession. 
 
 The suggestion that a mosquito may play this 
 extraordinary role had indeed been made some 
 years earlier by the American physician, Dr. A. 
 F. A. King; but proof was not then forthcoming
 
 Messengers of Death and How to Outwit Them 79 
 
 and the suggestion was ignored or openly dis- 
 credited. 
 
 Now that the facts are known, every community 
 should think it worth while to rid itself of these 
 pests, by curtailing their breeding places. You 
 can do your share by pouring kerosene on the sur- 
 face of any stagnant pool in your neighborhood. 
 You should also see that no gutters or rain bar- 
 rels or other receptacles of water are permitted to 
 remain uncovered. 
 
 Even an old tin can may offer a breeding place 
 from which myriads of malaria-carriers will come 
 forth. 
 
 The Yellow Fever Mosquito 
 
 Proof that the mosquito is the carrier of the 
 germs of malaria served to give a new aspect of 
 plausibility to a theory first put forward by Dr. 
 Nott of New Orleans as long ago as 1848, and 
 prominently advocated by Dr. Charles J. Finlay 
 of Havana in 1881, to the effect that the virulent 
 disease yellow fever is also transmitted by a mos- 
 quito. 
 
 At the time when the American authorities set 
 about renovating Havana, no one took much stock 
 in the theory, except Dr. Finlay. It seemed clear 
 enough to all other observers that yellow fever is 
 transmitted through the air, or at least through 
 the medium of clothing, bedding, and the like. 
 
 But Dr. Finlay 's insistence led to an official test 
 of his unlikely theory, under direction of a Com-
 
 8o Adding Years to Your Life 
 
 mission comprising the U. S. Army surgeons, Drs. 
 Eeed, Carroll, Agramonte, and Lazear, the last 
 named of whom, it should not be forgotten, lost 
 his life in the course of the experimental investi- 
 gation. 
 
 Many lives were hazarded. It could not be 
 otherwise, because the germ of yellow fever had 
 not been isolated, hence microscopic tests, such as 
 were used with the parasite of malaria, could not 
 be employed. It was necessary to expose human 
 beings to the conditions of infection, and await 
 results. 
 
 Volunteers from among the American soldiers 
 quartered in Cuba were not wanting. The mem- 
 bers of one group were confined in rooms contami- 
 nated with the effects of victims of yellow fever ; 
 subject to the usual supposed channels of infec- 
 tion, but rigidly guarded against the attacks of 
 mosquitoes by the careful screening of their quar- 
 ters. These men remained free from disease. 
 
 Members of another group were kept away from 
 all contaminating surroundings, but were allowed 
 to be bitten by mosquitoes that had had access to 
 yellow fever patients. Six out of seven of these 
 men promptly developed the fever. 
 
 The tests were so definite as to remove all doubt. 
 The carrier of yellow fever was found to be a mos- 
 quito of the genus Stegomyia. When this mos- 
 quito is eliminated or excluded, yellow fever dis- 
 appears. Abundant proof of this has been given 
 in Cuba, and also in the Panama Canal zone. In 
 the latter region, under the able supervision of
 
 Messengers of Death and How to Outwit Them 81 
 
 Colonel Gorgas, the draining of pools and the 
 netting of porches and windows resulted in trans- 
 forming a pest-ridden zone into a place of salu- 
 brity and health. 
 
 No such transformation, perhaps, was ever be- 
 fore or elsewhere effected in so short a time and 
 as the direct result of a new and unexpected sci- 
 entific discovery. 
 
 The Typhoid Fly 
 
 The trenchant if inelegant slogan " Swat the 
 fly! " has become so familiar that one is likely to 
 forget how recent is the discovery that the fly has 
 an important share in the transmission of disease. 
 
 It is only a few years since this possible source 
 of contagion was utterly unheeded, even by the 
 medical profession. As recently as 1898 our sol- 
 diers in the Cuban War were permitted to die by 
 hundreds of typhoid fever because no one thought 
 to take the precaution to render the dejecta of in- 
 fected persons innocuous or to put infected matter 
 beyond the reach of flies. 
 
 And so, as has been said, the common house fly 
 rather than Spanish bullets was responsible for 
 the chief mortality in our Cuban army. But the 
 like of this will not occur in any warfare of the 
 future ; for the insect has now been re-christened 
 the " typhoid fly," and everyone realizes what 
 danger may attend its visitations. 
 
 The re-christening was due, I believe, to Dr. L. 
 0. Howard, our expert Government Entomologist,
 
 82 Adding Years to Your Life 
 
 who has done more than anyone else to call public 
 attention to the history of this familiar but little 
 understood insect. The new name is highly appro- 
 priate, in that it serves to call attention to a chief 
 danger with which the insect menaces us. It 
 should be understood, however, that the fly is not 
 the host of the typhoid bacillus in the sense in 
 which the Anopheles mosquito is the host of the 
 germ of malaria. 
 
 The fly becomes an involuntary carrier of dis- 
 ease germs merely through accidental contamina- 
 tion of its feet or wings or body or buccal appa- 
 ratus. 
 
 It transfers quite impartially any germs that 
 chance to adhere to it. 
 
 Microscopic examination has shown that mil- 
 lions of bacteria may sometimes be found on the 
 body of a single fly. Ordinarily, these are of more 
 or less innocuous species. That typhoid germs are 
 sometimes among the number is merely due to the 
 filth-frequenting habits of the insect. The germs 
 of tuberculosis are also susceptible of conveyance ; 
 likewise those of diphtheria and cholera. Profes- 
 sor Nuttall has shown that the fly may not only 
 ingest the germs of bubonic plague, but may itself 
 fall victim to the disease. 
 
 The best protection against danger from the fly 
 would obviously be found in extermination of the 
 insects themselves. But this offers tremendous 
 difficulties. 
 
 A single fly that finds access to refuse heap or 
 garbage pail may deposit a complement of about
 
 Messengers of Death and How to Outwit Them 83 
 
 120 eggs that will hatch to maggots in five days, 
 and appear as adult flies in five days more. The 
 life-cycle is so short, the fecundity of the insect 
 so great, that the progeny of a single female in a 
 summer season would if unrestrained reach unbe- 
 lievable numbers. 
 
 Here are the figures, according to someone who 
 has taken the trouble to make the computation: 
 1,096,181,249,311,720,000,000,000,000. 
 
 When we reflect that (estimating 10,000 flies to 
 the quart) this would represent about 340 billion 
 bushels of flies for each man, woman, and child in 
 the United States, it would appear that the out- 
 look for a fly-catching crusade of extermination 
 is not encouraging. 
 
 And the matter seems quite disheartening when 
 the computer further assures us that if food and 
 breeding places were provided and enemies 
 evaded, the progeny of a single fly in unchecked 
 development through twelve generations may be 
 estimated as making a mass of flies measuring 
 268,778,165,861 cubic miles, or considerably more 
 than the total size of the earth. 
 
 In the light of such figures, fly " swatting," 
 though commendable enough in itself, must seem 
 an inadequate method of extermination. 
 
 But fortunately more effective measures are 
 available. A recent editorial in the Medical 
 Record, from which some of the figures just given 
 are quoted, suggests the slogan * ' No filth, no flies 
 and no disease." It urges that we follow the fly 
 to her breeding place seldom more than 300 to
 
 84 Adding Years to Your Life 
 
 500 feet away and make that place decent and 
 sanitary. We are told that we must get rid of 
 " the unsanitary closet, the manure heap, the un- 
 covered garbage can, the putrescent dead dog and 
 horse in the public highway. All refuse and de- 
 caying material and all vegetable and table waste 
 should be removed and be burned or covered with 
 lime or kerosene oil. Stable manure should be put 
 into tight pits or vaults; a barrel of chloride of 
 lime to be constantly at hand, from which each 
 deposit of manure should be sprinkled." 
 
 If every citizen would constitute himself a com- 
 mittee of one to help carry out such a reform as 
 this, we should soon abate the fly nuisance; and 
 thousands of human lives would be saved that are 
 now needlessly sacrificed. But the co-operation of 
 each and every individual is absolutely essential. 
 One family that is careless about the disposal of 
 garbage can breed more flies than an entire com- 
 munity can kill. 
 
 The very least you can do is to make sure that 
 you are not guilty of such a crime against your 
 neighbor. 
 
 Ticks and Other Creepers 
 
 It is only a few years since English text-books 
 in use in the schools seeking to carry out the old 
 delusive idea that everything must be of value to 
 man conveyed the edifying information that 
 " the fly keeps the warm air pure and wholesome 
 by its swift and zigzag flight." 
 
 I presume this antediluvian conceit is now sup-
 
 Messengers of Death and How to Outwit Them 85 
 
 pressed; but one may still hear the fly defended 
 on occasion and somewhat less farcically as a 
 scavenger. There are sundry creeping suctorial 
 insects, however, that so far as I know have never 
 found an apologist except possibly on the ground 
 of being provided to test man's temper and en- 
 durance. 
 
 Of this unwholesome company are the ticks of 
 various species. These obscure creepers are 
 known to have importance as germ-carriers, 
 largely in connection with tropical diseases of cat- 
 tle. They jeopardize the pocketbook, if not the 
 life, of the American farmer ; for the virulent cat- 
 tle disease known as Texas fever, which costs our 
 cattle-raisers many hundred thousand dollars an- 
 nually, is due to a protozoal germ that is trans- 
 mitted solely, so far as is known, by ticks. 
 
 An interesting feature of the matter is that the 
 germs are not directly transmitted from one beef 
 creature to another by any individual tick. The 
 insect, having taken its fill of blood, drops to the 
 ground, and there deposits its eggs. The young 
 that come from these eggs make their way to the 
 bodies of other cattle, and inoculate them with 
 germs acquired in this curious congenital fashion. 
 
 Thus cattle may acquire the disease by grazing 
 in an " infected " pasture, without coming in con- 
 tact with any infected animal. 
 
 To prevent the possibility of such infection, it 
 is customary before shipping cattle from the 
 " fever zone " to make them swim through a tank 
 of petroleum, which kills the ticks.
 
 86 Adding Years to Your Life 
 
 These curious facts have double interest because 
 they were first demonstrated by two American in- 
 vestigators, Drs. Smith and Kilborne, who thereby 
 proved for the first time that a protozoal disease 
 may be transmitted by a blood-sucking insect. A 
 new era in medicine dates from that discovery, 
 made in 1898. 
 
 An early result of the new knowledge was to 
 cast suspicion on the familiar wood-tick as a pos- 
 sible carrier of disease. It was suggested by Drs. 
 Wilson and Chowning, and demonstrated pres- 
 ently by Dr. H. T. Rickets, that the wood-tick is 
 the carrier of the very fatal malady known as 
 Rocky Mountain spotted fever. 
 
 In Montana this disease is much dreaded, inas- 
 much as it causes the death of about seventy per 
 cent of the persons who become infected. 
 
 Our knowledge of the disease is largely due to 
 the investigations of medical officers of the U. S. 
 Public Health and Marine Hospital Service. One 
 of these, Dr. T. B. McClintic, himself fell victim 
 to the disease, adding his name to the already long 
 list of martyrs in the cause of science. 
 
 The newspaper reports of Dr. McClintic 's death 
 (which occurred August 13, 1912), and of the 
 Congressional bill for the relief of his widow in- 
 troduced by Senator Myers, of Montana, gave the 
 general public its first knowledge of Rocky Moun- 
 tain fever, which has hitherto been prevalent 
 chiefly in Montana, Idaho, and Nevada. It should 
 be understood, however, that there seems no rea- 
 son why the disease should not invade any region
 
 Messengers of Death and How to Outwit Them 87 
 
 of the country to which infected ticks chanced to 
 be conveyed; so the effort to eliminate the ticks, 
 in which Dr. McClintic lost his life, is an enter- 
 prise having first-hand interest for all of us. 
 
 The Fly that Carries Sleeping Sickness 
 
 Very recently Dr. G. H. F. Nuttall, the Ameri- 
 can Professor of Biology at Cambridge Univer- 
 sity, has made an exhaustive study of the entire 
 tribe of ticks, with reference to their germ-carry- 
 ing habits. 
 
 He finds that the insects play an all-important 
 role in the spread of various allied protozoal ani- 
 mal diseases of the Tropics. 
 
 In at least one case a protozoal germ closely 
 similar to those that cause the cattle fevers may 
 flourish in the blood of man, causing the deadly 
 malady known as ' ' sleeping sickness. ' ' The agent 
 of transmission here, however, is not a tick but a 
 small winged insect called the tsetse fly. Unlike 
 the typhoid fly, this insect bites through the skin 
 and sucks the blood, and thus may transfer the 
 germ of sleeping sickness (called a Trypanosome) 
 from one human subject to another. 
 
 Sleeping sickness is confined to the tropical re- 
 gions of Africa, presumably because of the tsetse 
 fly's restricted habitat; but it is so prevalent and 
 virulent a plague that entire regions are some- 
 times depopulated owing to its ravages. 
 
 The disease has spread over new areas in recent 
 years. It is estimated to have caused in the neigh-
 
 88 Adding Years to Your Life 
 
 borhood of half a million deaths among the natives 
 of the Congo region in the decade 1896-1905. In 
 some regions of Senegambia, from 30 to 50 per 
 cent, of the population of a village are found to be 
 infected; and infection in this case means sure 
 death. 
 
 Persistent efforts have been made, particularly 
 by Professor Ehrlich, to find a remedy that will 
 cure sleeping sickness, but with doubtful success. 
 To be bitten by an infected tsetse fly is to receive 
 a death sentence that cannot be evaded. Even 
 should a remedy be found that will cure the dis- 
 ease, this would obviously be only a tentative 
 measure. 
 
 Nothing short of the extermination of the tsetse 
 fly itself can make civilization possible in the re- 
 gions it now frequents. 
 
 The undoubted fact that progress is thus held 
 in check by a tiny insect may be pondered in con- 
 nection with Dr. Ross's suggestion that the de- 
 cadence of civilization in ancient Greece may have 
 been due to the encroachments of the malaria- 
 transmitting mosquito. 
 
 Who until very recently suspected such influ- 
 ences as these in history? Who would have dared 
 suggest that the proboscis of a tiny insect may be 
 mightier than sword or pen? Yet the validity of 
 such a claim becomes increasingly evident as we 
 study the recent discoveries in relation to the 
 transmission of disease. In the light of what is 
 now known, it is not too much to assert that insects 
 of two or three species have undoubtedly been re-
 
 Messengers of Death and How to Outwit Them 89 
 
 sponsible for more human deaths in modern Eu- 
 rope than all the implements of warfare that man 
 has devised. 
 
 As to venomous serpents and savage beasts, 
 their entire toll of human lives since history be- 
 gan is a negligible quantity in comparison. 
 
 The Ubiquitous Bedbug 
 
 It is not unlikely that the worst offender of all 
 is an insect that until very recently has scarcely 
 been under suspicion. I refer to that most un- 
 popular of creeping things, an object of abhor- 
 rence to every conscientious housewife, which the 
 squeemish writer commonly refers to as Cimex 
 lectularius, but which may best be unmasked un- 
 der its plain every-day name of bedbug. 
 
 The case against this familiar if unwelcome co- 
 resident with man is convincing and utterly con- 
 demnatory. It has been shown by Dr. Patton, of 
 the Indian Medical Service, that the fatal tropical 
 disease known as " kala-azar " may be transmit- 
 ted by the bite of the bedbug; and the Russian 
 investigator, Dr. D. T. Verjbitski, has demon- 
 strated conclusively that this insect may transmit 
 the germs of the bubonic plague quite as effec- 
 tively as does the flea. 
 
 Not only may the insect transmit the germs di- 
 rectly in biting; but on linen soiled by the insects 
 or contaminated by their crushed bodies the 
 plague germs may retain life and virulence for a 
 term of at least five months.
 
 go Adding Years to Your Life 
 
 Of this discovery, Dr. J. V. Manning, writing 
 recently in the Medical Record, says that to the 
 student of preventive medicine " Verjbitski's 
 demonstration that bedbugs transmit blood-borne 
 diseases is the most revolutionary discovery made 
 since Pasteur announced the etiology of anthrax. 
 This illuminating thesis lightens the path along 
 which science has floundered in search of the com- 
 mon mode of transmission of acute epidemic dis- 
 ease. It would appear that any disease whose 
 germ or virus is liberated in the blood at any stage 
 of the attack may be transmitted by the ubiquitous 
 bedbug." 
 
 Among the common disease specifically named 
 as probably transmissible by this insect are infan- 
 tile paralysis, measles, smallpox, and scarlet 
 fever. A complete list would probably include, as 
 Dr. Manning suggests, practically every infectious 
 blood disease. 
 
 Bearing this in mind, and considering the habits 
 of the bedbug, it seems not unlikely that this insect 
 may be the most important of all agencies for the 
 spread of epidemic diseases, particularly in the 
 tenement regions of cities. Hiding in the cracks 
 and crevices, and passing from one apartment to 
 another, the insects may very well be supposed to 
 carry the germs of infection as of infantile 
 paralysis or measles or diphtheria from one fam- 
 ily to another throughout a crowded block. 
 
 Nor must we overlook the extent to which the 
 insect may effect involuntary migrations from 
 one social stratum to another.
 
 Messengers of Death and How to Outwit Them 91 
 
 Unwelcome as the thought may be, it is true that 
 there is a constant distribution, and that the insect 
 may gain access to the best-regulated household 
 in spite of every reasonable precaution, as a recent 
 Bulletin of the U. S. Entomological Bureau has 
 declared. 
 
 Says Dr. Manning: " The physician returns 
 from the slum case and the lawyer from the court 
 where bedbugs swarm; the maid takes her half- 
 day in a tenement home, the daily paper is dis- 
 tributed by a tenement dweller, the hand laundry 
 often returns from a tenement district; the vaca- 
 tion is spent in unfumigated summer camps, and 
 the traveler's bag or trunk is a usual hiding-place 
 for Cimex ; men, women, and children of all social 
 classes come in close contact in railroad stations, 
 transit lines, theatres, schools, moving picture en- 
 tertainments, summer amusements, and public 
 inns." 
 
 Hence the possible invasion of every home by 
 the " retiring but ubiquitous bedbug." 
 
 All of which makes very unpleasant reading, but 
 is pre-eminently important because it brings to 
 mind a vivid picture of dangers to which everyone 
 is more or less subject, but which until very re- 
 cently no one had suspected. 
 
 Of course, the remedy suggests itself: the bed- 
 bug must be eliminated, just as the mosquito, the 
 fly, and the flea-laden rat must be eliminated, in the 
 interests of public health. 
 
 But how is the feat to be accomplished? 
 
 Undoubtedly the task presents difficulties of no
 
 ga Adding Years to Your Life 
 
 common order. Tentative measures are familiar 
 to every housewife. But efforts of a more com- 
 prehensive character are necessary ; and the mat- 
 ter is so important that the U. S. Bureau of Ento- 
 mology has recently issued a Bulletin telling in 
 detail how to fumigate a house with hydrocyanic 
 acid gas, which will penetrate to the remotest 
 crevices and destroy every living thing. Measures 
 so heroic are obviously for the use of Health Offi- 
 cers, not for private individuals ; but a full recog- 
 nition of the dangers to which Cimex lectularius 
 subjects us will lead citizens in general to co- 
 operate with the authorities in exterminating this 
 deadly pest.
 
 IV 
 
 Is Your Brain All Right? 
 
 T long ago a novel attraction held the atten- 
 tion for an entire week of thousands of 
 visitors at the College of the City of New York. 
 It was called the Mental Hygiene Conference and 
 Exhibit. Nothing like it had ever previously been 
 seen anywhere in the world. It had to do with a 
 subject that most people have never given a 
 thought, yet a subject of paramount importance 
 to all of us the question of conserving mental 
 health and efficiency ; your mental health and mine, 
 and the mental health of our children. 
 
 It is safe to say that a majority of the thousands 
 who visited the exhibition learned more in a half 
 hour about the brain and mind; about mental 
 health and mental aberration; about ministering 
 to the mind diseased and training the normal 
 mind, than they had ever known before. 
 
 As Dr. Stewart Paton, of Princeton, who pre- 
 pared the main exhibit, has said, the display 
 seemed to bring home to many observers with the 
 force of a new discovery the fact that human be- 
 ings have brains. 
 
 That was a timely revelation. We have all 
 learned a great deal in recent years about the care 
 of the body; about the prevention and cure of 
 
 93
 
 94 Adding Years to Your Life 
 
 physical diseases. It is time, then, that we should 
 be made to realize that even the most robust phys- 
 ical health is not worth having unless mental 
 health which is equivalent to health of brain 
 goes with it. 
 
 The novel exhibit which emphasized this lesson 
 by mechanism and picture and diagram was pre- 
 pared under the auspices of a remarkable organi- 
 zation called the National Committee for Mental 
 Hygiene. The conference feature, involving the 
 discussion of a wide range of cognate topics by 
 distinguished authorities, owed its success in large 
 measure to the efforts of Mr. Everett S. Elwood, 
 executive secretary of the Committee on Mental 
 Hygiene of the State Charities Aid Association of 
 New York. 
 
 The movement thus inaugurated is part of a 
 general campaign of the National Committee for 
 Mental Hygiene, designed, in the words of the 
 president of the organization, Dr. Lewellys F. 
 Barker, of Johns Hopkins, *' to secure human 
 brains so naturally endowed and so nurtured that 
 people will think better, feel better, and act better 
 than they do now." The Committee having this 
 ambitious aim has a membership that includes col- 
 lege and university presidents, from Massachu- 
 setts to California, noted clergymen, Protestant 
 and Catholic; distinguished medical specialists, 
 superintendents of hospitals for the insane, and 
 a number of well-known business men and social 
 reformers. 
 
 Notwithstanding its distinguished personnel,
 
 Is Your Brain All Right? 95 
 
 however, perhaps nothing else about the organiza- 
 tion is more remarkable than the story of its 
 origin. 
 
 The Origin of the Movement 
 
 The National Committee, which has so soon at- 
 tained national standing and importance, is the 
 direct outgrowth of the efforts of a single indi- 
 vidual. Its founder is Mr. Clifford W. Beers, a 
 Yale graduate who had the misfortune while still 
 a young man to suffer a prolonged mental illness 
 that led to his confinement for a period of more 
 than three years in hospitals for the insane. His 
 varied experiences there of which he retains a 
 very vivid and detailed recollection led him, af- 
 ter his recovery and restoration to normal society, 
 to take up a crusade for the betterment of asylum 
 management, and in particular for the prevention 
 of insanity. 
 
 So clearly and cogently did he relate his experi- 
 ences, and so sanely did he suggest remedies, that 
 he was able to gain the attention of such men as 
 the late Professor William James and the Hon. 
 Joseph Choate, who urged him to write out his 
 story. He did so; the result being published as 
 a book under title of A Mind That Found Itself. 
 
 Professor James pronounced the book " irre- 
 proachable in style, in temper, and in good taste; 
 fit to remain in literature as a classic account 
 ' from within ' of an insane person's psychology; 
 a narrative of absorbing interest which reads 
 like fiction but is not fiction. ' '
 
 g6 Adding Years to Your Life 
 
 Professor Thomas K. Lounsbury, who also read 
 the manuscript, characterized it as a well-told 
 human document having interest " far exceeding 
 that of any novel that I have read in a long, long 
 time." 
 
 President Schurman, of Cornell, described it as 
 a wonderful volume, showing literary gifts which, 
 curiously enough, might never have come to light 
 but for the author's almost tragic experiences. 
 " A hospital for the insane," he declared, " is the 
 last place in the world one would have selected as 
 a school of liberal culture, yet in Mr. Beers' case 
 it meant a good deal more for literary develop- 
 ment than a college does for the generality of 
 students." 
 
 Such a narrative naturally brought the story 
 and the ideas that grew out of it to the attention 
 of a wide public. Expressions of sympathy and 
 approval from the most varied quarters sustained 
 Mr. Beers in the determination to put his plans for 
 the betterment of the insane, and in particular for 
 the prevention of insanity, into practical opera- 
 tion. He sought and received the co-operation of 
 leading publicists, and the National Committee 
 for Mental Hygiene came into being. 
 
 The new organization, despite its distinguished 
 personnel, started out in the most modest way 
 imaginable. It had no funds, no abiding place, no 
 set programme only enthusiasm and an idea. 
 But in due course a philanthropic gentleman, who 
 desires for the present to be nameless, placed 
 fifty thousand dollars at its disposal, enabling it
 
 Is Your Brain All Right? 97 
 
 to acquire a local habitation and take on more 
 aggressive activities. 
 
 With Dr. Thomas W. Salmon as director of 
 special studies, and under the .secretaryship of 
 Mr. Beers himself, active work is now in progress 
 at the New York headquarters of the Committee. 
 
 Thus the movement which had its inception in 
 the mental sufferings of a patient in the wards of 
 a hospital for the insane has been fairly launched 
 on a nation-wide campaign that promises to be of 
 the utmost benefit, not only to the insane, but to 
 our race as a whole ; by " arousing the public con- 
 science " in regard to insane dependents, as Pro- 
 fessor James put it ; by enabling many a wavering 
 mind to " find itself," and by pointing the way to 
 higher standards of mental efficiency for all of us. 
 
 The Need of Better Brains 
 
 Dr. Barker names as first among the objects of 
 the organization, " the protection of the mental 
 health of the public at large." 
 
 Probably it has never occurred to most of us 
 that our mental health is in need of protection; 
 but that is largely because we are mostly oblivi- 
 ous to a matter that concerns us more vitally than 
 any other. 
 
 If we gave the subject attention, a good many 
 of us would discover that some rules for mental 
 hygiene might not be amiss for us. 
 
 How many of us, for instance, are entitled to 
 feel that our mental efficiency is fully at par? The
 
 98 Adding Years to Your Life 
 
 generality of us, if quite candid with ourselves, 
 must admit that our memories are not as precise 
 and retentive in their records as we could wish; 
 that our capacity for concentration leaves a good 
 deal to be desired ; and that our powers of will are 
 more or less vacillating and on the whole in- 
 effective. 
 
 A good many of us have habits of thought that 
 are positively slovenly. 
 
 We slur over what we read in such fashion that 
 we have no precise and really usuable knowledge 
 of it overlooking essential names, forgetting im- 
 portant dates, remembering the facts of an argu- 
 ment only vaguely and doubtfully. 
 
 You pore over your morning paper at the break- 
 fast table, reading of a war in the near East, of a 
 scientific discovery in Germany, of the findings of 
 a Congressional investigation committee, and the 
 like. You are interested and wish to remember 
 what you read. But suppose you were called on 
 at the dinner table to give a clear resume of the 
 morning's news, noting essentials and omitting 
 the non-essentials ; stating names and dates ; giv- 
 ing a clear, logical consecutive account of what is 
 important. Could you perform the task in a man- 
 ner to satisfy yourself or your hearers? If not, 
 your brain is not the well-trained, dependable ap- 
 paratus of mind that it should be. 
 
 Apply the same test to the interesting lecture 
 you heard only last night, or to the book you read 
 last week, and you get the same result. Of all that 
 you read or listened to with so much interest, only
 
 Is Your Brain All Right? 99 
 
 a hazy shadow remains as a part of your mental 
 equipment. 
 
 Similarly in the course of the business opera- 
 tions, trifling or important, that enter into your 
 work. You are forever suffering from tricks of 
 memory, faulty decisions of judgment, vacilla- 
 tions of will, and false inferences from perfectly 
 clear data. 
 
 You forget to mail your wife's letter; fail to 
 do the promised errand; overlook an appoint- 
 ment ; fritter away your time at your desk. 
 
 Your mind becomes vague and fatigued after 
 an amount of work that should have served merely 
 as a stimulus. You allow your attention to be 
 distracted by incidental noises. 
 
 You are worried over trifles, bemoan mistakes 
 that are beyond repair; give way to bursts of 
 temper that are more mind racking than any 
 amount of legitimate work; and finally end the 
 day with a feeling that you have not really ac- 
 complished half that you set out to do. 
 
 All of which shows that your brain is not the 
 well-geared, well-ordered, trained and disciplined 
 mechanism that it might be. 
 
 And this is so, largely because it has never oc- 
 curred to you that mental efficiency is in the last 
 analysis the foundation of all efficiency; that 
 mental hygiene and mind training are vastly 
 more important than physical hygiene and bodily 
 training. 
 
 More than likely you supplement these sins of 
 omission with habits that directly tend to vitiate
 
 ioo Adding Years to Your Life 
 
 the power or the quality of your mental actions. 
 You smoke far more than is good for your mind 
 and body, charging your system with the nerve- 
 poison nicotine ; or you steadily impair your brain 
 power and subject yourself to the danger of per- 
 manent mental deterioration by habitually taking 
 alcoholic beverages. 
 
 You know, probably, that tobacco is injurious 
 to you; yet you cannot forego the gratification of 
 your senses even for the sake of attaining clear- 
 ness of mind. 
 
 You have probably been told that scientific tests 
 have proved that alcohol, even in small quanti- 
 ties, a bottle of beer, a glass of wine, a cocktail 
 or highball, definitely and measurably decreases 
 the amount and quality of mental action. Your 
 observation tells you that a drink of liquor tends 
 to flush your face and momentarily to exhilarate 
 your mind. You might correctly infer that your 
 brain is similarly flushed and that the abnormal 
 activity excited must result in quick reaction. 
 Thousands of observations prove that such ex- 
 citation, due to alcohol, if persistently repeated, 
 may result in hardening of the arteries, with the 
 attending liability to rupture or the formation of 
 clots, to be followed by the degeneration of the 
 brain tissues. 
 
 Yet you prefer to take this chance rather than 
 deny yourself the transient and illusory sense of 
 well-being that a drink of liquor gives you. 
 
 If you chance to inherit some measure of neu- 
 rotic taint (and few families are totally free
 
 Is Your Brain All Right? 101 
 
 from it), or if you are subjected to some undue 
 strain from business worries or an acute illness, 
 the incipient weakening of your brain tissues 
 from the habitual use of alcohol even in small 
 quantities will supply precisely the conditions 
 best suited to put you in danger of complete men- 
 tal breakdown. 
 
 Such, indeed, is the history of at least one in 
 four among all the unfortunates who suffer 
 mental overthrow, and are taken to hospitals for 
 the insane. But even short of this, there is the 
 persistent lessening of your mental efficiency 
 which must enter largely into the question of your 
 success or failure in your life work. 
 
 All of which suggests that the task of " pro- 
 tecting the mental health of the public at large " 
 is an undertaking that need not languish for want 
 of objects of attention. 
 
 From Madhouse to Hospital 
 
 Of course you feel very confident that however 
 much your brain may lack of full efficiency or 
 action, there is no probability that it could alto- 
 gether fail you. 
 
 You may be right; yet it is worth your while 
 to recall that there are 200,000 individuals con- 
 fined in institutions for the insane in the United 
 States to-day, who a few years ago, felt about 
 themselves precisely as you feel about yourself 
 now. Certainly 50,000, perhaps 75,000, of these 
 unfortunates, owe their mental illness wholly or
 
 102 Adding Years to Your Life 
 
 in part to habits of alcoholic indulgences that at 
 one time were doubtless thought by them to be as 
 harmless as your use of alcohol " in moderation " 
 seems to you now. 
 
 Causes aside, however, the ever increasing com- 
 pany of insane dependents may well excite 
 solicitude, and questions of ameliorating their 
 conditions have strong appeal. 
 
 Even if no question of humanitarianism were 
 involved, the taxpayer cannot overlook the fact 
 that the monetary cost of the care of such insane 
 as are public charges, added to the loss through 
 their removal from the ranks of productive work- 
 ers, has been computed at not less than 
 $164,000,000 annually. 
 
 The needs of the asylum population vary with 
 different regions. In more advanced communi- 
 ties what perhaps is most needed is the enlighten- 
 ment of the public as to the excellent conditions 
 that prevail in the institutions for the insane. As 
 to these, there has been a great change for the 
 better within recent decades. Indeed, throughout 
 the past century there has been an unceasing 
 movement in the right direction. Only a little 
 over a century has elapsed since the very first re- 
 forms of Benjamin Kush in America, of Pinel in 
 France, and of Tuke in England, emancipated the 
 " lunatic " from chains and dungeons. 
 
 The present-day " hospital for the insane " is 
 an utterly metamorphosed institution, as con- 
 trasted with the " lunatic asylum " or " mad- 
 house " of even fifty years ago.
 
 Is Your Brain All Right? 103 
 
 The visitor to the modern hospital for the in- 
 sane will see no padded cells, no patients in 
 manacles, no strait-jackets even. At worst there 
 may be found an occasional patient, suffering 
 from an extreme form of maniacal exaltation, 
 whose perverted activities are restrained by the 
 firm but kindly hands of attendants, or who is 
 subjected to the soothing influence of a prolonged 
 bath. 
 
 For the rest, the major part of the patients will 
 be found occupying themselves in a manner not 
 dissimilar to the activities of normal life. 
 
 Some are at work, some at play; others are 
 reading or conversing. In the quieter or con- 
 valescent wards, the general aspect of things will 
 be that of a hotel or drawing-room rather than of 
 the traditional institution for the insane. And 
 there are sure to be many patients there whose 
 mental infirmity has not deprived them of the 
 ability to converse on a wide variety of topics 
 with entire sanity, with full intelligence, and even 
 with brilliancy. For the mind diseased is a far 
 more subtle mechanism than the average layman 
 supposes, and its derangements are not always 
 paraded with such obviousness that the casual 
 inspector may observe them. 
 
 But there are many communities in the United 
 States where utterly different conditions prevail. 
 Only a few years ago reformers in Maryland 
 found that in many regions the insane, in charge 
 of local commissioners, were secluded in cells, and 
 even manacled, quite after the method of the
 
 104 Adding Years to Your Life 
 
 traditional and actual madhouse of medieval 
 times. 
 
 In some places the sexes were permitted to as- 
 sociate indiscriminately, and the birth of illegiti- 
 mate children with a double heritage of mental 
 weakness was not unusual. 
 
 But the reform movement progressed; and in 
 due course the sick in mind, who are often robust 
 in body, were liberated from the local madhouses, 
 and permitted to come out into the sunlight and 
 carry on healthful activities. Men who had long 
 been shackled are now at work in the fields. They 
 have even assisted actively in the building of in- 
 stitutions in which such of them as are incurable 
 will be housed and cared for according to humane 
 and modern methods. 
 
 Dr. Thomas W. Salmon, director of special 
 studies of the National Committee for Mental 
 Hygiene, asserts that there are no fewer than 
 fourteen States in which care of the insane in 
 county almshouses is still permitted. 
 
 " Whereas the care of the insane in a few en- 
 lightened States is a matter of just pride," he 
 says, " there is not a single condition which ex- 
 isted in the early period of neglect and abuse 
 which does not exist to-day in some American 
 communities." 
 
 I would suggest that each reader of these lines 
 appoint himself a committee of one to ascertain 
 whether the community in which he lives is of the 
 eighteenth century or of the twentieth in its treat- 
 ment of the insane.
 
 Is Your Brain All. Right? 105 
 
 If the victims of mental disease in your com- 
 munity still go uncared for in jails and poorhouses 
 you can do no more humane and useful work than 
 to promulgate a reform movement along the lines 
 of those that have been carried out in the more 
 civilized communities of our country. 
 
 First Aid to the Mentally Wavering 
 
 But, as already intimated, the problems of 
 mental hygiene are only secondarily concerned 
 with the insane. 
 
 The watchword here as elsewhere in the modern 
 world is prevention. 
 
 The ideal is, not merely to provide proper treat- 
 ment for the individual after mental breakdown, 
 but to show the individual how to obviate break- 
 down. The world is full of persons of unstable 
 mentality who would gladly consider advice as to 
 the correction of their abnormal tendencies, did 
 they but know where to seek it. 
 
 One very practical way of getting at these bor- 
 derland cases is through the establishment of 
 psychiatric clinics, such as that recently opened in 
 Baltimore in connection with the Johns Hopkins 
 Hospital. This clinic, with its fine building just 
 under construction, was endowed by Mr. Henry 
 Phipps, who was led to take an interest in the 
 matter through the suggestions of Dr. William 
 Welsh. 
 
 The idea was perhaps gained in part from the 
 principal existing European clinics of like aim,
 
 io6 Adding Years to Your Life 
 
 which had their original inception in the fertile 
 mind of the Swiss alienist, Dr. Greisinger; the 
 best-known existing institution being that in 
 charge of Professor Kraepelin of Munich. But 
 Professor Welsh is authority for the statement 
 that Mr. Phipps was to some extent influenced 
 by reading Mr. Beers' story of his institution 
 experiences. 
 
 The Henry Phipps Clinic is in charge of Dr, 
 Adolf Meyer. Its good work is already under 
 way, and its foundation may well be regarded 
 as marking a new era in the history of the treat- 
 ment of mental disease the era of prevention. 
 
 Other new institutions having the same aim are 
 the Psychopathic Hospital at Ann Arbor, allied 
 with the State University, the Boston Psycho- 
 pathic Hospital, and the Psychiatric Clinic at 
 Bellevue Hospital in New York. 
 
 Persons who feel that their mental efficiency is 
 below par may here seek expert advice, and be 
 put on the track of mental methods that make for 
 normality and tend to ward off mental disease. 
 
 It is believed that in the immediate future 
 psychiatric clinics on the lines of these new insti- 
 tutions will be found in connection with every 
 important medical school and hospital and dis- 
 pensary throughout the country, and that local 
 societies, co-operating with the National Com- 
 mittee for Mental Hygiene, will be established in 
 every community. 
 
 In three States, Connecticut, Illinois, and Mas- 
 sachusetts, such affiliating societies are already in
 
 Is Your Brain All Right? 107 
 
 operation, and in New York the same work is 
 being carried on by the Committee on Mental 
 Hygiene of the State Charities Aid Association. 
 These societies stand ready to give free verbal or 
 written advice to all who desire information re- 
 garding the principles of mental hygiene, and the 
 avoidable causes of mental disorder. In particu- 
 lar they extend a helping hand to individuals who 
 fear nervous or mental collapse. 
 
 They do not usurp the functions of the physi- 
 cian, but they co-operate with him; often they 
 induce the patient to seek medical advice when 
 he would not otherwise do so. 
 
 If there is as yet neither psychiatric clinic nor 
 local mental hygiene society in your community, 
 you may apply, with full confidence, to the Secre- 
 tary of the National Committee for Mental 
 Hygiene, 50 Union Square, New York, for advice 
 along the lines in question, or for helpful litera- 
 ture. 
 
 Of the far-reaching educational influence of 
 these movements there can be no question. In 
 the course of the coming decade or two we may 
 hope to see the spread of popular information 
 regarding mental hygiene duplicate in some 
 measure the recent progress of knowledge of 
 hygiene of the body. The general public has been 
 given a clear notion regarding the proper physical 
 care of infants and children, and it has been taught 
 the vital need of physical exercise for persons of 
 all ages. This lesson learned, it is time to turn 
 attention to the brain.
 
 io8 Adding Years to Your Life 
 
 Mental Hygiene 
 
 It is desirable to keep your muscular system in 
 good order strong and resilient. But this is 
 not absolutely essential, except for the profes- 
 sional athlete. 
 
 Your muscles may be too weak to lift a trunk, 
 but you can hire a porter to lift it. 
 
 But on the other hand, suppose your brain is 
 not so developed as to work with maximum ef- 
 ficiency. What then? Your mind is below par 
 in some or in all of its operations. 
 
 And now it is no longer a question of hiring 
 someone to do the work that you cannot do. Weak 
 brains do not hire assistance; they put their 
 possessor in the class of the hired and the wage 
 is small. 
 
 The essential difference between the bank presi- 
 dent and the man that tends his furnace is a dif- 
 ference of only a few ounces of brain substance. 
 But these few ounces are of inestimable value. 
 
 Good brain substance is about the only thing in 
 the world that is never a drug on the market. 
 
 When we think of the matter in this light, it 
 seems rather strange, does it not, that there are 
 hundreds of thousands of men giving heed to 
 keeping their muscles developed taking home 
 exercise, going to gymnasiums, playing golf and 
 tennis where one individual gives definite 
 thought to the specific development of brain 
 power? 
 
 In so saying, I would not ignore the fact that
 
 Is Your Brain All Right? 109 
 
 health of muscle is helpful to the brain. But. 
 physical health can do no more than prepare the 
 soil, so to speak, for mental action. The free 
 circulation of healthy blood gives the brain 
 physical materials for action; but a man might be 
 a champion athlete and yet be a child in knowl- 
 edge. Mental hygiene includes physical training, 
 but it goes beyond. After the brain is made 
 physically healthy, it must be trained as the organ 
 of observation, thinking, and acting. 
 
 As you test your muscles from time to time, 
 you might well also apply some definite tests as 
 to your memory, your capacity for concentrated 
 thought, and your will power. 
 
 When men are sought to fill high positions, the 
 questions asked do not concern the golf score or 
 the size of biceps. They concern the capacities 
 of brain and of mind. Darwin and Spencer were 
 frail, sickly men. The work of their bodies would 
 have gained them scant livelihood. Their brains 
 transformed the entire intellectual viewpoint of 
 Christendom. 
 
 Brain and Mind 
 
 Of course everyone vaguely knows that all men- 
 tality depends upon the action of the brain. Yet 
 the fact is often slurred over or ignored. So it 
 cannot be amiss to emphasize the relation in 
 specific terms. 
 
 " Mind " and " brain " are not synonyms of 
 course ; but one depends absolutely upon the other. 
 
 No one competent to judge doubts that every
 
 no Adding Years to Your Life 
 
 mental action has a physical substratum in the 
 brain; and that every perverted mental action is 
 evidence of a perversion, however intangible, of 
 the brain substance. So the physical welfare of 
 the brain is directly concerned in all questions of 
 mental hygiene. 
 
 Moreover and this is the most important fact 
 of the entire subject abnormalities of the brain, 
 when fully developed, may be quite beyond re- 
 pair although it might have been perfectly feasible 
 to prevent their development. The essential 
 structures of the organ of thought include 
 myriads of specialized cells of exquisite delicacy. 
 Under the microscope they appear like tiny arrow- 
 heads, sharply outlined, with infinitesimal fibrillar 
 appendages that convey messages from one cell to 
 another. 
 
 Each cell might be likened to a storage battery, 
 and the connecting fibrils to the wires of an elec- 
 tric system. 
 
 The brain operates effectively only while both 
 cells and connecting wires are in good order. 
 
 Eamifying everywhere among the cells are the 
 all-essential blood vessels. In order that the 
 brain cells should functionate at all, they must 
 be supplied with oxygen-carrying blood. Any 
 alteration in the blood supply makes a vital attack 
 upon the brain. You may produce unconscious- 
 ness almost instantly by pressing on the arteries 
 in the neck. Any vitiation of the blood-stream is 
 felt by the sensitive cerebral tissues more quickly 
 and more vitally than by any other tissues,
 
 Is Your Brain All Right? in 
 
 Hence it is that a drug like alcohol, which may 
 disturb the normal condition of the circulation, 
 makes its influence felt immediately, and persist- 
 ently on the brain. 
 
 Not only does alcohol change the quantity of 
 blood that circulates among the thought-produc- 
 ing cells, but it vitiates the quality of the blood 
 and reduces the capacity of the brain cells to take 
 up oxygen, upon the presence of which their power 
 absolutely depends. 
 
 Stated otherwise, alcohol is a protoplasmic 
 poison. Even in very small quantities it produces 
 a measurable effect upon the activities of the 
 sensitive brain tissues; an effect that may be 
 tested in the laboratory and that has been demon- 
 strated to continue for a term of hours even when 
 a very small quantity of alcohol was taken, and 
 for several days when a larger quantity is in- 
 volved. 
 
 How Alcohol Mars the Brain 
 
 Not only so but the devitalizing effect produces 
 changes in the protoplasm that are cumulative. 
 
 The brain cells subject to this abnormal strain 
 gradually alter in their essential constituents and 
 if the strain is long continued may become per- 
 manently damaged. If tangible demonstration of 
 this were sought, it is furnished beyond all equivo- 
 cation by the fact that alcohol is a recognized 
 potent contributing factor in the causation of from 
 one-fourth to one-third of all cases of insanity, 
 the world over.
 
 ii2 Adding Years to Your Life 
 
 If this unequivocal fact could be made known 
 to every young man who is gradually acquiring a 
 taste for the regular use of alcoholic beverages, 
 the effect on the mental efficiency of our race 
 would be enormous. Dr. G. Sims Woodhead, of 
 Cambridge University, England, describes the 
 changes that accompany acute alcoholism, which 
 include " marked degenerative changes in the 
 inner lining of the small vessels of the brain, and 
 an exaggerated condition of waste a ' clogging ' 
 due to the accumulation of rapidly produced waste 
 products in the lymph spaces in the outer walls 
 of the vessels. 
 
 " It has been noted also," says Dr. Woodhead, 
 " that in some cases small clots are found in the 
 vessels clots which interfere with the transmis- 
 sion of the blood along the normal channels. This 
 clogging of the vessels and the spaces around 
 them affords evidence that the tissues are break- 
 ing down very rapidly, but its chief importance 
 appears to lie in the fact that it leads to continued 
 interference with the nutrition of the surrounding 
 tissues, thus playing a part in the determination 
 of further degenerative changes." 
 
 These changes are of an alarming character. 
 They include degeneration not only of the nerve 
 cells themselves, which may become atrophied and 
 fatty, but also in the fibrils that run out from 
 the cells. 
 
 Even where the body of the cell remains intact, 
 the fibrillar twigs may undergo remarkable 
 changes.
 
 Is Your Brain All Right? 113 
 
 " Little swellings make their appearance at 
 regular intervals, first near the tip of a process, 
 and gradually work their way back toward the 
 body of the cell, so that after a time the process 
 looks almost like a string of beads. Alongside 
 these changes, some of the lateral twigs have be- 
 come swollen and shortened, whilst others disap- 
 pear; in advanced stages the bulk of them so 
 disappearing." 
 
 This stunting and disappearance of the lateral 
 twigs of the nerve fibrils, Dr. Woodhead tells us, 
 is equivalent to severing the connecting wires of 
 an electric system, and the communications be- 
 tween cell and cell are done away with. 
 
 Ultimately it may come to pass that " so many 
 of the connecting wires are cut out, as it were, and 
 the interference with the passage of nerve im- 
 pulses along the nerves is so marked, that com- 
 mencing with the more delicate processes of 
 thought and going on to the machinery by which 
 ' we live and have our being,' the nervous mechan- 
 ism is gradually thrown out of gear." 
 
 These changes have been most fully studied in 
 the brains of animals poisoned with alcohol, but 
 Dr. Berkeley at Johns Hopkins Hospital has 
 shown that they may also be demonstrated in the 
 brain of a human being who has been an habitual 
 drinker. 
 
 Such a draught on the brain structure, with the 
 inevitable attendant loss of mental power, is a 
 high price to pay for the transient pleasures of 
 alcoholic indulgence.
 
 H4 Adding Years to Your Life 
 
 Syphilis and Brain Decay 
 
 There are various toxins of bacterial origin that 
 have an effect on the brain that is closely similar 
 to the effect of alcohol. Of these by far the most 
 important from the present standpoint is the 
 poison generated by the spirochete of syphilis. 
 This is, indeed, the most important direct agency 
 in the causation of brain maladies, next to al- 
 cohol. 
 
 Not only may syphilis cause degeneration of 
 the arteries of the brain and destructive tumors 
 (called gummata) in that organ; but it also threat- 
 ens its victim with the most pitiful and hopeless 
 of all forms of insanity, general paralysis, or 
 paresis, colloquially known as softening of the 
 brain. 
 
 This terrifying disease, which hurries tlie pa- 
 tient to complete dementia and an early death, 
 never comes to anyone who has not had syphilis ; 
 hence it may properly be spoken of as a terminal 
 form of that malady. 
 
 General paralysis is a very common form of 
 insanity. The paretics that come to the New York 
 Hospitals for the Insane each year amount to 17 
 per cent of all men and 8 per cent of all women 
 admitted. The pitiful and hopeless decay of 
 mentality that these patients exhibit is matched 
 by the destructive lesions of their brains, as may 
 readily be demonstrated post mortem, both by 
 macroscopic inspection and by study of the brain 
 tissues under the microscope.
 
 Is Your Brain All Right? 115 
 
 The brain will be seen to be actually shrunken 
 in size, a layer of watery fluid taking the place 
 of the withered brain tissues. The arteries are 
 thickened and their walls altered in texture. The 
 cells of the cortex the all-essential gray matter 
 have undergone degenerative changes ; many of 
 them are altogether obliterated, and their place 
 taken by tissues that are as useless for purposes 
 of mental activity as so much putty. 
 
 The proportion of cases in which syphilis ulti- 
 mately leads to this result is appallingly large. 
 
 A very careful analysis has recently been made 
 of the cases of syphilis among officers of the Aus- 
 trian army during a long term of years, the aggre- 
 gate number being 41,000. Most of these cases 
 were doubtless given the very best medical treat- 
 ment, yet nevertheless 4.6 per cent of all syphi- 
 litics, or almost one in twenty, were finally strick- 
 en with paresis. 
 
 The proportion would probably be much larger 
 could full statistics be gathered of persons in 
 civic life, who on the average would be less ef- 
 fectively treated in the early stages of the dis- 
 ease than were the Austrian officers. 
 
 Syphilis itself is a disease of many painful 
 manifestations in its earlier stages ; the likelihood 
 that it may lead to this termination in the most 
 fatal and deplorable of mental maladies, should 
 be an additional warning against the well-known 
 lapses of moral conduct through which the disease 
 is acquired. 
 
 " Over the door of every immoral resort," says
 
 u6 Adding Years to Your Life 
 
 a leaflet recently issued with the authority of lead- 
 ing alienists, * * might truthfully be written : ' In- 
 curable insanity may be contracted here.' If 
 self-respect, the desire for the good opinion of 
 others, the influence of religious training, and the 
 attractions of home life are not sufficient to pre- 
 vent this kind of wrong doing; the danger of 
 contracting a disease which may result in incur- 
 able insanity should be sufficient." 
 
 I wish I could bring that thought-provocative 
 paragraph to the attention of every boy and 
 young man, of every father of sons, and of every 
 educator of youth in America. No comment could 
 add to it. No amount of sermonizing could ap- 
 proach it in forceful suggestiveness.
 
 Are Your Nerves in Tune? 
 
 you ever suffer from " nerves " f Are 
 you at times cross, fidgety, unstrung, irrita- 
 able, apprehensive, despondent? Do you ever get 
 in such a state that your friends say your nerves 
 are on the outside? Then read this chapter 
 and find out what to do about it. 
 
 You know that you have a nervous system ; but 
 did you know that you have two of them ; and that 
 one sometimes treats the other badly? Did you 
 know that your secondary nervous system per- 
 forms miracles every hour that no scientist could 
 duplicate in his laboratory? There are more cells 
 in your body than there are people in all the 
 world, and every cell is an individual organism 
 that must be fed and exercised and renovated by 
 the removal of its waste products. 
 
 The secondary nervous system, of which you 
 perhaps never heard, performs this work, a far 
 more wonderful task than anything you ever do 
 consciously. 
 
 The wisest physician in the world could not 
 care for one of these cells a single hour as your 
 sympathetic nerve-ganglia care for the billions; 
 the most skilful surgeon could not repair a pin- 
 scratch without the aid of these nerves. 
 
 117
 
 n8 Adding Years to Your Life 
 
 Yet this wonderful apparatus needs your assist- 
 ance. How do you aid in the work it carries on 
 in your behalf? It is more than likely that you 
 do not do your part very well. Yet if you treat 
 this other self of yours badly, you must pay the 
 penalty and the penalty is " nerves " of the 
 kind you do not relish. These pages will show you 
 your duty to yourself, and attempt to point the 
 way to a healthier and happier way of living. 
 
 Like a Telephone System 
 
 There has recently been founded in New York 
 City a new kind of clinic called the Neurological 
 Institute. Several of the most prominent nerve 
 specialists have combined forces to start this in- 
 stitution, which, as its name implies, will be de- 
 voted to the treatment of the various nervous 
 diseases. 
 
 The establishment of such an institution is 
 symbolic of the times. We are all familiar with 
 the assertion that this is a nervous age, and a good 
 many evidences are at hand that tend to prove 
 the assertion. In the cities in particular, under 
 the conditions of hurry and stress that there ob- 
 tain, neurasthenia or nervous prostration has 
 become more and more popular. But similar con- 
 ditions are becoming increasingly familiar among 
 the patients of the country doctor as well. And 
 indeed this is inevitable, for nervous breakdown 
 follows under strain almost as a matter of course, 
 and everyone knows that the conditions of the
 
 Are Your Nerves in Tune? ng 
 
 past few years have added to the average stress 
 of living. 
 
 But just what do we mean when we speak of 
 " nervous breakdown " ? The words are on 
 everyone's lips, but like a good many other fa- 
 miliar phrases this one is not always clearly un- 
 derstood by those who use it. To gain an inkling 
 of what the words really imply we must briefly 
 consider the normal functions of the nerves. 
 
 These functions, it appears, are exceedingly 
 simple, notwithstanding the complex conditions 
 that result from their derangement. It is scarcely 
 an exaggeration to say that the sole function of 
 the nerves is to convey impulses. 
 
 They are in effect telephone wires carrying 
 messages from one part of the organism to an- 
 other, and from the outside world to the central 
 nervous mechanisms. 
 
 The resemblance between the nervous system 
 and a telephone system is really striking ; but the 
 analogy is complete only when we consider the 
 telephone services of those cities London and 
 Los Angeles, for instance that have two rival 
 telephone companies in the same territory. For 
 the human body has its two sets of nerves per- 
 meating to every nook and cranny of the organism, 
 each set largely independent of the other, and 
 each sending its fibres (conducting wires) to an 
 independent receiving station or central office. 
 
 One series of receiving stations consists of a 
 chain of small ganglia, or networks of nerve cen- 
 tres, extending along the spinal column, within
 
 120 Adding Years to Your Life 
 
 the body cavity, supplemented by similar gan- 
 glionic stations, all relatively small and inconspic- 
 uous, in various other cavities of the body. This 
 meshwork of ganglia, together with the nerve 
 cords that connect with it and run in all directions 
 to find their chief termini in the organs of the 
 body and in the blood vessels and lymphatics, is 
 called the sympathetic system. 
 
 In vast numbers of lower organisms, including 
 all creatures below the vertebrates, this is the 
 only nervous mechanism. 
 
 But in man and his allies of the great tribe of 
 vertebrates, a second system of nerve centres has 
 been evolved a rival or supplementary telephone 
 system which is far more complex, and from the 
 standpoint of the intellectual life vastly more im- 
 portant than the original one. The central sta- 
 tions of this system are known as the brain and 
 spinal cord. To protect these masses of nerve 
 cells, the skull and spinal column were evolved, 
 and the entire structure of all higher animals was 
 modified accordingly. 
 
 The nerves that go out from the brain and 
 spinal cord connect at their free ends with muscle 
 fibres, or they are spread out to form a meshwork 
 in the skin, or they are modified to serve the pur- 
 poses of the organs of special sense. 
 
 It is these nerves, conveying their message to 
 the spinal cord and brain, that are involved 
 wherever we are conscious of any contact with 
 the other world, either through the tactile sense, 
 or through the sense of taste, smell, -icr.ring, or
 
 Are Your Nerves in Tune? 121 
 
 sight. The impressions from the world as gained 
 by the skin, or tongue, or eye, or ear, set up 
 " nervous impulses " that are transmitted to the 
 appropriate centres in the brain, and these cen- 
 tres interpret the impressions as states of con- 
 sciousness which we speak of as sensations. 
 
 The Brain Mechanism 
 
 If you could look back into this great receiving 
 station in your head with the eyes of the micro- 
 scope, you would find that each nerve fibril that 
 comes to it from the outlying regions of your 
 body terminates finally in a minute ganglion cell. 
 There are millions of these cells, arranged in 
 rather definite layers scattered everywhere 
 through the gray matter or cortex of the brain. 
 Certain localized groups are given over to the re- 
 ception of each kind of impression, and the nerve 
 cells that control definite functions are similarly 
 localized. But they are intermeshed and linked by 
 connecting fibrils. 
 
 There are, for example, a few convolutions near 
 the centre of the brain where the cells are located 
 that directly control the activities of the voluntary 
 muscles. Injury to this small area would cause 
 paralysis of the groups of muscles on the opposite 
 side of the body, for a large number of nerve 
 tracts cross over from the right side of the body 
 to the left side of the brain and vice versa. 
 
 Again, there is a small area in the left frontal 
 region, the brain cells of which control the memory
 
 122 Adding Years to Your Life 
 
 of words as used in ordinary speech. Injury to 
 this region may cause so-called aphasia, with its 
 characteristic symptom of incapacity to talk be- 
 cause the names of things cannot be recalled, even 
 though the individual is perfectly conscious and 
 retains all other evidences of intelligence. 
 
 As to the more abstract processes of mind, the 
 localization of cells is less specifically known. In 
 point of fact it seems probable that for the proc- 
 esses of intellection large numbers of the cells 
 are involved, and that these cells are scattered in 
 widely different regions of the brain, being linked 
 with connecting nerve fibrils which run every- 
 where through the central substance of the brain, 
 like telephone wires connecting the numberless 
 telephones of a system. 
 
 The processes of memory, we may suppose, are 
 associated with the reproduction of cellular activi- 
 ties of the brain which duplicate vibrations that 
 came to them at an earlier period. 
 
 As for the messages that go out from the brain, 
 along the nerves of the sensory-motor system, it 
 is rather startling to discover that these consist 
 solely of orders transmitted along the motor 
 nerves to the fibres of muscles, directing these 
 fibres to contract. Intricate and elaborate as are 
 the brain processes, with their conscious equiva- 
 lents, the sole method by which the brain is able 
 to control the body it dominates is by thus direct- 
 ing the activities of the muscles. 
 
 It is necessary to have an exceedingly intricate 
 system of nerves devoted to this purpose because
 
 Are Your Nerves in Tune? 123 
 
 it is absolutely essential that the several hundred 
 mucles of the body should operate in harmony. 
 
 What results when there is any disarrangement 
 of this harmonizing central mechanism is well il- 
 lustrated in the convulsive seizures of a victim 
 of the familiar disease called epilepsy. In the 
 epileptic seizure each muscle of the individual is 
 acting normally, but through lack of cerebral con- 
 trol the muscles are all put into action simulta- 
 neously, one set opposing another in a hopelessly 
 inco-ordinate struggle that amounts to a civil war 
 among the members of the bodily organism. 
 
 Under normal conditions, on the other hand, 
 the messages sent out from the central mechanism 
 are so skilfully regulated that harmonious groups 
 of muscles are put into action together and oppos- 
 ing muscles rendered quiescent. 
 
 You could never so much as bend your elbow 
 if the triceps muscles at the back of your arm 
 did not relax while the biceps muscles are con- 
 tracting. 
 
 In producing this harmonious action of the 
 muscles, the function of the nerves proper, as we 
 have seen, is merely to transmit impulses from 
 the central generating station. Yet the absolute 
 importance of the transmitting nerves is easily 
 demonstrated ; for if one of these nerve tracts is 
 severed say, by a knife wound the muscles 
 supplied by that nerve becoming instantly 
 ' * paralyzed ' ' ; they remain totally quiescent not- 
 withstanding any commands that the brain cells 
 may attempt to give them.
 
 124 Adding Years to Your Life 
 
 Here again the likeness to the telephone system 
 is obvious: the wires must be intact or no mes- 
 sages can be transmitted. 
 
 The Action of the Sympathetic System 
 
 , The activities of the brain are primarily asso- 
 ciated with the familiar phenomena of conscious- 
 ness. 
 
 Under normal conditions, we can consciously 
 control the messages that result in action of the 
 bodily muscles. We can move our arms or feet 
 or actuate the muscles of the vocal apparatus at 
 will. It is true that many movements that are 
 habitually repeated come to take place, as it were, 
 automatically and without conscious direction. 
 The movements involved in walking furnish a 
 familiar illustration. The action of the chest in 
 breathing is an even more striking instance. But 
 it is possible to bring these movements within the 
 scope of consciousness, and to direct them at will 
 by fixing attention upon them. 
 
 There are other sets of bodily activities, how- 
 ever, that are not subject to such voluntary con- 
 trol. 
 
 Such, for example, are the activities of the 
 entire apparatus of digestion and assimilation, 
 the all-important and unceasing action of the 
 heart, and the contraction and relaxation of the 
 muscular coats of the arteries and arterioles by 
 which the distribution of the blood in the body is 
 largely controlled.
 
 Are Your Nerves in Tune? 125 
 
 The function of breathing also falls, in the last 
 analysis, among those essential life processes that 
 are not dominated by the conscious mind ; whereas 
 we can regulate the breathing muscles within cer- 
 tain bounds, we cannot prevent their operation 
 altogether. However hard you try to hold your 
 breath, the " automatic " control of the breath- 
 ing apparatus will presently overmaster the con- 
 scious effort at retardation. 
 
 In a word, then, it is obvious that the so-called 
 " vital " functions, those that must be perpet- 
 uated in operation in order to maintain life, are 
 placed beyond control of the conscious mind. 
 They are, in point of fact, controlled by the sym- 
 pathetic system of ganglia scattered throughout 
 the body cavities. The relatively inconspicuous 
 ganglia that control this system have the needs of 
 the organism constantly under surveillance. 
 
 It appears, then, that the two telephone sys- 
 tems of the body are not rival systems; they are 
 complementary. 
 
 If the bodily mechanism tends to run short of 
 fuel, the sympathetic ganglia telegraph a message 
 to the conscious brain centres which is interpreted 
 as a sensation of hunger. The muscles under 
 conscious control then secure food and convey it 
 to the stomach. 
 
 But here the sympathetic ganglia resume con- 
 trol. They send messages which cause relaxation 
 of the walls of the blood vessels supplying the 
 stomach and other digestive organs, so that an 
 increased flow of blood to these parts takes place.
 
 126 Adding Years to Your Life 
 
 Thus stimulated the various glands of the stom- 
 ach and intestines and liver and pancreas secrete 
 the digestive fluids that transform the food into 
 absorbable compounds. If meat has been eaten 
 largely, the supply of gastric juice must be plen- 
 tiful; for fatty and starchy foods, pancreatic and 
 hepatic juices must be supplied in just the right 
 quantity. 
 
 All this is controlled by the sympathetic ganglia. 
 So are the further steps through which this as- 
 similable material is taken up by the lacteals and 
 ultimately distributed to the uttermost parts of 
 the body, there to be used in rebuilding broken 
 down tissues or as fuel for the bodily machine in 
 general. 
 
 And under normal conditions, these varied ac- 
 tivities are performed so independently of the 
 brain centres as to leave no record in conscious- 
 ness. 
 
 These miraculous transformations are going on 
 in your body, such transformations as no chem- 
 ist could duplicate, in the laboratory, and you 
 are utterly unconscious of the entire procedure. 
 Your brain is busy with other duties, or is sleep- 
 ing it matters not: the perpetual vigilance of 
 the sympathetic system keeps the commonwealth 
 of cells and tissues of many types in healthful 
 activity. 
 
 There is, nevertheless, the closest harmony of 
 action between the two nerve systems, notwith- 
 standing the different systems of organs which 
 they control.
 
 Are Your Nerves in Tune? 127 
 
 Take a simple illustration. Your brain mechan- 
 ism, under certain stimuli, determines that your 
 body shall enter into vigorous action. You de- 
 cide, let us say, to participate in a running match. 
 Your muscles, as directed by your brain through 
 impulses sent along motor nerves, are caused to 
 contract with great vigor, and as such contraction 
 is associated with a large consumption of fuel and 
 the liberation into your veins of excessive quanti- 
 ties of waste products, it becomes instantly neces- 
 sary to safeguard the bodily mechanism as a 
 whole. There must be an accelerated flow of 
 blood, the lungs must functionate more quickly to 
 supply oxygen and remove carbonic acid gas ; and 
 the blood vessels at the surface must be opened 
 to full capacity, and the perspiratory glands put 
 into full action to facilitate the elimination of 
 heat lest the bodily temperature be raised to a 
 dangerous level. 
 
 And the unconsciously operated sympathetic 
 mechanism proves equal to these needs. Your 
 heart beats with redoubled speed and force. Your 
 breathing becomes rapid and deep, your skin is 
 flushed, and perspiration breaks out all over your 
 body. 
 
 You have had no conscious thought of anything 
 beyond the muscular exertion involved in run- 
 ning; but the sympathetic mechanism has op- 
 erated in harmonious coalition with the spinal 
 cord and brain, with the result that a whole coterie 
 of essential functions lying beyond the control of 
 the conscious mind, many of them utterly beyond
 
 128 Adding Years to Your Life 
 
 the pale of consciousness itself, has become 
 operative. 
 
 It is a marvelous coalition, this federation of 
 the two great seemingly independent nervous 
 systems. Neither system could do the work of 
 the other; each must find support in the other; 
 working together they control the most wonder- 
 ful of all mechanisms, the bodily machine; work- 
 ing in harmony they ensure that mechanism life 
 and health and strength within its hereditary 
 limitations; but if either fails or if either shirks 
 its share of duties, disaster results and the organ- 
 ism falls prey to disease. 
 
 Imposing on Your Other Self 
 
 To get a clear idea of the situation, we must 
 recall that there are in your body more cells than 
 there are people in all the world, and that every 
 cell is an individual organism that must be fed 
 and exercised, and renovated by removal of its 
 waste products. 
 
 The sympathetic nervous system controls this 
 vast population, and attends to its needs. Every 
 individual cell, located in any out of the way part 
 of your body must have its appropriate modicum 
 of food brought to it through blood vessels and 
 lacteals, and the waste products of its activity 
 must be promptly removed; otherwise your or- 
 ganism would very soon suffer complete demora- 
 lization and all activity would be at an end, that 
 is to say, you would die.
 
 Are Your Nerves in Tune? 129 
 
 The function of the sympathetic nervous sys- 
 tem might then be likened to that of the commis- 
 sary department of an army. 
 
 The supplying of food, and the general routine 
 of hygiene, as applied to the army, is a service that 
 gives little glory in comparison with the mar- 
 shaling of the troops in battle array, and the 
 strategy that makes for the winning of battles ; but 
 it is an absolutely essential service none the less. 
 
 And so the unconsciously operated activities of 
 the sympathetic nervous system, which are re- 
 sponsible for the bodily functions, are absolutely 
 essential to your well-being, however your con- 
 scious mind may be disposed to regard these mere 
 " animal " activities. 
 
 But what shall we say of the manner in which 
 you, as a conscious personality, carry on your 
 part of the work necessary to the harmonious 
 operation of the two nervous systems? The sym- 
 pathetic system, as we have seen, is absolutely 
 dependent on the brain system for the supply of 
 materials with which it operates. How does your 
 brain the arbiter of your conscious ego per- 
 form its share of the divided labors? 
 
 If you consider the matter attentively, you will 
 probably be disposed to admit that the answer is 
 not greatly to your credit. 
 
 More than likely you supply the digestive ap- 
 paratus, which is the laboratory wherein the sym- 
 pathetic nervous system directs the preparation 
 of materials for feeding its vast army of cells, 
 with food that is often of doubtful quality, or
 
 130 Adding Years to Your Life 
 
 wrongly apportioned in its properties, or what 
 in the end is almost as bad in excessive quantity. 
 
 The result is that the sympathetic nerve ganglia 
 are put to their wits' end to know how to make 
 bad materials into wholesome nourishment. 
 
 They have thrust on them an excessive supply 
 of starch and sugars calculated to excite mutiny 
 in the ranks of muscle cells that demand proteids. 
 
 Or, on the other hand, they receive an excessive 
 quantity of proteids because your palate chances 
 to be overfond of meat when the crying need is 
 for starchy or fatty fuels. 
 
 The excess quantities of one kind or another 
 must be removed and either stored away in out 
 of the way corners of the organism say, as fat 
 about the waist region or eliminated promptly 
 through the various excretory organs, notwith- 
 standing the undue strain that is thus put upon 
 these organs, to prevent the disastrous poisoning 
 of whole galaxies of cells. 
 
 All these tasks the sympathetic nerves direct 
 with marvelous efficiency. They have inherited 
 their skill from thousands of generations of an- 
 cestors, and they manipulate the intricate ap- 
 paratus of their wonderful chemical laboratory in 
 a way that far surpasses all the possibilities of 
 conscious human action. But they feel the stress 
 of abnormal living none the less, and there are 
 limits to the possibilities of their setting right 
 the disorganizing influences which your conscious 
 derelictions of diet impose upon them. 
 
 In particular their task becomes difficult if, as
 
 Are Your Nerves in Tune? 131 
 
 is more than likely, you give them an inadequate 
 supply of oxygen, because you prefer to live and 
 sleep in ill-ventilated rooms. 
 
 Perhaps you further complicate their problem 
 by introducing out and out poisons, such as al- 
 cohol and nicotine and caffeine, which tend to 
 paralyze the activities of the digestive laboratory 
 and interfere with the normal preparation of 
 pabulum for the cells. 
 
 It is even probable that you are neglectful about 
 so fundamental a matter as the supply of ade- 
 quate quantities of that great universal diluent 
 and solvent, water, without which the most skilful 
 laboratory workers of the digestive system 
 cannot properly perform their labors. 
 
 Against these impositions the sympathetic 
 nervous system usually makes no protest. It 
 labors incessantly day and night to make the best 
 of the hard task you set it to correct, as far as 
 may be, the mistakes that you, the consciously 
 directive and supposedly intelligent member of 
 the coalition, are constantly making. If too 
 greatly imposed upon, however, the ganglia of 
 the sympathetic system at last make protest that 
 is heard at the headquarters in the brain 
 registered usually in the form of disagreeable or 
 painful sensations which you interpret as indi- 
 gestion, mal-nutrition, or aches variously located 
 or as a general condition of depression. 
 
 Then the response you make is, not to correct 
 the errors of your diet and hygiene, but to go to 
 a physician and ask for some magic drug that
 
 132 Adding Years to Your Life 
 
 will set right the complex machinery at a dose, to 
 make amends for all your hygienic sins of com- 
 mission and omission. 
 
 The doctor cannot supply such a remedy of 
 course; he would have greater skill than the 
 chemists of the sympathetic nervous system itself 
 if he could. But he will give you something to 
 palliate your symptoms, accompanied with good 
 admonitions that you will for the most part fail to 
 heed; and, after a momentary period of relief 
 you will go on imposing upon the patient and 
 long-suffering sympathetic nervous system that 
 constitutes your other self in the same reckless 
 manner as before. 
 
 Not a commendable way, surely, for a com- 
 mander-in-chief to treat a loyal, efficient, and 
 ever vigilant lieutenant of the all-important com- 
 missary department : that you will admit. 
 
 Imposing on Brain and Spinal Cord 
 
 Of course your derelictions of diet and general 
 hygiene, which thus put impossible tasks upon the 
 sympathetic nervous system, and which inevita- 
 bly accomplish the derangement of function of 
 various and sundry of your bodily tissues, will 
 make its influence felt on that other nervous sys- 
 tem which has for its most conspicuous organs, the 
 spinal cord and brain. For these important struc- 
 tures are not only directly linked with all the 
 tissues of the body by nerve cords, but their cells 
 are themselves physical structures which depend
 
 Are Your Nerves in Tune? 133 
 
 no less than muscle cells or gland cells on the 
 good offices of the sympathetic system for their 
 food supplies and for the removal of the waste 
 products of their activity. 
 
 So your ill-treatment of the sympathetic sys- 
 tem reacts upon the brain and results directly in 
 the lowering of its power of energizing upon 
 which all your mental functionings depend. Now 
 things are working in a vicious circle. 
 
 But in addition to this, it is more than likely that 
 you put a further handicap upon your brain and 
 the nervous apparatus with which it is directly 
 connected by the tasks to which you subject it. 
 
 For example, it is probable that your habits of 
 mental work are not of the best. It is likely that 
 you have never learned the value of regular 
 sequence of work time and rest time for your brain 
 which proper habits of sleeping would give. 
 
 It is likely that you subject your brain to pe- 
 riods of undue stress through overwork ; that you 
 subject it to the wearing influence of worry or of 
 fits of temper. 
 
 It is probable that you take into your system 
 more or less regularly drugs that directly inter- 
 fere with the normal functioning of the brain 
 cells, of which drugs alcohol, nicotine, and caf- 
 feine are the most familiar examples. 
 
 All these things constitute impositions on the 
 brain cells whose proper functioning is absolutely 
 essential to your normal mental activity. And 
 the inevitable result of such imposition is that 
 the brain cells perform their functions less effi-
 
 134 Adding Years to Your Life 
 
 ciently than they otherwise would do. It is dem- 
 onstrable under the microscope that brain cells 
 that have been overworked suffer an actual break- 
 down of their substance so that they become vacuo- 
 lated, as the technical phrase is ; that is to say, por- 
 tions of the active cell substance are substituted 
 by droplets of serum that have no more power 
 of nervous functioning than so much water. 
 
 If the strain is not too long continued, the brain 
 cells may be repaired and restored to their nor- 
 mal condition ; but if the imposition is carried too 
 far there results actual and permanent degenera- 
 tion of the brain cells themselves. 
 
 Such a condition of the brain cells is noted, for 
 example, in those extreme cases in which the 
 brain has been subject to the toxic influence of 
 alcohol habitually for prolonged periods. The 
 brain of the dipsomaniac becomes shrunken 
 through decay of its essential cells, and a layer of 
 watery fluid between the brain surface and its 
 surrounding membranes takes the place of the 
 essential nerve tissues. 
 
 This is further accentuated if the virus of 
 syphilis has been added to the toxic influences 
 operating against the brain cells. In that case 
 the decay of cells may become so noticeable as to 
 lead to almost complete abolition of mentality. 
 Frequently the walls of the arteries supplying the 
 brain become weakened through degeneration of 
 their cells, and hemorrhage into the brain sub- 
 stance causes permanent paralysis or ends the 
 life of the patient outright.
 
 Are Your Nerves in Tune? 135 
 
 Short of these extreme cases, however, the brain 
 that is subject to the disturbing influence of mal- 
 nutrition and overwork and worry and uncon- 
 trolled bursts of emotion carries a perpetual 
 handicap in attempting to perform its function of 
 co-ordinating the messages that come to it and 
 regulating the responsive muscular activities. It 
 is the brain thus harassed that becomes abnor- 
 mally susceptible to impulses from the outer world 
 and erratic and inco-ordinate in its responses to 
 impulses in general. 
 
 The person whose brain cells are thus malad- 
 justed becomes unduly sensitive to noises or 
 disturbances of any sort. 
 
 He is irritable and emotional ; he cannot adjust 
 himself to the minor annoyances that are inevi- 
 table in business and social life. He becomes 
 painfully conscious of the perverted functioning 
 of his visceral system. 
 
 He is afflicted with exaggerated sensations 
 which may take the form of acute pains or of a 
 pervasive sense of ill-being, apprehension, and 
 hypochondria. 
 
 Worst of all, his harassed brain cells reach a 
 stage of sensitiveness in which they are perpet- 
 ually responsive to the messages sent to them 
 from various parts of the body. This means 
 that he cannot sleep : and prolonged wakefulness 
 in itself produces further exhaustion of the brain 
 cells, as the experiments of Dr. George W. Crile, 
 the famous Cleveland surgeon, have recently 
 shown.
 
 136 Adding Years to Your Life 
 
 When your nervous mechanism has reached 
 such a stage of derangement as this, you are said 
 to be suffering from neurasthenia or nervous 
 prostration. Your less charitable friends are apt 
 to say of you that your nerves are on the outside 
 of your skin. But what is really at fault, as we 
 have seen, is not so much the nerves themselves, 
 which after all only convey the impulses that come 
 to them, as the essential cells of the spinal cord 
 and brain where these impulses are normally 
 gathered and controlled or co-ordinated. 
 
 Your telephone wires may be all right. It is 
 the receiving and transmitting apparatus that is 
 at fault. 
 
 Remedies Versus Prevention 
 
 The specialist to whom you apply prescribes 
 just what you might expect, now that you know 
 what caused your condition of " nerves." 
 
 He puts you on a rational diet, and tells you to 
 drink plenty of water and little of anything else 
 unless it be milk; to live in the open and inhale 
 any amount of oxygen; to stop work and worry, 
 and if possible to get into the country where 
 things are quiet and your tired brain cells can 
 have a rest. Perhaps he treats you with a high 
 frequency electric current, to soothe your muscles 
 and arteries ; he may use the resources of hydro- 
 therapy to stimulate your enervated and rebel- 
 lious tissues; he counsels rest in bed or exercise 
 in the open, according to your precise stage of 
 cellular demoralization. Or he may combine most
 
 Are Your Nerves in Tune? 137 
 
 of these prescriptions in one by ordering you to 
 the Hot Sprjngs. 
 
 This is all very well ; but would it not have been 
 a good deal better, from your standpoint, to have 
 avoided the need of these prescriptions? Is not 
 this pre-eminently a case where prevention is 
 better than cure? Obviously; but how prevent a 
 disaster of such insidiousness of approach and of 
 such varied factors of causation? 
 
 To be sure you might have rationalized your 
 diet and your habits of exercise, and that would 
 have done much for you. 
 
 But what about the derangements due more 
 specifically to perverted activities of the brain? 
 
 It is easy enough to counsel moderation and the 
 avoidance of overwork and worry, and the like; 
 but it is obvious that advice as to these things 
 may partake more or less of the admonition to 
 lift one's self up by one's boot straps. 
 
 The average man does not overwork of mere 
 choice; he does not worry because he prefers to 
 do so; he does not even give way to bursts of 
 temper without effort to control his emotions. If 
 he subjects his brain to these disturbing influ- 
 ences, he does so because he knows not how to 
 avoid such disturbances. The conditions of his 
 environment are really responsible for his cere- 
 bral maladjustment. His brain cells give inco- 
 ordinate responses and suffer undue fatigue 
 because impulses that come to them from the 
 outer world are excessive, or maladjusted to their 
 capacity.
 
 138 Adding Years to Your Life 
 
 Square Pegs and Round Holes 
 
 And it is precisely here that the modern psy- 
 chologist steps into the field and offers a solution 
 of the problem of adjustment of the average brain 
 to the average environment. The difficulty, says 
 the psychologist, which primarily leads to the 
 observed condition of undue nervousness and an 
 unwarranted number of nervous breakdowns, is 
 that a very large number of brains, under the 
 existing condition, are so trained that they do not 
 have a fair chance to functionate normally. 
 
 One reason is that the young men and women of 
 our time very generally select their vocations 
 haphazard and without reference to their fitness 
 or unfitness for the tasks. Thus there are num- 
 bers of misfits, square pegs in round holes, as 
 the saying is. 
 
 As a consequence, work is performed badly and 
 inefficiently, while the workers themselves suffer 
 undue strain attempting to keep pace with other 
 workers who are inherently better adapted for 
 that particular task. 
 
 Take by way of illustration a specific case cited 
 by one of the prominent modern students of effi- 
 ciency in business, Mr. Harrington Emerson. 
 11 The type for the great newspaper," he says, 
 " is set up by linotype operators. Apprentice- 
 ship is rigorously limited. Some operators can 
 never get beyond the 2500-em class, others with 
 no more personal effort can set 5000 ems. Do 
 the employers test out applicants for the appren-
 
 Are Your Nerves in Tune? 139 
 
 ticeship so as to be sure to secure boys who will 
 develop into the 5000-em class? They do not; 
 they select applicants for any near reason except 
 the fundamental important one of innate fitness." 
 
 It is obvious that under these conditions a good 
 share of the workers will be in the 2500-em class, 
 and that these all their life will be subject to un- 
 due strain in attempting to compete with their 
 5000-em co-workers. 
 
 And this specific case is typical of what applies 
 in a thousand other lines of work, both mechani- 
 cal and mental. 
 
 Mr. Emerson believes that the difficulty might 
 be met by providing that young men and women 
 to enter any given trade or profession should be 
 selected by competent specialists who have " sup- 
 plemented natural gifts and good judgment by 
 analysis and synthesis that enable them to per- 
 ceive aptitudes and proclivities even in the very 
 young, much more readily in those semi-matured, 
 and can with almost infallible certainty point out, 
 not only what work can be undertaken with fair 
 hope of success, but also what slight modification 
 or addition and diminution will more than double 
 the personal power." 
 
 The Psychologist to the Rescue 
 
 But Professor Hugo Miinsterberg, the Harvard 
 psychologist, very much doubts the availability of 
 any such intuitional power as this. He would pin 
 his faith rather to the methods of laboratory, and
 
 140 Adding Years to Your Life 
 
 would attempt to substitute the results of scien- 
 tific investigation for what he terms mere guess- 
 work. In illustrating what may be done in this 
 direction, Professor Miinsterberg cites various 
 interesting cases. 
 
 He tells, for example, how Mr. S. A. Thompson 
 applied the method of the psychological labora- 
 tory to testing the workers in a bicycle factory 
 where 120 girls were inspecting the balls. The 
 results of this test were so remarkable that they 
 may well be given in detail. The case is pecu- 
 liarly interesting because the work involved was 
 of so simple a character that it might almost be 
 thought that one person of average intelligence 
 could do it as well as another. 
 
 The task was this : The girls had to place a row 
 of small polished steel balls on the back of the left 
 hand, and while they were rolled over and over in 
 the crease between two of the fingers placed to- 
 gether, they were minutely examined in a strong 
 light, and the defective balls were picked out by 
 the aid of a magnet held in the right hand. 
 
 A simple enough task, even though requiring 
 close attention and concentration. But now note 
 what Professor Miinsterberg says : 
 
 " The girls were working ten and a half hours 
 a day. Mr. Thompson soon recognized that the 
 quality most needed, beside endurance and indus- 
 try, was a quick power of perception accompanied 
 by quick responsive action. He knew that the 
 psychological laboratory has developed methods 
 for a very exact measurement of the time needed
 
 Are Your Nerves in Tune? 141 
 
 to react on an impression with the quickest pos- 
 sible movement ; it is called the reaction-time, and 
 is usually measured in thousandths of a second. 
 He, therefore, considered it advisable to measure 
 the reaction-time of the girls, and to eliminate 
 from service all those who showed a relatively 
 long time between the stimulus and reaction." 
 
 The test resulted, we are told, in showing that 
 many of the most intelligent, hardest-working, and 
 most trustworthy girls were not naturally fitted 
 for the task. 
 
 When these misfits were eliminated, it was 
 found possible to shorten the hours and reduce 
 more and more the number of workers, with the 
 final outcome that thirty-five girls did the work 
 formerly done by a hundred and twenty, and that 
 the accuracy of the work at the higher speed was 
 two-thirds greater than at the former very slow 
 pace. 
 
 11 This allowed almost a doubling of the wages 
 of the girls in spite of their shorter working-day, 
 and at the same time a considerable reduction in 
 the cost of the work for the factory." 
 
 From Laboratory to Work Shop 
 
 Such a result is surely stimulative. And there 
 is no reason to suppose this an exceptional case. 
 But the work is only begun. 
 
 Professor Miinsterberg, however, has been led 
 to take the matter up in his laboratories, in the 
 endeavor to develop tests that might be of practi-
 
 142 Adding Years to Your Life 
 
 cal value in selecting applicants for various lines 
 of work. 
 
 It should be explained that the delicate ap- 
 paratus of the psychological laboratory enables 
 the experimenter to test such important matters 
 as the reaction-time of any given brain to a given 
 stimulus, the time required by the brain cells of a 
 given individual to make a selective judgment, and 
 the like ; and that different brains differ very ma- 
 terially as to these important and fundamental 
 reactions. It is obvious that there are many lines 
 of work in which quick reaction-time is one of the 
 most important elements for the development of 
 efficiency, just as in the case just cited. 
 
 But it is seldom possible without careful analy- 
 sis to determine just what the elements are in any 
 given case. In Professor Miinsterberg's words, 
 " The subtler nuances of difference between tasks 
 can be gained only by an intimate knowledge of 
 the industry." And he gives this very striking 
 illustration : 
 
 1 ' In the case of a well-known type-setting ma- 
 chine, thousands of which are in daily use, I had 
 the impression that the rapidity of the perform- 
 ance was dependent upon the quickness of the 
 finger reaction. The managers, on the other 
 hand, have found that the most essential condition 
 for speed in the whole work is the ability to re- 
 tain a large number of words in memory before 
 they are set. The man who presses the keys 
 rather slowly advances more rapidly than another 
 who moves his fingers quickly, but must make
 
 Are Your Nerves in Tune? 143 
 
 many pauses in order to find his place in the manu- 
 script and to provide himself with new words. ' ' 
 
 Commenting on this case, Professor Miinster- 
 berg analyzes the factors that must be brought 
 into correlation if we are to enable the individual 
 to make a wise selection of a vocation. We must 
 consider, he says, ' ' first the actual experiences of 
 managers; secondly, the observations of skilled 
 psychologists in the industrial concerns; thirdly, 
 psychological and experimental investigations 
 with successful and unsuccessful laborers; and, 
 fourthly, experimental studies of the normal vari- 
 ability." 
 
 He points out that if such a programme is to be 
 realized in detail, it will be necessary to discrimi- 
 nate between inherited traits and those that are 
 acquired. 
 
 Each individual must be studied as to his " ca- 
 pacities of attention and emotion, memory and 
 will energy, disposition to fatigue and to restora- 
 tion, imagination, suggestibility and initiative, 
 and many other features." 
 
 Practical Tests that You Can Apply 
 
 A good deal of this will be doubtless carried out 
 in the schools of the not distant future. In the 
 meantime, you may personally apply practical 
 tests to yourself and your children that will be of 
 the utmost value, even though you have scant 
 knowledge of psychology. 
 
 You can, for example, see that your children's
 
 144 Adding Years to Your Life 
 
 eyes, ears, noses, throats, and teeth are cared for. 
 Defects of any of these organs may be sources of 
 constant irritation to the brain. Eye strain, due 
 to some easily remedied error of refraction, may 
 cause more fatigue of the brain than all the studies 
 of the curriculum. Dr. S. Josephine Barker, Di- 
 rector of Child Hygiene in the New York schools, 
 states that among the school children of the 
 metropolis " there are 60,000 cases of defective 
 and untreated eyesight, 65,000 cases of defective 
 nasal breathing, 82,000 enlarged tonsils, and 400,- 
 000 young mouths that harbor diseased teeth. ' ' It 
 would be hard to estimate the amount of brain 
 wear, exhaustion, and actual perversion inadvert- 
 ently resulting. 
 
 You owe it to your children to see that they are 
 not similarly neglected. 
 
 Give careful heed also to the inherent traits and 
 capacities of your children as revealed in their 
 every-day conduct. Teach them nervous control 
 control over their emotions, their passions, their 
 egoistic desires. This will be far more impor- 
 tant than anything they will learn at school. And 
 in aiding them to select vocations, when the time 
 comes for that, consider their traits of mentality, 
 their innate capacities, rather than your own 
 predilections, and be governed accordingly. 
 
 Remember that the square peg in the round hole 
 is at best a slipshod contrivance. " Better a good 
 artisan than a poor artist " is a very wholesome 
 motto. 
 
 As to yourself, you should be able to make an
 
 Are Your Nerves in Tune? 145 
 
 analysis of your own mentality, based on compari- 
 son with the persons with whom you come in con- 
 tact, that will be of inestimable value to you. Test 
 yourself by wholesome introspection never, how- 
 ever, carried to the stage of morbid brooding 
 day by day, and determine to better your quality 
 of brain action, however good it was in the begin- 
 ning. Remember that the all-important thing is 
 brain control capacity to restrain irrational re- 
 sponses, to turn the mind into normal channels, to 
 bar out excessive action along one line, which con- 
 stitutes worriment ; to rest the mind by diverting 
 it into new channels ; to gain new and better habits 
 of seeing, feeling, thinking, and acting. 
 
 Your Brain as a Phonograph 
 
 We have likened the brain system to a telephone 
 system. From another viewpoint it is even more 
 closely comparable to a phonograph. 
 
 But the brain is a far more sensitive and uni- 
 versal recorder of impressions than the phono- 
 graph, because the latter takes note only of the 
 sound waves, whereas the brain makes permanent 
 record of every sensation that comes to it, not 
 alone of sound waves, but of the impressions that 
 are registered as sensations of touch, of taste, of 
 smell, and of sight. 
 
 Each individual cell is a tiny storage battery 
 that accumulates energy, and the cells are grouped 
 together by connecting fibrils. 
 
 From earliest infancy, vibrations of various
 
 146 Adding Years to Your Life 
 
 kinds are being sent into the brain centres along 
 the various nerve paths, and channels of action 
 are being worn smooth as it were, so that particu- 
 lar types of action in response to these specific 
 impulses become more and more easy and " nat- 
 ural." This is what we really mean when we say 
 that certain habits of thinking and acting are be- 
 ing established. 
 
 It is all-important for the individual that the 
 channels of nervous action thus early established 
 should be those that result in right rather than in 
 wrong action. 
 
 Heredity will determine something as to this. 
 We all know, for example, that habits that are 
 easy to acquire for one individual are hard for 
 another, for example, playing on the piano, or re- 
 citing poetry, or learning mathematics. But en- 
 vironment and practice will also determine much. 
 We do not inherit knowledge ; we inherit capacity 
 to learn. The brain at birth is a blank record ; a 
 more or less sensitive one according to its in- 
 herited possibilities, but still a blank with all its 
 possibilities unrealized, and unrealizable except 
 through the right kind of experiences in after life. 
 
 Consider the treatment you give your mental 
 phonograph as regards the matter that comes to 
 it from the printed page along the channels of 
 vision; and ask yourself whether you give your 
 brain a chance to become properly educated. 
 
 You read newspapers doubtless. That is impor- 
 tant; but are newspapers all-sufficient? 
 
 You read novels, and, according to Emerson,
 
 Are Your Nerves in Tune? 147 
 
 novels may be as useful as Bibles, if they teach 
 the right lesson. But do they by themselves sup- 
 ply an all-sufficient mental pabulum? 
 
 If you know by heart all the best fiction in the 
 world, and nothing else, would you be really edu- 
 cated in a proper sense fully equipped for your 
 life work? 
 
 Obviously not. So you need to supply your 
 mind with the records of serious books in which 
 the mature thought of wise men of earlier genera- 
 tions has been recorded and accumulated. You 
 need to supply your brain with matter worth re- 
 membering as material for building an effective 
 mental structure. It was never more true than 
 to-day that knowledge is power. And never be- 
 fore was so much new knowledge being presented 
 for our edification each day ; for this is the period 
 of greatest scientific activity that the world has 
 ever known. 
 
 Bear in mind, then, that every hour you give to 
 desultory thought and vapid conversation, or to 
 trivial reading is an hour not merely wasted but 
 devoted to the permanent damage of your brain ; 
 because you are preserving what may be likened 
 to a jangling, discordant noise record, graven on 
 a phonograph cylinder that might have received 
 instead a record of fine music. 
 
 And you have no excuse. For in these days 
 good books are cheap and good magazines still 
 cheaper. There are free lecture courses and free 
 libraries everywhere. So regardless of your cir- 
 cumstances it is matter of choice with you whether
 
 148 Adding Years to Your Life 
 
 yon will fill your brain cells with records of useful 
 knowledge or make it a lumber room for an ac- 
 cumulation of trash; or, to hold to our figure, 
 whether you will store your mental phonograph 
 with the vibrations, let us say, of splendid operas 
 and symphonies, or with rag-time; with Caruso 
 records or with ribald songs of the underworld. 
 
 The Brain Records Are Permanent 
 
 It is obvious that after middle life most of us 
 have very few experiences that could be called 
 altogether new. 
 
 In the main our life routine is but a matter of 
 perpetual repetition of old experiences. Our 
 brains become grooved and channeled with oft- 
 repeated messages which finally come to be trans- 
 mitted so automatically that they tend to slip into 
 the domain of the unconscious and subconscious. 
 We perform a hundred and one tasks practically 
 without giving them a thought, though they were 
 difficult and even painful when they were first per- 
 formed. 
 
 Our ideas and ideals become fixed and estab- 
 lished nearly or quite beyond alteration. We have 
 settled likes and dislikes; our vocabularies be- 
 come limited to certain sets of words; and our 
 phraseology takes on unvarying and readily recog- 
 nizable forms. 
 
 In a way, most of us by middle life have become 
 fossilized automata. 
 
 It is familiar experience that vastly the larger
 
 Are Your Nerves in Tune? 149 
 
 number of impressions that come to us lapse 
 presently into the realm of the unconscious. But, 
 though unremembered, they nevertheless are per- 
 manently recorded in the brain. Dr. Frederick 
 Peterson, of New York, has published an interest- 
 ing account of tests made by him in association 
 with Dr. Yung at Zurich, Switzerland, in which 
 methods were found of getting at the unconscious 
 and subconscious mentality by merely pronounc- 
 ing various words and asking the patient to pro- 
 nounce in turn the first words that come into his 
 mind in response. 
 
 By such a test it is possible to show strange 
 linkage of ideas which the psychologist can inter- 
 pret in the light of the patient's early experiences, 
 proving that the brain cells permanently retain 
 records of events, even of the most trivial charac- 
 ter, of which the conscious individual has no 
 definite recollection. 
 
 Of similar import is the work of the Viennese 
 physician Freud, whose theories of the interpreta- 
 tion of dreams have gained such wide vogue in 
 recent years. He shows how full of meaning are 
 the records that come into the foreground in the 
 dream. Daytime experiences to which you gave 
 no thought may be so deep-graven in the brain as 
 to make the substance of haunting dreams, linked 
 with experiences of childhood that had been no 
 part of conscious mentality for perhaps a score 
 of years. 
 
 Such interpretation of dreams as the Freudians 
 make goes far to prove that each and every experi-
 
 150 Adding Years to Your Life 
 
 ence of our lives each sensation, each thought, 
 each correlation of ideas; every hope, desire, ex- 
 pectation, or emotion leaves a permanent record 
 in the mystic galaxies of brain cells. 
 
 Bear all this in mind as you are choosing your 
 reading, your associates, your topics of thought 
 and conversation. Remember that your mind at 
 maturity will be largely what you have chosen to 
 make it. " As a man thinketh, so is he," is the 
 most literally true of maxims. 
 
 And remember, too, how imperishable is the 
 record. Hour by hour of your life you are carving 
 these tell-tale lines in your brain ; and you can no 
 more transform them all of a sudden than you can 
 change your phonograph record from ragtime to 
 symphony by merely wishing it changed. 
 
 Building a New Personality 
 
 But can the brain records be changed at all! 
 This is the most important of questions ; back of 
 it lies the whole problem of education. 
 
 In point of fact, it is possible that no individual 
 record can be changed except to make it more in- 
 tense, or to allow it to become enfeebled through 
 lack of repetition. But as all important experi- 
 ences are complex, it is possible to pile up new 
 records in the brain of such character as will tend 
 to subordinate unfortunate earlier records, and 
 finally to make them relatively inconsequential. 
 
 So there is always the cheering possibility of 
 bringing new sets of cells into action, of making
 
 Are Your Nerves in Tune? 151 
 
 good records to supplement and subordinate the 
 bad ones, and thus in effect changing the charac- 
 ter of the brain action and of the personality asso- 
 ciated with it. 
 
 In reality, each of us is thus building a new per- 
 sonality on the foundation of the old one, day by 
 day. 
 
 Remember always this underlying principle: 
 doing a thing once good thing or bad thing 
 makes it easier to do that thing again. This is the 
 basal principle of nervous action. Start a grooved 
 channel of nervous impulses, and the tendency is 
 to repeat. It is easier for future impulses to 
 travel the old track than to break into new chan- 
 nels. 
 
 In reality the chief function of volition is to in- 
 hibit the responsive action of the brain cells which 
 would tend to result in sending nervous impulses 
 along old channels ; and through such inhibition to 
 make possible the opening up of new channels. 
 
 Remember that * * will power ' ' is largely power 
 to prevent action. A trained will is one that holds 
 the brain cells in leash, as it were, and determines 
 that the nervous impulses sent out shall not al- 
 ways take the old familiar line of least resistance. 
 All mental discipline may be summed up in the 
 development of this inhibitory power of the will ; 
 for in the last analysis this is what we mean by 
 mental training. 
 
 But all that has been said emphasizes the lesson 
 that the right kind of training of the brain cells 
 cannot be begun too early. The fewer bad habits
 
 152 Adding Years to Your Life 
 
 of nervous action, the less need there will be for 
 unlearning and the easier will be the task of dis- 
 cipline. But however well the task may have been 
 begun, the habit of training the brain cells to bet- 
 ter and better lines of action is one that should be 
 continued throughout life. 
 
 The test of conscious life itself is to be able to 
 send out nerve stimuli from the brain. The test 
 of youth regardless of years is to be able to set 
 up new channels of innervation so grooved that 
 they act automatically in the best way. And noth- 
 ing else in life is so much worth while as to have 
 a brain trained to act with the fullest measure of 
 efficiency to the full limit of its best capacities. 
 
 A brain thus trained will know how to select the 
 right vocation, and how rationally to conserve its 
 energies. There is little danger that nerves con- 
 trolled by such a brain will ever get the better of 
 you and ' ' grow on the outside. ' ' They will always 
 keep their place, and keep " in tune."
 
 VI 
 
 Can You See Straight? 
 
 in\0 you see things as they are? Do things look 
 * * to you as they look to others? Do you know 
 that thousands of people have abnormal vision, 
 and yet are not aware that they cannot see as 
 others see? Eye-strain may cause headache, men- 
 tal exhaustion, neuralgia, St. Vitus' dance, and 
 even epilepsy. 
 
 Thousands of people suffer from one or another 
 of these maladies, due to eye-strain, and do not 
 know the cause. Do you know whether you are 
 subject to brain fag in this way? 
 
 In particular do you know whether your chil- 
 dren have eye defects that are making their stud- 
 ies difficult and threatening them with permanent 
 injury? There are hundreds of thousands of chil- 
 dren thus affected. You should know not guess 
 whether or not yours are among them. 
 
 Again, even if your eyes and the eyes of your 
 children are normal, do you know how to keep 
 them normal? If not, you should find out. Eyes 
 are too valuable an asset to be neglected. This 
 chapter will tell you how to care for them. 
 
 . Eye Surgery 
 
 Not long ago I spent an afternoon in the oper- 
 ating room of the New York Eye and Ear In- 
 
 153
 
 154 Adding Years to Your Life 
 
 firmary. There I saw Dr. John M. Wheeler per- 
 form a series of delicate and interesting opera- 
 tions. 
 
 In one case the eyeball was cut open and a piece 
 of iris snipped out ; in another the lens of the eye 
 itself was extracted. An eyeball was cut out en- 
 tirely and its place supplied with a bit of fatty 
 tissue cut from the patient's leg, not to restore 
 vision, of course, but to prevent the socket of the 
 eye from sinking. 
 
 In another case an eye that had too much in- 
 ternal pressure was drilled into with a tiny 
 trephine. From yet another eye a chip of steel 
 from a chisel was extracted with a gigantic mag- 
 net. 
 
 In yet other cases the muscles of the eye were 
 cut to cure a squint. 
 
 And, most curious of all, perhaps, an eye that 
 was opaque at the " sight " was tattoed with In- 
 dia ink and made much worse for the moment in 
 order that later it might be restored to vision. 
 
 It was all very interesting. But what sank 
 deepest in my mind was a chance remark of one 
 of the physician's who watched the operations, as 
 we came away from the clinic. " It is a wonder- 
 ful thing," he said, " to be able to restore vision 
 as the modern ophthalmic surgeon does ; but most 
 of these operations would have been uncalled for 
 if the patients had taken better care of their eyes, 
 particularly in childhood. A good share of the 
 conditions that make the operations necessary are 
 due directly or indirectly to slight errors of re-
 
 Can You See Straight? 155 
 
 fraction that could easily have been remedied at 
 first with glasses.'* 
 
 " Errors of refraction." That is the phrase 
 that is always on the lips of the eye specialist. 
 Being interpreted, it means merely " eyes out of 
 focus." We all know what that means nowadays, 
 because we all take pictures with the camera and 
 so are familiar with the blurred image of an out- 
 of-focus picture. And the eye is just a living 
 camera; the pictures on its sensitized film (the 
 retina) may be sharply defined or they may be 
 blurred. And you do not like a blurred picture 
 any better in the eye than you like it on the photo- 
 graphic plate ; so the eye that receives this blurred 
 image strives constantly to get it in focus. If it 
 has difficulty in doing so, there is what the special- 
 ist calls * * an error of refraction. ' ' 
 
 Suppose, for example, that the globes of your 
 eyes are a trifle shorter than they should be. Then 
 the lens of your eye, which bends the rays of light 
 and brings them together precisely as does the 
 lens of a camera, will have a focal point lying a 
 little behind the retina, and you will always be 
 striving, consciously or unconsciously, to adjust 
 the focusing apparatus. This will mean a con- 
 stant and abnormal straining of the muscles of the 
 eye. If the shape of your eyeball is but slightly 
 abnormal, the focusing apparatus may overcome 
 the defect, and you may have sharp vision. But 
 the correction is made at the expense of an un- 
 usual and fatiguing effort. 
 
 It is a very wonderful mechanism, this focusing
 
 156 Adding Years to Your Life 
 
 apparatus in your eye ; a very puzzling mechanism 
 when we reflect that the normal eye is a camera of 
 universal focus. With the photographic camera, 
 you change the focus by lengthening or contract- 
 ing the bellows, thus carrying the lens farther 
 from the sensitized plate or bringing it nearer ac- 
 cordingly as you wish to photograph nearby or 
 distant objects. But with the human eye no such 
 change is possible. The lens lies back of the dia- 
 phragm (called the iris) precisely as in the photo- 
 graphic camera, but its position is fixed ; it cannot 
 be brought nearer the retina. 
 
 Yet the eye is at once telescope and microscope, 
 focusing far objects and near in seeming defiance 
 of the laws of optics. 
 
 This effect is accomplished by one of the most 
 ingenious mechanisms that nature ever devised. 
 
 The Crystalline Lens 
 
 The gist of the matter is this : the lens of the 
 eye, although called " crystalline," is not a rigid 
 body, like the lens of a telescope or microscope ; it 
 is more like a bit of very firm gelatine. 
 
 It is held in position by an elastic capsule at- 
 tached at the sides of the eyeball. Similarly at- 
 tached to the circumference of the eyeball, just 
 back of the iris, is a circle of muscular tissue. 
 When this muscle contracts, it tends to constrict 
 the iris and it relaxes the capsule that encloses the 
 crystalline lens. The resilient lens, in virtue of 
 its elasticity, assumes a thicker form, and a more
 
 Can You See Straight? 157 
 
 convex anterior surface. And this is precisely the 
 change that is necessary to refract the rays of 
 light coming from a nearby object and bring them 
 to a focus on the retina. 
 
 When your attention is directed to such a near- 
 by object, the series of changes just outlined takes 
 place within the eye, and the result is equivalent 
 to an extension of the bellows of the camera. 
 
 Contrariwise, when the eye is directed to a dis- 
 tant object, the ciliary muscle relaxes, the iris ex- 
 pands, and the capsule of the crystalline lens, 
 freed from muscular tension, exerts its con- 
 strictive force on the lens, flattening that essen- 
 tial structure. This changes the refractive power 
 of the lens in precisely the way necessary for fo- 
 calization of light coming in almost parallel beams 
 from the distant object. 
 
 Primitive Eyes 
 
 It is obvious that until some such mechanism as 
 that just described was evolved, light could not be 
 brought to a focus, and the organism would be 
 aware only in a vague and general way of the na- 
 ture of the objects from which the light came. 
 Without this perfected eye, creatures could de- 
 velop a considerable degree of intelligence, as 
 such insects as the bee and ant amply prove. Yet }< 
 we may well doubt whether without a universal- 
 focus eye any being could ever have come above 
 the plane of intelligence of, let us say, the fish. 
 
 Only a creature having vivid impressions of its
 
 158 Adding Years to Your Life 
 
 surroundings far and near, such as vision alone 
 can give, could get clear notions of the world in 
 which we live ; and such sensations are the build- 
 ing-stones of the mind. 
 
 The bee and the ant see only a little way ; they 
 depend on scent for their knowledge of distant ob- 
 jects, unless, indeed, they perceive vibrations of 
 which we know nothing; and the range of im- 
 pressions supplied by odors is at best very 
 limited. 
 
 The vibrations of sound provide information of 
 a more comprehensive kind, once ears were 
 evolved to receive them; yet even the records of 
 hearing are relatively vague and unlocalized as 
 contrasted with the records of vision. The range 
 of sound waves is also limited. Sound covers 
 only 1,040 feet per second, while light traverses 
 186,000 miles of space in the same time. 
 
 Sound requires a substantial medium in air or 
 liquid or solid ; light voyages in the ether. 
 
 Consider how largely your impressions of the 
 world are visual impressions. How utterly 
 changed the world would seem if you had no men- 
 tal picture of things seen: no conception of light 
 or of color. Your mind would be a blank as to 
 entire fields of knowledge. You would have only 
 vague notions of distant objects; no knowledge of 
 form or size or shape or texture except of such 
 objects as you could actually touch. Yours would 
 be a sterile and barren world dark and picture- 
 less as contrasted with the world of light and 
 color and form and distance.
 
 Can You See Straight? 159 
 
 Such must have been the world of all creatures 
 before eyes were evolved. But eyes came early in 
 the scheme of evolution. 
 
 The Eyes of Lower Animals 
 
 The earliest plan for making possible both near 
 and far vision was, however, somewhat more 
 primitive than the one finally evolved. In the eye 
 of the fish the crystalline lens is spherical, and 
 when the eye is at rest the focus is on nearby ob- 
 jects, instead of on distant ones as in the case of 
 man and the higher animals. If the fish wishes to 
 scrutinize distant objects, its spherical lens is 
 moved backward in the liquid of the eyeball, thus 
 changing the focus precisely as it is changed by 
 contracting the bellows of a camera. But the 
 movement is limited, and the arrangement cannot 
 give anything like so wide a range of focusing 
 power as is possible with the perfected lens of 
 mammals and man. 
 
 In the amphibia, of which the frog is a familiar 
 representative, the eye is still fish-like, in that fo- 
 cusing is done by shifting of the lens. The ciliary 
 muscle first becomes fully developed, and assumes 
 its function of changing the shape of lens, in the 
 eyes of reptiles, which are the next higher order 
 of creatures in the zoological scale. 
 
 The eyes of all mammals are identical with 
 those of man in the method of manipulation of the 
 focusing apparatus ; that is to say, focusing is ac- 
 complished by changing the shape and not the
 
 160 Adding Years to Your Life 
 
 position of the lens. But, whereas the lens itself 
 is flattened, like that of man, in diurnal animals, 
 it is spherical in nocturnal and aquatic animals. 
 In the nature of the case, animals that prowl by 
 night, and those that inhabit the water, have a 
 relatively restricted range of vision. Their eyes 
 must for the most part be used in viewing objects 
 near at hand, so doubtless it is to their advantage 
 to have a crystalline lens that is more of a micro- 
 scope than a telescope. 
 
 Probably it would be to man 's advantage, under 
 the conditions of modern civilization, if his lens 
 could revert somewhat toward the spherical type, 
 since so many people nowadays are obliged to 
 wear convex lenses. 
 
 Binocular Vision 
 
 The building up of brain records and mental 
 impressions from sensations received through the 
 eyes, on the part of our remote ancestors, must 
 have become more and more precise as the eye was 
 perfected, and increasingly varied as the evolving 
 races found new environments and were subjected 
 to new conditions. Swiftly moving creatures, par- 
 ticularly those that hunt or are hunted, obviously 
 need sharp vision for objects at all distances: 
 their lives depend upon it. 
 
 And if you have been much in the open, you will 
 not question that birds and animals in general 
 have good eyes. 
 
 There is one really important difference, how-
 
 Can You See Straight? 161 
 
 ever, between the type of vision of birds and all 
 lower orders of mammals and the vision of men. 
 If you look at a bird you will see that its eyes are 
 set on opposite sides of the head, and hence must 
 receive totally different images at a given moment. 
 A bird cannot look at any object with both eyes 
 at once. The same thing is true, in greater or less 
 measure, of most mammals. 
 
 It is only creatures of the monkey tribe that 
 share with man the capacity to fix both eyes on 
 the same object and bring the two images into 
 such harmony that they are registered in the brain 
 as a single image. 
 
 This so-called binocular vision is not without 
 its disadvantages. The eyes of a bird sweep all 
 horizons at a glance, and may make it aware of 
 the approach of an enemy from any direction. And 
 for a creature subject to attack on all sides this 
 is obviously an advantage. Seeing in all direc- 
 tions is less important when the bird is one that 
 habitually hunts and is not itself hunted; and so 
 we find that in the case of eagles and hawks, and 
 even more conspicuously in the case of owls, the 
 eyes tend to assume a forward location in the 
 head, limiting somewhat the range of vision but 
 making it possible to see the same object with both 
 eyes at the same time, not to see it clearly in a 
 single image as the human eyes do, but neverthe- 
 less to gain such a double view as will give a clear 
 notion of the distance of the object. 
 
 This is obviously important for such creatures 
 as the hawk and the owl, which must be able to
 
 1 62 Adding Years to Your Life 
 
 pounce upon their prey and strike out with their 
 talons at precisely the right moment in seizing it. 
 
 It is for this reason, doubtless, that the eyes 
 of predacious mammals are placed relatively near 
 together in the head, to permit binocular vision ; 
 whereas the eyes of creatures that are hunted are 
 placed at the sides of the head, to give wide vision 
 at the expense of concentration. 
 
 Contrast the face of a cat with that of a mouse, 
 by way of illustration. For the cat, it is impor- 
 tant to be able to locate the precise distance of 
 its prey as it springs ; but for the mouse what is 
 chiefly important is to be able to discover an 
 enemy in any direction rather than to gauge the 
 precise distance of the enemy. 
 
 What Double Vision Accomplishes 
 
 The advantages of binocular vision, however, 
 for a creature of developed intelligence, and in 
 particular for one whose habits bring it in contact 
 with new surroundings from time to time, are 
 very striking. 
 
 Not only the distance of objects but their form 
 is revealed by binocular vision as it could not be 
 when the view is that of a single eye. 
 
 It is obvious that your two eyes, when focused 
 on a given object fairly near at hand, do not re- 
 ceive precisely the same image unless the object 
 focused is a flat surface. If you look at a book 
 lying on the table in front of you in such position 
 that you see the back and one side and the end in
 
 Can You See Straight? 163 
 
 perspective, you gain a perfectly clear notion of 
 that book as a structure having three dimensions, 
 and the reason you do so is because the right eye 
 gets a slightly different view of the book from that 
 gained by the left eye, a fact that you may read- 
 ily verify by closing first one and then the other. 
 Otherwise stated, your vision, when you look with 
 both eyes, is stereoscopic. 
 
 You are therefore constantly gaming impres- 
 sions as to the precise form of objects, and these 
 impressions are stored away in your brain and 
 form part of the sub-structure of an important 
 aspect of your mental development. 
 
 At the same time that your eyes give you defi- 
 nite impressions as to the shape of objects, they 
 give you precise impressions also as to the dis- 
 tance of any object on which you focus, because 
 your two eyes must be made to turn toward each 
 other in order to focus on a nearby object. You 
 are not ordinarily conscious of this effort, yet it 
 is registered in your brain, and the difference in 
 effort required to focus on nearby and on far-off 
 objects is interpreted as determining the actual 
 distance of the object, even though it be located 
 on a plane surface. 
 
 You can, for example, judge with a good degree 
 of accuracy the distance of a printed page held 
 before your eyes, provided you look with both 
 eyes. But you can judge much less accurately if 
 you look with a single eye. 
 
 But, of course, there is no gain without the pos- 
 sibility of attendant loss, and binocular vision
 
 164 Adding Years to Your Life 
 
 adds some complications to the visual apparatus 
 that give opportunity for maladjustment. If, for 
 example, the muscles that control the movements 
 of the eyeballs fail to work in harmony, the eyes 
 will tend to act independently, and while this 
 would answer very well for a bird or a dog, it will 
 not do at all for a man, and the condition must be 
 remedied by surgical procedure. 
 
 Again, it is essential with binocular vision that 
 the two eyes shall focus exactly alike ; yet in point 
 of fact no two eyes ever are identical. Usually 
 the difference is not so great that it is noticed, but 
 very often there is enough difference to cause con- 
 stant, even though unrecognized, eye-strain. 
 
 The two eyes then try constantly to adjust them- 
 selves to each other, or else one gives up the task, 
 and leaves all the work for its stronger or less 
 aberrant fellow. 
 
 Eyes Out of Focus 
 
 The aberrations that disturb the focus and cause 
 abnormal vision may depend on anomalies of the 
 eyeball itself, or of that wonderful mechanism, the 
 crystalline lens. 
 
 Thus, the lens may be too thick or too thin for 
 the eyeball in which it is adjusted, in which case 
 its possessor is " near-sighted " or " far- 
 sighted." Or it may be asymmetrical, in which 
 case the image it casts is distorted and its pos- 
 sessor suffers from lenticular astigmatism. The 
 same defects of vision may result, as we have seen,
 
 Can You See Straight? 165 
 
 if the ball of the eye itself is too short or too long 
 or asymmetrical. In either case, the rays of light 
 will not all focus properly, even if some of them 
 do. 
 
 Yet again, the lens may come to lack resiliency ; 
 it may harden and lose its responsiveness. This 
 is very likely to occur with advancing age; and 
 everybody knows that elderly people often have 
 good distant vision but are unable to focus on 
 nearby objects. Artificial lenses easily remedy 
 these defects. But a far more serious and for- 
 tunately also a far less common concomitant of 
 old age may come in the form of a clouding of the 
 lens, developing finally a milky opacity that shuts 
 out the light altogether. 
 
 This condition is called cataract. It causes par- 
 tial or total blindness, that is incurable except by 
 removal of the lens itself. Fortunately, however, 
 this is an operation that involves no difficulties for 
 the trained ophthalmic surgeon. 
 
 You may cut off the antenna that bears the eye 
 of a crustacean say a crab or lobster and a new 
 eye will grow to take the place of the old one. But 
 the specialized tissues of higher animals are not 
 thus restored, and the lens once gone is gone for- 
 ever. The transparent fluids of the eye will take 
 its place, but its function of refracting light and 
 bringing it to a focus on the retina must there- 
 after be performed by heavy convex glasses. With 
 the aid of these, however, a good degree of vision 
 may be given to eyes that are totally blind before 
 the removal of the cataract.
 
 166 AdHing Years to Your Life 
 
 Eye Defects that We Nearly All Have 
 
 These surgical cases, however, do not so much 
 concern you as do the more usual defects of re- 
 fraction already referred to. These, under con- 
 ditions of modern life, are all but universal. 
 
 The eye that is called upon to focus on fine 
 print, page after page, is subject to a strain that 
 in a sense is abnormal ; for the ancestral eye was 
 chiefly employed in long-distance work, as became 
 the eye of the fisher, the hunter, and the husband- 
 man. And the structure of such an organ cannot 
 be radically changed in a few hundred genera- 
 tions. Beading, as applied to people in general, 
 is a very modern habit. Only two or three gen- 
 erations ago half the women of England, and a 
 large number of the men, were obliged to make 
 their mark in witnessing their marriage contracts. 
 Universal literacy, applied to the masses in gen- 
 eral, is a social development of the nineteenth 
 century. 
 
 So it is almost a matter of course that the mod- 
 ern eye yields habitually to the abnormal strain, 
 and cries out for aid. 
 
 If aid is not forthcoming, messages of distress 
 are sent to the brain that are interpreted as head- 
 aches, irritability of temper, and the like. Mean- 
 time, the eyes themselves become inflamed, or 
 through the excessive muscular action required in 
 focusing they assume a permanent condition of 
 " squint," which the specialist terms strabismus. 
 Short of this, the strain may produce weariness of
 
 Can You See Straight? 167 
 
 brain, and the defects of vision may be instrumen- 
 tal in retarding the progress of the child, when the 
 very existence of the defect is unsuspected. 
 
 Thousands of children pore over their books 
 without ever being able to see clearly a single let- 
 ter; they themselves quite unconscious that their 
 vision is not normal, and their parents and teach- 
 ers equally oblivious. Such children carry a need- 
 less burden. 
 
 Take steps to find out if your child is of this 
 number. If you have reason to suspect abnormal- 
 ity of vision, have the matter decided by a com- 
 petent physician; not by a spectacle vendor or op- 
 tician whose legitimate business is merely to make 
 glasses on prescription, not to write the pre- 
 scription itself. 
 
 For those who cannot afford to pay a physician, 
 there are clinics where the most skilful attention 
 is given free of charge. 
 
 How the Tests Are Made 
 
 When the oculist tests your eyes, he places you 
 with your back to a light and reflects the light 
 through your pupil with a little concave mirror 
 called an ophthalmoscope. 
 
 This instrument was invented by the celebrated 
 German physicist, Helmholtz. Its user looks 
 through a. small hole in the centre of the mirror, 
 a simple but ingenious device that enables him to 
 look into the depths of your eye and see the sur- 
 face of the retina as if it were on the outside.
 
 1 68 Adding Years to Your Life 
 
 Lenses of different curvature adjusted in the mir- 
 ror enable the user to determine the curve of the 
 retina and to detect any departure from the nor- 
 mal. It is possible also with the ophthalmoscope 
 to observe the condition of the blood vessels in the 
 retina, and thus to detect other abnormalities than 
 those having to do with refraction. 
 
 After the test with the ophthalmoscope has 
 given a fairly accurate idea as to the errors of re- 
 fraction, further tests are made with lenses of 
 different curvature, in which your own observa- 
 tion supplements the results of the ophthalmo- 
 scopic examination. 
 
 With young people in particular, the action of 
 the ciliary muscles is so persistent and the con- 
 striction of the iris so marked under the influ- 
 ence of light that it is necessary to use atropin or 
 its modern derivative homatropin to relax the 
 muscle and dilate the pupil. 
 
 Under these conditions the crystalline lens as- 
 sumes what may be considered its normal shape, 
 and the large aperture of the iris makes full view 
 of the retina possible. As the muscle that nor- 
 mally changes the shape of the lens is temporarily 
 paralyzed, the tests will show the refractive con- 
 ditions, uninfluenced by any voluntary effort on 
 the part of the patient. It is thus possible to 
 make a more accurate and reliable test of the 
 actual conditions of refraction than could be made 
 while the ciliary muscle has normal action and is 
 persistently trying to focus. 
 
 The prescription which the oculist writes seems
 
 Can You See Straight? 169 
 
 mystifying to the average layman. Its " 0. D." 
 and " 0. S.," however, imply nothing more than 
 " right eye " and " left eye "; and the mysteries 
 of its formulas may be summed up in the statement 
 that the lenses for which it calls are either plainly 
 spherical, concave or convex (their power desig- 
 nated in " diopters ") or are ground on a cylin- 
 drical foundation, the axis of which is so adjusted 
 as to correct the asymmetry of the cornea or lens 
 or eyeball that causes the condition known as 
 astigmatism. 
 
 A large number of individuals suffer from this 
 condition, and hence have blurred vision, without 
 ever recognizing their defect. 
 
 It has been suggested that a modern school of 
 impressionistic painters owes its origin to the fact 
 that the master suffered from astigmatic vision, 
 and saw objects at a distance less clearly than 
 people of normal vision see them. 
 
 Be that as it may, it is obviously desirable that 
 you and I should see objects about us as they are, 
 or at least as other people see them. Clear vision 
 is at a premium in many callings ; and, aside from 
 that, the relief and comfort that people with astig- 
 matic eyes receive from properly gauged glasses 
 is something to which hundreds of thousands of 
 individuals could testify. 
 
 Taking Care of the Eyes 
 
 As a rule, if your eye is astigmatic you must 
 wear the corrective lenses at all times. For the
 
 170 Adding Years to Your Life 
 
 eye once distorted in shape is seldom restored to 
 normality. But you should clearly understand 
 that if your eyes had been properly cared for from 
 childhood they probably now would not have be- 
 come astigmatic. Like most other permanent eye- 
 defects, this is usually traceable to overuse or in- 
 correct use under unfavorable conditions. 
 
 The eye of the child is usually normal in shape 
 and function. If properly cared for it will usually 
 remain normal. 
 
 So it becomes an important question for each of 
 us as to what constitutes the right treatment of 
 the normal eye. 
 
 In general, rules for hygiene of the normal eye 
 are very simple and easy to follow out. It is 
 scarcely more than the reiteration of a truism to 
 say that you should not read fine print persist- 
 ently, or focus on minute objects of any kind, with- 
 out periods of rest. Even in reading ordinary 
 print, you should glance up from time to time, and 
 give the ciliary muscles a moment of relaxation by 
 casually looking at some distant object or throw- 
 ing the eyes altogether out of focus. 
 
 You cannot hold your arm extended for even a 
 few minutes without its muscles becoming utterly 
 exhausted. There is no reason why you should 
 expect the muscles of your eyes to be tireless. 
 
 It is very important, too, that the eye should 
 not be subjected to undue strain through reading 
 a badly-lighted page. The light, on the other 
 hand, should not be too intense. It should pref- 
 erably come from behind the head or from the
 
 Can You See Straight? 171 
 
 side, so that the rays are not directly reflected into 
 the eye from a brilliant electric light or Wels- 
 bach burner, but come rather in diffused rays. 
 
 In reading at night it is desirable to have the 
 room in general fairly dark, so that the iris may 
 be well dilated. The reading light need not then 
 be too intense, if placed near the page it illumi- 
 nates. 
 
 Under these conditions it is possible to read for 
 hours with less strain on the eyes than would re- 
 sult from a few minutes of reading with a light 
 that is badly placed or with one that is either too 
 brilliant or too dull. 
 
 Should the eyes show a tendency to irritation or 
 inflammation, the use of a saturated solution of 
 boric acid, applied with the ordinary eye-cup, will 
 almost always be of service; but such a tentative 
 measure should not of course take the place of a 
 radical correction of any error of refraction by 
 the use of proper glasses. 
 
 Occupation and Eye-Strain 
 
 Of course, the character of your occupation may 
 make it almost impossible for you to avoid over- 
 use or abnormal use of your eyes. 
 
 Dr. George M. Gould, whose life-long exposition 
 of the evils that result from eye-strain is well 
 known, gave a list of occupations with reference 
 to their average effect on the eyes in a paper be- 
 fore the International Congress of Hygiene at 
 Washington. He divided the occupations into five
 
 173 Adding Years to Your Life 
 
 large groups, aggregating 114 individual call- 
 ings. 
 
 The first group comprised largely persons lead- 
 ing outdoor lives, from hunters and trappers, lum- 
 bermen, seamen, farmers, and common laborers to 
 gardeners, hod-carriers, quarrymen, and locomo- 
 tive engineers. Only from one to twenty per cent 
 of the persons in these occupations, according to 
 his estimate, have diseases due to eye-strain. 
 
 The second group, including railway conductors, 
 outside painters, carpenters, merchants and sales- 
 men among others, shows twenty to forty per cent 
 of cases with eye-strain diseases. 
 
 In successive groups, the percentage rises, al- 
 ways with the inclusion of occupations requiring 
 more and more constant use of the eyes, particu- 
 larly for nearby work, until in the fifth group, be- 
 ginning with students in seminaries and colleges 
 and with clergymen, lawyers, and bank clerks, and 
 ending with type-setters, type-cutters, miniature 
 painters, photograph retouchers, and etchers, the 
 ratio of defects is given as from eighty to one 
 hundred per cent. 
 
 In other words, persons whose occupation re- 
 quires almost incessant focusing of the eyes on 
 nearby objects, and particularly small objects, de- 
 velop abnormalities of vision almost as a matter of 
 course. 
 
 Moreover, the results of eye-strain thus intro- 
 duced are not at all confined to abnormalities of 
 the eyes themselves. Dr. Gould believes that con- 
 stant straining of the eyes, particularly without
 
 Can You See Straight? 173 
 
 properly adjusted spectacles, is the main cause of 
 the observed fact that telephone girls suffer from 
 a great variety of illnesses and usually break down 
 altogether after two or three years of service. 
 
 The report of a Royal Commissioner of Canada 
 as to the maladies resulting from telephone oper- 
 ating gives a list of defects that covers almost a 
 page of fine print. " Nervous debility, wearing 
 down of the nervous system," " headache from 
 looking at the holes," " inability to sleep," 
 " fainting," and " nervous prostration and nerv- 
 ous breakdown ' ' are among the conditions listed ; 
 and it is declared that " after five years the girl 
 will be disqualified to become a wife and mother ' ' ; 
 and the prediction is made that " on future gen- 
 erations the effect will be epilepsy and all sorts 
 of nervous diseases." 
 
 In Dr. Gould's view these untoward results, and 
 similar ones reported elsewhere, are very largely 
 due to a single cause. 
 
 " The disorders most frequently mentioned," 
 he says, " and most emphasized among the tele- 
 phonists are nervous affections, digestive disor- 
 ders, anemia, nervousness, neurasthenia, nervous 
 debility, migrain, headaches, vertigo, palpitation, 
 and so on, precisely those I have found in thou- 
 sands of cases and for twenty or more years have 
 demonstrated to be due to eye-strain." 
 
 Not all authorities are prepared to go quite as 
 far as does Dr. Gould in ascribing the observed 
 maladies exclusively to eye-strain, but no one com- 
 petent to judge will doubt that eye-strain is at
 
 174 Adding Years to Your Life 
 
 least an important contributory factor in a very 
 large proportion of cases. Nor can it be ques- 
 tioned that it is in the highest degree important, 
 not merely for telephone operators but for the fol- 
 lowers of every line of work that requires constant 
 exacting use of the eyes, that their eyes be care- 
 fully tested and any errors of refraction fully 
 compensated with proper glasses. 
 
 Guarding the Child's Eyes 
 
 But the most important thing of all, of course, 
 is to safeguard the eyes of children. 
 
 To begin at the beginning you should under- 
 stand that abnormal conditions of the eye are 
 peculiarly likely to be inherited. The very com- 
 mon condition that leads to shortsightedness is 
 partially due to a thinness or a lack of toughness 
 of fibre of the structure of the eyeball itself. The 
 muscles tugging constantly at the eyeball, par- 
 ticularly in focusing on nearby objects, exert such 
 a constricting force as gradually to lengthen the 
 eyeball, making it more or less egg-shaped; the 
 result being that the rays of light are focused in 
 front of the retina. Thus it becomes necessary 
 to bring objects very near to the eye in order to 
 see them clearly, and the straining incident to fo- 
 cusing at close range aggravates the difficulty, so 
 that shortsightedness is likely to be progressive. 
 
 The condition of the eyeball that leads to this 
 result is likely to be transmitted to the offspring. 
 
 So if either parent of a child is nearsighted, the
 
 Can You See Straight? 175 
 
 eyes of the child should be given careful attention. 
 The condition of nearsightedness will probably 
 not develop until the child is six or eight years old ; 
 but the probabilities of its development should be 
 borne in mind from infancy, and efforts made to 
 obviate this unfortunate result. 
 
 To that end, the child should be given large ob- 
 jects to play with, even in the nursery. It should 
 have its letters taught by forming them with 
 blocks of wood, rather than by the use of a book. 
 Even the scanning of picture books should be dis- 
 couraged, and in general the child should be pre- 
 vented from scrutinizing habitually small objects 
 or nearby objects of any kind. It should not be 
 permitted, for example, to draw pictures, to sew, 
 or to thread beads, or to engage in any other occu- 
 pation or diversion that necessitates near vision. 
 
 Dr. Ernest Clark, the London specialist, urges 
 that no child having the hereditary tendency to 
 shortsightedness should be allowed to learn to 
 write or draw until it is at least seven years old. 
 
 Dr. Gould, in the paper already quoted, declares 
 that shortsightedness is a malady that is almost 
 tragical in its importance to thousands of its vic- 
 tims. Where the defect of aberration is pro- 
 nounced, he says, any swift, safe, or accurate sport 
 or bodily activity, except swimming, is impos- 
 sible. The shortsighted person never dares to 
 run, and all motions must be slow, indefinite, and 
 cautious. 
 
 Yet all this, Dr. Gould emphatically declares 
 is needless. " The origin of the condition of the
 
 176 Adding Years to Your Life 
 
 eye that causes shortsightedness is known and 
 its preventableness certain. It is called simply 
 and solely by uncorrected, by overcorrected, or 
 by miscorrected hyperopic astigmatism," that 
 is to say, an eyeball that in the beginning is 
 slightly too short and asymmetrical and which 
 therefore has an error of refraction that the eye 
 strains constantly to correct. 
 
 And Dr. Gould adds : ' ' There need not be a 
 single shortsighted individual in the civilized 
 world and there will not be one when the world 
 becomes genuinely civilized." 
 
 Small Defects Are Most Dangerous 
 
 After citing such testimony, it is almost super- 
 fluous to add that, regardless of hereditary tenden- 
 cies, you should make the most painstaking effort 
 to ascertain whether your child has any error of 
 refraction. 
 
 Above all it is important to realize that even 
 slight errors, necessitating a constant eye-strain, 
 may lead to most disastrous results. Indeed, it 
 is the rather paradoxical fact that small errors of 
 refraction are the ones most likely to cause eye- 
 strain with its attendant evils. If the refractive 
 error is large the eye does not try to overcome it, 
 but if it is slight there is constant straining, 
 usually unknown to the child himself, and the wear 
 and tear not only on the eye itself, but on the 
 brain centres is almost sure to produce permanent 
 injury. This may take the form of inflammation
 
 Can You See Straight? 177 
 
 of the eyes, leading perhaps to granular lids or 
 even to incurable maladies of the interior of the 
 eye, such as inflammation of the iris, increase of 
 the fluid contents of the eyeball, or the condition 
 called cataract. 
 
 In other cases the symptoms may not focalize on 
 the eye, but there may be severe neuralgia, con- 
 vulsive movements of the facial muscles, attacks 
 of dizziness and nausea, or even the convulsive 
 seizures of epilepsy, without the real cause being 
 suspected. Short of such tangible manifestations 
 of nerve exhaustion, there may be a steady nerve 
 waste that leads to perpetual brain fatigue with 
 attendant irritability, lack of power of concentra- 
 tion, failure of memory, and insomnia leading to 
 depression and even to mental overthrow. 
 
 Says Dr. Clark: " Insomnia is a prominent 
 symptom of eye-strain; this leads to depression 
 which in turn may lead to the alcohol or morphine 
 habit. There is no form of functional nerve dis- 
 order that may not be caused, or aggravated by 
 eye-strain. ' ' 
 
 Dr. Gould goes farther. Not limiting the view 
 to functional disorders, he names curvature of 
 the spine among common conditions due to eye- 
 strain, the bodily distortion resulting, he says, 
 ' ' from the effort to focus defective eyes on books 
 at school and the home under improper conditions 
 as to desks and light." 
 
 11 As to the millions of common school chil- 
 dren," he says, " their ocular ills, their eye-strain, 
 and its effect upon general health, their standing
 
 178 Adding Years to Your Life 
 
 in classes, the reasons for the dullards and tru- 
 ants, and even juvenile criminals of all this big 
 book of human ills and wrong, we are now at the 
 opening page." And he adds: " Not one good 
 school desk exists in the United States, and every 
 child writes with body and head and eyes in dis- 
 ease-producing postures." 
 
 " Not one good school desk in the United 
 States ! ' ' Yet fifteen or twenty million children 
 are forced to sit at school desks * ' in disease-pro- 
 ducing postures." A dreadful indictment of our 
 educational system. Possibly it overstates the 
 facts ; but it is too near the truth to make pleasant 
 reading. 
 
 The Home Influence All Important 
 
 In a word, then, it is impossible to exaggerate 
 the dangers that attend the eye-strain that may 
 be due to a very slight error of refraction. 
 
 And the danger is peculiarly subtle because the 
 child is quite unaware of the difficulty. It may 
 even happen that astigmatism due to asymmetry 
 of the cornea is corrected by such action of the 
 ciliary muscle as will change the shape of the 
 crystalline lens in a way to correct the distortion 
 of the image and thereby give perfectly good 
 vision. 
 
 But the correction is made at the expense of 
 incessant eye-strain, which cannot fail to make its 
 effects manifest sooner or later. In such a case 
 it is impossible to detect the abnormality unless 
 the ciliary muscles are paralyzed momentarily
 
 Can You See Straight? 179 
 
 by a drug like atropin. But the interests of the 
 child demand that the error should be detected 
 and corrected by the proper glasses. 
 
 In case the eye suffers from astigmatism, and 
 in those other cases in which the two eyes have 
 different errors of accommodation, it is peculiarly 
 necessary that there should be complete correc- 
 tion of the errors, and that the correcting glasses 
 should be worn at all times. It is possible thus to 
 give normal vision and to remove eye-strain, 
 obviating the danger of incurable eye maladies 
 or permanent perversions of the nervous system. 
 
 But it is best of all to train the child from 
 infancy to use the eyes in such a way as to pre- 
 serve them in a normal condition, and thus to 
 spare him the inconvenience of the lifelong wear- 
 ing of glasses. 
 
 Wise parents are now giving heed to this mat- 
 ter of eye-strain even in the nursery ; and teachers 
 in the schools are coming to understand more 
 clearly the need of proper lighting and the vital 
 importance of using only such text-books as have 
 large, clear type. The light of the schoolroom 
 should come from the side, preferably the left. 
 Desks should be so arranged that pupils can sit 
 upright at their work, and particular effort should 
 be made to see that they do not hold their books 
 too near the eyes. 
 
 Let Dr. Gould's charge about the bad desks be 
 remembered, and his warning heeded. Any child 
 that tends constantly to scrutinize its work with 
 eyes close to the page should at once have its eyes
 
 i8o Adding Years to Your Life 
 
 examined, that its incipient shortsightedness may 
 be corrected. 
 
 But for that matter every child should have its 
 eyes examined by a competent occulist from time 
 to time, just as it should have its teeth examined 
 by a dentist. Indeed, of the two preventive meas- 
 ures, the former is by far the more important. If 
 you fail to take this simple measure to safeguard 
 the eyes of your children, you are guilty of inex- 
 cusable negligence, and the child, later in life, 
 will quite properly resent your oversight.
 
 vn 
 
 Do You Choose Your Children? 
 
 TTAVE I the right to get married? If already 
 **- married, have I the right to have chil- 
 dren? If I have children, will they be healthy in 
 mind and body, or will they be feeble-minded, or 
 consumptive, or epileptic, or so sickly and defec- 
 tive that they will be a burden to themselves and 
 to their parents? 
 
 The time is coming when every intelligent man 
 and woman must ask himself or herself such 
 questions as these, direct, personal, practical 
 questions. The new knowledge of heredity makes 
 it imperative to do so. The long controversy 
 about the relative influence of heredity and en- 
 vironment has been settled for all time. We know 
 now that the possibilities of any individual are 
 predetermined before birth. When you select a 
 marriage partner, you are predetermining the 
 character of your offspring almost as clearly and 
 as definitely as an architect is predetermining the 
 character of a building when he selects steel or 
 wood or stone or brick or concrete as building 
 material. 
 
 If your child has a wrong heredity, you can no 
 more make him a normal and healthy and clear- 
 minded individual than you can make a mar- 
 
 181
 
 1 82 Adding Years to Your Life 
 
 ble palace out of bricks or a brick house out of 
 wood. 
 
 Environment and education can do something, 
 but at best they can only supply a veneer. The 
 essential constitution and mind of the individual 
 are born and not made. Such is the clear, em- 
 phatic, and thought-provocative teaching of the 
 new heredity. 
 
 You, perhaps, are inclined to doubt this. You 
 have seen bright, healthy, robust children in 
 families where the parents were sickly or unin- 
 telligent or depraved. You have also seen defec- 
 tive children whose parents were robust and 
 intelligent. Such observations seem to deny the 
 influence of heredity. But the new studies explain 
 these anomalies ; explain them not by the citation 
 of theories merely, but by the piling up of illus- 
 trative cases, by the massing of evidence that no 
 one can ignore. If you are to select a marriage 
 partner wisely, and to give your prospective chil- 
 dren half a chance in life, you must be familiar 
 with at least the essentials of this new and im- 
 portant knowledge. 
 
 At the very beginning it must be understood 
 that we do not inherit our traits exclusively from 
 our parents. We inherit them from grandparents 
 and great-grandparents as well. 
 
 Indeed, traits of a perfectly definite character 
 our stature, the color of our eyes or hair, our 
 mental abilities may come by direct inheritance 
 from even more remote ancestors after skipping 
 two or three generations. The present writer,
 
 Do You Choose Your Children? 183 
 
 for example, has an extra tooth, an extremely 
 rare phenomenon. One of my cousins also has 
 an extra tooth. No one of our parents or grand- 
 parents had teeth different from the normal ; but 
 investigation has revealed the fact that one of our 
 great-grandparents had an extra tooth. This pe- 
 culiarity, then, is a family trait which, could we 
 trace it, would doubtless be found reappearing 
 here and there throughout the whole line of 
 ancestry. 
 
 What is true of this tangible but unimportant 
 characteristic is equally true of every other 
 physical and mental trait, from the most obscure 
 and incidental to the most prominent and 
 essential. 
 
 It may fairly be assumed that no individual 
 has any trait of body or mind that was not clearly 
 and definitely present in one or another of his 
 ancestors. Your child has certain traits and 
 capacities that no ancestors of yours have had, to 
 be sure ; but you must recall that your child has 
 two parents and that both ancestral lines affect it 
 equally. Your child has twice as many ancestors 
 as you have. 
 
 In other words, your marriage partner brings an 
 endowment of characteristics, good or bad, that are 
 weighed against the characteristics of your ances- 
 try in determining the personality of your child. 
 
 And that is why the selection of a marriage 
 partner is far and away the most momentous 
 task that you can by any possibility be called 
 upon to perform.
 
 1 84 Adding Years to Your Life 
 
 The New Knowledge of Heredity 
 
 It is no new thing, of course, to say that the 
 personality of any individual represents more or 
 less clearly the sum of the personalities of all of 
 his ancestors. But the new studies of heredity 
 show that the diverse characteristics of the many 
 ancestors are not blended in the way they were 
 formerly supposed to be blended. 
 
 Each individual is now thought of not so much 
 as representing a blend of traits as a mosaic. The 
 new studies show that there are many character- 
 istics of both body and mind that do not tend to 
 become modified through blending, but which 
 may seem altogether to disappear in a given gen- 
 eration, or even for successive generations, and 
 yet reappear with full force in a remote de- 
 scendant. 
 
 This means that each individual bears within 
 his system and may transmit to his descendants a 
 multitude of characteristics that he gives no evi- 
 dence of having and of which he is quite uncon- 
 scious. Just what these latent characteristics are 
 can be known only through study of the charac- 
 teristics of our forebears. 
 
 Did you ever stop to reflect what a complex 
 structure the so-called ancestral tree really is! 
 
 A moment thought's will make it clear that 
 every individual has an ancestry that doubles 
 with each generation as we go back. Most of us 
 know the names of our grandparents; but few of 
 us can name offhand all eight of our great-grand-
 
 Do You Choose Your Children? 185 
 
 parents, to say nothing of the sixteen members of 
 the preceding generation, or their thirty-two 
 parents. The great-grandparents of your great- 
 grandparents were sixty-four in number. They 
 lived at about the beginning of the eighteenth 
 century, so that does not carry us very far back. 
 Yet I venture to say there is not a man in America 
 who can name or trace all the members of his 
 ancestry of that generation. It would be well for 
 us all, in the light of the teaching of modern 
 heredity, if we could. 
 
 Every one of us has (or would have were it not 
 for inter-breeding) 1,024 ancestors of the tenth 
 generation; and that carries us only to the time 
 of the Pilgrim fathers. Who pretends to know 
 anything whatever about one in a hundred of 
 these f 
 
 Not even the crowned heads of Europe 
 neither Kaiser Wilhelm, King George, nor Al- 
 phonso could name, with the aid of all existing 
 records, the full list of their ancestors of that 
 tenth generation only three hundred years ago. 
 
 Yet each one of the thousand had individual 
 traits that are present, patent or latent, in the 
 germ-plasm of his descendant of to-day. As a 
 single illustration, note the Hapsburg lip, which 
 Alphonso has inherited from a known ancestress 
 (Cymburga) of the fourteenth century. 
 
 In a word, then, each of us is the bearer of a 
 message from our ancestry to our posterity. 
 
 You stand at the meeting point between galaxies 
 of ancestors and other galaxies of prospective
 
 i86 Adding Years to Your Life 
 
 progeny. In your system lies the bit of germ- 
 plasm that miracle of miracles! conveys the 
 potentialities of good and evil of all the past 
 the epitome of the racial history of all your 
 myriads of ancestors. 
 
 Nothing that you can do will change the char- 
 acter of that germ-plasm. Its potentialities are 
 fixed irrevocably. In a sense it is not a part of 
 you; it is a heritage placed temporarily in your 
 stewardship. 
 
 But it is open to you to decide whether you will 
 be a true or a false steward. You may determine 
 whether the progeny flowing from that germ- 
 plasm shall be worthy of its best possibilities, or 
 whether they shall exemplify its worst possibili- 
 ties. And the whole momentous question hinges 
 on a single decision your choice of a marriage 
 partner. 
 
 All the evolution of the past has been deter- 
 mined by mating selections ; all the progress of the 
 future will be conditioned on mating selections. 
 
 Viewed in this light, it might almost be said that 
 a couple going to the altar stand before a court 
 where thousands of ancestral ghosts sit in judg- 
 ment, ready to chorus approval or to forbid the 
 unworthy banns. It would be well for the world 
 if our dull human ears could hear the verdict 
 for none but the most foolhardy would dare to 
 ignore it. 
 
 It is not necessary, however, to invoke the gal- 
 axies of past or future to show the all-importance 
 of the marriage selection. It is quite enough to
 
 Do You Choose Your Children? 187 
 
 appeal to your own personal and selfish interests. 
 However slight your interest in the welfare of re- 
 mote posterity, you at least are concerned about 
 the welfare of your children, and that is the topic 
 at present in hand. 
 
 The Conflict of Tendencies 
 
 The central fact to get clearly in mind is that 
 in your germ-plasm are mingled the relics, so to 
 speak, of very diversified ancestors. It is obvious 
 that many of these traits are antagonistic or 
 mutually exclusive. For example, you cannot be 
 both tall and short. You cannot have both dark 
 hair and light hair ; or black eyes and blue eyes. 
 You cannot be strong and weak; healthy and un- 
 healthy; sane and insane. Yet your two parents 
 may represent these and a multitude of other 
 divergent traits. 
 
 Take, for example, the simple case of two 
 parents one of whom has black eyes (of a pure 
 strain) and the other blue eyes. It is matter of 
 observation that in such a case the children all 
 have dark eyes. But it is further to be noted that 
 these dark-eyed offspring, mated with other per- 
 sons of similar heritage, have a certain proportion 
 of children with blue eyes. 
 
 Thus the tendency to blue eyes, although sub- 
 ordinated and as it were overriden in one genera- 
 tion, reappears in the succeeding generation. 
 
 A striking illustration of the same thing is 
 obtained when a black guinea-pig is mated with a
 
 1 88 Adding Years to Your Life 
 
 white guinea-pig, as in Professor William E. 
 Castle's experiments. All the offspring are black. 
 Yet these black offspring when interbred produce 
 a certain number of white guinea-pigs, one in 
 four, to be explicit. It is obvious, then, that the 
 black guinea-pigs of the second generation have 
 latent in their systems the tendency to whiteness. 
 The tendency to blackness prevailed so far as 
 the individual was concerned; but the opposing 
 tendency was only temporarily subordinated. 
 
 A multitude of observations have shown that 
 the great variety of traits that go to make up the 
 physical and mental characteristics of human be- 
 ings are weighed against each other and trans- 
 mitted as patent or as latent characteristics. 
 
 It is obviously important to ascertain, particu- 
 larly as regards diseased conditions, which traits 
 tend to be directly transmitted from parent to 
 offspring, and which ones tend to disappear in 
 a generation and reappear in a later generation. 
 Enough facts as to this all-important matter have 
 been collected in very recent years to afford a 
 basis for the scientific selection of marriage 
 partners. 
 
 We now know that in many cases seemingly 
 normal individuals could not be mated without 
 entailing the gravest danger upon their progeny. 
 
 Ancestors and Marriage Partners 
 
 Let us make the illustration concrete. You are, 
 let us say, a young man of seemingly good health,
 
 Do You Choose Your Children? 189 
 
 and entirely normal in mind and body. You have 
 fallen in love with a young woman also sound and 
 healthy. Both of you could pass the most rigid 
 life insurance examination. Seemingly you are 
 well suited for each other. 
 
 It is true that one of your great-grandparents 
 was mentally unbalanced, but there is nothing 
 very startling in that, for investigation shows that 
 there are strains of insanity in about one-third 
 of all families. Your parents and your four 
 grandparents were of normal mentality. So why 
 give the matter a thought? In point of fact, you 
 need not, were it not for the fact that one of your 
 fiancee's grandparents was subject to epileptic 
 seizures. But if you are wise that fact will make 
 you pause. Insanity and epilepsy are not the 
 same thing, to be sure ; but they are allied neuroses 
 which operate in the same way in the scheme of 
 heredity. 
 
 It is more than likely, then, that the two neurotic 
 taints if brought together will act like fire and 
 tinder; and your offspring will be neuropathic, 
 feeble-minded or epileptic or sexually perverted 
 or destined to become insane. 
 
 So your contemplated marriage involves mat- 
 ters far more profound than the mere question 
 of your individual happiness of the moment. It 
 involves the weal or woe of those years of the 
 future when your children will be to you either 
 the supreme blessing or a source of the profound- 
 est remorse and sorrow. Dare you take the 
 hazard?
 
 igo Adding Years to Your Life 
 
 Before you answer, look about you, and con- 
 sider the families of your neighbors. More than 
 likely some of them include children that are con- 
 genitally crippled or scrofulous or " backward " 
 or vicious and depraved. You have supposed that 
 this was an unavoidable misfortune; an inex- 
 plicable " interposition of Providence." You are 
 wrong. The seeming misfortune that is bringing 
 the head of your neighbor in sorrow to the grave 
 was really of his own choosing. He predeter- 
 mined that his child should be neuropathic or 
 epileptic or deformed or congenitally blind or deaf 
 or morally depraved when he selected the mother 
 of that child. He made the choice unwittingly 
 of course. But nature makes no allowance for 
 ignorance. 
 
 You will invite the same disaster if you act 
 with like lack of foresight. 
 
 There are estimated to be four million children 
 in the United States that are classified as 
 " exceptional.'* The Binet tests show that in 
 some of our schools 30 per cent of the children 
 are below the normal standards of mental develop- 
 ment. Do you wish to be responsible for children 
 that will add to this class? 
 
 There are estimated to be 200,000 individuals 
 in the United States that rank as imbeciles. And 
 with the rarest exception the cause of imbecility 
 is heredity and heredity alone. The parents of 
 an imbecile may be mentally sound and normal; 
 but they carry inherited defects in their germ-
 
 Do You Choose Your Children? 191 
 
 plasm or their child would not be congenitally 
 defective. 
 
 And this, be it understood, applies to moral 
 defects no less than to mental. Hereditary in- 
 stability of the nervous mechanism weakness of 
 brain and mind may reveal itself differently in 
 various members of the same fraternity in one 
 case as feeble-mindedness, in another case as 
 criminality, and in yet others as epilepsy or as 
 insanity or drunkenness or debauchery. 
 
 Such details of difference as these imply are 
 often determined by the environment; but the 
 deep-seated nervous defect that underlies them 
 all is a matter of inheritance. 
 
 Your Family Tree 
 
 All this, you admit, is very harrowing ; but you 
 thank your lucky stars that your family is free 
 from any such taint. 
 
 Do not be too sure of that. Do you know the 
 names, let alone the antecedents, of your eight 
 great-grandparents? Are you quite sure that no 
 one of them was consumptive, or addicted to al- 
 cohol, or the victim of venereal diseases? One- 
 tenth of all deaths are due to consumption. So it 
 is more than an even chance that your forebears 
 of the past three generations included at least 
 one victim of this disease. 
 
 If such is really the case, there is a strain of sus- 
 ceptibility to the attacks of the tubercle bacillus 
 in your system bred in the bone, as the saying
 
 i2 Adding Years to Your Life 
 
 is however free you may be from any outward 
 indication of the fact. And the one sure way to 
 bring that latent tendency to the surface, is to 
 choose a mate who carries the same latent heredi- 
 tary tendency. 
 
 Look about you and see how many of your ac- 
 quaintance, themselves healthy, have scrofulous 
 or nervous or ill-nourished, pale, sickly children. 
 Then ask yourself whether you would knowingly 
 choose such progeny for your own. 
 
 The choice lies with you. If you mate with a 
 person of a family strain not susceptible to tuber- 
 culosis, your children will in all probability be 
 normal in this regard. Even the children of a 
 consumptive who mates with a normal person 
 may be normally resistant. But to unite two 
 tainted strains, even when the individuals them- 
 selves are normal, is to challenge fate; in effect, 
 to invoke a curse on your own progeny. " It is 
 highly undesirable," says Professor C. B. Daven- 
 port, " that two persons of weak resistance (to 
 tuberculosis) should marry, lest their children all 
 carry the weakness." 
 
 If that simple rule could be known to people in 
 general, and if they could be prevailed upon to 
 act on it, how rapidly would the fight against the 
 great white plague be carried to a successful 
 issue. 
 
 Unfortunately the time has not yet come when 
 we can hope that the average young man and 
 woman will consider such teaching as this against 
 their own individual fancies of the moment. But
 
 Do You Choose Your Children? 193 
 
 you and I, being rational persons and able to 
 match future happiness against momentary pleas- 
 ure, may ponder this teaching of the new heredity 
 to our own benefit and that of our prospective 
 children. 
 
 Some Thought-Compelling Cases 
 
 And all this, be it understood, is no mere theoriz- 
 ing. It expresses probabilities based on the study 
 of actual pedigrees. Other pedigrees that have 
 been studied include a wide variety of diseased 
 conditions. 
 
 Here, for example, is a case in which a healthy, 
 normal man and woman marry, without so much 
 as giving a thought to the fact that the father 
 of each had died of heart disease. But was it an 
 accident that of the four children born to this 
 couple two had heart trouble, and one died of 
 heart disease in infancy? 
 
 " Heart disease," says Professor Davenport, 
 " is very common, but it does not fall upon indi- 
 viduals at random, but prevailingly upon strains 
 with an inherent liability or weakness.'* 
 
 The same thing is true of other anomalies of 
 the circulatory apparatus. There are, for ex- 
 ample, families of " bleeders," persons whose 
 blood does not coagulate normally, so that even 
 very slight wounds expose them to grave danger 
 from hemorrhage. This disease has the peculiar- 
 ity that it usually affects only the males of the 
 family, yet is transmitted only by the females; 
 that is to say, a man who is a bleeder will
 
 194 Adding Years to Your Life 
 
 have normal children, but his sister, although per- 
 sonally normal, will have sons that are abnormal. 
 Here is a pedigree in which, in a fraternity of five 
 members, the three men are all bleeders. The two 
 sisters are normal; yet when married to normal 
 men these women have respectively four and five 
 sons, all of whom are bleeders. 
 
 The mothers who thus transmitted a condition 
 that was latent in their own systems had normal 
 parents and grandparents ; but one of their great- 
 uncles was a bleeder, and the hereditary character 
 of the infirmity is further attested by two afflicted 
 cousins and by a total of twenty-five bleeders in 
 closely collateral lines in the course of three 
 generations. 
 
 This pedigree, and others like it, justify the 
 conclusion that whereas male bleeders may marry 
 with relative impunity, their sisters, though them- 
 selves normal, should not have children. The 
 verdict seems harsh, but it is rational. 
 
 A similar tendency to " crossed-heredity " 
 that is, transmission from mothers to sons, or 
 from fathers to daughters occurs in connection 
 with a good many abnormalities of the eye. 
 
 Thus color-blind men do not have color-blind 
 sons, and as a rule their daughters are also 
 normal. But these normal daughters, married to 
 men of normal stock, have color-blind sons. 
 
 Similar anomalies of inheritance are found in 
 cases of the much more serious eye defect called 
 coloboma, in which the iris fails to develop nor- 
 mally, and in the condition that leads to total blind-
 
 Do You Choose Your Children? 195 
 
 ness through atrophy of the optic nerve. It is 
 declared with authority that ' ' no female with the 
 coloboma defect should have children, since all 
 sons will be defective in the structure of the pupil. 
 For males with the defect the danger in marriage 
 is also great, for either all or half of the sons of 
 such a father, although married to a woman from 
 a normal strain, will be defective, but the daugh- 
 ter will not be defective in this respect unless the 
 wife belongs to a strain with this defect." 
 
 For families having the tendency to atrophy of 
 the optic nerve the rule given is this : ' l A normal 
 son of an abnormal male may marry quite outside 
 the family with impunity, but a normal daughter 
 may transmit the defect to her sons. A defective 
 male should abstain from having children, for 
 some of his sons, at least, will probably be defec- 
 tive." 
 
 Even the most heedless person can scarcely fail 
 to pay attention to such a warning as that. The 
 possibility of producing children that are blind- 
 and doing this wilfully in defiance of the teachings 
 of heredity is one that no sane person could 
 contemplate with equanimity. 
 
 The Marriage of Cousins 
 
 Consider now a pedigree that introduces an- 
 other complication. A young man falls in love 
 with his cousin. Both are normal; so are their 
 four parents ; and they ignore the fact that one of 
 their common grandparents was deaf. The two
 
 196 Adding Years to Your Life 
 
 cousins marry and have four children, of whom 
 two are born deaf. 
 
 Here the hereditary defect has skipped two 
 generations, and there is reason to suppose that 
 it would not have reappeared but for the union of 
 cousins. The justification for this belief is found 
 in the fact that deafness may be due to a good 
 many different conditions, so the marriage of un- 
 related deaf mutes results in deafness in only 
 about one-fourth of the offspring, the low per- 
 centage being due, Professor Davenport believes, 
 to the fact of one parent bringing into the com- 
 bination what the other parent lacks, thus neutral- 
 izing the defect. But when the parents are re- 
 lated belonging therefore to the same type or 
 strain of deafness the percentage of marriages 
 yielding deaf children increases in proportion to 
 the closeness of relationship of the parents. 
 
 In one case in which the marriage partners were 
 nephew and aunt, 75 per cent of the children were 
 deaf. 
 
 It must not be supposed from this, however, 
 that there is any peculiar association between 
 deaf-mutism as such and consanguineous mar- 
 riages. A great variety of defects may be brought 
 to the surface in the same way. Thus Dr. Bemiss 
 (cited by Davenport) reported 833 consanguin- 
 eous marriages having 3,942 children, of whom 
 about one-fourth died young, and of the re- 
 mainder more than 1,100 were " defectives," 
 including deaf mutes, the blind, idiots, insane, 
 epileptics, and the deformed and scrofulous.
 
 Do You Choose Your Children? 197 
 
 Dr. Howe reports seventeen consanguineous 
 marriages that produced 50 per cent of idiots. 
 
 The point is that any defects in the germ-plasm 
 tend to reveal themselves in the offspring of 
 cousin marriages. Here is a family in which there 
 is no known taint, but in which it becomes the 
 fashion for cousins to marry. In the first genera- 
 tion under observation healthy cousins marry, and 
 the second generation shows one individual in 
 three suffering from the condition of muscular 
 lack of tone and responsiveness known as 
 Thomson's disease. Three cousin marriages 
 occur in this second generation, five of the six 
 partners being normal. But in the ensuing gen- 
 eration, of eight children born to the three couples 
 four have Thomsen's disease, two have nerve and 
 lung trouble, and only one is normal. 
 
 Here the cousin matings brought out a strain 
 of abnormality that had so completely disap- 
 peared that its existence as a family trait had 
 been forgotten. 
 
 Illustrations of the evils of cousin marriages 
 may be found on a large scale in every community 
 where physical barriers to migration or social re- 
 strictions have led to much intermarrying. In 
 Martha's Vineyard close inbreeding has led to the 
 prevalence of deaf-mutism; in Point Judith to 
 idiocy and insanity; in an island off the coast of 
 Maine to " intellectual dulness "; in Block Island 
 to loss of fecundity; in some of the " Banks " off 
 the coast of North Carolina to suspiciousness and 
 mental feebleness; in a peninsula on the east
 
 198 Adding Years to Your Life 
 
 coast of the Chesapeake Bay to dwarfness; in 
 some of the Bahamas to idiocy and blindness. 
 
 " Thus," says Davenport, who reports these 
 instances, " there is no one taint that results 
 from the marriage of kin ; the result is determined 
 by the specific defect in the germ-plasm of the 
 common ancestor." 
 
 It follows that if there is no hereditary weak- 
 ness in 'your family no taint of mental or 
 physical disease you may marry your cousin 
 without jeopardizing the interests of your pros- 
 pective offspring. But if there is a heritable taint 
 and very few families are altogether free from 
 one defect or another you magnify the defect by 
 the union of two strains that carry it. A totally 
 unrelated person may have the same defect; but 
 your cousin is almost sure to have it, because you 
 inherit from the same ancestor. 
 
 So the marriage of cousins should never be con- 
 summated without very careful scrutiny of the 
 common pedigree. 
 
 The Individual and the Race 
 
 When the marriage of persons related in some 
 degree of cousinship is in question, it is well to 
 recall that the entire population of a country that 
 has been long inhabited and not much subject to 
 immigration, comes to be made up of closely inter- 
 woven elements. 
 
 To see how inevitable this is, we have only to 
 recall that the descendants of a single individual,
 
 Do You Choose Your Children? 199 
 
 were each of his progeny to have on the average 
 five children, amount to more than eight million, 
 in the tenth generation. Ten generations span 
 little more than three centuries ; so the total popu- 
 lation of America to-day might be accounted for 
 as descended from a dozen couples or so that came 
 over in the Mayflower provided there had been 
 no intermarrying. But it is equally obvious that 
 marriage partners could not have been found for 
 the successive generations without constant inter- 
 marrying. 
 
 In point of fact, all students of genealogy know 
 that where a population is established in a re- 
 stricted territory a few generations suffice to make 
 the entire community related within recognized 
 degrees of consanguinity. In such communities, 
 family traits and any heritable weaknesses be- 
 come accentuated. The " racial characteristics " 
 of New-Englanders, for example, and of Virgin- 
 ians, furnish illustrations in point. In the long 
 run the laws of heredity operate to bring to the 
 surface the undesirable latent traits, which, when 
 they become sufficiently preponderant in the com- 
 munity, tell of racial degeneration. 
 
 Nothing saves a closely inbred race that has 
 reached this stage except the infusion of good new 
 blood from outside. 
 
 But in view of this intermingling of descend- 
 ants, in virtue of which everyone in a given region 
 becomes more or less closely related to everyone 
 else, how does anyone escape being tainted with 
 a variety of heritable defects? Until very re-
 
 200 Adding Years to Your Life 
 
 cently no one could answer that question in any- 
 thing but the vaguest way, but the new studies 
 of heredity have supplied a perfectly definite 
 and precise answer, the gist of which is that the 
 same traits are not transmitted to all the offspring 
 of a given couple, and that by proper selection 
 even the worst defect may be bred out of a family. 
 
 The Same Laws for Animal and Man 
 
 To make the matter clear, we may draw an illus- 
 tration from the animal world. It is quite valid to 
 do so, because it is fully conceded that the same 
 laws of heredity apply to animals and to men. 
 Indeed, the knowledge that is now being applied 
 to human matings was first gained by experiments 
 with plants and animals. It will be recalled that 
 the new methods of treating human diseases were 
 discovered in the same way. 
 
 Let us take, then, the case of the guinea-pigs 
 already referred to. We saw that if a black and 
 white guinea-pig, both of pure strains, were 
 mated, the offspring are all black. We saw fur- 
 ther that if a pair of these offspring of the first 
 filial generation are interbred, the progeny show 
 three black individuals and one white in each 
 group of four. It remains now to follow up the 
 experiment. 
 
 It appears, then, that if the white members of 
 the fraternity are interbred, they will produce 
 only white offspring. They are to all intents and 
 purposes of a pure white breed. Notwithstand-
 
 Do You Choose Your Children? 201 
 
 ing the fact that both their parents are black, the 
 tendency to blackness has utterly disappeared 
 from their germ-plasm. 
 
 If meantime the black members of the frater- 
 nity are interbred, it will presently be revealed 
 that, whereas they all look alike, there are deep- 
 seated differences between them. Certain among 
 them, if interbred, willproduce only black off spring. 
 Kegardless of the fact that one of their grand- 
 parents was white, all tendency to whiteness has 
 disappeared from their germ-plasm. But there 
 are others among the black members of the fra- 
 ternity which, if interbred, produce both black and 
 white offspring, in the proportion of three to one. 
 Their germ-plasm, like that of their parents, con- 
 tains elements of both blackness and whiteness. 
 
 This seems remarkable enough ; and the wonder 
 grows when we learn that however often the ex- 
 periments are repeated the same results are ob- 
 tained generation after generation. Of any four 
 grandchildren (on the average) of a black and a 
 white guinea-pig, one is pure black, with no tend- 
 ency to whiteness; one is pure white, with no 
 tendency to blackness; and two are individually 
 black, but with a latent tendency to whiteness 
 that will make about one-fourth of their offspring 
 white. 
 
 Thus it appears that the offspring of the same 
 parents brothers and sisters in the same litter 
 differ radically from one another not only in their 
 personal traits, but in the latent traits carried in 
 their germ-plasm. Some are pure black, some
 
 202 Adding Years to Your Life 
 
 are pure white, and some are mixed; and the 
 same law of heredity accounts for them all. 
 
 Now for the application. It appears that most 
 of the heritable human traits we have all along 
 been considering act in inheritance precisely as 
 do the qualities of blackness and whiteness in the 
 guinea-pig. As regards a large number of condi- 
 tions, normality may be said to be matched against 
 abnormality as black is matched against white in 
 the animal. When a normal person mates with a 
 feeble-minded person, for example, the children 
 are likely to be normal, but with a latent tendency 
 of abnormality. Of the offspring of these chil- 
 dren (mated with others of similar heritage), out 
 of each group of four, one will be purely normal, 
 two will be seemingly normal but with a latent 
 tendency to transmit abnormality, and one will 
 be abnormal. 
 
 Thus it appears that three out of four of the 
 grandchildren of an imbecile, may be altogether 
 normal, and that one of the three may have not 
 even the latent tendency to the affliction of their 
 grandparent. The other two have the latent tend- 
 ency, but it need never reappear in their offspring 
 if they mate with normal persons. 
 
 And this fact is, on the whole, the most wonder- 
 ful, as it is the most beneficent, revelation of the 
 new heredity. 
 
 In effect, good health preponderates over ill 
 health in transmission ; a trait that has been bred 
 into your family through the injudicious mating 
 of an ancestor may be bred out for all time by
 
 Do You Choose Your Children? 203 
 
 judicious mating. In the course of three genera- 
 tions purely normal strains may be developed 
 from families that were permeated with abnor- 
 mality. And to accomplish this, nothing more is 
 required than the judicious selection of marriage 
 partners. 
 
 But, on the other hand, the selection of wrong 
 partners results in abnormal children with equal 
 certainty. Dr. H. H. Goddard, of the Training 
 School for Defectives at Vineland, New Jersey, 
 has gathered a mass of evidence showing that the 
 mating of two feeble-minded persons produces 
 only feeble-minded offspring. Similarly Drs. 
 Cannon and Rozanoff, of the Kings Park Hospital 
 for the Insane, find that when both parents have 
 any form of * ' functional ' ' insanity, * * all of their 
 children will * go insane.' If one parent is insane 
 and the other normal but of insane stock, half of 
 the children tend to become insane. When both 
 parents, though normal, belong to insane stock, 
 about one-fourth of the children become insane." 
 
 Thus these practical studies emphasize anew 
 the lesson that everything depends upon the 
 matings. 
 
 New Tribes of Plants and Animals 
 
 These all-important laws of heredity have been 
 understood only in very recent times. A clue to 
 their interpretation was gained through study of 
 hereditary transmission of a great variety of 
 characteristics in plants and animals. The 
 pioneer work was done by the Austro-Silesian
 
 204 Adding Years to Your Life 
 
 monk, Gregor Mendel, a full generation ago, but 
 no one paid any attention to his work until it was 
 rediscovered by the famous Professor de Vries of 
 Amsterdam. 
 
 In the meantime, Luther Burbank, at Santa 
 Rosa, California, had independently discovered 
 the principle of the segregation of characters and 
 their recombination in the second generation ; and 
 he has made this the basis of his wonderful ex- 
 periments in the development of new varieties 
 and even of new species. 
 
 Mendel's experiments were made chiefly with 
 ordinary garden peas. He found that if he inter- 
 bred a tall variety of pea with a short variety, 
 tallness prevailed in the offspring, and shortness 
 remained only as a latent tendency that could 
 reappear in a later generation. In a similar way 
 such traits as white flowers versus pink flowers; 
 green pods versus yellow pods; hairiness of leaf 
 versus smoothness of leaf; could be matched 
 against one another, and experiment would show 
 which of the mutually exclusive traits would 
 directly reappear in the third generation. 
 
 It was discovered that each particular trait 
 showed always the same hereditary capacities in 
 this regard. Tallness, for example, is always 
 " dominant "; shortness, always " recessive." 
 
 Similar tests have now been applied to a great 
 variety of antagonistic and complementary traits 
 of many species of plants and animals. Thus 
 Professor Punnett in England and Professor 
 Davenport in America have made classical experi-
 
 Louis Pasteur 
 
 Dr. Alexis Carrel 
 
 Professor Metchnikoff Professor Biffin 
 
 Four of the best known scientists
 
 Do You Choose Your Children? 205 
 
 merits with fowls; and Professor Castle at Har- 
 vard, has elaborately tested the hereditary 
 characteristics of mice, guinea-pigs, and rabbits. 
 
 By utilizing the knowledge thus gained, it is 
 possible to produce new breeds of plants or ani- 
 mals in the course of three generations. Thus Mr. 
 Woods, of Cambridge, England, by crossing a 
 white-faced race of horned sheep with a black- 
 faced hornless race has been able to produce a 
 white-faced race without horns. 
 
 Professor Biffin, also of Cambridge, has crossed 
 two strains of wheat, one of which produced large 
 kernels but was susceptible to the plant disease 
 called rust, whereas the other produced small 
 kernels but was insusceptible to this disease ; and 
 in the third generation has produced a new breed 
 combining large kernels and resistance to disease. 
 It is estimated that the production of this new 
 breed of wheat will save the British farmer many 
 million of dollars annually. 
 
 But all such experiments are of course of in- 
 significant value compared with the direct study 
 of the heredity of human characteristics. 
 
 To secure data as to these, the Department of 
 Experimental Evolution of the Carnegie Institu- 
 tion, with Professor C. B. Davenport at its head, 
 has for some years been collecting human pedi- 
 grees. These records are the chief source of what 
 is now known about the heredity of diseased con- 
 ditions ; and already they are sufficiently collated 
 to afford an invaluable guide in the practical mat- 
 ter of the selection of marriage partners.
 
 206 Adding Years to Your Life 
 
 Salvation Through Wise Selection 
 
 In the light of the new knowledge, the message 
 of heredity is not fatalistic. 
 
 It is true that your tendencies and mine were 
 fixed irrevocably before birth. From that con- 
 clusion there is no escape. You may have in- 
 herited a family taint that your brothers and 
 sisters have escaped. But it does not follow that 
 you must pass that taint on to your children. On 
 the contrary, as we have seen, the traits of your 
 prospective offspring are to be determined very 
 largely by your own choice. 
 
 I If you wish to have strong, healthy, sane chil- 
 dren, it is (barring a few exceptional cases) open 
 to you to have such children. You make the choice 
 when you select a marriage partner. 
 
 That is the inspiring, the wonderful message of 
 the new heredity. It shows that it is largely open 
 to your choice whether the good traits or the bad 
 traits that are latent in your germ-plasm shall 
 become operative in the personalities of your chil- 
 dren. You may accentuate strains of abnormality 
 or disease that existed in some of your ancestors, 
 or you may eliminate such strains, accordingly as 
 you choose ill or well. There is no sorrow like 
 that of having offspring that are diseased or 
 crippled or depraved. So you are juggling with 
 your own happiness when you 'make selection of 
 a marriage partner without considering the com- 
 ing generation. 
 
 The new heredity does not tell you whom to
 
 Do You Choose Your Children? 207 
 
 select as a parent for your children; but it can 
 tell you whom not to select. 
 
 The one simple, all-encompassing rule is this: 
 do not marry into a family that carries a defect 
 of a kind that is carried also in your own family 
 strain. If, for example, one of your parents died 
 of consumption, you know that susceptibility to 
 the tubercle bacillus is latent in your germ-plasm, 
 even though you personally are thoroughly resist- 
 ant. It would be the height of folly for you to 
 marry an individual whose germ-plasm carries a 
 similar taint of susceptibility, even though this 
 individual were also personally normal. 
 
 Yet the rule may be modified to this extent in 
 accordance with the teaching of the new heredity: 
 if the consumptive member of your direct an- 
 cestral line was as far removed as a great-grand- 
 parent ; and if you have at least three brothers or 
 sisters, all of whom are normally resistant, you 
 are justified in assuming that (through wise se- 
 lection) the taint has been bred out of the 
 particular strain to which you belong; and this 
 despite the possibility that you have uncles and 
 aunts and cousins that are consumptive. 
 
 All this refers, it will be understood, to the va- 
 rious abnormal conditions that tend to remain 
 latent in a generation and to reappear under un- 
 favorable conditions in later generations. It must 
 not be overlooked that there are certain diseased 
 conditions that are directly transmissible from 
 parent to child and which, therefore, do not come 
 within the scope of the formula just given.
 
 ao8 Adding Years to Your Life 
 
 For example, there is that protean malady 
 syphilis; there is the painful eye disease called 
 glaucoma; and the systemic condition producing 
 diabetes. Doubtless these directly transmissible 
 conditions (in particular venereal diseases) were 
 chiefly in the minds of the Chicago clergymen who 
 recently declared that in future they would refuse 
 to perform the marriage ceremony unless medical 
 certificates were presented along with marriage 
 licenses. 
 
 Of similar import is the proposed New York 
 marriage law requiring a certificate showing free- 
 dom from disease " due to immorality." 
 
 In the light of all the evidence we have just ex- 
 amined, it is obvious that a mere personal bill of 
 health carries us only a small way toward the 
 goal of safety. Still it is a beginning, and as such 
 it marks notable progress. Ten years ago such 
 a suggestion could hardly have been tolerated. 
 Now there is every prospect that we shall soon be 
 prepared to go much farther, challenging not 
 merely the personal health and normality of the 
 marriage applicant, but to what is sometimes 
 even more important his family history as well. 
 
 What might be called the negative side of the 
 problem has already received attention in the 
 laws permitting the sterilization of criminals, 
 which are in vogue in several States. Questions 
 of heredity in relation to the hordes of immigrants 
 from the lower order of population of Europe 
 are also receiving recognition. The fact that 5,000 
 aliens are public charges in the hospitals for the
 
 Do You Choose Your Children? 209 
 
 insane of New York State alone challenges public 
 attention. 
 
 It is not pleasant to think that our children must 
 interbreed with the children of atavistic strains of 
 the race. 
 
 Moreover there are students of heredity who 
 call attention to the menace of a negro population 
 which has doubled with each generation till the 
 700,000 individuals of Colonial times have become 
 10,000,000. The very thought of miscegenation is 
 repulsive, yet statistics show us that in some 
 States more .than 50 per cent of the colored popu- 
 lation carries a recognized strain of white blood. 
 Here and there the question is raised as to 
 whether it may not become necessary to restrict 
 the fecundity of the negro population that the 
 intellectual status of the American race be not 
 hampered by too large an incubus. 
 
 Your Children 
 
 All these larger racial questions have a personal 
 bearing for each of us if rightly considered; but 
 our present purpose concerns largely the question 
 of the application of the new laws of heredity to 
 the average normal individual. 
 
 It is obvious that you cannot avail yourself of 
 the knowledge supplied by the new studies of 
 heredity, in its practical application to your own 
 case, unless you can gain detailed information as 
 to the traits and characteristics, normal and ab-
 
 2io Adding Years to Your Life 
 
 normal, of your own ancestors for at least two or 
 three generations. 
 
 In this view the study of family trees takes on 
 new meaning. Once genealogy was a theme for 
 the dilettante. It now becomes a study of the ut- 
 most practicality for every one of us, in our own 
 interests and the interests of our children. 
 
 The really important question for each individ- 
 ual is this : How shall I set about to investigate 
 my own pedigree ? 
 
 It is obvious that ordinary genealogical tables 
 are of little value ; they fail to give precisely the 
 information about health and disease that is most 
 to be desired. Probably your best resource will 
 be found in your family physician. In particular 
 if there is in your community a physician of the 
 elder generation, who knew your grandparents 
 and perhaps their grandparents, his recollections 
 and in particular his case-book records may prove 
 invaluable. Other clues may be gained by con- 
 sulting aunts and uncles or other relatives, some 
 of whom are pretty sure to have an interest in the 
 family history and to recall facts about the health 
 of your various ancestors, the causes of death, 
 and the like, that will be of value in piecing out 
 your chart of heredity. 
 
 It is clear that such investigation of family 
 traits as is here suggested which becomes doubly 
 arduous when we reflect that it must be applied 
 also to the family of your proposed marriage 
 partner involves search that will often prove dif- 
 ficult. But when we reflect on the care with which
 
 Do You Choose Your Children? 211 
 
 breeders of animals trace and guard the pedigrees 
 of their select stocks of dogs and cattle and horses, 
 it would seem as if intelligent human beings might 
 be willing to safeguard the interests of their 
 progeny with at least as much assiduity. 
 
 If you say that this seems to rob marriage of 
 all romance, I content myself with suggesting that 
 there is nothing appealingly romantic about a 
 brood of feeble-minded or tubercular or epileptic 
 children. 
 
 I would suggest, then, that every reader of these 
 lines should undertake a personal investigation 
 as to his own ancestry, with reference to heritable 
 abnormalities of mind and body. 
 
 If you are in doubt as to the best method of 
 procedure, you can secure practical information 
 by addressing the Eugenics Record Office at Cold 
 Spring Harbor, Long Island, N. Y. Not only will 
 the investigators there be glad of your co-opera- 
 tion in securing genealogical records, but the 
 bureau proffers its services free of charge to per- 
 sons seeking advice as to the consequences of 
 proposed marriage matings. Thus you may have 
 the advantage of expert advice based upon the 
 fullest collection of records of human matings 
 and their results that is anywhere in existence; 
 indeed, the only comprehensive set of records of 
 the kind that has been made for its purely scien- 
 tific value. 
 
 What the scrutiny of your own pedigree teaches 
 you regarding your own germ-plasm will be use- 
 ful precisely in proportion as you apply the
 
 2ia Adding Years to Your Life 
 
 knowledge in the interests of your progeny. By 
 letting your passion of the moment overmaster 
 your judgment, you may be responsible for off- 
 spring that will rebuke you every hour of your 
 life. By making practical application o/ your 
 knowledge, you may avail yourself of the hopeful 
 message of heredity and may give yourself rea- 
 sonable assurance of such a coterie of children and 
 grandchildren as may justly fulfil the Scriptural 
 injunction to rise up and call you blessed.
 
 vm 
 
 Give Your Children a Chance 
 
 ARE you doing the right thing by your chil- 
 *" dren? The question may sound almost in- 
 sulting. It is not so intended. You mean to do 
 the right thing of course. Your life is wrapped 
 up in that of your offspring. But is your attitude 
 toward them determined by wisdom as well as by 
 right motives? 
 
 Are you aware that the entire future of your 
 child may be vitiated by some ill-advised discipli- 
 nary act of yours? 
 
 Do you know that the physical stature of your 
 child may be stunted by the ill-selected food you 
 give it, and that its mental state and moral nature 
 may be even more hopelessly dwarfed and per- 
 verted by the wrong influences to which you quite 
 unwittingly subject it during the first .three or 
 four years of its life! 
 
 Do you realize that your failure to give ade- 
 quate sex-instruction to your child in its earliest 
 years, or your carelessness in the selection of a 
 nurse or of child companions, may make a per- 
 verted being out of one who otherwise might 
 have lived a useful and happy life ? 
 
 These are matters that challenge your atten- 
 
 213
 
 214 Adding Years to Your Life 
 
 tion and lie closer than almost any others to your 
 interests. 
 
 Unless your co-operation can be secured, all the 
 efforts of the professional educators will be un- 
 availing. Indeed, to a large extent the task of 
 the educators is to undo what has been unwittingly 
 done in the way of warping the mind of the 
 child. The education of the school should supple- 
 ment the education of the home ; but under exist- 
 ing conditions the task of the school teacher is 
 too often not to supplement but to correct. 
 
 Is your child among those who are subject to 
 such bad influences at home that the task of 
 rightly educating it in the school is made doubly 
 difficult, not to say impossible! 
 
 Such are the thoughts with which you should 
 contemplate the reports of the remarkable gather- 
 ing of educators from all over the world that was 
 in session (in the summer of 1913) at Buffalo, 
 New York, a gathering held under the patronage 
 of the President of the United States, presided 
 over by President Emeritus Eliot, of Harvard, 
 and officially known as the Fourth International 
 Congress of School Hygiene. The proceedings 
 of that congress have far more vital and poignant 
 interest for every parent than can possibly attach 
 to the proceedings of any political body or other 
 association concerned with the affairs of adults. 
 For it dealt with the interests of the coming gen- 
 eration, that section of the population which is 
 always in the majority and which will control all 
 the possibilities of the future.
 
 Give Your Children a Chance 215 
 
 Scope of the School Congress 
 
 The subjects under discussion at the Congress 
 of School Hygiene were such matters as these: 
 The hygiene of school building, grounds, material, 
 equipment, and upkeep ; the hygiene of school ad- 
 ministration, curriculum, and schedule; medical, 
 hygienic, and sanitary supervision in the class. 
 There were symposiums organized by various na- 
 tional societies, dealing with such subjects as 
 moral hygiene, school feeding, sex hygiene, tuber- 
 culosis among school children, child labor, and 
 physical education. Among the subjects to which 
 special sessions were devoted were fatigue and 
 nervousness among school children, mental hy- 
 giene, play and athletics, the Binet-Simon scale, 
 and the conservation of vision. 
 
 The spirt of the congress was well presented in 
 a preliminary announcement by the program com- 
 mittee, which expressed a desire that the papers 
 presented should deal largely with the results 
 secured through the practical application of 
 scientific facts and procedures of school hygiene, 
 and with the results of scientific investigation and 
 laboratory research. 
 
 Especial stress was laid on the desire to secure 
 papers relating to rural hygiene, and village 
 school hygiene, subjects that hitherto had been 
 sadly neglected. 
 
 The development of an international organiza- 
 tion having such sponsors and devoted to the 
 health of the school child is a notable sign of the
 
 2i6 Adding Years to Your Life 
 
 times. The great strides of preventive medicine 
 in recent decades have led to the preservation of 
 a vast number of infant lives that formerly would 
 have been sacrificed, and as a natural sequel the 
 school population has been tremendously aug- 
 mented. It has been exceedingly difficult in many 
 quarters to provide proper school-room accom- 
 modations. Undue crowding in rooms not prop- 
 erly ventilated or lighted has had its inevitable 
 effects in vitiating the health of large numbers of 
 future citizens. 
 
 But educators are now alive to the evils of the 
 situation, and the International Congress of 
 Hygiene will prove without doubt a reformative 
 influence of tremendous importance. 
 
 Teachers from all over the country who at- 
 tended the conferences will return to their local 
 schools with a fund of information that will be 
 invaluable. The results will before long be meas- 
 urable in the improved health of tens of thousands 
 of children. 
 
 Home Training 
 
 But while this movement for the betterment of 
 hygienic conditions in the schools must be admit- 
 ted on all hands to be of vast importance, the ac- 
 tivities of the educators must be supplemented by 
 intelligent home supervision, or their best efforts 
 will be largely neutralized. The most perfect 
 system of school hygiene brings its direct influ- 
 ence to bear on the child for only a few hours 
 each day, whereas the home influence is perennial.
 
 Give Your Children a Chance 217 
 
 Moreover, the school influence does not begin 
 until the most important period for the building 
 of the individual constitution and character has 
 passed. 
 
 Few parents realize the extent to which the 
 physical and mental life of the adult is predeter- 
 mined by the conditions of infancy and earliest 
 childhood. It is essential that you should clearly 
 understand that the future of your child will 
 largely be determined for good or ill, by the treat- 
 ment to which it is subjected during the first three 
 or four years of its life. Eight treatment during 
 this period may give it a start that can with diffi- 
 culty be checked even by adverse conditions after- 
 ward; wrong treatment gives it a handicap that 
 can never be altogether overcome even under the 
 most favorable influences of later life. The old 
 familiar saw about the bent twig epitomizes a 
 fundamental truth. 
 
 The Value of Mother's Milk 
 
 At the very threshold of life, a large proportion 
 of infants are handicapped by improper feeding: 
 Specialists are agreed that there is only one really 
 correct diet for the infant and that is mother's 
 milk. 
 
 In a recent address given under the auspices 
 of the Council of Health and Public Instruction of 
 the American Medical Association of the Women's 
 Municipal League of Boston, Dr. Thomas F. Har- 
 rington emphasized the fact that the subject of
 
 2i8 Adding Years to Your Life 
 
 infant feeding must be treated not as an ethical 
 question alone but as an important problem of 
 preventive medicine. 
 
 1 ' It is an undisputed fact," said Dr. Harring- 
 ton, " that certain vital tendencies which make 
 for the welfare of the infant, such as immunity 
 against certain infectious diseases are transmit- 
 ted through the mother's milk to her child. 
 Neither a wet-nurse's breast-milk nor a cow's milk 
 can do this for the child." 
 
 " From 80 to 90 per cent of all deaths from 
 gastro-intestinal disease among infants takes 
 place in the artifically fed ; or ten bottle-fed babies 
 die to one which is breast-fed. In institutions it 
 has been found that the death-rate is frequently 
 from 90 to 100 per cent when babies are separated 
 from their mothers. During the siege of Paris 
 (1870-71) the women were compelled to nurse 
 their own babies on account of the absence of 
 cow's milk. Infant mortality under one year fell 
 from 33 to 7 per cent. During the cotton famine 
 of 1860 women were not at work in the mills. 
 They nursed their babies and one-half of the in- 
 fant mortality disappeared." 
 
 These are facts that every mother should take 
 to heart. It seems impossible to escape the con- 
 clusion that the healthy mother who wilfully re- 
 fuses to nurse her child directly threatens not 
 merely the health but the life of her offspring. 
 
 After the child has passed the gauntlet of in- 
 fancy, the question of its proper feeding remains 
 a highly important one. Dr. Lewellys F. Barker,
 
 Give Your Children a Chance 219 
 
 of Johns Hopkins University, says that " faulty 
 feeding in infancy and early childhood may lead 
 to such impoverishment of the tissues and such a 
 stunting of growth that the ill effects can never 
 be recovered from in later life. A considerable 
 proportion of the intellectual and moral inferiori- 
 ties among our people is fairly attributable to im- 
 perfect nutrition at this early age." 
 
 Dr. Barker declares that many parents make a 
 very vital mistake in allowing the caprice of the 
 child to influence its diet. " We know the foods 
 that are suitable for children," he says, " and, 
 knowing these, the children should be provided 
 with them in suitable amounts and should be re- 
 quired to eat them, largely independent of choice. 
 The child that learns to eat and digest all whole- 
 some foods and who is not permitted to cultivate 
 little food antipathies makes a good start and 
 avoids one of the worst pitfalls of life with which 
 medical men are very familiar, namely, a finical 
 anxiety concerning the effects of various foods, all 
 too likely to develop into a hypochondriacal 
 state." 
 
 While thus arguing the value of a varied dietary 
 of wholesome foods, it is well also to emphasize 
 certain restrictions. In particular it should be 
 known to every parent that tea, coffee, and alcohol 
 in any form are deleterious to the growing child 
 and should be absolutely interdicted. This may 
 be stated without reserve. It is a point regarding 
 which all competent authorities are in perfect 
 agreement.
 
 220 Adding Years to Your Life 
 
 If you allow your child to develop a taste for 
 any of these beverages, you do it a positive injury. 
 
 New Interest in Children 
 
 Only in the most recent times has anything like 
 a clear and full comprehension been attained, by 
 educators in general, as to the share which home 
 influence and education outside the schoolroom 
 must always play in the development of mind and 
 character, and as to the paramount importance of 
 the child in determining the future welfare of the 
 state. 
 
 President G. Stanley Hall, of Clark University, 
 emphasizes this in a recent address before the 
 American Sociological Society, in which he refers 
 to " the remarkable new interest in childhood, 
 which in many respects in this country had grown 
 colder, more formal and oblivious than in any 
 land or period in the world, but which has lately 
 resulted in the formation of some hundred and 
 eleven (as we classify them) organizations for 
 child welfare and benefit, and in a renaissance of 
 interest in work for children so great that some 
 enthusiasts have even wanted to call this the cen- 
 tury of the child. 
 
 " What does this recent awakening to the na- 
 ture and needs of children, that is now pervading 
 all civilized countries and has resulted in the 
 institution of many academic chairs, laboratories, 
 clinics, journals, and a vast and rapidly growing 
 body of literature, really mean? It certainly
 
 Give Your Children a Chance 221 
 
 marks an extension of our social consciousness, 
 an enlargement of our interests, and a new awak- 
 ening of our duties to the young." 
 
 It goes without saying that a few leaders of 
 thought prominent among them President Hall 
 himself have long recognized the importance of 
 the subject which is now being brought to the at- 
 tention of the general public. Every experienced 
 alienist has seen cases of profound perversion of 
 mind, which could be traced directly to incidents 
 of childhood. 
 
 And no wise student of the subject has doubted 
 that every experience of childhood puts its mark 
 indelibly upon the brain and mind of the indi- 
 vidual. 
 
 Perhaps it seems incomprehensible to you that 
 a fright experienced by your child at the age of 
 two or three years can be instrumental in deter- 
 mining the complexion of mind of that child after 
 it has come to adult age, can, for example, give 
 it a life-long inherent timidity that will dominate 
 it under given conditions. Such, however, is the 
 fact; and a clear recognition by every parent of 
 this elementary truth would mark a new era in 
 the treatment of the child, and in the social prog- 
 ress of humanity in general. 
 
 Says the Italian physiologist Mosso: " Every 
 ugly thing told to the child, every shock, every 
 fright given him, will remain like a minute 
 splinter in the flesh, to torture him all his life 
 long." Dr. Barker, in quoting this statement with 
 approval, points out that " in Greece and Home
 
 222 Adding Years to Your Life 
 
 the children were frightened with the lamias or 
 female demons who would charm them and suck 
 their blood, with the one-eyed Cyclops or with a 
 block god, Mercury, who would come to carry 
 them away. ' ' And he adds : * * This very perni- 
 cious error in education still prevails. The 
 mother, the nurse, the maid, and the servants still 
 frighten the child with tales of the bogeyman, of 
 goblins, or ogres, of wizards, and of witches." 
 
 Such treatment not only makes life a burden 
 to the child, but * ' sometimes fears are thus started 
 which last through life." 
 
 Dr. Barker urges that instead of thus stimulat- 
 ing fears, the wise parent will endeavor to teach 
 the child to be courageous and not to have fear 
 of being alone, or of the dark, or of thunder and 
 lightning. Certain fears, common to childhood, 
 he says, are easily overcome, especially through 
 the example of courage set by parent, nurse, or 
 teacher. There are cases, however, in which the 
 fears are a symptom of disease. 
 
 Thus a young girl brought to Dr. Barker be- 
 cause of an unaccountable, persistent, and dis- 
 tressing fear of " burglars in the house," was 
 found to be suffering from exophthalmic goitre. 
 " On removal of a portion of the thyroid gland 
 by Dr. Halsted the child rapidly improved and on 
 last report was only occasionally troubled by the 
 fear; it seems probable that she will soon be en- 
 tirely free from it. Children who suffer from 
 * night terrors ' often have adenoid growths in 
 the nasopharynx ; on removal of the growth by a
 
 Give Your Children a Chance 223 
 
 slight operation the * night terrors ' disappear.'* 
 Bear these cases in mind, if your child is unduly 
 timid. Do what you can to allay its fears by pre- 
 cept and example. And if the fears persist, con- 
 sult a physician. 
 
 Actual Age and Mental Age 
 
 It has been said pertinently by a German nerve 
 specialist, Dr. H. M. Oppenheim, that a child's 
 childishness is its greatest asset. It is always a 
 misfortune for children to be unduly associated 
 with other children much older than themselves 
 or with adults. Children who are made to visit 
 museums, picture galleries, and the like, or listen 
 to conversation or lectures unsuited to their years, 
 not only do not benefit thereby, but suffer positive 
 injury. 
 
 These things should come in their time and 
 place and cannot advantageously be forced on the 
 attention of the undeveloped mind. 
 
 You should never forget that the interests of 
 your child are naturally and properly different 
 from your interests. It is in the main normal that 
 your children should enjoy the childish sports 
 and diversions which you once enjoyed. So do 
 not attempt to direct the activities of the child 
 into channels that would be normal only at a later 
 period of mental development. The best safe- 
 guard against this mistake is to see that the child 
 associates largely with other children of its own 
 age. To this end and for many reasons it is de-
 
 224 Adding Years to Your Life 
 
 sirable that the child should attend the public 
 schools, being there brought into contact with 
 varied personalities, and subject to the influences 
 that will most advantageously shape its own char- 
 acter. 
 
 But in attempting to follow out this idea, edu- 
 cators have in recent years come to understand 
 more and more clearly that there is danger of lay- 
 ing too much stress on the age of the child as 
 determined by count of birthdays. 
 
 Even among perfectly normal children, some in- 
 dividuals develop much more rapidly than others. 
 There is no close relation between precocity and 
 final development of mind and body. But a fail- 
 ure to recognize these facts may lead to the plac- 
 ing in the same grade of children who are really 
 at quite different stages of mental development, 
 and to the imposing of tasks that for part of the 
 pupils in the grade are very easy, while for others 
 they are unwarrantably difficult. 
 
 In recent years it has been possible to determine 
 the mental age of any given child quickly and with 
 a good degree of accuracy by application of what 
 are called the Binet-Simon tests. To supply a 
 foundation for such a determination, the French 
 psychologists Binet and Simon made elaborate 
 analyses of the mentality of large numbers of 
 children. 
 
 These experiments have furnished a basis for 
 comparison which is accepted as having a wide 
 range of applicability. 
 
 According to the scale, it is determined that the
 
 Determining the mental age of a child by the application of the 
 Binet-Simon and Sequin tests
 
 Give Your Children a Chance 225 
 
 average or normal mind at a given age can make 
 certain observations and deduce certain conclu- 
 sions which may be regarded as typical of a par- 
 ticular period of life. 
 
 Thus at a certain age a child becomes for the 
 first time able to trace the outline of a simple fig- 
 ure with a pencil; at a certain age it has learned 
 to recognize the primary colors by name ; at a cer- 
 tain age it can repeat a given number of words 
 or figures consecutively on hearing them once, and 
 so on. 
 
 By a series of such practical tests, becoming 
 more elaborate of course with the advancing age 
 of the child, a system is provided through which 
 it becomes possible to gauge the mental age of any 
 individual child irrespective of the child's actual 
 age hi years. And when such tests are applied, 
 it soon becomes evident that the school classes, as 
 ordinarily graded, contain a great many very 
 serious misfits. 
 
 There are physically well-developed boys and 
 girls of sixteen whose mental age is only ten or 
 eleven ; just as, contrariwise, there are children of 
 ten or eleven whose minds have advanced to the 
 sixteen-year-grade of perceiving and thinking ca- 
 pacity. Of course, every teacher has been vaguely 
 aware of such discrepancies, but hitherto there 
 has been no definite way of testing them with ac- 
 curacy; inasmuch as a misfit pupil might by ex- 
 cessive diligence keep his grade and struggle 
 through his examinations without realization on 
 the part of the pupil himself or of teacher or par-
 
 226 Adding Years to Your Life 
 
 ents that the effort required to produce this result 
 was an abnormal one. 
 
 The advantages both for the normal and ab- 
 normal child, in having tests applied that would 
 produce a more scientific grading are patent to 
 every educator. Hence the eagerness with which 
 the new tests have been taken up. As usual in 
 such cases enthusiasm has sometimes outrun strict 
 knowledge, and the specialists are now coming to 
 point out certain limitations of the Binet-Simon 
 tests, and in particular to urge that these tests 
 cannot advantageously be applied by amateur psy- 
 chologists; but the value of the tests as properly 
 applied by skilled investigators is freely and 
 generally admitted. 
 
 At the Buffalo Congress on School Hygiene, an 
 elaborate conference was devoted to this aspect 
 of education. 
 
 Dr. H. H. Goddard has made elaborate applica- 
 tion of the Binet-Simon tests to the children under 
 his care at the Vineland Training School for De- 
 fectives. He also tested recently a large number 
 of the school children of New York City, and his 
 studies here revealed an astonishing number of 
 defectives whose inherent mental disabilities had 
 not previously been fully recognized. 
 
 Dr. Goddard thinks that the Binet-Simon tests 
 deserve a place beside Darwin's exposition of evo- 
 lution and Mendel's laws of heredity. 
 
 The time is probably not distant when every 
 wise parent will apply similar tests to his own 
 children, and will be governed in considerable
 
 Give Your Children a Chance 227 
 
 measure in directing the education and in the 
 selection of vocations for his offspring by what 
 the tests reveal. If your child fails to get on well 
 at school, or manifests any peculiar traits that 
 cause you solicitude, it will be well for you to have 
 the Binet-Simon tests applied by a competent 
 examiner. 
 
 Nature Versus Nurture 
 
 It is eminently desirable that you should study 
 the hereditary tendencies of your children, and 
 note at the earliest possible moment what particu- 
 lar strains of ancestral traits seem to be dominant 
 in each one, for, according to the newest teachings 
 of heredity, members of the same fraternity may 
 differ very radically in this regard. 
 
 It will be obvious that children inheriting dif- 
 ferent physical and mental traits may require 
 quite different treatment. 
 
 In particular, if the study of your family history 
 shows the tendency to any given disease, say 
 tuberculosis, it will be the part of elemental wis- 
 dom to bear this fact in mind in caring for your 
 children. But after full allowance has been made 
 for all hereditary tendencies, it remains true that 
 a tremendous, and in many cases even a dominat- 
 ing, influence may be exerted by environment. 
 Take, as an extreme illustration, the case of a 
 child who is born with the utmost degree of sus- 
 ceptibility to tuberculosis. It is a truism to say 
 that notwithstanding such susceptibility the child 
 would never become tubercular were it possible to
 
 228 Adding Years to Your Life 
 
 shut it away absolutely from the invasion of the 
 tubercle bacillus. 
 
 And the same thing holds true, with equal obvi- 
 ousness, regarding each and every germ disease ; 
 that is to say, regarding practically all the mala- 
 dies that chiefly menace the health and life of the 
 infant and growing child. 
 
 Such an illustration vividly presents the case of 
 environment as against heredity. 
 
 A similar application might be made, although 
 it could not be so tangibly illustrated, with regard 
 to the mental and moral traits of the child. Here 
 also the influence of the surroundings may be 
 sufficient to determine in very large measure, 
 whether a given child shall grow up a normal 
 member of society or whether it shall become a 
 perverted criminal or an insane dependent. 
 
 But in practical life it is not possible to shelter 
 the susceptible child absolutely from the menace 
 of unwholesome surroundings. So it is necessary 
 to fortify the individual constitution by harden- 
 ing it and rendering it more or less immune to 
 the effects of adverse conditions. We are learn- 
 ing more and more as the study of germ disease 
 becomes more profound, that safety against these 
 diseases depends very largely upon the develop- 
 ment in the organism of antidotes to the bacterial 
 poisons. In specific cases, such as smallpox and 
 typhoid fever, we may aid nature by using pre- 
 ventive vaccines. But there are numerous bac- 
 terial diseases against which as yet no system of 
 preventive innoculation has been devised.
 
 Give Your Children a Chance 229 
 
 The way to fight these diseases is to bring the 
 body to the highest possible plane of general 
 health. 
 
 It is noted in every epidemic of a virulent dis- 
 ease that there are individuals who are not sus- 
 ceptible. Generally speaking, these are the 
 persons who have the largest measure of what, 
 for want of a more precise term, is commonly 
 spoken of as vitality. As a general observation, 
 the weakly and ill-nourished children in the com- 
 .munity succumb to contagious diseases where the 
 strong, well-nourished escape. 
 
 It is the part of elemental wisdom, then, to study 
 the physical traits of your children and to adopt, 
 under medical supervision, such a regimen of diet 
 and general hygiene as will give each child the 
 fullest measure of robustness of constitution that 
 its hereditary limitations permit. 
 
 It is in following out this idea on a large scale 
 that the modern hygienist advocates life in the 
 open air for children in general, and in particular 
 for those who lack inherited robustness of consti- 
 tution. 
 
 Playground Versus Schoolroom 
 
 We now know that the weakly child should be 
 kept on the playground rather than in the school- 
 room, even at the expense of retardation of its 
 book education. 
 
 A sickly child that has been kept out of school 
 altogether up to the age of seven or eight will 
 generally be farther advanced in its studies at the
 
 230 Adding Years to Your Life 
 
 age of twelve than it could possibly have been 
 had its physical health in earlier childhood been 
 sacrificed to the parental solicitude for its book 
 training. For the child with susceptible lungs 
 and, indeed, for children in general that wonder- 
 ful modern invention, the open air school, is a 
 positive boon. 
 
 As supplementing the out-of-door life for the 
 weakly child it is desirable to practise a syste- 
 matic hardening of the constitution with the aid 
 of cool baths. These should be used with judg- 
 ment, of course. To subject the child to a cool 
 bath from which it does not react healthfully would 
 be detrimental. But by beginning early and tem- 
 pering the bath to the needs of the individual, 
 gradually using cooler water as the child becomes 
 accustomed to it, it is possible to develop a hardi- 
 ness of constitution, and powers of resistance to 
 changes of temperature, which will stand the indi- 
 vidual in good stead. 
 
 To be susceptible to all changes of temperature, 
 and thus rendered perennially unhappy about the 
 weather over which we have no control, is to carry a 
 tangible handicap in the business of everyday life. 
 
 The judicious prescription of open air life and 
 cool baths for the growing child may very largely 
 give it immunity against this influence. 
 
 A child thus hardened will be but little suscep- 
 tible to ' ' taking cold ' ' ; and it will have 
 corresponding power of resistance against the 
 germs of the more virulent maladies. 
 
 The daily experience of the child that mingles
 
 Give Your Children a Chance 231 
 
 much with other children and participates in the 
 rough-and-ready games of childhood, will result 
 not only in the development of physical robust- 
 ness, but also in a considerable measure of what 
 Dr. Barker very aptly describes as psychic harden- 
 ing. Dr. Barker suggests that one reason why 
 women are more prone in later life to nervous- 
 ness than men may lie in the lesser opportunity 
 that girls have for bodily and psychic hardening 
 in the games which they play and the life which 
 they lead as children. 
 
 He particularly cautions that care should be 
 taken with young girls who show any tendency 
 to nervousness to see that not too much concession 
 is made to their likes and dislikes, since for such 
 children nothing could be more harmful than the 
 gratification of caprice. 
 
 " Especially when a child shows a tendency to 
 be nauseated by certain smells and tastes and 
 to complain of noises and a sensitiveness to bright 
 light," he urges, " the family physician should 
 be consulted, and, provided no actual disease of 
 the sense organs or brain is responsible, the proc- 
 esses of psychic hardening should at once be 
 begun." This process includes keeping the infant 
 in a normal routine despite any emotional out- 
 breaks ; in repression of outbursts of temper ; and 
 in convincing the child that it can get things by 
 controlling itself rather than by emotional ex- 
 plosions. 
 
 And as to all this, the home training may best 
 be supplemented by the wholesome influence of
 
 232 Adding Years to Your Life 
 
 association with other children. In the wonder- 
 ful commonwealth of the playground, the 
 emotional outbursts of the individual are made 
 to seem ridiculous, egoistic desires are subordi- 
 nated to the wishes of the many, and lessons in 
 self-control are inculcated that will be of utmost 
 importance in after life. 
 
 The parent who adopts the coddling process of 
 keeping his child away from the " rough " asso- 
 ciations of the playground does that child an 
 irretrievable injury. 
 
 Moral Training 
 
 As further stabilizing the developing mind and 
 giving it a just estimate of its own relations to 
 the environment, it is desirable, particularly in 
 the case of the nervous child, to guard against 
 meeting its complaints with an exhibition of un- 
 due sympathy. Undue egoism is the perennial 
 fault of the unstable mind, and this may begin 
 to show itself at a very early period. 
 
 The desire to attract attention at all hazards 
 is a symptom which should be 'regarded by the 
 parent with out and out solicitude. 
 
 A typical illustration of this desire carried to 
 an extreme is shown in the record of a girl who 
 is now the inmate of a reformatory institution. 
 The case is recorded by Miss Winifred Hathaway, 
 in a Bulletin of the Eugenics Record Office. 
 " From childhood this girl would do anything to 
 attract attention to herself. For instance, when
 
 Give Your Children a Chance 233 
 
 ' Jack the Snipper ' was cutting the hair of girls 
 in the streets of Boston, the patient caused a sen- 
 sation by cutting off her own hair. She hid it 
 and invented a thrilling story of her encounter 
 with the vandal, was delighted when brought to 
 court, and confessed only when confronted with 
 hair which had been found." 
 
 Not many children go quite so far as this, to be 
 sure, but exhibitions of the same general 
 character and import are matters of everyday 
 experience. 
 
 The wise parent will treat such craving after 
 sympathy and attention as evidence of mental and 
 moral instability. To cater to this craving is to 
 stimulate development in the wrong direction. In 
 the case of the girl just referred to, the failure 
 to repress this abnormal tendency permitted the 
 development of a character that was finally diag- 
 nosed as " deficient in any moral sense, incapable 
 of acquiring it, and requiring permanent custodial 
 care." The girl had so far degenerated at the 
 age of nineteen that the Binet-Simon test gave 
 her mental age at 11.4 years. Yet she had been 
 fairly good at her school studies at an earlier 
 age, reaching the eighth grade with no particular 
 difficulty. 
 
 The traits which in the young girl were charac- 
 terized as " wilfulness and quick temper," and 
 the egoism that manifested itself in the childish 
 trick of hair-cutting, had been permitted to de- 
 velop and to reach a culmination in immorality 
 and mental decadence.
 
 334 Adding Years to Your Life 
 
 Such a case conveys a warning which should 
 not be blinked at by the parent of any nervous 
 child whose craving for sympathy, undue sensi- 
 tiveness, and tendency to take offense at fancied 
 slights give evidence of its unhealthy egoism. Of 
 course, the hungry mind should not be embittered 
 by the absence of judiciously worded and sympa- 
 thetic approval on occasion, but wholesome re- 
 straint should be inculcated by the avoidance of 
 injudicious and indiscriminate praise; and every 
 effort should be made to restrain the eccentrici- 
 ties of such a child and to mold it toward the 
 normal, instead of fostering its peculiarities and 
 taking pride in its abnormalities as parents are 
 prone to do. 
 
 The Need of Sex Education 
 
 In recent years we have heard on all sides 
 reference to " sex hygiene " as a topic meriting 
 the careful attention of the educator. Until very 
 recently the subject was quite unheard of in this 
 connection. The reason for the change in the 
 public attitude is, presumably, that we have not 
 progressed very well under the hitherto prevailing 
 method of reticence. 
 
 The puritannical spirit of our forefathers made 
 the subject now implied by " sex hygiene " taboo 
 in all general discussions. But the undiscussed 
 subjects were in no wise subordinated, and the 
 spread of what is euphemistically described as 
 " white slavery," and of venereal diseases, with 
 their patent evils, served finally to convince a
 
 Give Your Children a Chance 235 
 
 large number of educators that we were not on 
 the right track. At Mannheim, in Germany, in 
 May, 1907, there was held a conference of sex 
 hygiene at which a discussion of the teaching of 
 sex in schools and colleges was participated in by 
 the most distinguished educators and physicians 
 in Germany. 
 
 There was a general concensus of opinion, ac- 
 cording to the report of Dr. Prince A. Morrow, 
 that sex should be taught in the secondary school 
 classes and the colleges and universities, and by 
 some it was urged that it should be taught in the 
 elementary schools. 
 
 * ' All agreed that while instruction in the origin 
 of life should be given in the home and at an early 
 age, the majority of parents were not qualified to 
 give it, and that the duty therefore devolved upon 
 teachers, and should be an integral part of the 
 course of study in all normal schools. 
 
 ' * In most of the states of Germany, courses of 
 sex pedagogy for advanced high school students 
 have been established. As these students are dis- 
 charged from school, they are enlightened by 
 medical lectures on the nature and peril of vene- 
 real diseases. There have also been established 
 lectures for parents in order to enable them to 
 deal intelligently with the sexual problem in the 
 education of their children. Somewhat similar 
 work is being done in France, and the teaching 
 of sex has been made mandatory in the Lycees 
 by the Minister of Public Instruction. 
 
 * ' In this country, a number of biological teach-
 
 236 Adding Years to Your Life 
 
 ers have, of their own initiative, inaugurated the 
 biological teaching of sex in high schools and 
 colleges. At the October meeting of the American 
 Society of Sanitary and Moral Prophylaxis, 
 papers were read by President Hall of Clark Uni- 
 versity and Professor Bigelow of Teachers 
 College, Columbia University, and discussed by 
 leading members of the Biological Teachers' Asso- 
 ciation. The opinion was freely expressed that 
 sex instruction forms an absolutely essential part 
 of a rational education, and that the benefits to 
 be derived from the biological teaching of sex 
 were so great that all opposition thereto was 
 bound to disappear. 
 
 11 The necessity of such teaching was held to 
 be too evident to be discussed. The question now 
 was one of matter and methods the facts to be 
 taught, the study of specific methods, the adapta- 
 tion to the age and mentality of the youth, and the 
 training of teachers in normal schools for this 
 important work." 
 
 The growth of the movement in this country is 
 further evidenced by the fact that the National 
 Federation for Sex Hygiene has for honorary 
 president that most distinguished of American 
 educators, President-Emeritus Charles W. Eliot 
 of Harvard. Under the auspices of this federa- 
 tion, a committee comprising Professor Thomas 
 M. Balliet, Dean of the New York School of Peda- 
 gogy, Professor Maurice A. Bigelow of Teachers 
 College, Columbia University, and the late Dr. 
 Prince A. Morrow, formulated a plan for sex edu-
 
 Give Your Children a Chance 237 
 
 cation, and secured the opinions of a large number 
 of prominent educators and medical men. 
 
 The report of these investigators was presented 
 before the sub-section on sex hygiene in the Fif- 
 teenth International Congress on Hygiene and 
 Demography, held in Washington, in 1912, and 
 was subsequently issued as a pamphlet for gen- 
 eral distribution. 
 
 Thirteen propositions, covering the essential 
 aspects of sex education were submitted to the 
 educators and medical men whose opinions were 
 sought, and the almost unanimous response left 
 no possible doubt as to the present tenor of opin- 
 ion as to the ' ' need of special instruction of young 
 people in the scientific principles of sex." 
 
 As to that fundamental proposition, indeed, 
 there were 91 responses in the affirmative, as 
 against no negatives and only 5 expressions of 
 doubt. 
 
 In expressing his own belief in the need of such 
 instruction, the Rev. Josiah Strong, President 
 of the American Institute of Special Service, made 
 the following statement: " Inquiries made more 
 than fifteen years ago, in New England, Minne- 
 sota, California, and in thirty cities of Pennsyl- 
 vania, all revealed a shocking condition among 
 children, indicating great need of sex instruction ; 
 and the answer to 2,000 letters of inquiry sent 
 eighteen months ago to school superintendents and 
 principals in all the States of the Union confirmed 
 the judgment." 
 
 Professor Peter Frandsen, of the University
 
 238 Adding Years to Your Life 
 
 of Nevada, described the need of such instruction 
 as fourfold: " (a) Hygienic and eugenic better 
 sex health and better progeny; (b) The control 
 of venereal diseases; (c) To save young people 
 from needless mental disturbances over normal 
 sexual phenomena, and to save them from the im- 
 positions of quackery; (d) To change the attitude 
 from the present one of total avoidance, or a sub- 
 ject fit only for lewd conversation, to one of serious 
 respect." 
 
 Sex Education Must Begin Early 
 
 Dr. Balliet's report expressly recognizes the 
 fact that the " less children and youth think of 
 sex, and the later they mature sexually, the better 
 for them both physiologically and ethically; and 
 that premature development of the sex conscious- 
 ness and the sex feelings is harmful." 
 
 But it also recognizes that the subject cannot be 
 banished from the world of the child, and that 
 there is peculiar danger that the child will receive 
 sex information from impure sources. It empha- 
 sizes the need of very early instruction. Even as 
 regards social disease, it is declared that " some 
 direction of individuals is sadly needed by many 
 children in the two or three pre-adolescent years ; 
 and it is to be hoped that every school will finally 
 have one or more competent persons (principal, 
 nurse, doctor, or teacher) able to deal effectively 
 with the individuals needing help." 
 
 President Arthur H. Wilde, of the University 
 of Arizona, declares that " in all towns and cities
 
 Give Your Children a Chance 239 
 
 many of the children, even in the best families, 
 have started down even before the age of ten. 
 A very necessary activity is the study of the chil- 
 dren's home surroundings ; and it is also necessary 
 to convince parents that children, at an early age, 
 may have wrong notions and incipient vices." 
 And as to smaller centres of population, Principal 
 G. L. Bowman, of the Training School for Teach- 
 ers, at Menomonie, Wisconsin, affirms that much 
 damage is done to boys at a very early age by 
 what he describes as " the tramp woman." 
 
 But it is further urged that the child needs at- 
 tention not merely during adolescent and pre-ad- 
 olescent years, but even during infancy. In point 
 of fact it is true that in very many cases the im- 
 proper sex education which is to shape the entire 
 moral life of the individual is inadvertently gained 
 in infancy. Every experienced specialist could cite 
 cases of ineradicable perversion, directly trace- 
 able to influences to which the child was subject 
 when not more than three or four years of age. 
 
 Hence the pertinency of the admonition given 
 by Dr. Balliet and his colleagues with reference 
 to the care of the child during this earliest period. 
 
 " The period from one to six," says the report, 
 " is the period preceding admission to school, and 
 is, therefore, the only period during which the care 
 of the child falls chiefly upon the mother the 
 kindergarten at present reaching only a small 
 proportion of children. It is, therefore, impor- 
 tant that in lectures on sex education given to 
 mothers, special emphasis be laid upon this period,
 
 240 Adding Years to Your Life 
 
 and that proper instruction be given as to the care 
 of the child's body. The danger to the child of 
 placing it in the care of an immature or inju- 
 dicious nurse should be pointed out. Instruction 
 should be given as to how the child's questions 
 relating to the origin of human life may best be 
 answered. This is the only sex instruction a child 
 needs during this first period. In addition to this, 
 watchfulness over the child's habits, and protec- 
 tion from untoward influences constitute the 
 mother's chief duty." 
 
 But this " watchfulness over the child's habits," 
 implies far more than most parents realize. As 
 Dr. Morrow urges, the foundations of what may be 
 called the sexual character are laid in early youth ; 
 and " the ideals and principles instilled in this 
 formative period are apt to determine the attitude 
 toward sex and the sex relation throughout life." 
 
 " Many parents," says Dr. Morrow, " are silent 
 because they fear to soil the ' crystal purity of the 
 youthful mind ' with a thought or suggestion of 
 anything so shameful as sex. If ignorance were 
 a preservative of innocence, if their silence 
 shielded youth from sexual errors, it might be 
 justified. But there is nothing more fatuous than 
 the belief that they succeed. The objection urged 
 by some that sex education would stimulate an un- 
 healthy curiosity, and focus the imagination upon 
 sexual matters, is scarcely more valid. Curiosity 
 about the origin of life and sex already exists ; it 
 is implanted by nature. If it is not satisfied from 
 pure sources it will be fed from impure and tainted
 
 Give Your Children a Chance 241 
 
 sources. It must be the pure wholesome education 
 of the home or the corrupt teaching of the streets ; 
 there has been no alternative." 
 
 Idealizing the Sex-Relation 
 
 It is deplorable that the majority of parents are 
 but poorly qualified to give their children specific 
 instruction of the right kind at the later periods 
 of development. 
 
 It is urged that, to meet this defect, systematic 
 courses of lectures for parents should be provided 
 at public expense. President H. A. Garfield, of 
 Williams College, suggests that following the lec- 
 tures to parents only, it may be well to arrange 
 a course of lectures to parents accompanied by 
 their children. This, he declares, would tend to 
 establish mutual confidence between parent and 
 child. 
 
 Until this excellent advice can be generally put 
 into effect, it remains the duty of the professional 
 educators to supply the instruction which the aver- 
 age home cannot give. The admirable suggestions 
 as to details of such instruction, which Dr. Balliet 
 and his colleagues put forward with the approval 
 of almost one hundred of the leading educators 
 of America, need not be elaborated here. Suffice 
 it that great stress is laid on the value of biological 
 training through which the fundamental facts of 
 development are presented in their broadest as- 
 pects. 
 
 But it is urged that the purely scientific instruc-
 
 242 Adding Years to Your Life 
 
 tion must be reinforced by ethical instruction, both 
 direct and indirect, with due regard to the matur- 
 ity of those taught. " Appeals to the sense of 
 personal self-respect and purity and to the instinct 
 of chivalry can be effectively made in the earliest 
 years of adolescence, and even before. With rela- 
 tively mature students, the vast sociological 
 bearings of the subject, with their ethical implica- 
 tions, can be effectively utilized. 
 
 " Among the means of indirect ethical instruc- 
 tion for this purpose, the most effective is good 
 literature. It is of immense consequence that 
 during the adolescent years the pupils' minds be 
 saturated with the great masterpieces, both in 
 poetry and prose, which deal with romantic love 
 in its purest forms. Thought of sex emotion must 
 at this time be spiritualized and placed on the 
 highest plane, and good literature is the most 
 effective means to this end which is available in 
 the public schools. Any kind of sex education 
 which ignores the education of the emotions is 
 seriously defective. Deep intellectual interests, 
 enthusiasm in art, or ardent devotion to some 
 worthy, practical cause, absorb the mind and fur- 
 nish wholesome avenues for the expression of 
 the emotions. 
 
 " Few conditions are so dangerous at this 
 period as idleness, whether physical or mental, 
 and an absence of interest in things which appeal 
 to the higher altruistic instincts." 
 
 Yet another aspect of sex education is recog- 
 nized in this declaration : * ' The value of physical
 
 Give Your Children a Chance 243 
 
 exercise, especially in the form of play and ath- 
 letic sport, in its bearing on the control of the sex 
 instinct, is so generally recognized that it needs 
 no special emphasis here." 
 
 To parents who, under spell of the old ideas, are 
 disposed to question the advisability of attempt- 
 ing to break down the barriers of reticence that 
 have hitherto surrounded this subject, the con- 
 cluding paragraph of Dean Balliet's report may 
 be especially commended : 
 
 " In conclusion, your Committee would empha- 
 size the necessity of good judgment and tact in 
 introducing sex instruction into schools. It should 
 not be introduced prematurely, but only so fast 
 as teachers can be found or trained who are compe- 
 tent to give it, and so fast as public sentiment will 
 support it. On the other hand, undue weight must 
 not be given to the difficulties attending such in- 
 struction even under present conditions, inasmuch 
 as even occasional mistakes will do far less harm 
 than allowing children to continue to gain this 
 knowledge, as many of them now do, from impure 
 sources receiving a pernicious first impression 
 which induces in them an attitude of mind toward 
 the subject that makes it extremely difficult later 
 to give them the best instruction. In not a few 
 such cases sound teaching is practically fruitless." 
 
 And this may be supplemented by an expression 
 made by Professor Bigelow, in another connection, 
 where he says : 
 
 11 Now unless we can devise some way to 
 counteract the prevailing narrow, vulgar, disre-
 
 244 Adding Years to Your Life 
 
 spectful, and irreverent attitude towards all 
 aspects of sex and reproduction; unless we can 
 make people see sexual processes in all their nor- 
 mal aspects as noble, beautiful, and splendid steps 
 in the great plan of nature ; unless we can substi- 
 tute a philosophical and esthetic view of sex 
 relationship for the time-worn interpretation of 
 everything sexual as inherently vulgar, base, ig- 
 noble, and demanding asceticism for those who 
 would reach the highest spiritual development; 
 unless we can begin to make these changes in the 
 prevailing attitude towards sex and reproduction, 
 we cannot make any decided advance in the 
 attempt to help solve sex problems by special 
 instruction." 
 
 " I cannot believe," Professor Bigelow con- 
 cludes, " that sex education is one of the long line 
 of educational fads which quickly pass their day, 
 for no other phase of education so closely touches 
 life. History and geography and even a large 
 part of the three R's may be of little use in the 
 lives of numerous people, but sex education deals 
 with problems which the normal human life can- 
 not possibly avoid and which each individual must 
 be prepared to solve for himself. Therefore, we 
 may confidently assert that scientific instruction 
 concerning the most important aspects of sex 
 processes and relationships has come to stay, and 
 that it will soon be recognized as an absolutely 
 necessary part of a rational and efficient scheme 
 for the education of young people."
 
 IX 
 
 Adding Years to Your Life 
 
 TPVO you know how old you are? 
 **^ The question sounds absurd but is not. Of 
 course you know when you were born ; but are you 
 sure you know how fast you have lived? Age is 
 not measured solely by birthdays. It is far more 
 surely measured by the state of your arteries. 
 These may be elastic and resilient, in which case 
 you are young, whatever your years ; or they may 
 be hard and brittle, in which case you are old, how- 
 ever short the time since you were born. 
 
 You may in reality be thirty-five or forty years 
 old, while your neighbor is properly to be spoken 
 of as seventy or seventy-five years young. 
 
 The difference is that your neighbor has learned 
 the secret of right living, whereas you, if old at 
 forty, are probably poisoning yourself daily with 
 the food that you eat. 
 
 Perhaps you are not even aware that common 
 foods may become poisonous to you under certain 
 conditions. Quite possibly you have no clear no- 
 tion as to the precise quantities of meat and other 
 foods that your system requires day by day. Yet, 
 if you eat too much nitrogenous food, the bad ef- 
 fects will make themselves felt on your arteries, 
 
 245
 
 246 Adding Years to Your Life 
 
 and you will age in reality by two or three years 
 with each successive birthday. 
 
 Proteid (meat) poisoning makes brittle arteries; 
 and a man with brittle arteries has the sword of 
 Damocles hanging with perpetual menace over 
 his head. 
 
 Hundreds of thousands of people are thus men- 
 aced, as the death rolls from " apoplexy," " heart 
 failure," " paralysis," and sundry diseases of 
 liver and kidneys prove day by day. 
 
 Do you know whether you are thus menaced ? If 
 not, it is worth your while to find out. 
 
 The alarming prevalence of this condition of 
 arterial degeneration gives peculiar importance 
 to a report read at a meeting of the Paris Academy 
 of Medicine last May by Professor Letulle. The 
 report concerns the remarkable work done there 
 in recent months by Dr. Moutier in the way of 
 treatment of diseases of the arterial system with 
 the high-frequency electric current. It was re- 
 ported that Dr. Moutier has succeeded in a large 
 number of cases in restoring diseased arteries to 
 a normal condition, thus giving a normal blood 
 supply to the tissues. 
 
 Every organ of the body may suffer from dis- 
 eased conditions of the arteries; which explains 
 the report that the new treatment has been applied 
 to the amelioration of a multitude of disorders 
 affecting not merely the heart and vascular mech- 
 anism in general but various abdominal organs, in- 
 cluding the liver and the kidneys. 
 
 It is highly interesting to add that almost simul-
 
 Adding Years to Your Life 247 
 
 taneously the report comes from Berlin that Dr. 
 Saubermann has accomplished similar results by 
 treating diseased arteries with radium. 
 
 These discoveries deal with a subject of pro- 
 found importance. In 1910 more than 100,000 
 persons died in the United States from diseases 
 of the circulatory apparatus. The aggregate death 
 roll of typhoid fever, malaria, smallpox, measles, 
 scarlet fever, whooping-cough, diphtheria, influ- 
 enza, and several minor bacterial diseases was only 
 59,000. 
 
 Thus the diseases of the heart and blood vessels 
 were directly responsible for almost twice as many 
 deaths as were due to an entire coterie of much- 
 dreaded contagious diseases. 
 
 We hear on all sides an outcry against the great 
 white plague, and the whole world is eagerly 
 awaiting the discovery of a cure for cancer. Yet 
 tuberculosis causes the death of only 160 persons 
 per 100,000 of the population, and cancer and other 
 malignant tumors claim only 76, as against 185 
 who fall victim to diseases of the circulatory 
 system. 
 
 Moreover, there are many degenerative mala- 
 dies affecting other vital organs that are inaugu- 
 rated by or dependent upon disturbances of the 
 blood supply; and these degenerative diseases 
 affecting the heart, blood vessels, kidneys, and 
 other vital organs are very actively on the in- 
 crease. It is computed that the death-rate from 
 this class of diseases per 100,000 of the population 
 was 190 in 1880, that it advanced to 243 in 1890,
 
 248 Adding Years to Your Life 
 
 to 314 in 1900, and to 387 in 1908; thus more than 
 doubling in the course of a single generation. 
 
 This explains why the life insurance examiner 
 nowadays pays such exceptional attention to the 
 state of your heart and kidneys. He knows that 
 there is more than an even chance that you are 
 not altogether normal as regards these vitally im- 
 portant organs. 
 
 It appears, then, that while medical science has 
 been combating the microbes and decreasing infant 
 mortality, it has tended to overlook the average 
 middle-aged person. He is dying in larger and 
 larger numbers of degenerative diseases. A re- 
 cent report of the Department of Health shows 
 that the " expectancy " of life after forty has 
 diminished by fifteen years for males and by 
 eighteen for females within the present genera- 
 tion. Your father and mother, at forty, had a far 
 better prospect of living to a green old age than 
 you have to-day. And the alarming change is 
 closely connected with errors of diet that lead to 
 degenerative changes of the arteries; changes 
 which have hitherto been considered incurable, but 
 which, according to the reports from Paris and 
 Berlin, may now be brought within the scope of 
 remedial treatment. 
 
 But while great interest and importance thus 
 attach to the possible restoration to the normal 
 of arteries that have become diseased, it should 
 go without saying, in this age of preventive medi- 
 cine, that a still greater importance attaches to the 
 question : How can we prevent the arteries from
 
 Adding Years to Your Life 249 
 
 becoming diseased ? Here as elsewhere prevention 
 is far better than cure. 
 
 And it fortunately happens that these maladies 
 are pre-eminently preventable. 
 
 In the main they are brought on by habits of life 
 that might readily be changed. It is scarcely an 
 exaggeration to say that the great bulk of the 
 100,000 people who die prematurely each year in 
 this country of diseases of the vascular system 
 have been so directly responsible for shortening 
 their own lives that they might not inappropri- 
 ately be described as involuntary suicides. 
 
 It should be of interest to you and me to inquire 
 whether we, individually, are likely to add our 
 names to the list. 
 
 Poisons in Our Daily Meat 
 
 One of the most striking conclusions to which 
 recent investigators have come is that a very large 
 proportion of people who have reached middle life 
 have acquired habits of eating that are directly 
 injurious, and that subject their systems to a slow 
 poisoning that in effect hastens old age and ulti- 
 mately brings death itself. 
 
 There is nothing new in the statement that most 
 people eat too much. But the new investigators 
 go beyond this and point out the precise kinds of 
 food that produce particular types of injury. They 
 tell us that a great number of persons who have 
 passed middle life have accustomed themselves to 
 a diet that includes an excess of proteids, that is
 
 250 Adding Years to Your Life 
 
 to say, of foods that contain nitrogen, of which 
 prominent examples are eggs and all kinds of 
 meats. 
 
 " Protein," says Dr. L. F. Bishop of New York, 
 " is very important in building up the tissues, 
 strengthening the muscles, and stimulating the 
 activity of the brain and the emotions. It is the 
 food that produces great leaders and brain work- 
 ers, but it is also a food that in the present day is 
 terminating prematurely some of the best lives in 
 the nation." 
 
 The specific explanation given by Dr. Bishop of 
 this rather alarming statement is based on a long 
 series of observations in which laboratory work 
 has joined hands with clinical experience. This 
 work has to do with a condition of the organism 
 which the specialist terms * * anaphylaxis. ' ' Stated 
 untechnically, this means a curious susceptibility 
 to a particular food or medicine. Such so-called 
 idiosyncrasies have been known in a general way 
 from the earliest times. It. is traditional that 
 " what is one man's food is another's poison." 
 But the scientific investigation of the matter is 
 altogether modern. A pioneer in the field is Pro- 
 fessor Victor C. Vaughan, who tells in a recent 
 number of The American Journal of Medical Sci- 
 ence of some curious instances in which ordinary 
 foods may become poisons to particular indi- 
 viduals. 
 
 For example, an individual may become sus- 
 ceptible to the poisonous properties of the protein 
 of egg or of fish, or of beef or mutton. The in-
 
 Adding Years to Your Life 251 
 
 dividual in whose system this undue sensitiveness 
 has developed may be quite unconscious of his 
 infirmity. Indeed, the food that particularly poi- 
 sons him may be one of which he is especially fond. 
 So he continues to take it in large quantities and 
 is steadily and persistently poisoned. The effects 
 are not immediately obvious in a marked degree, 
 but the cumulative result is finally apparent in the 
 degeneration of many tissues, leading ultimately 
 to a marked disturbance of function of such all es- 
 sential organs as the heart and vascular system, 
 the liver, and the kidneys. 
 
 It is this that Dr. Bishop has in mind when he 
 assures us that slow poisoning by protein accounts 
 for a very large number of deaths. He believes 
 that the typical malady of middle life known as 
 arterio-scelerosis, or hardening of the arteries, is 
 due to systematic poisoning from the habitual in- 
 gestion of foods to which the particular individual 
 has become unduly sensitized. In his judgment 
 there are hundreds of thousands of people, mostly 
 above the age of forty, who are daily jeopardizing 
 their health and inducing premature senility with 
 ultimate shortening of life. 
 
 These facts should be known to and pondered 
 by every individual who has reached middle life. 
 But how, practically speaking, may you and I 
 know whether we are poisoning ourselves? In or- 
 der to answer that question we must get a clear 
 idea of the conditions under which that strangest 
 of mechanisms, our own body, operates in health 
 and in disease.
 
 252 Adding Years to Your Life 
 
 The Animal Machine 
 
 It is only in comparatively recent times that we 
 have come to understand that the bodily mechan- 
 ism is a machine subject to laws that apply to all 
 types of machinery. 
 
 It is a mechanism that cannot work without ex- 
 hausting or transforming energy. Even when the 
 body is at rest there is still constant loss of energy 
 through the giving off of heat. It has become cus- 
 tomary to think of the animal machine as a heat 
 engine and to measure its activities in terms of so- 
 called calories ; a calory being the amount of heat 
 required to raise a kilogram of water (a little over 
 a quart) by one degree Centigrade. The aggre- 
 gate amount of energy utilized by the human body 
 in a day may vary, according to the size of the 
 individual and degree of activity, from 2,000 to 
 8,000 or even 10,000 calories. 
 
 The materials oxidized or burned in the body to 
 generate this energy are supplied by the food. 
 
 Did you ever stop to consider what a marvel it 
 is that your body is able to conserve heat when 
 heat is needed and eliminate an over-supply, using 
 always just the right amount of fuel and keeping 
 in perfect running order if given half a chance I 
 
 You are out in the open on a winter day, drawing 
 deep breaths of air at a temperature, say, 10 de- 
 grees below zero. Every inhalation draws frigid 
 air into your lungs, and each exhalation carries 
 from your body a modicum of heat. But your 
 bodily heat-engine burns fuel with such nice ad-
 
 Adding Years to Your Life 253 
 
 justment to your needs that your temperature re- 
 mains hour after hour at 98.4 degrees Fahrenheit. 
 
 Six months later you are walking under a tropic 
 sun, the thermometer registers perhaps 90 degrees 
 in the shade, and the air you breathe seems to come 
 from a furnace. But your bodily temperature now 
 as before is 98.4 Fahrenheit. 
 
 If you suddenly jump about or run briskly, you 
 in effect put a bellows to the bodily furnace. Your 
 heart beats faster; your breath comes in gasps; 
 and judging by your own feelings you have made 
 your blood almost boil. But meantime the blood 
 vessels lying at the surface of your body have re- 
 laxed, and the blood thus brought to the surface 
 radiates heat into the surrounding space, and thus 
 cools your body as a whole in spite of your feeling 
 of warmth ; and this cooling is greatly aided by the 
 perspiratory glands with which your skin is thickly 
 provided, which now ooze water, exuded from the 
 blood, which in evaporating takes up a relatively 
 enormous amount of heat. 
 
 The skin thus performs for the body the service 
 done by the water-jacket in an automobile engine. 
 
 But it ie obviously essential for the proper work- 
 ing of this wonderful heat regulator that the blood 
 vessels should be elastic and resilient, responsive 
 to the mandates of the nervous mechanism. Nor 
 can we expect ideal conditions if the body is con- 
 stantly called upon to consume a needless supply 
 of fuel and thus to generate an undue quantity of 
 heat. Under such circumstances, the excretory 
 channels become clogged with waste products, just
 
 254 Adding Years to Your Life 
 
 as the carburetor and cylinder of a gasoline motor 
 become clogged if too much gas is supplied or an 
 improper admixture of gas and air. 
 
 You are well aware that your automobile engine 
 will not work without proper fuel. Neither will 
 your bodily engine. 
 
 The automobile mechanism quickly wears out 
 and becomes ineffective if the conditions essential 
 to its well-being are not maintained. So does the 
 bodily mechanism. 
 
 If you are wise you will take at least as good 
 care of your bodily machine as you do of your 
 gasoline motor. You can buy another automobile 
 if your present one wears out; but you have the 
 use of only one body in this life, and no opportu- 
 nity will ever be given you "to do better next 
 time." 
 
 Fuel for the Bodily Engine 
 
 Let us ask, then, a little more specifically, just 
 how it may be known whether you, individually, 
 are supplying your bodily machine with the right 
 kind and right quantities of fuel. 
 
 The chemists tell us that notwithstanding the 
 great variety of foodstuffs, they may all be classi- 
 fied under three headings. Foods are either pro- 
 teins, or fats, or carbohydrates. Fats and carbo- 
 hydrates consist of carbon, hydrogen, and oxygen ; 
 protein contains the same elements with the ad- 
 dition of nitrogen. 
 
 The familiar carbohydrates are starches and 
 sugars in their various combinations.
 
 Adding Years to Your Life 255 
 
 The proteins are supplied by meats of all kinds, 
 and by milk, cheese, and eggs. There is also pro- 
 tein in bread, and a relatively high percentage in 
 leguminous vegetables such as beans and peas. 
 
 All three classes of food products supply fuel 
 to be oxidized or burned in the system. But there 
 is a very radical additional function subserved by 
 the proteids, or nitrogenous foods. These supply 
 nitrogen to take the place of that which is con- 
 stantly set free in the action of muscular tissue 
 and eliminated from the body. The bodily ma- 
 chine immediately begins to run down if the nitro- 
 gen-bearing proteids are withheld or the supply is 
 insufficient in quantity, and no amount of fats or 
 of carbohydrates can make up the deficiency. 
 
 But on the other hand, as we have seen, the same 
 proteins if supplied in excess or of improper qual- 
 ity may be the undoing of the bodily mechanism. 
 So here we are placed between the devil of too 
 little nitrogen and the deep sea of too much. We 
 cannot live without the nitrogen, and if we are 
 not careful we shall find that we cannot live with 
 it. Obviously, the situation demands a compro- 
 mise. 
 
 What Meat Is Your Poison? 
 
 The practical solution is found in the facts that 
 (1) we know how much proteid matter the organ- 
 ism requires in a day, and (2) we know that cer- 
 tain classes of proteids are under suspicion as 
 producers of degenerative changes of the blood 
 vessels and vital organs. Your individual task,
 
 256 Adding Years to Your Life 
 
 then, is to make sure that your dietary includes 
 proteids in adequate quantity (but not greatly in 
 excess) and that deleterious proteids are excluded. 
 
 You perhaps suffer now and again from head- 
 aches and neuralgias. You may be rheumatic or 
 gouty. You are subject to attacks of biliousness ; 
 are easily fatigued; lack energy and initiation of 
 mind and body; find yourself short of breath on 
 walking briskly or on going upstairs. At times 
 your heart palpitates unduly. 
 
 These are all symptoms that suggest disturbed 
 assimilation. 
 
 The first question to ask yourself is this: Is 
 there any food that I am accustomed to take habit- 
 ually that is poisonous to me? It is quite possible, 
 according to the newest theories above outlined, 
 that your regular diet may include something that 
 to you individually is toxic, yet which is altogether 
 wholesome to people in general and even to mem- 
 bers of your own family. 
 
 The obvious way to test the matter, if you have 
 any doubt at all on the subject, is to cut out one 
 or more of these questionable foods from your 
 dietary for a given period, and note the results. 
 The proteids that are most under suspicion are 
 those contained in the animal albumens meats of 
 all kinds, including fish, and eggs and in such 
 leguminous vegetables as peas and beans ; and the 
 uric-acid forming constituents of tea and coffee. 
 In making a radical test, all these should be 
 avoided. 
 
 It is unquestionable, however, that you may be
 
 Adding Years to Your Life 257 
 
 suffering from a slow poisoning due to deleterious 
 food without experiencing any symptoms that you 
 associate directly with your diet. Your arteries 
 may be gradually hardening week by week, with- 
 out producing any sensation that arouses your 
 suspicion. About the only way to put the matter 
 to a crucial test is to go to your physician and 
 have him measure your blood pressure. It is now 
 recognized that increased blood pressure is one of 
 the earliest symptoms of proteid poisoning. 
 
 The physician is provided with several appli- 
 ances by which the pressure may be tested, and is 
 able to offer timely warning to many a middle- 
 aged person who supposed himself to be in fairly 
 good health, or who as yet has only vague premo- 
 nitions of his malady. 
 
 What the Blood Pressure Shows 
 
 Altered blood pressure may be due to the con- 
 dition of the heart itself or to changed resiliency 
 of the arteries and capillaries through which the 
 blood courses. 
 
 But recent studies strongly suggest that the 
 initial condition in a great number of cases per- 
 haps in all cases is an abnormality of the blood 
 itself. Recent experiments tend to confirm the 
 claims of the London specialist, Dr. Alexander 
 Haig, that where high blood pressure is found, the 
 blood is always unduly viscous and tends to be- 
 come clogged at the minute apertures of the capil- 
 laries. The famous English physician, Sir Lauder
 
 258 Adding Years to Your Life 
 
 Brunton, recently reported a case in which there 
 was such viscosity that scarcely any blood flowed 
 even when a vein was opened. 
 
 The thickening of the blood which thus disturbs 
 the circulation, and which is premonitory of dis- 
 aster, may be due to the ingestion of unwholesome 
 foods or merely to the ingestion of an excessive 
 quantity of wholesome ones. Thousands of men 
 and women of sedentary habits have accustomed 
 themselves to a daily regimen, including some such 
 combination of proteids as the following: At 
 breakfast, two eggs and a slice or two of bacon; 
 at lunch, a cup of bouillon, mutton chops or a slice 
 of beef, green peas, and a portion of cheese; at 
 dinner, a long series of proteids, including oysters 
 or clams, soup, fish, fowl, and a red meat. 
 
 Such a dietary is utterly abnormal and must 
 inevitably lead to disaster. 
 
 No one but a laboring man or an athlete in full 
 training could with impunity eat regularly even 
 small portions of such a variety of proteids. And 
 no wisely trained athlete would think of under- 
 taking such a feat. The most powerful athletes 
 that I have personally examined eat meat only 
 once a day, and a good many of them habitually 
 take but two meals, breakfast comprising a roll and 
 one egg or at most two, and dinner having for its 
 chief proteid never more than a single kind of 
 meat, and a moderate portion of that. 
 
 Such is the custom, for example, of George Both- 
 ner, perhaps the most remarkable athlete of our 
 generation, who at 46 is boyish in face and figure
 
 Adding Years to Your Life 259 
 
 and who, after holding the world championship for 
 more than ten years, is still invincible to any 
 wrestler of his own weight. 
 
 Eating to Live 
 
 If your habits are sedentary, you obviously re- 
 quire less food than the athlete in training. 
 
 So it is more than likely that you eat not merely 
 more protein but a great deal more food of every 
 kind than is good for you. Not unlikely you con- 
 sume daily twice as much food as your bodily ma- 
 chine can advantageously manage. 
 
 It is estimated that the man of average size who 
 does little physical work requires not more than 
 50 to 60 grams of protein, say about two ounces. 
 We may gain a clear idea as to the amount of food 
 that will provide this if we note the following esti- 
 mate made by Dr. Bishop : 
 
 ' ' Roughly speaking, but with sufficient accuracy 
 for practical purposes," he says, " an average 
 helping of meat contains 25 grams of protein, or to 
 be more accurate, a cubic inch of beefsteak, beef, 
 or fish contains 8 grams ; an egg contains 8 grams, 
 as does also a glass of milk. An ordinary helping 
 of rice, potatoes, bread, or hominy contains about 
 4 grams of protein." 
 
 If, then, you were to take two eggs for break- 
 fast, a glass of milk or a cup of bouillon at lunch, 
 and a moderate helping of beef (say a piece of 
 steak three inches long and one inch thick) at din- 
 ner, you have consumed a quantity of protein ade-
 
 260 Adding Years to Your Life 
 
 quate for the day's needs. And this without at all 
 taking into consideration the protein contained in 
 the bread, potatoes, rice, beans, peas, pudding, and 
 soup that have rounded out your meals for that 
 day. 
 
 Obviously you are a very moderate eater indeed 
 if you do not ingest an excessive quantity of pro- 
 tein. 
 
 As to the total food supply measured in heat 
 units, it is estimated that a man doing light work 
 requires about sixteen calories ' of energy per 
 pound of weight. A man weighing 170 pounds 
 would therefore require about 2,500 calories. It 
 is further computed that each ounce of proteid 
 food supplies the body about 113 calories ; and an 
 ounce of carbohydrates also supplies 113 calories ; 
 and an ounce of fat about 255 calories. So a 
 dietary comprising about 2l/> ounces of proteids, 
 and similar quantities of fats, and 14 ounces of 
 carbohydrates would supply the daily needs of a 
 man weighing 170 pounds. 
 
 This is less than 114 pounds of digestible mat- 
 ter. But of course there is an unavailable resi- 
 due in most foods, so the actual quantity ingested 
 would be considerably larger. An average day's 
 supply of food for a man of 170 pounds might be 
 apportioned as follows : To supply proteids, one 
 egg, one pint of milk, one ounce of cheese, 6 ounces 
 of meat (weighed before cooking) ; to supply fats, 
 2 ounces of butter (plus a certain amount of fats 
 in the other articles of diet) ; to supply carbohy- 
 drates, 8 ounces of bread or equivalent bread
 
 Adding Years to Your Life 261 
 
 stuffs, 4 ounces each of potatoes, spinach, and 
 tapioca, and 2 ounces of sugar. This represents 
 an adequate fuel supply for a good-sized man of 
 fairly active physical habits. 
 
 By experimenting a little with a pair of scales, 
 you may quickly satisfy yourself as to whether or 
 not your own dietary represents a reasonable fuel 
 supply, or whether, as is probable, you are accus- 
 tomed to take an amount of food a good deal in 
 excess of your requirements. In the latter case, 
 you will do well to recall that an excess of fuel 
 must tend to clog the working of the bodily ma- 
 chine, bringing an undue strain upon the digestive 
 and circulatory systems, thickening the blood, and 
 overtaxing those all-important excretory organs, 
 the kidneys. 
 
 Also you may quite likely have observed that a 
 certain amount of the excess fuel tends to be 
 stored away as adipose tissue, which becomes 
 presently a serious encumbrance. 
 
 You must squarely face the question whether 
 you will live to eat, pampering your appetite and 
 risking the consequences, or whether you will eat 
 to live, making a rational selection of food, and 
 exercising a wise restraint as to the quantity in- 
 gested. 
 
 If you find it difficult to resist the allurements 
 of the table, the classical experiment of Professor 
 Chittenden of Yale may helpfully be recalled. In 
 his personal experience, not only did rheumatism, 
 " sick headache," and biliousness disappear when 
 a carefully computed restricted diet was adhered
 
 262 Adding Years to Your Life 
 
 to, but " there was a greater appreciation of such 
 food as was eaten, a keener appetite and more 
 acute taste seemed to be developed, with a more 
 thorough liking for simple foods." 
 
 So adherence to a rational dietary by no means 
 implies the renunciation of all pleasure in eating. 
 
 Exercise the Sovereign Remedy 
 
 But however abstemious your diet, you cannot 
 hope to keep your bodily machine in good working 
 order unless you give some attention to the ob- 
 verse side of the question of digestion and nu- 
 trition ; that is to say, to the matter of bodily exer- 
 cise. No discussion of longevity would be in any 
 sense complete that left this out of consideration. 
 
 The case of the athlete who retains the resiliency 
 and strength of youth at fifty or sixty years of age 
 to say nothing of a Weston who walks across the 
 Continent at seventy-two conveys a double les- 
 son. Not only has such a person been rationally 
 abstemious in his diet, but he has aided nature in 
 maintaining a healthy condition of his bodily 
 mechanism by giving all portions of that mech- 
 anism an opportunity to functionate normally. 
 Which is only another way of saying that he has 
 habitually exercised his muscles. 
 
 In so doing he has given tone to his heart and 
 arteries by stimulating a normal circulation of the 
 blood, and at the same time has facilitated the 
 elimination of waste products. 
 
 Thus at sixty he may have an organism which,
 
 Adding Years to Your Life 263 
 
 judged by the condition of its vital tissues, is no 
 nearer the final breakdown no older, to use the 
 conventional phrasing than the system of the 
 average gourmand of sedentary habits who, by 
 count of birthdays, is twenty years younger. 
 
 Action of the muscles results in a more rapid 
 metabolism of the tissues, accompanied by an in- 
 creased burning of fuel. The contracting muscles 
 directly promote the flow of the blood-stream in 
 the veins and in the capillaries, thus tending to 
 lower the arterial pressure. With bettered circu- 
 lation, the perspiratory glands become active, and 
 some of the products of combustion are eliminated 
 by way of the skin. If your kidneys are not able 
 to handle the waste products of the body with facil- 
 ity, this is highly important. 
 
 Of course games and sports that develop an in- 
 terest are in every way better than mere per- 
 functory exercises. 
 
 Tennis, golf, baseball, hockey, and basket-ball 
 are excellent, each in its own way. So are rowing, 
 swimming, and riding. In default of anything 
 better, brisk walking will serve a useful purpose; 
 while mountain climbing for those whose hearts 
 are in good order has many advantages. 
 
 The indoor games that afford the best all-round 
 exercise are handball and court tennis. Wrestling, 
 boxing, fencing, and bowling are all-round devel- 
 opers of muscle that partake also of the elements 
 of recreation, and in a less degree the same thing 
 is true of ' * punching the bag ' ' and throwing the 
 * ' medicine ball. ' ' Perhaps no single form of gym-
 
 264 Adding Years to Your Life 
 
 nasium sport combines so many advantages for 
 persons past middle age as the game of handball. 
 This gives vigorous exercise without inducing un- 
 due strain, and it brings into play every muscle 
 in the body. 
 
 For persons in good condition, wrestling is an 
 almost incomparable exercise; but it should only 
 be undertaken as the sequel of a course of lighter 
 training. 
 
 Whatever the form of exercise, it should be pur- 
 sued with sufficient vigor to stimulate the heart's 
 action, ensure deep breathing, and so increase the 
 heat-producing activities of the tissues that the 
 blood will be brought to the surface, the skin made 
 to glow, and the perspiratory glands stimulated to 
 free action. The latter effect may be further fa- 
 cilitated by a few minutes in a hot room or the 
 equivalent, the " Turkish bath cabinet "; this to 
 be followed with a shower bath, warm at first but 
 toned gradually to the coldest degree from which 
 the body will react. 
 
 The cold shower is doubly important because it 
 not only closes the pores of the skin and obviates 
 the danger of taking cold, but also acts as a gen- 
 eral systemic tonic which has definite and last- 
 ing benefit. 
 
 If you have access to a gymnasium and will take 
 a half-hour daily for such a routine of exercises, 
 you may overcome the effects of improper diet, and 
 prevent the deterioration of your heart and arte- 
 ries with a fair degree of certainty. 
 
 But unfortunately our modern civilization has
 
 Adding Years to Your Life 265 
 
 not returned to that high standard of the Greeks 
 and Romans in which the gymnasium, with all its 
 facilities for healthful exercise, formed as invari- 
 able a part of the city development as the market 
 place or the dwelling house itself. We shall be 
 forced back to some such standard by and by. The 
 time will come when every large office building and 
 apartment house will have its gymnasium on the 
 roof, to serve as the road to health for young and 
 old of both sexes. But in the meantime, accepting 
 conditions as they are, it is true that a large pro- 
 portion of people have no opportunity to visit a 
 gymnasium and must secure exercise in their own 
 homes or not at all. 
 
 Fortunately it is possible to secure all the exer- 
 cise that health requires without leaving one's own 
 bedroom, and without the use of any parapher- 
 nalia whatever. 
 
 All that is necessary is to select a few intelli- 
 gently devised exercises and to follow them up 
 persistently for fifteen or twenty minutes every 
 morning on first rising. If you will put yourself 
 through a routine of ten or a dozen simple move- 
 ments, aimed to bring into action the muscles 
 which your ordinary occupation leaves undevel- 
 oped, you may secure many of the direct physical 
 benefits of out-of-door games or gymnasium exer- 
 cises without further encroachment on your time 
 or business activities. 
 
 The muscles in question, in the case of ninety- 
 nine persons in a hundred of sedentary habits, are 
 those of the abdominal wall.
 
 266 Adding Years to Your Life 
 
 As you sit at your desk these muscles are re- 
 laxed, and they are brought but slightly into action 
 by 'ordinary walking or by even a fairly vigorous 
 action of the arms. So the muscles that should 
 give strong support to the abdominal wall become 
 a mere film of relaxed and ineffective tissues, 
 padded with useless layers of fat. The all-impor- 
 tant abdominal viscera not only lack normal sup- 
 port, but they are encroached upon and crowded 
 out of place by masses of adipose tissue that sub- 
 serve no useful function. 
 
 The person of distended waist line suffers from 
 shortness of breath, not necessarily because his 
 lungs or heart are affected, but because the adi- 
 pose tissue crowds the liver and other viscera 
 into the thorax, thus restricting the breathing 
 space. But the deposit of excessive quantities of 
 fat is in itself evidence of defective circulation of 
 the blood; and unless the condition is corrected, 
 there is a tendency to weaken the heart, further 
 interfering with the circulation and facilitating 
 thus the degenerative changes which lead to ar- 
 terio-scelerosis with its all too familiar attendant 
 evils. 
 
 But no one need suffer from such degenerated 
 abdominal muscles, or from such accumulation of 
 fat in the region of the waist, if he has the intelli- 
 gence and the strength of mind to follow a sys- 
 tematic line of exercises aimed to keep the abdomi- 
 nal wall in a state of healthful efficiency; assum- 
 ing always that at the same time he will practice 
 reasonable self-restraint in eating.
 
 Adding Years to Your Life 267 
 
 Treating the Abdominal Muscles 
 
 Anyone can devise exercises that will bring the 
 abdominal muscles into action, but unless you have 
 a definite programme you are likely to exercise in 
 so desultory and haphazard a manner as to fail to 
 get the best results. 
 
 It is worth while, then, to outline a definite 
 series of exercises, aimed at all-round development 
 of the abdominal muscles, which may be performed 
 in your own bedroom, and which will bring into 
 action the entire series of neglected muscles, cause 
 the absorption of adipose tissue, and give a health- 
 ful stimulus to heart, lungs, and abdominal vis- 
 cera. Try these for a few mornings, just as an ex- 
 periment. 
 
 Position A. Lie flat on the back, on bed or car- 
 pet, with hands over your head. 
 Exercise 1. Body rigid, knees stiff. Eaise 
 right leg as far as possible, exhaling, knee 
 still rigid ; left leg also rigid, heel press- 
 ing down. Lower right leg till heel almost 
 touches. Repeat several times. 
 Exercise 2. Same as exercise 1, using left 
 
 leg instead of right. 
 Exercise 3. Same motion, using both legs, 
 
 knees still rigid, and feet together. 
 Exercise 4. Eaise and lower legs alter- 
 nately, bending the knees, and bringing 
 thighs full against the chest, and then ex- 
 tending as if trying to run through the 
 air.
 
 B Adding Years to Your Life 
 
 Position B. Stand erect, feet and knees to- 
 gether; arms extended sidewise on level with 
 shoulders; joints of shoulders, elbows, and 
 knees rigid. 
 
 Exercise 5. Pivot body back and forth, 
 swinging arms in half circle, without 
 moving feet ; thus bringing all the action 
 on the waist-muscles. 
 
 Exercise 6. Start from Position B, bend 
 right and left as far as possible, arms al- 
 ways in line, right ascending as left de- 
 scends, each alternately rising above the 
 head and coming close to the thigh ; face 
 turned to look first at one hand and then 
 at the other. Be sure to maintain rigidity 
 of elbows, shoulders, and legs, so that all 
 the action comes on muscles at the sides 
 of the abdomen. 
 
 Position C. Standing, feet apart, knees bent, 
 hands at sides. 
 
 Exercise 7. Swing arms high above head 
 and as far back as possible, inhaling; 
 swing forward, bending body and reach- 
 ing back between the legs as far as pos- 
 sible, exhaling. Eyes follow hands at all 
 times. The front abdominal muscles and 
 muscles of the back are brought into 
 vigorous action. 
 
 Position D. Stand erect, feet together at the 
 heels, toes at right angles, arms flexed against 
 chest.
 
 Adding Years to Your Life 269 
 
 Exercise 8. Raise hands high above the 
 head, inhaling. Lunge forward with left 
 foot, at right angles to right foot; left 
 leg bent, right leg rigidly straight 
 throughout the exercise. Face and 
 shoulders in direction of left foot, thus 
 bringing strain on abdominal muscles of 
 right side. Stoop forward and touch floor 
 with clinched fists in front of left foot, ex- 
 haling; resume original position of body, 
 inhaling, bringing right arm to chest 
 without altering position of legs and left 
 arm. 
 
 Exercise 9. Same as number 8, but making 
 lunge with right leg. 
 
 Exercise 10. Same position and exercise as 
 8, except that both fists are brought to the 
 floor simultaneously in front of left foot, 
 and both raised to the shoulder (always 
 with body strongly turned so that the face 
 is straight in line with left foot). 
 
 Exercise 11. Same as 10, with legs re- 
 versed. 
 
 Exercise 12. Begins like exercise 10, but as 
 hands are brought to the shoulder after 
 touching the floor, the left leg is brought 
 back into original position D, heel to heel, 
 and the arms then lifted above the head, 
 inhaling. Lunge forward again with left 
 foot, keeping hands still high in air. Then 
 stoop, exhaling, and touching fists to floor 
 in front of left foot as before.
 
 270 Adding Years to Your Life 
 
 Exercise 13. Same as 12, but lunging with 
 
 right foot instead of left. 
 
 Position E. Stand erect, feet together, knees 
 rigid. 
 
 Exercise 14. Bend forward, without bend- 
 ing the knees, and touch toes; resume 
 erect position. 
 
 Exercise 15. Erect in Position E. Bend 
 forward till your hands touch the floor; 
 walk forward on hands, without moving 
 feet, until body is fully extended, quad- 
 ruped fashion, on hands and toes; legs 
 and body rigid. Lower body till the chest 
 (but not the abdomen) almost touches 
 the floor; raise by power of the arms; 
 hold the arms rigid, hands on floor, and 
 walk forward till feet come between the 
 hands; then raise to standing position. 
 Face about and repeat. This exercise 
 puts a strain on the abdominal muscles 
 that will surprise you when you first test 
 it. 
 
 Of course each of these exercises should be re- 
 peated several times ; the exact number depending 
 altogether on your physical condition. You may 
 begin with two or three repetitions, and go on 
 adding one or two daily till you repeat each exer- 
 cise fifteen or twenty times. To go through the 
 entire series, repeating each exercise twenty 
 times, requires less than fifteen minutes; and if 
 you will persevere you will come presently, as
 
 Adding Years to Your Life 271 
 
 your muscles gain tone, to find actual pleasure in 
 the work. 
 
 Trading Hours for Years 
 
 Unless you have a definite programme you are 
 likely to exercise in so desultory and haphazard a 
 manner as to fail to get the best results. It is es- 
 sential to outline a definite series of exercises and 
 follow them up systematically. The series just 
 suggested, aimed at all-round development of the 
 abdominal muscles, is practised and recommended 
 by George Bothner, whose wonderful symmetry of 
 development attests the excellence of his methods 
 of training. 
 
 Such a series of home exercises, combined with a 
 rational dietary, will do wonders toward keeping 
 you in health. 
 
 If you will persevere, I repeat, you will come, 
 as your muscles gain tone, to find actual pleasure 
 in the work. But the great difficulty is to get a 
 really good start. If your system has been allowed 
 to get very greatly out of repair, you may not have 
 the will power to carry out a really effective course 
 of gymnastics at home. You will need the stimulus 
 of gymnasium associates, and the dominating in- 
 fluence of a trainer. 
 
 If you are corpulent, it will stimulate arid en- 
 courage you to see men reduced, by a simple sys- 
 tem of gymnastics and gymnasium games regu- 
 larly carried out, from say 240 pounds in weight to 
 a normal weight of 160. 
 
 When you see that such a transformation is not
 
 272 Adding Years to Your Life 
 
 only possible but a moral certainty under proper 
 training, you will be encouraged to go ahead with 
 vigor on the same road to health. 
 
 To get such results, however, it is necessary 
 to exercise with such vigor as to cause profuse 
 perspiration, and to induce a measure of fatigue. 
 And the exercises should be conducted under 
 judicious guidance, partly to insure their 
 adequacy, partly to guard against excess. 
 
 The regeneration effected by even a brief period 
 of rational training is sometimes almost magical. 
 
 As a typical instance, let me cite the case of a 
 man who had sojourned three weeks at Brown's 
 physical culture institution (Pine Hill Farm), at 
 Garrison on the Hudson, near New York. He 
 came to the institution corpulent and flabby of 
 muscle, and suffering from " nervous insomnia 
 and nervous indigestion "; when he went away he 
 was thirty pounds lighter, his indigestion had dis- 
 appeared, and, at home, he reported himself able 
 to sleep early and late, oblivious to the sound of 
 " poker parties and piano players in the neigh- 
 boring apartments," and of trolley cars and early 
 morning trucks. 
 
 In a letter written sometime later he says : 
 
 " I am living for the first time in several years. 
 I am able to do more and better work with less 
 strain that in many years. I wish that many busi- 
 ness men whom I know, and the thousands whom I 
 do not know, who let themselves get out of con- 
 dition and who become physically unfit, and more 
 or less affected with neurasthenia, on account of
 
 Adding Years to Your Life 273 
 
 overwork, lack of exercise, and too much eating 
 and drinking, could possibly realize how good it 
 feels to be alive and in first-class condition. I am 
 certain that if they did they would let their busi- 
 ness wait and ' beat it ' for a place where they can 
 get themselves in shape. From my own experi- 
 ence I feel confident that there is no investment in 
 the world that would be so beneficial or worth so 
 much." 
 
 Such an admonition, born of experience, de- 
 serves your careful consideration. 
 
 You are too busy to follow such advice you say. 
 The excuse is a common one. But the time will 
 come when you will cease to indulge that particular 
 sophistry. As you feel your powers failing, you 
 will realize that your work is not fully accom- 
 plished ; that it is good to go on a few years more 
 in this wonderful world. Then you will seek ad- 
 vice about means to prolong your life. You will 
 wonder if exercise would not be " good for you." 
 
 But if you delay too long you may then be 
 answered as was an American millionaire well- 
 known in the world of high finance, who at the age 
 of about sixty sought a medical specialist to ask 
 the same question. After examining him the spec- 
 ialist said something like this : 
 
 11 You say, Mr. X., that someone has advised 
 you to exercise. That would have been admirable 
 advice ten or twenty years ago. But you have lived 
 so long without exercise, have permitted your tis- 
 sues to get into such a state of disrepair and de- 
 generation, that is is now too late to hope to re-
 
 274 Adding Years to Your Life 
 
 store them to activity. You can only conserve the 
 small measure of physical strength that you retain. 
 Do not exercise. Take a taxi even if you have to 
 go only a few blocks. Save all your strength and 
 keep the machine going at low speed as long as 
 you can." 
 
 To a friend the doctor said afterward that if Mr. 
 X. had begun to exercise at the right age and had 
 taken proper care of his originally good con- 
 stitution, he might very well have hoped to live to 
 be eighty, instead of dying, as he did, at sixty-five. 
 Half an hour a day of the right sort of exercise at 
 the right time would probably have insured him an 
 additional ten or twenty years of life ; but all his 
 millions could not restore the lost opportunity or 
 purchase for the financier an added hour. 
 
 And this case is absolutely typical. Such de- 
 generation of the tissues as that which took the 
 financier prematurely from the scene of his labors 
 causes probably a majority of all deaths of those 
 who live beyond forty. After middle life we have 
 fought off the virulent microbes, our systems are 
 largely immune to them; and the bodily machine 
 wears out, like any other machine, more or less 
 rapidly, according to the care that is taken of it. 
 
 Even pneumonia, that arch-enemy of the aged, 
 is not primarily a germ disease. But for the low- 
 ered vitality of the body, due to sluggish function- 
 ing of the tissues in general and slackening heart 
 action, the microbes, even if lodged in the lungs, 
 would not be able to develop there. 
 
 The great difficulty is that most people cannot be
 
 Adding Years to Your Life 275 
 
 induced to shut the barn door until after the horse 
 is stolen. If this was true of a man of business 
 acumen and foresight, like the financier whose 
 case was just cited, what can be expected of the 
 ordinary mortal? At any rate, if you have read 
 these pages, you are forewarned and if you elect to 
 live a short and inactive life rather than to make 
 bid for a long and active one, you at least make 
 the choice knowingly.
 
 INDEX 
 
 Adding Years to Your Life, 
 
 Chapter IX, 245. 
 Age, the teat of, 245. 
 Alcohol, a depressant to be 
 
 avoided, 64; 
 
 its effect on the brain, 100 ; 
 how it mars the brain, 111. 
 Anaphylaxis, protein, as a 
 
 cause of disease, 250. 
 Ancestors, their great number, 
 
 185; 
 
 and marriage partners, 188; 
 should be studied in the in- 
 terests of posterity, 210. 
 Antitoxins, how prepared and 
 
 how they operate, 56. 
 Aphasia, due to brain injury, 
 
 122. 
 Are Your Nerves in Tune? 
 
 Chapter V, 117. 
 Assimilation, how controlled 
 
 by the sympathetic system, 
 
 124. 
 Asylums, for the insane, now 
 
 commonly called hospitals, 
 
 102. 
 
 Bacillus of long life, its alleged 
 
 action, 17. 
 
 Bacteria, grow by billions on 
 mucous surfaces, 32; 
 
 hostile, how preventive medi- 
 cine is grappling with 
 them, 34; 
 
 cause the great majority of 
 all deaths, 43; 
 
 their classification and mi- 
 nute size, 44; 
 
 how the body is guarded 
 against them, 48; 
 
 the streptococcus one of 
 man's deadliest enemies, 
 48; 
 
 Bacteria, their rapid multipli- 
 cation, 52; 
 some rules for evading them, 
 
 60; 
 
 number permissible in whole- 
 some milk, 68. 
 
 Balliet, Dean Thomas M., heads 
 a committee to report on 
 teaching of sex hygiene, 
 236. 
 
 Barker, Dr. Lewellys F., out- 
 lines objects of the Na- 
 tional Committee for Men- 
 tal Hygiene, 94; 
 comments on the permanent 
 ill-effects of faulty feeding 
 of infants, 219. 
 
 Bath, the, as a therapeutic 
 measure, 63. 
 
 Battle of the Microbes, The, 
 Chapter II, 40. 
 
 Bedbug, the ubiquitous, as a 
 
 carrier of disease, 89; 
 may be destroyed by fumigat- 
 ing the house, 92. 
 
 Beers, Mr. Clifford W., his 
 crusade for the prevention 
 of insanity, 95. 
 
 Behring, Dr. Emil von, de- 
 velops the diphtheria anti- 
 toxin, 57. 
 
 Biffin, Professor R. F., de- 
 velops new races of wheat, 
 205. 
 
 Binet tests, show high percent- 
 age of children below the 
 normal standard, 190. 
 
 Binet-Simon tests of the age of 
 children explained, 224. 
 
 Bird, the, has double vision, 
 161. 
 
 Bishop, Dr. L. F., his studies of 
 food poisons, 250. 
 
 277
 
 2 7 8 
 
 Index 
 
 "Black Death," a name given 
 to the plague in the Middle 
 Ages, 73. 
 
 Blood corpuscles, white, how 
 they protect the body by 
 attacking bacteria, 49; 
 
 named phagocytes, or cell- 
 eaters, by Professor Metch- 
 nikoff, 50; 
 
 details of their combat with 
 
 the disease germs, 54. 
 Blood poisoning, due to mi- 
 
 crobic infection, 47. 
 Blood pressure, what it shows, 
 
 257. 
 Blood-stream, the battle in the, 
 
 50. 
 
 Body, the human, likened to a 
 city, 25; 
 
 as a fortified castle, 48. 
 Brain, why it is so often an 
 inefficient organ of mind, 
 99; 
 
 the mind depends absolutely 
 upon it, 109; 
 
 abnormalities that are in- 
 curable when developed 
 may be preventable, 110; 
 
 how marred by alcohol, 111; 
 
 how marred by syphilis, 114; 
 
 as centre of the nervous sys- 
 tem, 120; 
 
 the brain mechanism, 121; 
 
 how it is imposed upon, 132 ; 
 
 disturbed by mal-nutrition, 
 overwork, worry, and 
 bursts of emotion, 135; 
 
 as a phonograph, 145; 
 
 its records are permanent, 
 148; 
 
 its training cannot be begun 
 too early, 151; 
 
 of the child, indelibly marked 
 by early experiences, 221. 
 Brown, Dr. J. S., leads a cru- 
 sade for pure milk in Mont- 
 clair, 68. 
 
 Bulgaria, peasants of, their 
 longevity ascribed by 
 Metchnikoff to their sour- 
 milk diet, 16. 
 
 Burbnnk, Luther, independent 
 discoveries in heredity, 
 204. 
 
 Burrows, Dr. Montrose T., his 
 experiments with Dr. Car- 
 rel in growing tissues out- 
 side the body, 30. 
 
 Can You See Straight? Chapter 
 VI, 153. 
 
 Carrel, Dr. Alexis, his experi- 
 ments with Dr. Burrows in 
 growing tissues outside the 
 body, 30; 
 
 studies the effect of different 
 foodstuffs on cell growth, 
 36. 
 
 Castle, Professor William E., 
 his experiments with 
 guinea pigs, 188. 
 
 Cells, living, how they build up 
 
 the organism, 24; 
 Dr. Carrel studies their needs, 
 
 36; 
 
 aided by the sympathetic 
 nervous system, 128. 
 
 Children, do you choose them? 
 Chapter VII, 181. 
 
 Children, "exceptional," their 
 large number as deter- 
 mined by the Binet tests, 
 190. 
 
 Children, give them a chance, 
 Chapter VIII, 213. 
 
 Children, timidity of, some- 
 times due to organic dis- 
 ease, 222; 
 actual age versus mental 
 
 age, 223; 
 
 the value of right hygiene in 
 giving health and normal- 
 ity, 227; 
 moral training of, 232. 
 
 Chowning, Dr., in association 
 with Dr. Wilson, suggests 
 that the wood-tick trans- 
 mits Rocky Mountain spot- 
 ted fever, 86. 
 
 City, the modern, has lower 
 death-rate than the coun- 
 try, 28.
 
 Index 
 
 279 
 
 Clark, Dr. Ernest, urges the 
 safeguarding of the child's 
 eyes, 175; 
 
 regards insomnia as a com- 
 mon symptom of eye-strain, 
 177. 
 
 Consumption, causes ten per 
 cent of all deaths, 40. 
 
 Cousins, the marriage of, 195; 
 the marriage of, instances of 
 harmful effects through 
 heredity, 197; 
 
 the marriage of, not neces- 
 s a r i 1 y disadvantageous, 
 198. 
 
 Davenport, Professor C. B., on 
 marriage of persons having 
 susceptibility to tubercu- 
 losis, 192; 
 
 his collection of human pedi- 
 grees, 205. 
 
 Deaf-mutism, in relation to 
 heredity, 196. 
 
 Degenerative diseases on the 
 increase, 248. 
 
 Diet, its great importance in 
 
 prolonging life, 38; 
 a rational, 259. 
 
 Digestion and assimilation, how 
 controlled by sympathetic 
 system, 124. 
 
 Do You Choose Your Children? 
 Chapter VII, 181. 
 
 Eating to live, 259. 
 
 Ehrlich, Professor Paul, his 
 new remedy for syphilis, 
 35; 
 
 attempts to perfect a remedy 
 for sleeping sickness, 88. 
 
 Emerson, Mr. Harrington, illus- 
 trates the need of psycho- 
 logical tests to determine 
 business fitness, 138. 
 
 Environment vs. heredity, 182. 
 
 Epilepsy, due to lack of cerebal 
 control, 123. 
 
 Eugenics. See Chapter VII, Do 
 You Choose Your Children? 
 181. 
 
 Eugenics Record Office, at Cold 
 Spring Harbor, its work in 
 tracing genealogical rec- 
 ords, 211. 
 
 Evolution, determined by mat- 
 ing selections, 186. 
 Exercise, its value in promot- 
 ing longevity, 38; 
 the sovereign remedy, 262. 
 Exercises, a system of, for home 
 
 use, 267. 
 Eye, the, compared to a camera, 
 
 155; 
 defects that we nearly all 
 
 have, 166; 
 
 secondary effects of eye- 
 strain, 166; 
 
 defects, very heritable, 194. 
 Eyes, primitive, how they func- 
 tionate, 157 ; 
 of lower animals, 159; 
 out of focus, 164; 
 of crustaceans, are replaced 
 
 if destroyed, 165; 
 how tested, 167; 
 how to take care of, 169; 
 guarding the eyes of the 
 
 child, 174; 
 
 small defects are most dan- 
 gerous, 176; 
 
 of the child, should be ex- 
 amined by oculist from 
 time to time, 180. 
 Eye-strain, may cause various 
 
 maladies, 153; 
 how influenced by occupation, 
 
 171; 
 due to defective light and 
 
 desks in school, 177. 
 Eye surgery, some remarkable 
 operations, 153. 
 
 Finlay, Dr. Charles J., early 
 advocated the theory that 
 yellow fever is transmitted 
 l>y mosquitoes, 79. 
 
 Fisher, Professor Irving, esti- 
 mates that six hundred 
 and thirty thousand pre- 
 ventable deaths occur in 
 America each year, 42.
 
 280 
 
 Index 
 
 Flea, the, a carrier of the 
 
 plague, 72. 
 
 Fly, the house, as a carrier of 
 disease, 71; 
 
 more destructive than bullets 
 in the Cuban War, 81 ; 
 
 re-christened the " typhoid 
 fly" by Dr. L. O. Howard, 
 81; 
 
 how it transports disease 
 germs, 82; 
 
 its extreme fecundity, 83; 
 
 protection against, by hy- 
 gienic measures, 83. 
 Foods, their chemical composi- 
 tion, 19; 
 
 a scientific study of their 
 
 qualities made possible by 
 
 D-. Carrel's experiments, 
 
 37. 
 
 Fuel, for the bodily engine, 254. 
 
 Give Your Children a Chance, 
 
 Chapter VIII, 213. 
 Glycobacterium, the "bacillus 
 
 of long life," discovered 
 
 at the Pasteur Institute, 
 
 17. 
 Goddard, Dr. H. H., his study 
 
 of defectives, 203; 
 applies Binet-Simon tests to 
 
 school children in New 
 
 York, 225. 
 
 Gould, Dr. George W., as- 
 cribes many infirmities to 
 
 eye-strain, 172. 
 "Great Mortality," a name 
 
 given to the plague in the 
 
 Middle Ages, 73. 
 Growing old, an unexplained 
 
 mystery, 15. 
 Growing tissues outside the 
 
 body, 29. 
 Guests that shorten our lives, 
 
 32. 
 Guinea pig, used to illustrate 
 
 laws of heredity, 187; 
 further illustrations of the 
 
 laws of heredity, 200. 
 Gymnasium, as an aid to long 
 
 life, 264. 
 
 Hall, President G. Stanley, de- 
 clares that there is a new 
 interest in children in our 
 generation, 220. 
 
 Harrington, Dr. Thomas F., em- 
 phasizes the value of moth- 
 er's milk in feeding the 
 infant, 217. 
 
 Health, some rules for its main- 
 tenance, 60. 
 
 Heart, fragments of its tissue 
 may continue to beat for 
 some months after removal, 
 31. 
 
 Heart disease, a heritable mal- 
 ady, 193. 
 
 Heredity, the new knowledge of, 
 
 184; 
 
 the same laws apply to ani- 
 mal and man, 200. 
 
 Hewitt, Mr. Peter Cooper, his 
 quartz lamp destroys bac- 
 teria, 65. 
 
 Howard, Dr. L. O., gives the 
 house-fly the name " ty- 
 phoid fly," 81. 
 
 Individual, the, and the race, 
 198. 
 
 Indols, their presence in the in- 
 testinal tract believed to be 
 deleterious, 18. 
 
 Infants, handicapped by im- 
 proper feeding, 217. 
 
 Inheritance, from remote ances- 
 tors, 182; 189; 
 of eye defects, 194; 
 of good health, 202. 
 
 Insane, the, about 200,000 in 
 institutions in the United 
 States, 101.; 
 cost of maintenance in the 
 
 United States, 102; 
 recent reforms in their treat- 
 ment, 103. 
 
 Insects, how they transmit dis- 
 ease germs, 53. 
 
 Insomnia, often due to eye- 
 strain, 177. 
 
 Introspection, as a means of 
 self-betterment, 145.
 
 Index 
 
 281 
 
 Is Your Brain All Right? Chap- 
 ter IV, 93. 
 
 James, Professor William, his 
 characterization of Mr. 
 Beers' book, 95. 
 
 Jenner, Dr. Edward, controlled 
 smallpox by vaccination, 
 40. 
 
 Jennings, Professor H. S., 
 shows that protozoa may 
 be kept in health for thou- 
 sands of generations, 23; 
 believes that artificial condi- 
 tions in the body make in- 
 definite existence impos- 
 sible, 26. 
 
 Jordan, Dr. E. O., estimates the 
 rate of development of bac- 
 teria, 52. 
 
 Kilborne, Dr., in association 
 with Dr. Smith, proved 
 that the tick transmits 
 Texas fever in cattle, 86. 
 
 King, Dr. A. F. A., first sug- 
 gested that the mosquito 
 may transmit malaria, 78. 
 
 Laboratory, the psychological, 
 how it may aid the work- 
 shop, 141. 
 
 Lazear, Dr., with Drs. Reed, 
 Carroll, and Agramonte, 
 demonstrated that a mos- 
 quito transmits yellow 
 fever, 80. 
 
 Lens, the crystalline, its func- 
 tion in the eye, 156. 
 
 Light, the best for reading, 171. 
 
 Listerism, how it has changed 
 surgery, 55. 
 
 McClintic, Dr. T. B., a martyr 
 in the cause of science, 86. 
 
 Machine, the animal, 252. 
 
 Malaria, due to a germ called a 
 
 Plasmodium 77; 
 transmitted by mosquitoes, 
 
 Marriage partners, the all-im- 
 
 portance of a right selec- 
 tion, 189; 
 Marriage salvation through 
 
 wise selection of, 206. 
 Maupas, Professor, his experi- 
 ments with protozoa, 22. 
 Meltzer, Dr. S. J., kills dogs 
 
 and restores them to life 
 
 by artificial respiration, 31. 
 
 Memory, its usual defects, 98; 
 
 how explained in terms of 
 
 brain activity, 122. 
 Mendel, Gregor, his studies of 
 
 heredity rediscovered by 
 
 Professor de Vries, 204. 
 Mendelian heredity, 204; 
 
 applied to the human subject, 
 
 202, 207. 
 Mental Hygiene Conference and 
 
 Exhibit, in New York City, 
 
 93. 
 Mental hygiene, its meaning 
 
 and value, 108. 
 Mentally wavering, first aid to 
 
 the, 105. 
 Messengers of Death and How 
 
 to Outwit Them, Chapter 
 
 III, 71. 
 Metchnikoff, Professor Elie, 
 
 proves that white blood 
 
 corpuscles destroy bacteria, 
 
 16; 
 gives the name phagocytes to 
 
 the white blood corpuscles, 
 
 50. 
 Microbes, The Battle of the, 
 
 Chapter II, 40. 
 Microbes, fifty different species 
 
 or varieties may exist in 
 
 the mouth, 44; 
 seemingly friendly ones some- 
 times harmful, 46; 
 destroyed by sunlight, 64. 
 Milk, alleged value of sour in 
 
 prolonging life, 17; 
 purified by quartz lamp, 65; 
 bacteria in, 68; 
 its rapid contamination by 
 
 bacteria, 69; 
 pasteurization of, increases 
 
 its purity, 70.
 
 282 
 
 Index 
 
 Mind, the, its dependence on 
 the brain, 109. 
 
 Minot, Professor Sedgwick, be- 
 lieves that multi-cellular 
 organisms cannot live in- 
 definitely, 27. 
 
 Mortality, is it the price of 
 cellular differentiation? 
 26; 
 
 of infants, amounts to forty 
 thousand daily, 42. 
 
 Mortality rate, infants', reduced 
 fifty per cent by pasteur- 
 ized milk, 70. 
 
 Mosquito, the yellow fever, 79. 
 
 Mosquitoes and malaria, 76. 
 
 Mlinsterberg, Professor Hugo, 
 would apply laboratory 
 methods to determine fit- 
 ness for various callings, 
 139. 
 
 Muscles, how controlled by the 
 brain, 123. 
 
 National Committee for Mental 
 Hygiene, its aims and ob- 
 jects, 94. 
 
 Nature versus nurture, 227. 
 
 Negro population, the possible 
 menace from, 209. 
 
 Nerves, Are Your Nerves in 
 Tune? Chapter V, 117. 
 
 Nervous system, the . sympa- 
 thetic, its functions, 124. 
 
 Nervous systems, the two, and 
 
 their functions, 117; 
 likened to a telephone sys- 
 tem, 118. 
 
 Nott, Dr., early suggested that 
 the mosquito may transmit 
 yellow fever, 79. 
 
 Nurture versus nature, 227. 
 
 Nuttall, Dr. G. H. F., makes 
 extensive study of ticks as 
 germ carriers, 87. 
 
 Old Age, The Duel with, Chap- 
 ter I, 15. 
 
 Old age, examples of men who 
 have evaded its effects by 
 right living, 39. 
 
 Ophthalmoscope, for testing the 
 eye, invented by Helmholtz, 
 167. 
 
 " Opsonin," discovered by Sir 
 Almroth Wright, 58. 
 
 Organism, of man, like that of 
 all other animals built ex- 
 clusively of cells, 23. 
 
 Panama Canal Zone, made sa- 
 lubrious by Colonel Gor- 
 gas, 80. 
 
 Paracelsus, medieval alchem- 
 ist, believed that all foods 
 contained elements of poi- 
 son, 18. 
 
 Paton, Dr. Stewart, prepared 
 Mental Hygiene Exhibit, 
 
 no 
 
 Patton, Dr., shows that " kala 
 azar" may be transmitted 
 by the bedbug, 89. 
 
 Personality, building a new, 
 150. 
 
 Peterson, Dr. Frederick, testa 
 the unconscious and sub- 
 conscious mentality, 149. 
 
 Phenols, their presence in the 
 intestinal tract believed to 
 be deleterious, 18. 
 
 Phonograph, the brain com- 
 pared with, 145. 
 
 Physical culture, regeneration 
 through, 272. 
 
 Plague, the, transmitted by the 
 
 flea, 72; 
 
 at our doors, 72; 
 its dissemination in recent 
 
 years, 74; 
 
 may be transmitted by the 
 bedbug as well as by the 
 flea, 89. 
 
 Playground versus schoolroom, 
 229. 
 
 Pneumonia, how to avoid it, 62. 
 
 Poisoning, due to the retention 
 of organic compounds, be- 
 lieved by Metchnikoff to 
 cause senility, 20. 
 
 Proteid foods, may cause brit- 
 tle arteries, 246.
 
 Index 
 
 283 
 
 Protein, the amount required 
 daily, 259. 
 
 Protein poisoning, how it may 
 affect the organism, 256. 
 
 Protozoan, its alleged immor- 
 tality, 20; 
 method of reproduction, 21. 
 
 Psychiatric clinics, at Johns- 
 Hopkins and elsewhere, 
 105. 
 
 Psychology, how it may aid in 
 selecting a business, 139. 
 
 Rat, the, transmits the plague, 
 74. 
 
 Refraction, errors of, what tfcey 
 mean and what they do, 
 155. 
 
 Rickets, Dr. H. T., demonstrates 
 that the wood-tick trans- 
 mits Rocky Mountain spot- 
 ted fever, 86. 
 
 Rocky Mountain fever, trans- 
 mitted by the wood-tick, 86. 
 
 Ross, Dr. Ronald, discovered 
 that the mosquito trans- 
 mits malaria, 78. 
 
 Salmon, Dr. Thomas W., direct- 
 or of special studies of the 
 National Committee for 
 Mental Hygiene, 97; 
 asserts that the insane are 
 still inadequately cared for 
 in some American com- 
 munities, 104. 
 
 School Hygiene, meeting of the 
 Fourth International Con- 
 gress of, 214. 
 
 Selection, salvation through 
 wise selection of marriage 
 partners, 206. 
 
 Sex education, the need of, 234 ; 
 must begin early, 238. 
 
 Single-celled organisms, be- 
 lieved not to die a normal 
 death, 20. 
 
 Sleep, necessary to restore ex- 
 hausted brain, 135. 
 
 Sleeping sickness, transmitted 
 by the tsetse fly, 87. 
 
 Smith, Dr. Theobald, in asso- 
 ciation with Dr. Kilborne, 
 proved that the tick trans- 
 mits Texas fever in cattle, 
 86. 
 
 Sunlight, its value in destroy- 
 ing microbes, 64. 
 
 Surgery, antiseptic and aseptic, 
 what it really implies, 55. 
 
 Sympathetic nervous system, 
 its control of the involun- 
 tary functions, 124; 
 its function likened to that 
 of the commissary depart- 
 ment of an army, 129. 
 
 Syphilis, and brain decay, 114. 
 
 Telephone girls, suffer from eye- 
 strain, 173. 
 
 Temperature, uniform, of the 
 body, how it is maintained, 
 253. 
 
 Tendencies, hereditary, the con- 
 flict of, 187. 
 
 Texas fever, a destructive cattle 
 malady, due to a protozoal 
 germ transmitted by the 
 tick, 85. 
 
 Ticks, and other creepers, how 
 they transmit disease, 84. 
 
 Tick, the wood-, transmits 
 Rocky Mountain spotted 
 fever, 86. 
 
 Tissues, living, grown oulside 
 the body, 29. 
 
 Tree, your family, 191. 
 
 Tuberculosis, will some day be 
 held in check by an immu- 
 nizing virus, 41 ; 
 two persons both susceptible 
 to, should not marry, 192. 
 
 Vaccine treatment, its wide 
 
 scope, 58. 
 Vaughan, Professor Victor C., 
 
 his studies of food poisons, 
 
 250. 
 Verjbitski, Dr. D. T., shows 
 
 that bubonic plague may 
 
 be transmitted by bedbug 
 
 and flea, 89.
 
 Index 
 
 Vision, its importance in build- 
 ing up the mind, 158; 
 
 binocular, confined to the 
 highest animals and man, 
 161; 
 
 double, what it accomplishes, 
 162. 
 
 Wassermann, Professor, A. von, 
 his attempt to develop a 
 cancer cure, 35. 
 
 Water, how to insure its pu- 
 rity, 67. 
 
 Weismann, Professor August, 
 his theory that single-celled 
 organisms live indefinitely, 
 22. 
 
 Welch, Dr. William, instru- 
 mental in securing endow- 
 ment for a psychiatric 
 clinic, 105. 
 
 Wheeler, Dr. John M., his oper- 
 ations on the eye, 154. 
 
 Wilson, Dr., in association with 
 Dr. Chowning, suggests 
 that the wood-tick trans- 
 mits Rocky Mountain spot- 
 ted fever, 86. 
 
 Woodhead, Dr. G. Sims, de- 
 scribes the effect of alcohol 
 on the brain, 112. 
 
 Wounds, even minor ones 
 should be treated with re- 
 spect, 61. 
 
 Wright, Sir Almroth, discovers 
 " opsinin " and its function 
 in aiding the white cor- 
 puscles, 58; 
 
 his wide application of the 
 vaccine treatment, 59. 
 
 Yellow fever, the demonstration 
 that it is transmitted by a 
 mosquito of the genus 
 Stegomyia made by U. S. 
 Army surgeons, 80.
 
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