GULICR HYGIENE SERIES 
 
 THE BODY AT 
 WORK 
 
 BY FRANCES GULICK JEWETT 
 
1909 
 
 
 LIBRARY 
 
 OF THE 
 
 UNIVERSITY OF CALIFORNIA. 
 
 BIOLOGY 
 
 LIBRARY 
 
 G 
 
 Class 
 
THE GULICK HYGIENE SERIES 
 
 BY 
 
 LUTHER HALSEY GULICK, M.D. 
 
THE GULICK HYGIENE SERIES 
 
 BOOK FOUR 
 
 THE BODY AT WORK 
 
 BY 
 
 FRANCES GULICK JEWETT 
 
 UNIVERSITY 
 
 Of 
 
 GINN & COMPANY 
 
 BOSTON NEW YORK CHICAGO LONDON 
 
BIOLOGY 
 R 
 6 
 
 ENTERED AT STATIONERS' HALL 
 
 COPYRIGHT, 1909, BY 
 LUTHER H. GULICK 
 
 ALL RIGHTS RESERVED 
 
 99-3 
 
 gtftengum 
 
 GINN & COMPANY PRO- 
 PRIETORS BOSTON U.S.A. 
 
EDITOR'S NOTE 
 
 The primary object which has been sought in the 
 preparation of this series of text-books on physiology 
 and hygiene is the establishment of those hygienic 
 habits which are basal to personal wholesomeness and 
 efficiency. It is recognized that mere knowledge of an 
 intellectual character is ineffective. We all know much 
 better than we do. Only that knowledge is effective 
 which is related to doing, knowledge which we actu- 
 ally put into practice. The effect of knowledge upon 
 action is an important, even if not the ultimate, criterion 
 of its value. It is relatively useless to teach children 
 about the body, unless the teaching is done in such a way 
 as to lead them to desire to form their lives accordingly. 
 
 Habits are established not merely or mainly as the 
 result of intellectual conceptions. Our daily habits are 
 to a large extent a social inheritance from the customs 
 of those among whom we grow up. This is true regard- 
 ing the forms of our speech, the character of our cloth- 
 ing, habits of social intercourse, and the like, and it is 
 not less true in the forming of hygienic habits. 
 
 The main object, then, in this series is to introduce 
 that atmosphere, both of intellectual comprehension and 
 
 V 
 
 182494 
 
\ 
 
 vi THE BODY AT WORK 
 
 social custom, which shall result in the unconscious as 
 well as the conscious development of the individual in 
 these directions. An attempt is made to accomplish this 
 through the different volumes of this series, though the 
 method pursued differs somewhat with each volume. 
 
 (1) During the first three years of school life, in 
 which the instruction is entirely oral, the most impor- 
 tant aspects of personal hygiene are those which are 
 taught not as theoretical lessons but as personal 
 experiences. Cleanliness of hands and face, and of 
 clothing and the room, freshness of the air, tempera- 
 ture, these are taught not so much by formal lessons 
 as by the teacher insisting that the pupils be clean, 
 that their clothing be repaired and in order, that the 
 room be clean, comfortable, well ventilated, etc. These 
 matters should, of course, be called to the attention of 
 the pupils as well as carried out in practice. The per- 
 sonal cleanliness and neatness of dress of the teacher 
 are, of course, predominant factors in this whole matter. 
 
 (2) The volume entitled Good Health was written for 
 the fourth grade. In this a general view is taken of 
 the subject. Scarcely any anatomy and relatively little 
 physiology are given, the main contents of the book 
 consisting of concrete and interesting facts relating to 
 pure air, tobacco, cleanliness, sleeping, eyesight, alcohol, 
 hearing, finger nails, hair, care of the nose and teeth, 
 and eating. 
 
EDITOR'S NOTE vii 
 
 (3) The second volume in the series, Emergencies, ap- 
 proaches the subject of the formation of habits from the 
 standpoint of the emergencies which come to children. 
 Many of the same subjects are treated here that are dis- 
 cussed in the other volumes of the series, but from this 
 special standpoint. The skin is discussed, not from the 
 standpoint of general health or cleanliness, but from that 
 of blisters and burns. The habits that it is desirable 
 for children to form with reference to conduct during 
 emergencies form the subject-matter of the year. It in- 
 cludes many of the topics that are ordinarily discussed 
 under the subject of physiology and hygiene, but they 
 are presented from this special point of view, a point 
 of view that is new to the child. 
 
 (4) The volume Town and City, which is prepared for 
 the sixth year of school life, presents the subject of 
 hygiene from the standpoint of the community, and 
 habits of action which have a social bearing are dis- 
 cussed, the results of overcrowding, clean streets, gar- 
 bage, ashes and refuse, parks, playground, public baths, 
 water supply, preventable diseases, food inspection, epi- 
 demics, vaccination, tuberculosis, city health and alcohol, 
 microbes and disease. These are all topics in which in- 
 dividual action is involved. In all of them the relation 
 and special emphasis are with reference to the state. 
 The book is thus made an agency for the formation of 
 habits having a community bearing. 
 
viii THE BODY AT WORK 
 
 (5) The fourth volume, The Body at Work, which is 
 intended for the seventh grade, covers somewhat in 
 detail the subjects ordinarily covered in the standard 
 physiologies, but the emphasis is laid on the training of 
 the body for efficiency. Thus much is said concerning 
 the importance of good posture and how to secure it ; 
 how one trains the muscles of the body that they may 
 be efficient, enduring, and strong; the nature and char- 
 acteristics of useful exercise; how digestion is most 
 efficiently carried on. The whole point of view con- 
 cerns the training of the individual to most efficient 
 bodily conduct. It relates particularly to the large 
 physiological functions of digestion, circulation, nutri- 
 tion, and respiration. 
 
 (6) The closing volume of the series relates directly 
 to the establishment of habits themselves. The title of 
 the book is Control of Body and Mind. In this book is 
 discussed with some detail how habits are formed, not 
 so much as a theory, but as an experience ; how habits 
 are broken, fatigue, the wholesome development of the 
 brain and the spinal cord, the freedom which well- 
 ordered habits give to the person who has them, the 
 nerve endings and their care, etc. The whole purpose 
 of the book is to give the individual that information 
 which is related to the establishment of wholesome 
 habits, particularly wholesome habits which shall be 
 effective in the control of conduct. 
 
EDITOR'S NOTE ix 
 
 Thus, while the direct object of this series concerns 
 itself with conduct, particularly conduct with reference 
 to health and efficiency, it covers all of the ground usu- 
 ally covered by discussions on physiology and hygiene. 
 Because of the different points of view which are brought 
 out during the different years, the range of facts pre- 
 sented is far greater than has ever before been presented 
 
 to children. 
 
 LUTHER HALSEY GULICK 
 

 CONTENTS 
 
 CHAPTER PAGE 
 
 I. BONE AND MUSCLE RECORDS i 
 
 II. DANGER FROM THE SCHOOL DESK 9 
 
 III. MUSCLES CONTRACTING AND STRETCHING 18 
 
 IV. THE MUSCLE ITSELF 24 
 
 V. STIFF SUPPORT FOR GROUPS OF MUSCLES 34 
 
 VI. BONDAGE AND FREEDOM FOR THE FEET 44 
 
 VII. ASSISTANCE FROM JOINTS 51 
 
 VIII. THINGS THAT HINDER STRENGTH AND SPEED .... 58 
 
 IX. THE HEART WHEN IT is AT WORK 67 
 
 X. DISCOVERIES BY A GRECIAN AND AN ENGLISHMAN . . 77 
 
 XI. To THE CAPILLARIES AND BACK 88 
 
 XII. BLOOD INSIDE AND OUTSIDE THE TUBES 96 
 
 XIII. EXCHANGES ALONG THE TUBES 102 
 
 XIV. ALCOHOL AND CIRCULATION "... 109 
 
 XV. As WE GROW BREATHLESS 117 
 
 XVI. WHERE BLOOD CHANGES COLOR 124 
 
 XVII. ADULTERATED ALCOHOL AND PATENT MEDICINE . . . 132 
 
 XVIII. EXPERIMENTS IN EATING 139 
 
 XIX. CATS UNDER THE X-RAY 149 
 
 XX. FROM FOOD TO BLOOD ; OR, PERISTALTIC ACTION AND 
 
 THE VlLLI 157 
 
 xi 
 
xii CONTENTS 
 
 CHAPTER PAGE 
 
 XXI. GLAND LABORATORIES FOR THE AID OF APPETITE AND 
 
 GENERAL HEALTH ............ ^5 
 
 XXII. GLAND LABORATORIES INFLUENCED BY ALCOHOL . 173 
 
 XXIII. HAMPERED BY CLOTHING, OR ABOVE AND BELOW THE 
 
 DIAPHRAGM. ............ jgo 
 
 XXIV. FOOD OR DRINK FOR OKUSHIRI ISLANDERS . ... 191 
 XXV. THAT WHICH DESTROYS, AND HOW MEN SAVE THEM- 
 SELVES ....... T g7 
 
 XXVI. PROTECTED BY THE SKIN ....... 204 
 
 XXVII. WORK, HEAT, AND FUEL ......... 212 
 
 BIBLIOGRAPHICAL LIST 210 
 
 QUESTIONS . ... \ ........ 221 
 
 GLOSSARY . . . . . . . ... . . . 237 
 
 INDEX ^ ....../.. 241 
 
OF THE 
 
 ( UNIVERSITY 
 
 V OF 
 
 Xis 
 
 INTRODUCTION 
 
 In the following pages emphasis is laid on function 
 rather than on structure, on bodily health rather than on 
 the mere mechanical operation of bone, muscle, gland, 
 and tissue. So much of structure is, however, included 
 as is necessary to show that we are personally respon- 
 sible for the kind of service which we receive from the 
 organs of the body rand that we are equally responsible 
 for the habits of bone and muscle which determine the 
 physical representation of ourselves to others. 
 
 Attention is drawn to right and wrong habits of sit- 
 ting, of standing, and of walking; to the relation of the 
 school desk to spinal curvature ; to laws of growth, 
 through the knowledge of which correct habits of pos- 
 ture may be secured ; to the value of physical exercise 
 as an aid to general health ; to the development of mus- 
 cular vigor and to the renewal of tissue through food 
 and exercise. 
 
 By natural transition the work of the muscles leads to 
 a study of the source of their energy,- the blood. Sim- 
 ple tests easily applied, acquaint the reader with the 
 cause of rapid and slow heart beat, with methods of 
 training the heart to increased power, with reasons 
 
xiv THE BODY AT WORK 
 
 why an untrained heart should not be overtaxed, with 
 the work of the lymphatics and the nature of the ex- 
 changes made between lymph and plasma. The insidi- 
 ous effects of alcohol on the heart and on the entire 
 circulatory system is emphasized. 
 
 Certain conditions of breathlessness are discussed, 
 and reasons are given for the statement that a man 
 runs as much with his heart and with his lungs as 
 with his legs. In natural sequence, this explanation 
 involves not merely the structure and the function of 
 the lungs but also a study of the exchange of gases 
 both in the tissues and in the air sacs. 
 
 The notable experiments of Professor Chittenden 
 with United States soldiers in New Haven, and of 
 Dr. Cannon with cats in the Harvard Medical School, 
 necessarily add a touch of picturesque reality to the 
 otherwise prosaic subject of digestion. At the same 
 time these experiments serve to illustrate the action 
 of digestive juices on food, the effects of rapid eating 
 on the nourishment of the body, the movement of the 
 walls of the stomach during digestion, and the effect of 
 fatigue, of unhappiness, of worry, anger, and anxiety on 
 the normal progress of digestion. 
 
 Through this introduction to the subject prominence 
 is given to the change of food from solid to liquid form, 
 and to its absorption by the villi ; also to the food require- 
 ments of the body under differing conditions of age and 
 
INTRODUCTION XV 
 
 activity ; to the value of bulk in the food supply ; to the 
 functions of the liver and of the kidneys, and to the in- 
 fluence of alcohol in undermining their power for work; 
 to the relation of sweat glands to bodily heat, and to the 
 interdependence of work, heat, and fuel in the operations 
 of the body. 
 
 These and other related topics have been brought to 
 the notice of the students of this volume with the hope 
 of imparting such enthusiasm for personal health and 
 such clear notions of how to secure it, that the bodies 
 of growing children may be strengthened as well as 
 straightened, that lives may thereby be lengthened, and 
 that through increased physical well-being the sum of 
 human happiness may itself be increased. 
 
 Not merely is it the purpose of this series to teach 
 scientific facts, but also, and especially, so to arrange 
 and present these facts that from page to page they 
 shall hold the reader's close attention and inspire per- 
 sonal loyalty to the laws of health. To further this pur- 
 pose side headings have intentionally been omitted, so 
 that each chapter may make its first appeal to the reader 
 as a unified whole rather than as a series of disjointed 
 fragments. While the disadvantages of side headings in 
 interrupting th ^continuity of thought have been avoided, 
 all their advantages are secured through the questions at 
 the end of the volume, which, in a better form, answer 
 the same purpose. 
 
xvi THE BODY AT WORK 
 
 In so far as possible, the instruction of this text-book 
 is everywhere reenforced by illustrations. Some of these 
 are from photographs supplied by the author, others 
 are copies of such as are already in wide use, while 
 still others have been secured through the courtesy of 
 the authors and publishers of notable investigations. 
 Special mention should be made of indebtedness to the 
 American Journal of Physiology for illustrations used 
 by Dr. Cannon in his article on "The Movements of the 
 Stomach studied by Means of the Rontgen Rays" (1898), 
 and to Professor Chittenden for photographs of the 
 soldiers with whom he carried on his food experiments. 
 
 Other valuable illustrations have been reproduced 
 from Practical Hygiene by Alice Ravenhill, from The 
 Human Mechanism by Theodore Hough and W. T. 
 Sedgwick, from Alcohol and the Human Body by Sir 
 Victor Horsley and Mary D. Sturge, and from Unser 
 Korper by F. A. Schmidt. To each of these and to 
 many other important works this little book is indebted 
 not merely for illustrations but also for valuable facts 
 which have been used in the preparation of its sub- 
 ject-matter. 
 
 r . (jr. J. 
 
THE BODY AT WORK 
 
 CHAPTER I 
 
 BONE AND MUSCLE RECORDS 
 
 Many cases are on record where a man has tried to 
 hide his face when he thought his photograph was to 
 be taken. He has seemed to understand that the photo- 
 graph might betray him some day and lead to his being 
 arrested again. 
 
 But some of our largest cities have adopted a new 
 and surer way of keeping a reminder of their captured 
 men. They measure each man carefully in different di- 
 rections, height in standing and in sitting, distance 
 from the outstretched finger tip of one hand to the out- 
 stretched finger tip of the other, length and width of 
 head and face and right ear, length of left foot, of left 
 middle finger, and of left forearm. Scars are noticed and 
 recorded ; also the color of the hair and eyes, the shape 
 of the nose, the number of teeth, etc. 
 
 In addition, the photograph is taken. And, queer 
 though it may seem, the photograph is less important 
 than the measurements in identifying a man if he is 
 
THE BODY AT WORK 
 
 ever arrested again and brought to the police station. 
 
 The reason is that our bone measurements do not 
 
 change after we are twenty-two years old. Ever after 
 
 that the size of face and head, 
 the length of arms, of fingers, 
 and of legs are all as they will 
 continue to be until we die. 
 
 This, then, is a sure and 
 sensible way of keeping the 
 record of a man. When a 
 criminal arrives at the police 
 court, no matter how violently 
 he declares that he has never 
 been there before and that 
 this is his first offense, the 
 officers measure him at once 
 and also search their written 
 records. If they find there any 
 set of measurements which is 
 a duplicate of those just taken, 
 all the man's denials are in 
 vain. Those officers know that 
 never yet have two people 
 
 been found who had precisely the same dimensions for 
 
 all the bones which were measured. 
 
 It takes but ten minutes for the officers to get their 
 
 record of a man photograph and all. But it took the 
 
 TAKING THE, LENGTH AND THE 
 WIDTH OF HIS HEAD 
 
 A caliper compass is used 
 
BONE AND MUSCLE RECORDS 
 
 man himself twenty-two years of life to make that body 
 which- is now his physical record of himself. 
 
 As a rule the body of a baby is very perfect ; but even 
 in its cradle and before it can 
 walk a step or speak a word it 
 begins to receive daily training of 
 muscles and bones, of eyes and 
 hands and brain. During these 
 early months also older persons 
 feel great responsibility for the 
 child. 
 
 Notice any nurse or careful 
 mother with the baby in her 
 arms. See her hold a firm hand 
 against the back of the head as 
 she supports the backbone and 
 holds the child up for a look at 
 the world. She knows, as the doc- 
 tor does, that for months there is 
 more cartilage than bone in the 
 supports of that small body, and SEATED T0 BE MEASURED 
 that, while bones are in this con- With his back against the up _ 
 
 dition, they Cannot be trusted tO right scale they measure the 
 . height of his trunk 
 
 do independent work. 
 
 Later, when the baby begins to walk, notice how 
 anxious the same mother is lest the legs of the child 
 be used too long at a time. Her fear is that those bones, 
 
THE BODY AT WORK 
 
 which are even now partly cartilage, may be so trained 
 as to disgrace the body later in life. She may have heard 
 that bowlegs often result from a disease called rickets, 
 but she also fears lest, even without the disease, bowlegs 
 may come from early walking ; and she hopes to make 
 it impossible for any child of hers to chide her with bow- 
 legged records when he is grown. She knows that the 
 
 younger the child the more 
 promptly do bones bend in 
 this direction or that, ac- 
 cording to the treatment 
 they receive or the use 
 they are put to. 
 
 Indian mothers have 
 known this for centuries. A 
 certain tribe that admired 
 flat-headed men used to se- 
 cure these heads for their 
 boys by a clever contriv- 
 ance. They simply fastened a board by a hinge to the 
 head of the cradle and allowed it to press down upon 
 the forehead of the baby whenever he was strapped in 
 place. As months passed the small skull not only con- 
 tinued to grow but also set itself hard and firm in the 
 desired shape. And, once firmly set, there was never 
 any hope that the grown Indian could restore his head 
 to the perfect shape which it had when he was born. 
 
 THE MIDDLE FINGER is MEASURED 
 BY A CALIPER COMPASS 
 
BONE AND MUSCLE RECORDS 
 
 Even by accident bones often take on some unex- 
 pected and undesired shape. A man whom I know 
 had a narrow escape from a fate of this sort. As a 
 baby he suffered from colic, and his mother found that 
 he was quietest in his crib 
 when he lay on his stomach 
 with the right side of his face 
 on his pillow. Day after day, 
 therefore, he slept in the same 
 position. Then, to her dis- 
 may, one morning his mother 
 noticed that his head was a 
 queer-looking thing. It was 
 slightly flattened on one side 
 and well rounded out on the 
 other. She was in despair at 
 first, thinking that her child 
 was perhaps deformed for life. 
 But her good sense told her 
 that there was one thing to 
 do. She saw that the change 
 in shape was due to the fact 
 that the child lay always with the same side of his head 
 against the pillow. That side had been under pressure 
 while the other side had been growing. She therefore 
 tried to improve matters by making the youngster sleep 
 with his face turned the other way on his pillow. 
 
 CHINOOK BABY IN HIS CRADLE 
 
 The weight on his forehead will 
 
 help turn him into a flat-headed 
 
 Indian 
 
6 THE BODY AT WORK 
 
 For hours the first night the baby could not sleep. 
 He cried and even screamed. But he was so young, so 
 small, and so weak that he could not raise his own head 
 to turn it over. He was really at the mercy of his 
 mother; and the more she thought about it the surer 
 she was that to restore the shape of his head she must 
 compel him to sleep in a different position. Conse- 
 quently she was firm, and in the course of a few days 
 the boy could sleep as well on one side as on the other. 
 
 For many days, however, there was no change to be 
 seen in the queer little head. Nevertheless, after three 
 months the reward came. The woman saw that the 
 flattened side of forehead and head had grown out as 
 full and round as it should be. The two sides were 
 alike once more. She had learned her lesson, and 
 thenceforward the baby lay in his cradle with his face 
 turned about as often to the right as to the left. To-day 
 that boy is a college student. He weighs one hundred 
 and eighty pounds, and his head is as well shaped as 
 that of any member of the junior class. He has his 
 mother to thank for this; for if he had had his own 
 baby way, he would have ended with a head so queer 
 that he would have been ashamed of it. And, worst 
 of all, by the time he himself had made the discovery, 
 the bones of his skull would have been too firmly set 
 to be changed. Thus some of our bones and muscles 
 are trained by other people before we are old enough 
 
BONE AND MUSCLE RECORDS 7 
 
 to make decisions for ourselves. Yet, whoever is respon- 
 sible for results, two laws of bone growth should never 
 be forgotten : 
 
 1. Many bones can be compelled to take a bend 
 in this direction or that while the child is growing. 
 
 2. Almost no bone can be forced to make a new 
 bend after it is twenty years old. 
 
 But there is other training which is more complex and 
 for which we ourselves are responsible. 
 
 On a certain day two boys entered the same shop 
 and asked for work. The first boy was refused, the 
 second was accepted, and the explanation lay with the 
 bones and the muscles which had made different rec- 
 ords for the two bodies to which they belonged. The 
 first boy walked with a shuffle and had a slouching 
 body. Before he had spoken a word the business man 
 who met him was unfavorably impressed and ready to 
 reject him. 
 
 The second boy walked as if he respected his body 
 thoroughly. His head was erect, his shoulders well 
 squared, and each muscle gave the impression that he 
 was in the habit of doing things with energy. This 
 boy was accepted as promptly as the first was refused. 
 
 Imagine a man who needs the help of other men in 
 carrying on some undertaking. Then try to picture the 
 sort of body that will serve him best. Think how his 
 success or his failure will be influenced by bone and 
 
8 THE BODY AT WORK 
 
 muscle, by the way he stands and walks, by the way 
 he uses his back and arms and legs and feet. 
 
 Let two women enter a store or a schoolroom, a thea- 
 ter or a church. Which will be served most quickly, 
 she who shuffles as she walks, has crooked shoulders 
 and a head thrust forward, or the woman who steps for- 
 ward gracefully, who walks as if her body were her best 
 possession, as if it were her true representative ? Surely 
 the second woman is queen wherever she goes. With- 
 out question, at every stage of growth the body pro- 
 claims the story of what has happened to it and of all 
 that it has done with itself since it began to live. 
 
 The point of this chapter, then, is not that police 
 measurements of size and shape make very much 
 difference to us, but that it is more or less within our 
 own power, while we are growing, to make the records 
 which are to represent us the rest of our lives. 
 
 If a man by his own acts or his own carelessness 
 must live miserably in a shanty when he might have 
 lived gloriously in a palace, we are apt to blame him 
 more than we pity him. 
 
 The pages of this book will show that in a marvelous 
 way we are the architects of our own bodies. We shall 
 also learn how to help ourselves build the sort of house 
 that we care to live in, the body which we are proud 
 to acknowledge and which we are glad to see labeled 
 with our name in full. 
 
CHAPTER II 
 
 DANGER FROM THE SCHOOL DESK 
 
 For the sake of making discoveries about yourself, 
 stand before a mirror and study the 
 outline of your back, your chest, your 
 shoulders, and your legs. Try to stand 
 precisely as you do every day at home 
 and at school, so that you may get 
 a correct notion of the records your 
 bones and muscles have made for you 
 thus far in life. 
 
 Let your eyes be keenly critical. Are 
 you standing squarely on both feet? 
 Are your knees bent or straight? Is 
 your back erect enough to hold your 
 head up where it belongs, or does 
 your head droop forward so that your 
 chin sticks out too far in front ? Are 
 your shoulders on a level with each 
 other, or is one higher than the other? 
 Is your chest rounded out like that of 
 a soldier, or is it flat and curved in like a scoop be- 
 tween the shoulders ? Rub your hand across your back to 
 
 9 
 
 HE STANDS CORRECTLY 
 
 (Copied from Practical 
 
 Hygiene, by Alice 
 
 Ravenhill) 
 
IO 
 
 THE BODY AT WORK 
 
 see whether or not a corner of a shoulder blade reaches 
 out like a young wing starting from the wrong place. 
 
 If you can give creditable answers to these questions, 
 your future course is easy. Simply keep on growing as 
 you have begun, and when your bones 
 are hard you will have the shape you 
 wish. If, on the other hand, you are 
 not perfectly satisfied with what you 
 find, rectify each item of your posture 
 separately, while you still look at your- 
 self in the mirror. 
 
 Stand as nearly as you can as fol- 
 lows: both feet on the floor, each 
 bearing its own share of weight ; both 
 knees stiff ; both shoulders square and 
 on a level with each other. Draw in 
 your chin until the back of your neck 
 would touch a stand-up collar if you 
 had one on. Inhale a breath so full 
 and deep that your chest looks like 
 that of a drum major ready for his 
 regimentals. Now your back has its 
 correct shape for standing. It should 
 be slightly curved in its stretch from neck downwards. 
 
 Later in the day test yourself again. You are now 
 seated. Perhaps you are in the schoolroom. If you 
 have time for it, take different positions and note the 
 
 HE LESSENS HIS LUNG 
 
 CAPACITY 
 
 (Copied from Practical 
 
 Hygiene, by Alice 
 
 Ravenhill) 
 
DANGER FROM THE SCHOOL DESK 
 
 1 1 
 
 feelings in connection with each. First, sit with feet 
 squarely on the floor, back straight, head erect, and 
 chest raised. Are you comfortable ? Can you draw a 
 full, deep breath ? Test this thoroughly. 
 
 Now slip down in your seat, curve your head for- 
 ward, let your back be bent, 
 let your chest fall in, and 
 once more try to take a full, 
 deep breath. Notice that 
 here in the schoolroom, 
 where your brain needs ox- 
 ygen for its work, you have 
 reduced your supply by the 
 way in which you have 
 doubled up your lungs. 
 
 For the sake of variety 
 take another position. Sit 
 with one elbow on the desk, 
 or with one foot drawn up 
 under you, or with some 
 bend at the waist line that 
 will give a twist to the spine 
 near the hip. The objec- 
 tion to taking any one of these as the usual position is 
 that gradually the relation of the bones to each other 
 will be so altered as to give the body an undesirable 
 shape. In no wise does it harm any of us to twist this 
 
 HE CURVES HIS BACK AND CROWDS 
 HIS LUNGS 
 
 (Copied from Practical Hygiene, 
 by Alice Ravenhill) 
 
12 THE BODY AT WORK 
 
 way and that, to bend as far as we can in one direction 
 or another. Indeed, all such exercise is most whole- 
 some, provided no one position is taken often enough, 
 or held long enough, to become a habit. 
 
 Sidewise twists which have become permanent are 
 receiving much attention from doctors and school ex- 
 aminers to-day. These men claim that although the 
 large majority of the curves are very slight, and al- 
 though most of them will, in all probability, never 
 become serious, still it is not safe to allow a curve 
 either to form or to increase after it is formed, because 
 we cannot tell what the outcome may be. 
 
 Dr. F. A. Schmidt, a scientific writer in Germany, 
 says that Dr. W. Mayer examined the backs of three 
 hundred and thirty-six girls and found that one hun- 
 dred and eighty-nine of the number had what is called 
 lateral curvature of the spine. He found that girls 
 between seven and thirteen years of age had much 
 more trouble than those who were under seven, and 
 he concluded that the habits of sitting formed at the 
 school desk explained the difference, because the older 
 children had spent more hours, days, and years in the 
 schoolroom than those who were younger. 
 
 Another German investigator found that in a certain 
 group of children eighteen per cent of the boys and 
 forty-one per cent of the girls had these same curved 
 spines. This looks as if the girls of that group had 
 
DANGER FROM THE SCHOOL DESK 
 
 been more careless than the boys in the way they sat at 
 their desks. Or it may be that the boys had saved them- 
 selves by taking more exercise out of the schoolroom. 
 
 In 1907, in the great school at Rugby, England, out 
 of one thousand boys be- 
 tween the ages of thirteen 
 and fifteen, four hundred 
 and forty-five were found to 
 have more or less of a side- 
 wise curve to the spine. 
 
 In America the same dif- 
 ficulty overtakes children in 
 every public school. 
 
 Those who hear these 
 facts for the first time are 
 apt to be filled with alarmed 
 surprise. They wonder why 
 boys and girls who start life 
 with beautiful, symmetrical 
 
 bodies, should be allowed to CURVED BACK AND HOLLOW CHEST 
 
 develop backs With objeC- (Copied from Practical Hygiene, 
 
 .11 . i by Alice Ravenhill) 
 
 tionable curves in them. 
 
 The answer is that, until recently, the world of think- 
 ing people has been entirely ignorant of the actual state 
 of affairs. Few have understood the close connection 
 between twisted backs and school desks. Now, however, 
 the connection grows plainer every day. 
 
THE BODY AT WORK 
 
 Look round the schoolroom you are in and see how 
 many of the children are doing the best they can for the 
 spine. Draw your own conclusions from what you find. 
 Some schools are thoroughly wide-awake on this sub- 
 ject. They have regular 
 gymnastic exercises be- 
 tween recitations for the 
 express purpose of sav- 
 ing the children from 
 the harm which may 
 come through long- 
 continued sitting at the 
 desk. 
 
 It is absurd to grow 
 excited over the situ- 
 ation and to conclude 
 that we are about to be- 
 come a race of deformed 
 people, for now that both 
 
 
 HE TWISTS HIS BACK 
 
 If he takes the same position day after day, 
 
 some of the vertebrae will finally become 
 
 wedge-shaped. Habits of the school desk 
 
 may thus change his shape for life 
 
 (After Schmidt) 
 
 causes and cures have 
 been discovered there 
 is no remaining excuse 
 for any school of intelli- 
 gent children. Let them know the danger they run and 
 they will save themselves by the laws of prevention. 
 
 Follow for yourself the work of muscle and bone, and 
 understand what happens when a child gets into the 
 
DANGER FROM THE SCHOOL DESK 
 
 habit of sitting at his desk with elbow up on one side, 
 
 shoulder lifted, and body half screwed round. Notice 
 
 that if you tip up one hip the spine curves sidewise 
 
 as a balance. If you raise one shoulder it pulls the 
 
 spine accordingly. Evidently 
 
 each separate movement of the 
 
 muscles of the back brings its 
 
 result in the curves of the spine, 
 
 and the same curves, repeated 
 
 day after day at the same desk, 
 
 hold the bones and the cartilage 
 
 which lies between them in wrong 
 
 positions, until they are as truly 
 
 pressed into a new shape as was 
 
 the skull of the sleeping baby. 
 
 So far as health is concerned, 
 the main objection to these lateral 
 curves is that if they are allowed 
 to go on and become serious, 
 they will interfere with the suc- 
 cessful work of the large organs 
 of the body. Then, too, when a 
 curve becomes permanent although it may be small 
 the nerves themselves are often affected by it, and 
 the body suffers at the point which is supplied by those 
 nerves. A person enduring this pain may not know its 
 cause, but his ignorance will not save him from suffering. 
 
 CURVED BY THE WAY HE 
 is HELD 
 
 If his nurse will carry him as 
 
 often on one arm as on the 
 
 other, no harm will be done 
 
 to the vertebras 
 
i6 
 
 THE BODY AT WORK 
 
 \ 
 
 When a medical inspector passes through the school- 
 room or makes his special examination of your body, do 
 not be alarmed. Even if he tells you that you have 
 a little trouble with your back, keep calm and self- 
 
 possessed about it; for in any 
 case of this sort the director of 
 physical training in your school, 
 or some one else who understands 
 the laws of muscle action, will 
 give you definite directions as 
 to what you are to do in the line 
 of gymnastic exercises. And by 
 being faithful in carrying out 
 these directions you will straighten 
 your back. 
 
 But prevention is best of all. 
 Children may save themselves by 
 being careful to balance the exer- 
 cises which they allow the muscles 
 of their backs to take. All that is 
 habit, the boy will have a needed is a little knowledge and 
 
 crooked body when he is a firm purpose> Whoever allows 
 a man 
 
 (Copied from Practical Hygiene, himself to be shaped by undesir- 
 
 Q f 
 
 NOTICE HIS SHOULDERS 
 If this position becomes a 
 
 by Alice Ravenhill) 
 
 will have cause for keen regret in later years. But he 
 who, in his youth, controls his habits and shapes his 
 body with care, will never regret it. Four rules will help : 
 
DANGER FROM THE SCHOOL DESK 17 
 
 1. Do not sit day after day in the same twisted 
 position. When you have been seated in one way 
 for a while, then change and sit in some other way. 
 
 2. Do not carry a heavy weight of books on the 
 same arm back and forth from school every day. 
 Carry as few books as possible on either arm, and 
 let each arm do its share in holding the weight. 
 
 3. Do not carry a baby brother or sister on 
 the same hip every day. The weight just there 
 will tend to give a wrong twist both to your back 
 and to his. 
 
 4. If you must stand for hours at a stretch, learn 
 to rest one leg by using the other. Don't let one 
 side sag down from habit. Change sides. 
 
 It is best to keep free from every form of spinal 
 curvature by prevention ; but if, through ignorance, 
 you have been overtaken by it, you have a rare oppor- 
 tunity to prove for yourself what can be done with the 
 growing human body. You will succeed if you make 
 up your mind to it. 
 
CHAPTER III 
 
 MUSCLES CONTRACTING AND STRETCHING 
 
 The coal heaver round the corner has a superb set of 
 muscles over the working part of his back. They are so 
 well developed that, as he stands bent over his work, it 
 
 is evident that these muscles 
 give him a back of tremen- 
 dous strength. By their help 
 he shovels coal for hours at a 
 time through the days and the 
 weeks of the year. Moreover, 
 when he has finished his day's 
 work he does not seem over- 
 tired. He is still ready for his 
 joke and his laugh with his 
 children at home. He even 
 jokes at the expense of his 
 own back, for although it is 
 so well developed and so tire- 
 less, still the man himself frankly acknowledges that it 
 is sadly bent, and that by no effort on his part can* he 
 stand straight or walk as would please him best. He 
 says that that is the price he has had to pay for the 
 
 18 
 
 BENT BY HIS WORK 
 
MUSCLES CONTRACTING AND STRETCHING 
 
 kind of work he has chosen as a life occupation. More 
 people have round shoulders developed in some such 
 way than are troubled with any kind of lateral curvature 
 of the spine. 
 
 A bicycle rider whom I know 
 has a back quite as bent, although 
 from a different cause. It is mus- 
 cular, strong and efficient, but it 
 never looks well except when he 
 is working his legs fast on his 
 wheel. It is bent from the posi- 
 tion it has been allowed to take, 
 rather than from the work it has 
 done in that position. 
 
 Something must be wrong, how- 
 ever, and we wonder what it is. 
 Here are these men and multi- 
 tudes of others whose backs are 
 splendidly developed, but who are 
 so bent as to look almost deformed. 
 For years no one could entirely 
 explain the cause of the combi- 
 nation the strong but bent back. 
 
 At last, however, close observation and logical reasoning 
 have made the case clear. I give the explanation in the 
 fewest words possible. The value of this explanation will 
 be measured for us by the use we make of the law : 
 
 BENT BY BICYCLING 
 
20 THE BODY AT WORK 
 
 Muscles stay in the position in which they do their 
 heaviest work. 
 
 A man of my acquaintance who travels a good deal, 
 says that when, for a few weeks, he carries his suit case 
 persistently with the same hand, that shoulder becomes 
 an inch or an inch and a half lower than the other, 
 while, at the same time it becomes stronger. This shows 
 how a muscle can be lengthened even while it is being 
 strengthened. 
 
 Stretch a muscle out and work it hard, as a coal 
 heaver does when he curves his back over for the shov- 
 eling and the lifting of the coal, and those muscles, being 
 obliged to work hard, even while they are stretched, will 
 gain their strength in that position and will stay elongated 
 even when they are not at work. Let their size and their 
 strength increase while they are stretched and you have 
 given them their permanent shape. 
 
 Two oarsmen illustrate this law in opposite ways. 
 One does all his hardest rowing with a straight back, the 
 other with a back that is curved. Their work continues 
 day after day until each back is as strong and as muscu- 
 lar as the other. But see what the results are. One man 
 walks as if he had spent his boyhood curved over a 
 school desk without a thought about what might be 
 happening to his spine. The other man looks as if he 
 might have spent those same years at West Point with 
 officers and fellow-students who compelled him to stand 
 
MUSCLES CONTRACTING AND STRETCHING 
 
 21 
 
 straight whether he wished to or not. Yet the boyhood 
 of the two men may have been the same. Indeed, the 
 difference just now lies entirely with the two positions 
 in which they did their rowing. Their muscles, when 
 they walk, simply betray some facts 
 about their recent history. 
 
 Look at the hand of a piano 
 player, it is open because he al- 
 ways exercises it hard in that posi- 
 tion ; and the hand of the oarsman, 
 see how his fingers curl up as if 
 they were ready to grasp his oar 
 even when it is not in sight. An 
 oarsman's hand tells the story about 
 his occupation. 
 
 From the man who digs to earn 
 his daily bread on the farm or in 
 the coal mine, to the man who 
 climbs a mast and risks his life in 
 the tempest, through each occu- 
 pation of life the muscles of the body are called upon 
 to do their hardest work in special positions. And it 
 sometimes seems as if numberless human beings would 
 have to submit to their fate and accept muscles which 
 their work has forced on them; for after a man has 
 chosen his life work he cannot leave it simply because 
 he objects to the shape which it is giving to his body. 
 
 BENT BY AGE 
 
22 THE BODY AT WORK 
 
 Fortunately, however, there is a happy outlook even 
 for such people as are obliged to work with their backs 
 bent, for there is another important fact about this law 
 of contracting and stretching. I give it concisely: 
 
 Brief, vigorous exercise in the right position will undo 
 much of the harm of long-continued exercise in the wrong 
 position. 
 
 If a man who works in a bent posture all day will 
 spend five minutes a day in taking vigorous exercise 
 with his back straight, alternately tightening hard and 
 then relaxing the muscles of his back and neck, he 
 will find that, within one month, there will be an im- 
 provement. By this simple device a man may save him- 
 self from his rounded back and be able to hold his head 
 where it should be. 
 
 Let the oarsman who objects to hands that curve like 
 stiffened claws spend several minutes each day in first 
 extending his fingers forcibly, then in relaxing them, 
 and he will be sure to see results. 
 
 From these facts we learn that by the vigorous exer- 
 cise of one set of muscles for a few minutes each day, 
 we may be able to overcome the harm which is done by 
 the long-continued plodding work of another group of 
 muscles. 
 
 It often happens that the muscles of the chest be- 
 come thin and flabby for lack of exercise, even while the 
 back has become very strong. But these muscles may 
 
MUSCLES CONTRACTING AND STRETCHING 23 
 
 be saved. Throw the shoulders well back and exercise 
 chest muscles hard in this position. Exercise them while 
 they are thus stretched and they will grow large and 
 prominent in spite of what the man's occupation may be. 
 In this work of changing the shape and the power of 
 a muscle the greatest strain must be put on the last 
 third or the last quarter of the contraction which it 
 makes. Remember that each muscle is inclined to stay 
 in the shape which it takes when it does its hardest 
 work ; in other words, the law of the body is that doing 
 a thing makes the body shape itself to that act. 
 
CHAPTER IV 
 
 THE MUSCLE ITSELF 
 
 The audience was greatly interested, for the doctor 
 who gave the lecture had just said that, with very little 
 
 trouble, each man present 
 could increase the size of his 
 arm three quarters of an inch 
 within one month, and could 
 increase his chest measure an 
 inch and a half during the 
 same length of time. Those 
 who listened were business 
 men, and they were specially 
 pleased with the part of the 
 lecture which told them how 
 they might set to work to se- 
 cure this astonishing growth 
 
 EXERCISE FOR THE BICEPS f , , 
 
 for themselves. 
 
 To show what he meant, the lecturer asked his friend, 
 a medical student, to illustrate the points one by one as 
 he himself explained them. The student was well-knit 
 and well-built. No unnecessary fat concealed the shape 
 
 of his muscles, and he was ready to show the other 
 
 24 
 
THE MUSCLE ITSELF 25 
 
 men what they also might do in behalf of their own 
 development. 
 
 For a while it sounded as if the whole talk were to be 
 a lecture on the size and shape of different muscles; for 
 the doctor asked his friend to show his muscles one after 
 the other in quick succession. " Now," said he, " show 
 us the effect on the biceps of rotating the arm; the 
 forearm; now the leg, the big muscles; show that 
 tensor. Now again will you 
 go through four or five exer- 
 cises that bring into play in 
 succession first one arm, then 
 the other, and so on ? " 
 
 The student acted on the 
 suggestions as fast as they 
 were given. His smooth back 
 
 , . . WELL-DEVELOPED MUSCLES 
 
 and arms gave no sign of 
 
 separate muscles while he stood quietly waiting to be 
 told what to do. But as soon as he followed directions 
 and used arm, leg, back, or shoulders, there sprang into 
 view a succession of splendid muscles that seemed to 
 have been lying in ambush under the skin. 
 
 From his intense expression it was evident, however, 
 that in order to force these muscles into action and into 
 sight, the young man fastened his utmost will power 
 and attention on them. In doing this his joints had to 
 stiffen themselves for the stronger resistance, while at 
 
26 THE BODY AT WORK 
 
 the same time the muscles of the entire body seemed to 
 be brought into active exercise. They worked together, 
 although the special force of each exercise was of course 
 centered on the muscle which was being developed. 
 
 In all this the student held no apparatus, but he used 
 arms and legs as if he were pulling against some invisi- 
 ble weight. He was, in fact, pulling against the force of 
 his own other muscles, antagonistic muscles they are 
 
 called. Try this for yourself 
 with your forearm or with 
 your back. Decide to bring 
 out one muscle and see how 
 many others are called into 
 action. 
 
 The lecturer then explained 
 that muscles can be developed 
 in this way with no apparatus 
 
 EXERCISE WITHOUT APPARATUS ' . 
 
 whatever. He said that the 
 
 power lies in making certain muscles pull against their 
 antagonistic muscles. As he gave his directions he 
 added that muscles must pull as hard as possible for 
 a few seconds at a time, must then let go completely, 
 then pull again for a few seconds, and so keep up the 
 alternation for five minutes in the morning, for five min- 
 utes at night, and for ten minutes a day between times. 
 Men who proposed to develop arm or chest could, he 
 said, put in the extra ten minutes whenever convenient 
 
THE MUSCLE ITSELF 27 
 
 It seems that the different pulls do not need to be in 
 close succession, but may be slipped in anywhere during 
 the day. The whole process of developing a particular 
 muscle or set of muscles may 
 thus be carried on without 
 apparatus, without gymnas- 
 tics, without fuss or feathers 
 or display in any direction. 
 The student testified that 
 what he had done for himself 
 in this way had increased the 
 size of his own arm an inch 
 
 . . HE DEVELOPS ARM MUSCLES 
 
 within a single month. 
 
 As for securing really big muscles, however, anything 
 
 enormous is a disadvantage rather than an advantage in 
 
 the health line. Still the fact 
 that up to a definite limit we 
 have the power to increase 
 the size of arm and chest and 
 leg proves once again how 
 truly each of us is master 
 and architect of the body we 
 are building. 
 
 TAKING THE MEASUREMENT ^ , . , - . , 
 
 But what about the material 
 
 itself the substance out of which the body piles a 
 muscle into shape and compels it to increase in size 
 whenever it is forced to do unusual work? 
 
28 
 
 THE BODY AT WORK 
 
 Get a piece of lean corned beef from the butcher; 
 have it boiled thoroughly; place a board over it and 
 press down upon it hard enough to squeeze out all the 
 liquid; remove the board, and with a needle of some 
 sort pick apart the fibers as well as you can. Pick them 
 
 away from each other 
 into finer and finer 
 threads until you think 
 you have reached the 
 limit in size. 
 
 Now if you can get 
 a good magnifying 
 glass, use it in examin- 
 ing one of these bits 
 of beef muscle. You 
 are able to pull them 
 apart because the out- 
 side wrapping of each 
 has been changed by 
 boiling. 
 
 However large or 
 small a muscle may be, and wherever that muscle does 
 its work, whether in creatures that walk or fly or swim, 
 every active muscle is made up of fibers wrapped to- 
 gether in bundles. Shapes are different ; size varies from 
 those that draw an eyelid up and down to those that 
 kick a football to its goal ; location is different ; strength 
 
 MUSCLES OF DIFFERENT SHAPE 
 (After Schmidt) 
 
THE MUSCLE ITSELF 
 
 29 
 
 and power of endurance are different; but each muscle 
 
 that has ever been studied has been found to be made 
 
 up of fibers. A few of these are 
 
 wrapped together as a small bundle. 
 
 Small bundles are gathered into 
 
 bundles that are larger. Large 
 
 bundles become larger yet; and 
 
 thus from smaller to larger are the 
 
 muscles built up. Each is a bundle 
 
 of other bundles ; each is adapted 
 
 in size and shape to the special 
 
 work which it must do ; and every 
 fiber in the bundles, 
 
 large and small, is inclosed in its own sarco- 
 lemma. This sarcolemma, then, is simply an 
 outer wrap which separates each fiber from 
 all the others. In addition, however, there 
 is a close network of substance called con- 
 nective tissue, which holds the individual 
 fibers together. In this connective tissue are 
 the tiny blood vessels and the slender nerves 
 which supply blood and stimulus to each 
 smallest fiber of the largest as well as of the 
 
 INDIVIDUAL 
 MUSCLE FIBERS 
 
 END OF A 
 MUSCLE FIBER 
 
 help form the sma llest muscles of the body. Fine threads 
 
 tendon 
 
 of connective tissue also stretch away from 
 each end of the muscle fibers and help form the tendon. 
 Thus, although each separate fiber is a part of the muscle 
 
30 THE BODY AT WORK 
 
 as a whole, it also seems to be an independent small 
 center of power doing its own independent work. 
 
 The truth, however, is that no single fiber carries its 
 independence very far. Generally when its neighbors 
 receive your command to go to work, it receives the 
 same command. When they rest, it rests too. When 
 they are destroyed by suffering, age, or death, it endures 
 all that they endure. Yet, after all, the work of the mil- 
 lions of fibers which are held 
 together by connective tissue 
 in a single muscle is really the 
 sum of the work which the fibers 
 do separately. 
 
 More than this, it is the 
 amount of connective tissue be- 
 
 A BUNDLE OF MUSCLE FIBERS 
 
 ,-, , . tween the fibers that explains 
 
 Each is covered with its own 
 
 sarcoiemma ; connective tissue the difference between tough 
 
 is between the fibers , , TTT . 
 
 and tender meat. With age and 
 
 with exercise this tissue gradually thickens its substance 
 during life until finally certain muscles become too tough 
 to be eaten without long boiling. 
 
 A spring chicken is tender because its tissue has not 
 been toughened by work. Tender steak comes from that 
 part of the animal which has had little exercise. When, 
 therefore, we speak of tough and tender meat we really 
 refer to muscles in which the connective tissue has been 
 toughened. 
 
SUPERFICIAL MUSCLES OF THE BODY 
 
 Each is fastened to bones that lie underneath 
 
 3 1 
 
32 THE BODY AT WORK 
 
 These facts apply not only to the muscles of those 
 animals that are killed by human beings for food, but 
 also to our own arms and legs. Let an athlete bend up 
 his arm for your benefit. You may try to press it with 
 your hand and it will resist you almost like a piece of 
 wood. This is no mystery to you, for you understand 
 that each fiber in that muscle has been toughened by 
 use. If the muscle itself were found in the shop of a 
 butcher and were offered for sale, a wise cook would 
 refuse to buy it. He would complain that even boiling 
 would not make it tender. 
 
 These muscles which we have been studying belong 
 to the skeleton. They are always attached to bones and 
 are therefore called skeletal or voluntary muscles. There 
 are indeed two classes of muscles : 
 
 1. Voluntary muscles, of which there are five 
 hundred. They are called voluntary because each 
 is under the power of our will. Through them we 
 walk and run and climb and swim; through them 
 we talk and sing and play the piano and cover our- 
 selves with glory on the athletic field. They serve 
 us when we give our commands. Not so, however, 
 with the second class. 
 
 2. Involuntary muscles. These form the heart 
 and are also in the walls of the arteries and of the 
 alimentary canal, the food tube. They are deaf 
 when we command, but they continue to be busy 
 
THE MUSCLE ITSELF 33 
 
 whether we are asleep or awake ; whether we stand 
 or sit; whether we laugh or sigh or cry, run or 
 climb or swim. Whatever we do, they are unceas- 
 ingly occupied with the internal work of the body, 
 pumping the blood round through heart and 
 blood vessels, caring for the food we eat, and carry- 
 ing on those central, vital processes of life over 
 which we have no conscious control. 
 Taken as a whole, the muscular machinery of any 
 human being weighs as much as all the rest of his body 
 put together and weighed in a lump. A few separate 
 muscles are given in the picture, but there is no special 
 reason why we should learn their names by heart. 
 Nevertheless the biceps is not easily forgotten. It is the 
 muscle best known to every boy, for it may give him 
 pride or disgrace him, according to the pulling power 
 which has been developed in it by its master. 
 
CHAPTER V 
 
 STIFF SUPPORT FOR GROUPS OF MUSCLES 
 
 A certain teacher who owned a skeleton was in the 
 habit of throwing it over his shoulder when he carried it 
 from the storeroom where he kept it to the lecture room 
 where he showed it to his students. And as he walked 
 it hung from his back as a clattering set of dangling 
 bones. It is true that the separate bones were held to- 
 gether at the joints by artificial contrivances; but that 
 was all. By no chance could the skeleton have stood 
 on its own unaided legs. Those who saw this group 
 of bones for the first time understood as never before 
 that bones are as dependent on ligaments and muscle 
 to keep them together as are tendon and muscle de- 
 pendent on bone to hold them in place. 
 
 Examine a bone fresh from the butcher's. Notice the 
 outside, firm and closely woven, as it has to be, to 
 supply a surface for muscles to hold to. Look at the in- 
 side. There we find looser texture. We know now how 
 it happens that the bone is not only large and strong 
 but light and firm. It is indeed by no means a solid 
 thing. A magnifying glass shows the spaces even better 
 yet. You may now see smooth channels on the outside, 
 
 34 
 
OF THE 
 
 UNIVERSITY 
 
 OF 
 
 THE CENTRAL SUPPORT OF THE HUMAN BODY 
 
 A, skull (composed of 22 bones); , spinal column (composed of 33 vertebrae); 
 C, sternum or breastbone; /), ribs (12 on each side); , clavicle; F, humerus; 
 G, radius; //, ulna; /, carpal (7 bones in each wrist and ankle); /, metacarpal 
 (5 bones in the palm of each hand and instep); K, phalanges (14 bones that form 
 the fingers and the toes of each hand and foot) ; Z, pelvis (composed of 4 bones) ; 
 J/, femur ; A 7 ", tibia ; O, fibula 
 
 35 
 
THE BODY AT WORK 
 
 along which the blood vessels ran, and tiny openings 
 from the surface to the interior, into which the smallest 
 blood vessels went, to keep up the life of the bone. 
 
 A chemist will take the same bone and study it in 
 another and a different way. He will keep it in acid 
 for a while and will then tell us that he has taken 
 
 all the lime out; that he 
 has left nothing but gela- 
 tin. He may tie it into a 
 knot and let us see how 
 pliable it is. Taking an- 
 other bone, he will hold 
 it in fire for a while, and 
 when w r e touch it the 
 whole structure will go to 
 
 BONE CUT LENGTHWISE (A) AND j jj k ] f R 
 
 CROSSWISE (B] 
 
 , ., " That is mostly lime," he 
 
 Blood vessels and nerves run through the J 
 
 canals, and these canals are joined to each Will tell US J u I have 
 other by channels yet more minute , , . 
 
 burned out the organic 
 
 matter which becomes gelatin when boiled." A cook 
 will take a bone with no meat on it, will boil it for 
 several hours, set the liquid away to cool, and when it 
 is cold she will have a thick jelly to add to her soups. 
 It is gelatin made from the bone. From these and other 
 experiments we learn that bones are made up of lime 
 and of an animal substance, which becomes gelatin after 
 being cooked. We also learn that in old age bones 
 
STIFF SUPPORT FOR GROUPS OF MUSCLES 37 
 
 contain the most lime, and that the younger the child 
 the less lime is there in his bones. 
 
 It appears that the proportion of lime increases from 
 year to year through life, until finally the entire system 
 of bones becomes too brittle to make it safe for aged 
 people to risk even so small a thing as a tumble on the 
 sidewalk. Many an older bone has snapped off short 
 where a younger bone would have saved it- 
 self by bending a trifle. 
 
 This brings us back to the subject of the 
 reason why children have the power to in- 
 fluence the shape of their bones while they 
 are young. The animal part not only pre- 
 vents bones from being brittle, but it keeps 
 
 ,1 TIT TIED IN A 
 
 them pliable. KNOT 
 
 Knowing this fact, I applied it to the case After acid has 
 of a friend of mine. She was getting a hoi- taken the lime 
 
 from it 
 
 low chest and I told her how to save herself. 
 " It will be hopeless after you are twenty," I said. " But 
 you are only twelve now. Your bones are still pliable. 
 If you will raise your chest with vigor, fill your lungs 
 with air, hold yourself in this position for three or four 
 seconds at a time and do it many times a day, you will 
 compel your bones to take the shape for which you 
 will be thankful the rest of your life." I suggested that 
 she give special attention to the matter on the way to 
 and from school each day. She liked my scheme so 
 
38 THE BODY AT WORK 
 
 well and practiced it so faithfully, that within a month 
 the curve of her chest had improved. Cities are full of 
 women who, if they could thereby im- 
 prove their appearance, would gladly 
 take hold of their bones one by one, 
 and pinch and pound them into a de- 
 sired shape. Such women have grown 
 up without knowing what we have 
 learned already, that during youth, 
 through the aid of muscles and firm 
 determination, the relation of bones to 
 each other may be quietly turned in 
 this direction or that according to our 
 own desire. 
 
 Although young bones are pliable, 
 they are nevertheless firm enough to 
 be the central support of the entire 
 body of the youngest child. See a 
 baby kick his small legs and thrash 
 A BONE c7 T his arms about. His bones are not yet 
 THROUGH LENGTHWISE strong enough to bear much weight, 
 
 The outer layer is com- ^ ^ supp l y j ust as many points 
 pact and firm, the inner * rr J J 
 
 substance is a network for muscles to hold to aS do older 
 of canals and spaces; . ^, , , 
 
 thus are bones both light bones. They also have just as many 
 
 and strong different shapes as they will ever have. 
 
 Each bone is as important to the body of a child as to 
 
 that of a man, and ignorance about them is a misfortune. 
 
STIFF SUPPORT FOR GROUPS OF MUSCLES 
 
 39 
 
 Cervical 
 
 Thoracic 
 (orDorsal] 
 
 In so far as you can, feel of your own bones and de- 
 cide for yourself why each has its own particular shape. 
 You will find long bones for legs 
 and arms ; flat bones for shoulder 
 blades, breastbone, and hips ; curved 
 long bones for the ribs ; curved flat 
 bones for the skull; and you will dis- 
 cover that these latter are so close- 
 ly joined together that your head 
 seems like a solid, single bone. There 
 are queer, jagged bones, one above 
 the other, in a column for the back, 
 and many small bones of hand and 
 foot deftly held together, each doing 
 its part in stiffening up the body 
 and in making it serviceable to us. 
 
 Baby and man alike have the 
 same number of pieces to the skele- 
 ton, but the names of our two hun- 
 dred separate bones are of no vital 
 importance to us. Still the picture 
 gives a few, because it seems almost 
 discourteous to label such useful 
 articles as nothing more than long Ea ? h 8 rou P of vertebr * has 
 
 its special name 
 
 and short and flat and crooked bones. 
 
 Most important of all, perhaps, is the graceful column 
 of the spine. Many a man has lived for years without 
 
 Lumbar 
 
 Sacral 
 
 A SIDE VIEW OF THE 
 SPINAL COLUMN 
 
: BODY AT WORK 
 
 VERTEBRA SEEN FROM 
 
 ABOVE 
 
 an arm, without a leg, without bones of various size and 
 shape ; but no man has ever been able to live for a 
 moment without that pile of thirty-two small bones 
 
 that holds his head erect, that 
 keeps his ribs in place, and that 
 guards the treasure of his spinal 
 cord. 
 
 In this spine each separate 
 vertebra is held to the one above 
 it and to the one below it by 
 muscles and ligaments on each 
 side, and because of their muscles 
 and ligaments these individual vertebrae are no more 
 responsible for the shape they take, or for the twists and 
 curves they join in making when a gymnast bends his 
 back from side to side, than are 
 the dumb-bells and the pulleys 
 which the same gymnast uses ; for 
 the bones of the spine simply rock 
 back and forth upon each other 
 according as muscles on this side 
 or that give the needed pull. 
 
 Just here recall a few facts. As 
 we know, young bones are largely 
 cartilage ; they take new shapes if they are put under 
 special, oft-repeated pressure. A child at a school desk 
 easily gets into the habit of sitting with the vertebrae 
 
 VERTEBRA SEEN 
 
 FROM THE 
 
 SIDE 
 
STIFF SUPPORT FOR GROUPS OF MUSCLES 41 
 
 pressed against each other at the same angle every day. 
 Small muscles do the pulling; they grow strong as they 
 are exercised. In the meantime, also, the separate verte- 
 brae are yielding to pressure. On one side they are grow- 
 ing thinner ; on the other side, not being pressed upon, 
 they grow thicker. The result is inevitable. Some of 
 
 BLOCKS TO SHOW HOW THE VERTEBRA ARE HELD TOGETHER 
 BY LIGAMENTS AND MUSCLES 
 
 /, ligament; 7/2, muscle 
 
 the bones of the back will become wedge-shaped; and, 
 sad to say, a back that has developed wedge-shaped 
 vertebrae vertebrae that have kept their wedge-shape 
 until they are hardened for life can never hope to be 
 straight again. 
 
 Certain other bones may, however, be changed by 
 what they are compelled to do. Suppose you decide 
 that you wish those that are larger and rougher. You 
 
WEDGE-SHAPED VERTEBR/E 
 Pressure was too often on the same side 
 
 42 
 
STIFF SUPPORT FOR GROUPS OF MUSCLES 43 
 
 may travel a straight road to that definite end. Work 
 the muscles which are fastened to these bones ; work 
 them hard ; be persistent and the result will come. 
 
 In studying human skeletons it is not difficult to pick 
 out the bones of such persons as did vigorous muscular 
 work by their heavier and rougher character, while the 
 thin walls and fragile internal substance of other bones 
 show that the muscles of the arms and the legs were 
 paralyzed or wholly useless. 
 
 Evidently, then, active exercise leaves its mark even 
 on the bony part of the body. Thus, without making 
 any close examination of our own separate bones, we 
 may know, by the exercise we give them, what their 
 prospects are year by year. 
 
CHAPTER VI 
 
 BONDAGE AND FREEDOM FOR THE FEET 
 
 As I looked at the small, deformed feet of our friend 
 the Chinese lady, I easily imagined what had happened 
 
 CHINESE SHOES Two AND A HALF INCHES LONG 
 The huge ankle shows how deformed the foot really is 
 
 to the bones that made up the bulk of the huge ankle 
 above the shoe. No one saw this ankle. All we saw 
 
 44 
 
BONDAGE AND FREEDOM FOR THE FEET 45 
 
 was the dainty, handmade shoe two and a half inches 
 long, embroidered in silk of lovely shades, and made of 
 cloth and silk above a leather sole. 
 
 For hundreds of years Chinese custom demanded 
 that all the women of the upper classes in the empire 
 should hobble through life on deformed feet. Some feet 
 were larger, some were smaller, but in certain regions 
 the most stylish shoes were two and a half inches long. 
 This, then, was the size of foot which the ladies wished 
 to have. To secure it, a mother began to bind the feet of 
 her daughters 
 when the girls 
 were five or 
 six years old. 
 Often the girls 
 
 THE BONES OF THE FOOT 
 
 themselves 
 
 wished to have this done. Nevertheless the bandages 
 were drawn so tight that, night after night, young girls 
 have cried themselves to sleep in China because their 
 feet in their bandages hurt them so. 
 
 Almost never, however, were the bandages left off. 
 They were changed from time to time. But when they 
 were put on again they were pulled ever tighter, until, 
 in the course of years, the child secured the foot which 
 could never again help her by the movement of the 
 bones which formed it. The toes had been drawn in 
 under the foot; the heel had been drawn forward to 
 
46 THE BODY AT WORK 
 
 meet them; muscles and tendons had been kept from 
 growing, while the bones themselves had been obliged 
 to take strange new shapes as they fitted themselves 
 into such space as they could get. 
 
 When I saw my friend the Chinese lady, her feet were 
 set for life. They gave her little discomfort, and she her- 
 self now took entire charge of their binding. Until she 
 dies, however, she must hobble through her duties and 
 her pleasures almost as helpless as if 
 her feet were cut off at the ankles. 
 
 Fortunately for China, the 
 government has now for- 
 bidden foot 
 binding 
 throughout 
 the empire. 
 
 BONES AND LIGAMENTS OF THE FOOT AND ANKLE 
 
 At last, 
 
 therefore, the girls of the land may sleep in comfort, 
 and the future ladies of the Celestial Empire may walk 
 about with such ease and grace as can only come when 
 the entire foot is at the service of the body. 
 
 Even in other lands than China there is often lack of 
 comfort, while very often all trace of grace is also lack- 
 ing. When you see your own bare foot to-night com- 
 pare its natural shape with the shape of fashionable 
 shoes. Remember the following facts and decide what 
 the sensible course of action is: 
 
BONDAGE AND FREEDOM FOR THE FEET 
 
 47 
 
 1. Each foot is made up of twenty-six small bones. 
 
 2. These bones are joined to each other by liga- 
 ments and muscles. 
 
 3. No foot can be in thoroughly good order, neither 
 can it exercise itself with ease, unless each muscle, 
 bone, and ligament is allowed to move with freedom. 
 
 4. If the arch of the foot is flattened, health is 
 apt to suffer. Indeed, it is so serious a matter to be 
 flat footed that men with this 
 
 handicap are refused admit- 
 tance to the United States 
 army. Test the condition of 
 the arch of your own foot by 
 dipping the bare sole lightly 
 in water, then pressing it on 
 blotting paper. The imprint 
 made will show whether the 
 foot is flat or arched. Those 
 who stand still for hours every 
 day are in danger of flattening 
 their feet. While they stand they should therefore 
 save the arch by resting the weight of the body first 
 on one foot for a while, then on the other. If you 
 have any tendency to flat feet, help yourself by the 
 following exercise. Stand with toes turned inwards, 
 and while in this position rise as high as you can 
 on your toes. Do this one hundred times, twice a 
 
 A B 
 
 FOOTPRINTS 
 
 A, an arched foot; B, a flat 
 foot 
 
 (After Schmidt) 
 
48 THE BODY AT WORK 
 
 day; or, instead of counting, rise and fall on the 
 toes until the muscles are tired. 
 
 5. A young foot grows by day as well as by 
 night, and should never be cramped when it is in 
 use. This does not mean that a shoe should be too 
 loose for comfort. It means that the foot is one of 
 the most useful pieces of machinery we have, and 
 that we are in better health and have a more 
 graceful walk when our feet are not uncomfort- 
 ably hampered by our shoes. 
 
 A WOMAN'S FOOT DEFORMED BY FASHIONABLE SHOES 
 (After Schmidt) 
 
 It is a sad fact that multitudes of men and women 
 would be filled with confusion if they were obliged to 
 show the shape of the feet they have secured for them- 
 selves. The explanation of the shape lies, of course, in 
 the shoes they have worn. 
 
 The best health of the foot calls for attention to the 
 following points: 
 
 1. Wear shoes with soles as broad as your foot 
 is when you stand with no shoe on. 
 
 2. Do not lace your shoes so snugly about the 
 ankle that the pressure will interfere with the 
 
BONDAGE AND FREEDOM FOR THE FEET 49 
 
 circulation of blood. Cold feet often come from 
 tight shoes, tightly laced. 
 
 3. Let the heels of your shoes be broad and low. 
 
 A B c 
 
 THE SHAPE OF THE FOOT AND THE SHAPE OF THE SHOE 
 
 Dotted lines show the natural shape of the foot ; solid lines show the sole 
 of the shoe. A, correct shape; B, the large toe is drawn in too far; C, 
 the shoe is too narrow. If you wish a comfortable and a well-shaped shoe, 
 get one that is wide enough, but longer than you need. This will give you 
 the effect of having a slender foot 
 
 4. Never wear tight garters. They interfere with 
 the movement of the blood through the blood vessels, 
 
 5. Remember that tan shoes are rather better than 
 black shoes for summer wear because they do not 
 keep the feet so warm. 
 
50 THE BODY AT WORK 
 
 6. Keep the feet dry and warm, but, if possible, 
 avoid overheating them. 
 
 7. Be sure that your shoes are large enough to 
 give your toes as well as your ankle a chance to 
 move and to be useful when you walk. 
 
 When the school children of the world turn their seri- 
 ous attention to the subject, and put into practice what 
 they know about healthy feet and about shoes of the 
 proper shape, they will form an army which will have 
 the power to lead the fashion of the world in sensible 
 shoes. 
 
CHAPTER VII 
 
 ASSISTANCE FROM JOINTS 
 
 During the summer of 1905 the following item ap- 
 peared in the New York Times. 
 
 ELEPHANT'S ANKLE SPRAINED 
 ALICE SLIPS ON A BANANA PEEL AND GETS A BAD TWIST 
 
 Alice, the big elephant in Bostock's at Coney Island, has a sprained 
 ankle. It is a bad sprain, too, mainly because it is a big one ; there 
 is nothing slender about Alice's ankles. Alice was crossing a gangway 
 into the arena when she slipped on a plebeian banana peel. 
 
 Alice saved herself from falling by winding her trunk around the 
 leg of her mate, Roger. Alice's ankle is now itf a big plaster cast, 
 
 which makes her leg look like a huge fireproof pipe. 
 
 i 
 
 No doubt Alice, the elephant, suffered as much from 
 her sprained ankle as did my friend Alice, the human 
 being, who sprained her ankle at about the same time 
 by slipping on another banana peel. In each case liga- 
 ments that held the bones in their sockets and tendons 
 that held the muscles to the bones were more or less 
 pulled from their firm fastenings. And when a pull does 
 as much mischief as that, recovery is often slower than 
 in the case of a broken bone. 
 
 51 
 
LOWER LEG WITH ITS 
 
 MUSCLES AND TENDONS 
 
 (After Schmidt) 
 
 THE BODY AT WORK 
 
 Bend your own ankle in every pos- 
 sible direction and learn what you 
 can about it from your sensations as 
 you twist it. Draw up the muscles 
 in the calf of your leg so hard that 
 you think you feel the spots where 
 they are fastened to the bones above 
 and below. Now recall facts which 
 you know 7 , and decide what is taking 
 place. Remember that muscles end 
 in tendons, and that it is by its ten- 
 don alone that a muscle is able to 
 move the bone which supports it. 
 
 For the muscle of the calf of the 
 leg, tendons are fastened to the lower 
 end of the thigh bone and to the heel 
 bone, and the work of contracting 
 is done between the two firmly held 
 points. Through this muscular con- 
 traction we walk and jump and run 
 to win the race or to take our exer- 
 cise. Tendons must be strong indeed 
 when they refuse to give way even 
 under the tremendous strain which 
 is put upon them. Follow the facts 
 about the biceps. It is fitted for one 
 particular kind of work, and it does 
 
ASSISTANCE FROM JOINTS 
 
 53 
 
 its work through the help of tendons which hold one 
 end of the muscle to the shoulder, the other 
 end to a bone of the forearm. When the 
 muscle contracts the lower bone is drawn up, 
 because, although the tendons themselves do 
 not contract, they cling to the 
 
 bones and thus help do the pull- jt*5=or 
 
 ing. Without tendons, indeed, 
 
 no muscle could ever move a 
 
 bone. Muscles of the back are A THE BICEPS 
 
 held to the spine, which they //\ MUSCLE 
 
 Control by tendons; neck mUS- When it contracts the lower bone 
 
 is drawn up ; the dotted line shows 
 cleS hold the head in place that the muscle is then thicker and 
 
 by tendons; and each of the 
 
 twenty-four ribs has its own supply 
 of muscles and tendons. By the 
 contraction of the muscles the ten- 
 dons pull the ribs up where we 
 wish them to be. 
 
 The serious part of strained ten- 
 dons is that the union of tendon 
 and bone is so close that, in a bad 
 
 MUSCLES BETWEEN THE RIBS sprain, the outside covering of the 
 
 When the muscles contract bone itself is Sometimes pulled 
 the ribs are drawn up away w j th the tendon> When th j s 
 
 happens a sprain is a far more serious affair to cure 
 than a clean-cut bone break ; for the broken ends of a 
 
54 
 
 THE BODY AT WORK 
 
 bone knit together far more readily than do the torn 
 
 ends of a tendon. 
 
 After all, however, the ligaments and bone surfaces 
 
 are quite as important to us as the tendon, because they 
 
 determine the direction in which a bone must move. 
 
 Some of them allow movement in one direction, some 
 
 in another. Prove this for 
 yourself. By every twist that 
 you can make, try to decide 
 where your joints are and 
 what style of joint each one 
 is. You will find that some 
 work back and forth like a 
 hinge, while others have the 
 power to move back and forth 
 and sidewise too. The differ- 
 ent kinds of movement are 
 the result of different kinds 
 
 Bone 
 tube 
 
 Bone 
 covering 
 
 MUSCLE ENDING IN TENDON; TENDON of joints. Each is needed in 
 
 FASTENED TO BONE fa part i cu l ar p l ace . 
 
 Begin with the hinge joint 
 
 where your skull is joined to the upper end bone of the 
 spine. This allows you to bend your head up and down, 
 and nothing more. But just below, bet ween -the next two 
 bones, is a joint of another sort. This allows you to turn 
 your head from side to side. Thanks to the two joints 
 acting as one, you can move your head in every direction. 
 
ASSISTANCE FROM JOINTS 
 
 55 
 
 Whirl your arm round and round and know that you 
 are using the most movable joint in the entire body. It 
 is a so-called ball-and-socket joint. The hip is supplied 
 with another of the same kind. 
 
 When we think of the work which the hip and the 
 knee have to do for us, and of the 
 strain we are ready to put on them at 
 any moment, we understand why the 
 hip and knee joints should be among 
 
 HIP JOINT DRAWN OPEN 
 
 Notice the ligament which holds the ball in 
 its socket 
 
 BONES AND JOINTS 
 OF THE LEG 
 
 the firmest and the strongest points of the whole body. 
 
 The knee itself is a wonderful structure. And here 
 
 we have an admirable chance to study ligaments. They 
 
 are firm and white and tough, being in all this quite like 
 
THE BODY AT WORK 
 
 THE BACK OF THE KNEE JOINT 
 (After Schmidt) 
 
 tendons. Moreover, when 
 once torn they are as slow 
 to heal as is a tendon. 
 Ligaments do the work 
 of holding bones to each 
 other, whereas tendons 
 hold muscles to bones. 
 
 The great hinge joint 
 of the knee is supplied 
 with ligaments which al- 
 low it to bend one way, 
 but which absolutely for- 
 bid any bending in an 
 opposite direction. If it 
 were not for the stout 
 ligaments which 
 hold the bones 
 
 together in a definite relation, our 
 knees would bend backwards and for- 
 
 wards with equal ease, and walking \ 
 
 would be forever out of the question. 
 
 Elbow as well as knee, fingers as 
 well as toes, all act on the plan of 
 the hinge. 
 
 Two kinds of joints are thus seen 
 to be most prominent in the body of 
 
 1 m J 
 
 man: (i) ball and socket; (2) hinge. 
 
 CuT 
 
 HINGE JOINT OF THE 
 
 ELBOW 
 
ASSISTANCE FROM JOINTS 
 
 57 
 
 This completes the outline of the bony and muscular 
 machinery of our bodies. We have seen that the ends 
 of our bones are shaped to meet each other, that they 
 
 KNEE JOINT WHEN STRAIGHT 
 
 Notice the position of the knee pan 
 
 (After Schmidt) 
 
 KNEE JOINT BENT FAR OVER 
 
 Notice the ligaments that hold the 
 bones together 
 
 (After Schmidt) 
 
 are carefully fitted together, that tough ligaments hold 
 the one to the other, and that muscles end in tendons 
 which draw the bones in such directions as the joints 
 allow. 
 
CHAPTER VIII 
 
 THINGS THAT HINDER STRENGTH AND SPEED 
 
 Various public schools were in a state of high excite- 
 ment during the spring of 1905. The following item in 
 the New York Times shows the reason for it : 
 
 Schoolboy athletes are to hold their contests on the roofs of the 
 available public school buildings in the boroughs of Manhattan and 
 Brooklyn. . . . Each school is to enter five boys in each individual 
 event, and two teams in each relay race. Medals will be given to first, 
 second, and third in each event, and a trophy will be presented "to the 
 school scoring the most points. 
 
 Boys under thirteen, in these events, competed in the 
 potato race, the standing broad jump, and the relay race 
 for teams of four boys, each running twice across the roof. 
 Boys under fifteen had the same potato race, with running 
 higb jump instead of broad jump; and in the relay race 
 of four boys, each ran four times instead of twice across 
 the roof. Boys over fifteen did other things in addition. 
 
 Throughout the spring of that year, wherever New 
 York boys could find a roof large enough or a space of 
 ground unoccupied, there they went for fun, for exercise, 
 and for trophies. But the doctors of the city, the fathers, 
 the mothers, and the teachers believed most in the exercise. 
 
 58 
 
THINGS THAT HINDER STRENGTH AND SPEED 59 
 
 They were sure that through it city boys might gain 
 the greatest prize of all good health; and they were 
 more anxious to have the city turn hundreds of thou- 
 sands of boys and girls into healthy, well-developed, 
 long-lived men and women, than to have it turn out 
 a few wonderful athletes who should outrun and out- 
 jump all other boys in all other cities in America. 
 
 THE START AND THE FINISH OF THE HUNDRED-YARD RUN 
 
 The truth is that never before in the history of the 
 world has so much attention been paid to the health of 
 children as in this twentieth century; for, in the first 
 place, the laws of health are better understood to-day 
 than ever before, and further, the children themselves 
 are learning to judge what is best for the body. 
 
 Perhaps city children need this knowledge most, for, 
 in some ways, they have most to contend against. In 
 
60 THE BODY AT WORK 
 
 tens of thousands of cases real exercise for city children 
 is quite out of the question. City streets are too narrow ; 
 they are too full of cars and carriages, of men and women 
 and hurrying business of every sort. In such places 
 groups of running boys and girls are a nuisance, they 
 are impossible. And just because of this, athletic leagues 
 have been devised to help out the situation. The great 
 object of these leagues is to give wholesome exercise to 
 the bodies of such school children as are old enough to 
 take it. The way this is managed in New York City is 
 most businesslike : 
 
 1. The boys in each separate school of each of 
 the forty-six school districts are allowed to compete 
 with each other, and the best are chosen champions 
 of each school. 
 
 2. These champions compete with the other cham- 
 pions of the schools in the same district league, and 
 the successful school becomes champion of the dis- 
 trict. There is then a joyful celebration, to which 
 an officer of the city league comes. He not only 
 listens to the music and the speeches by the pupils, 
 but, at the proper moment, he too makes a speech 
 and presents to the school the trophy it has won. 
 Sometimes this trophy is a graceful silver cup, 
 eighteen inches high, bearing the date of the vic- 
 tory and the name of the school. Sometimes it 
 is a burnished bronze tablet to be hung on the 
 
THINGS THAT HINDER STRENGTH AND SPEED 6 1 
 
 school-room wall. In every case it is to stay with 
 the school for a year at least, and so long thereafter 
 as the school can continue to hold the champion- 
 ship of the district. 
 
 3. The champion school in each district league 
 competes with each of 
 the other league cham- 
 pions, and the victor 
 becomes the champion 
 school of the city. No 
 school in the league can 
 win a higher place than 
 this. 
 
 The beauty of these con- 
 tests is that, from the very 
 start, no boy feels that he 
 works for himself alone. In- 
 stead, each victory means 
 
 AN ALL-ROUND CHAMPIONSHIP 
 
 Victory for hlS School. Fellow- TRO p HY OF THE PUBLIC SCHOOLS 
 
 Students cheer him, for they ATHLETIC LEAGUE, NEW YORK 
 
 CITY 
 
 know and he knows that he 
 
 has won success for them as well as for himself. For 
 this reason each boy is most anxious to get the best pos- 
 sible service from his body, and many boys are shrewd 
 enough to make a special study of the laws of success 
 and failure. They are ready to do such things as help, 
 and to avoid such things as may hinder, their success. 
 
62 
 
 THE BODY AT WORK 
 
 This accounts for the self-denial which many of them 
 practice. They have learned that the best athletic train- 
 ers of college teams and of professional athletes through- 
 out the country strictly forbid their men to use tobacco 
 in any form. The boys also know that the reason for 
 this is the fact that tobacco so affects the heart as to 
 reduce a man's ability to do his best muscular work. 
 
 A HIGH JUMP AT NINE CONSECUTIVE MOMENTS 
 
 To do his best his heart must be in good condition 
 
 (After Schmidt) 
 
 Boys have learned from these same trainers that alco- 
 hol is strictly forbidden because it reduces the power 
 of the muscles. Being keen enough to see that that 
 which helps college students and professional athletes 
 is precisely what will help them, the most determined 
 of these boys give up their cigarettes and do not so 
 much as begin to use alcohol. Multitudes of other 
 boys are, of course, still smoking cigarettes, but in 
 
THINGS THAT HINDER STRENGTH AND SPEED 63 
 
 thousands of these cases ignorance explains their wil- 
 lingness to do it. 
 
 Any class or school that is interested in making 
 scientific investigations for itself might appoint a com- 
 mittee to look into the school records and into the run- 
 ning and jumping records of 
 their smoking and their non- 
 smoking classmates. Inves- 
 tigations of this kind must 
 be carried on for months, 
 or for a year if they are to 
 prove anything. 
 
 As a rule, at the end of 
 this time it will be found 
 that those boys who use the 
 most cigarettes are doing 
 the poorest work both in 
 the class room and on the 
 athletic field. The class or 
 the school that wishes to 
 make the best records will 
 therefore be forced to omit 
 from among its contestants all those who use cigarettes. 
 It will decide that it cannot afford to reduce its chance 
 for winning just because certain boys are either ignorant 
 about the laws of the body, or because they are already 
 victims of the cigarette habit. 
 
 MUSCLES TIGHTENED FOR THE JUMP 
 (After Schmidt) 
 
64 THE BODY AT WORK 
 
 Why did the American army have to refuse hun- 
 dreds of men who applied and who were ready to face 
 death for the sake of their country? In a large number 
 of cases it was because these men had a certain weak- 
 ness of the heart which was brought on by tobacco, and 
 because, when a man's heart is troubled in this particu- 
 lar way, he is not likely to be able to endure the exer- 
 cise which he will have to meet as a soldier. His heart 
 is not strong enough to risk it. 
 
 A HIGH JUMP FROM ONE FOOT 
 
 It shows the work done by different muscles from the moment the man 
 jumped until he stood on his feet again 
 
 (After Schmidt) 
 
 The same is true for athletes of every age and size in 
 whatever land they may be. He who is in the habit of 
 using cigarettes should be careful how he ventures to 
 do anything that will call for sudden, or violent, or vig- 
 orous use of his muscles and his heart. Although he 
 may still be able to run as fast and to jump as high as 
 his friend or his schoolmate who does not smoke, yet 
 the probability is that he has the sort of heart that the 
 American army often refuses to accept, the heart that 
 no soldier can afford to own. And the man who is 
 
THINGS THAT HINDER STRENGTH AND SPEED 65 
 
 afflicted in this way cannot expect to do his best on 
 the athletic field. 
 
 In this connection it is interesting to know what the 
 leading trainers of the country actually say about it. 
 
 Mr. Charles E.Courtney of the Cornell navy once wrote: 
 
 I have found in my experience that young men are much better off, 
 and do better work, without alcoholic stimulants than with them, and 
 they are, therefore, absolutely prohibited in our training. As to tobacco, 
 I believe young men do better work when not using tobacco than when 
 using it, and it is prohibited in our training here at Cornell University. 
 
 In 1900 Mr. Me Bride, captain of the Yale football 
 team, wrote : 
 
 It is absolutely necessary for a college or school athlete who is 
 striving to win a place on any team to have endurance ; especially is 
 this true in rowing and football. This can be accomplished to the 
 greatest degree only by abstaining from the use of tobacco and alco- 
 holic drinks while in training for said team. 
 
 In 1901 Mr. Edwards, captain of the Princeton 
 football team, wrote: 
 
 There is nothing which goes to make a better athlete, nothing 
 which gives a man greater power of endurance, than total abstinence 
 from the use of alcoholic drinks. . . . No one is expected to use tobacco. 
 A man who is using tobacco and alcohol contrary to orders during the 
 season is easily detected, and is dropped from the squad. 
 
 In 1906 Mr. A. A. Stagg of the University of Chicago 
 wrote : 
 
 We have never had a really successful long-distance runner at the 
 University of Chicago who was a smoker, and several of our men who 
 
66 THE BODY AT WORK 
 
 have been successful, like Lightbody, are most abstemious in their 
 training and do not smoke. The best sprinters and middle-distance 
 runners we have had have also been men who were very particular 
 about their training for several months of the year. ... In football, as 
 in other endurance tests, there is no question at all in my mind that 
 the man who smokes does not come up to the level of the general run 
 of nonsmokers. 
 
 In 1906 Mr. Gianini of the New York Athletic Club 
 wrote : 
 
 My opinion is expressed best by stating that I forbid the use of 
 tobacco in any form by men under my charge while training. 
 
 The Arctic traveler, Nansen, was asked by a neigh- 
 bor, " Did you take any alcohol with you when you left 
 the Fram to make your heroic expedition by sledges ? " 
 " No," said Nansen, " for if I had done so, I should never 
 have returned." 
 
CHAPTER IX 
 
 THE HEART WHEN IT IS AT WORK 
 
 Let some one hold a watch and be prepared to make 
 reports while you and perhaps your friends test your- 
 selves in various ways. 
 
 Stand with your finger 
 on your pulse at the wrist, 
 and let him who holds the 
 watch decide when the 
 counting is to begin. He 
 will say, "Get ready now 
 begin." When he says 
 that last word each child 
 should, for himself, start to 
 count the regular throb of 
 the pulse which he feels 
 under his finger. Let him 
 keep on counting until, at 
 
 the end of One minute, the COUNTING THE PULSE BEAT 
 
 timekeeper says, "Stop." You will then have your record. 
 
 If you are not excited, if you have not been exercising 
 
 hard beforehand, if you have made no mistake in your 
 
 counting, the number of beats which you feel will show 
 
 67 
 
68 
 
 THE BODY AT WORK 
 
 what your regular everyday pulse beat is. This is an im- 
 portant point gained. You have secured your standard for 
 the standing position. You are ready for the next test. 
 
 Stand perfectly still, and, while the timekeeper follows 
 the time again, open and shut your hand as fast and as 
 
 hard as you can for an entire 
 minute. Then once more count 
 your pulse. You may find that 
 it has gained a trifle. This will 
 depend on the vigor with which 
 you have worked the muscles of 
 your hand. In any case, how- 
 ever, the muscles there are small 
 and you will not get much of 
 a result in the way of a more 
 rapid beat. 
 
 Turn, therefore, to the leg 
 muscles of the body. Use them 
 HE COUNTS BOTH PULSE BEAT vigorously. Let each child run 
 
 AND HEART BEAT 
 
 up one flight of stairs and back, 
 
 and at once count the pulse again. You will find a 
 marked change. From eighty or over at the start, you 
 have probably increased the count by one half or more. 
 In addition to the above tests make one more. Even 
 while the fingers of your left hand are feeling the pulse 
 in your right wrist, place your right hand over your 
 heart. You will discover that the pulse beat and the 
 
THE HEART WHEN IT IS AT WORK 69 
 
 heart beat occur at the same instant. And now, if you 
 were not uncomfortably out of breath after the run up 
 one flight, try two flights for a second test and notice 
 that the number of beats has increased both at the wrist 
 and at the heart. You have proved for yourself that the 
 pulse beat may be depended on to show what the rate 
 of the heart beat is. 
 
 The following table shows what such exercise did for a 
 small class of children in a New York school. The letters 
 of the alphabet stand for the names of the children. 
 
 TESTS SHOWING EFFECTS OF EXERCISE ON THE 
 HEART BEAT PER MINUTE 
 
 Normal After Short, 
 
 Pulse Quick Run 
 
 A 85 130 
 
 Bo 83 142 
 
 C 71 U3 
 
 I> 85 95 
 
 E 85 113 
 
 F 88 120 
 
 G ........ 83 ....... 95 
 
 H . . . v 1 1 . . . 84 . . . . . . . 87 
 
 I ' . . 9O . . . . o . . 114 
 
 J ........ 98 ....... 130 
 
 K 85 ..,..., 94 
 
 L . . 85 . . o . . . . no 
 
 M 83 . . ' . . . . 104 
 
 N . . r 87 ..... .... . 115 
 
 Each child was tested again within a minute after the 
 run, and already the pulse was found to be beating more 
 
70 THE BODY AT WORK 
 
 slowly. This rapid return to the normal beat is the sign 
 of a healthy heart. 
 
 At different times, on different days, test yourself in 
 other ways. Count your pulse when you get up rested 
 in the morning and when you go to bed tired at night. 
 Count it before and after your cold bath in the morning. 
 Count it before and after any variety of exercise that in- 
 terests you. For example, run to school one morning, 
 walk to school another morning, and compare the results 
 of both with your standard. Compare the number of 
 beats of the heart that has done hard work with those 
 of the heart that has done light work, and learn to know 
 what gives your heart the most exercise. Knowledge in 
 this line will serve you well in deciding how to do the 
 most for yourself in the shortest space of time. What 
 you learn now will be applied in a later chapter. 
 
 It would be quite worth while to keep your different 
 records written down in a notebook of some sort for 
 future reference. Already, however, you have learned 
 that exercise makes the heart beat faster, and that the 
 larger the muscles are, and the harder the work you 
 give them to do, running, for example, the more 
 exercise will you give the heart. You have also learned 
 that the pulse may always be trusted to tell how the 
 heart is acting. 
 
 It is for this last reason that a doctor feels the pulse 
 of his patient. By the regular or the irregular beat of 
 
THE HEART WHEN IT IS AT WORK 71 
 
 that pulse, by the way it hurries and by the way it 
 drags, he is guided in his judgment as to what the con- 
 dition of the patient is, and what ought to be done to 
 help him. The heart, indeed, is one of the vital centers 
 of our activities. We are well or ill, we live or die, 
 through the work which it does or fails to do. Yet the 
 ignorant are often misled by its action. 
 
 I am acquainted with a frail woman who supposed for 
 years that she had heart trouble. She judged this by 
 the fact that her heart beat hard and fast when she went 
 upstairs, and that she lost breath easily when she went 
 for a walk. Since she had heart trouble, as she thought, 
 she decided that she must spare her heart as much as 
 possible, that she must do nothing that would set it 
 into vigorous action. At last she became so anxious that 
 she consulted a doctor, who assured her that her heart 
 was thoroughly sound. " It is weak, of course," he said, 
 "but how could it be otherwise? You say you have 
 been afraid to take any exercise for twenty years." 
 " Yes," she answered ; " I wished to be on the safe side." 
 He smiled in a queer way and said: "The safe side 
 would have been to give your heart a little energetic 
 exercise regularly. We need to train the heart just as 
 we train any other muscle of the body. The simple 
 trouble with your heart is that you have never given it 
 a chance to get strong." Being a sensible woman, my 
 friend began at once to follow the doctor's suggestion. 
 
THE BODY AT WORK 
 
 This, then, is one extreme to which a person may go. 
 On the other hand we have the bicycle rider who over- 
 taxes his heart so persistently as to injure it for life, and 
 the boys who run long or hard races before their hearts 
 
 have been trained for 
 such violent exercise. 
 
 It seems that the heart 
 is a strong, hollow muscle, 
 about as large as the fist 
 of the one for whom it 
 works; and that even 
 when it is not put under 
 extra pressure it does 
 more work than any 
 other muscle in the body. 
 It lies under the ribs, be- 
 tween the two halves of 
 the lungs, and keeps up 
 its beating from birth to 
 death. It does, indeed, 
 take more exercise than 
 any other muscle ; never- 
 theless, like every other muscle, additional exercise gives 
 it strength, while lack of additional exercise leaves it weak. 
 In training this important muscle we must remember 
 that most human beings have sound hearts that need to 
 be treated in a reasonable way. 
 
 THE HEART AND ITS GREAT 
 BLOOD VESSELS 
 
 We are well or ill, we live or die, by the 
 work it does or fails to do 
 
THE HEART WHEN IT IS AT WORK 
 
 73 
 
 A neighbor of ours had taken no special exercise all 
 winter, but when spring came he began abruptly by 
 playing one set of tennis after another, without resting 
 between the different sets. The end of it was that for 
 many days and nights his heart kept up a rapid beat- 
 ing. For three weeks, indeed, 
 it refused to come down to 
 normal, and during this time 
 the man dared take no exer- 
 cise. He knew it would be 
 unsafe. 
 
 If he had been careful 
 to begin his tennis playing 
 gradually that spring, in- 
 creasing the amount from 
 day to day, he would have 
 done better work, would 
 have spared his heart the 
 overstrain, and would have 
 saved himself those weeks of 
 time when he could take no vigorous exercise whatever. 
 
 Watch those who race to catch a train or car. By 
 the way they breathe you may know what the heart 
 is doing. You will also be able to tell which of the 
 running men and women have trained their hearts for 
 sudden sprints of violent work, and which are pressing 
 untrained hearts into unusual service. College students 
 
 THE CHAMPION PLAYER AT A 
 CRITICAL MOMENT 
 
74 THE BODY AT WORK 
 
 often run by the mile across the town and out into 
 the country. They are training not only the many 
 muscles of their legs, but also the one muscle of the 
 heart and their breathing apparatus. They wish to 
 train their leg muscles, while at the same time they 
 secure for themselves hearts and lungs that will be 
 useful as long as their legs are able to keep up the 
 running. 
 
 A doctor whom I know speaks of a man whom he 
 himself trained. He says: 
 
 When I took charge of him, the man could not run as far as from 
 here to the door without fainting. He simply had a muscularly weak 
 heart, excited by nervous shock and overwork, worry, deficient nutri- 
 tion, and lack of sleep. I first discovered that there was no organic 
 disease. Nothing but plain building up of muscle was needed. Then 
 I went to work and started to build up that muscle. I would have him 
 run a few steps and then lie down three minutes, then run a few steps 
 more and lie down. I stood by, keeping track of his heart, not allow- 
 ing him to do enough work to send it above one hundred and not letting 
 him run again until it got back to normal. I kept him at it half an 
 hour three times a day, from day to day increasing the doses ; that is, 
 I stuck to the medicine, but I gave very small doses, doses suited to 
 the strength of heart he then had. In three months that man could run 
 eight miles an hour with great ease and comfort. Since then he has 
 not known that he has a heart. 
 
 This doctor also speaks of a friend of his who ran up 
 eight flights of stairs because of a fire, and so over- 
 strained his heart that it has never been right since. 
 
THE HEART WHEN IT IS AT WORK 75 
 
 The point of all this is that when the heart has done 
 what it comfortably can, and then has to do still more 
 work and keep it up, it stretches too much for its own 
 good. And worse still, if it is stretched badly enough, 
 it stays stretched. This is part of the trouble with the 
 overworked heart of the bicycle rider. Athletic trainers 
 understand these facts thoroughly. It is therefore as 
 much for the sake of the muscle of the heart as for the 
 benefit of leg muscles that they insist that only those 
 who have been trained for the contests shall be allowed 
 to compete in athletic games. Otherwise the untrained 
 person might faint in the midst of the sport, and this is 
 not only harmful to himself but quite as unpleasant for 
 those who are watching the contest. 
 
 The safe rule is to give the heart all the exercise it 
 can comfortably take at one time, and to increase the 
 amount as fast as its power increases. 
 
 As a rule, the actual size of the normal heart is pro- 
 portioned to the work it has had to do. Animals kept in 
 cages and captivity have been examined after death and 
 their hearts have been seen to be smaller than the aver- 
 age heart of wild animals of the same species. In pro- 
 portion to its size, the heart of a stag is about twice as 
 large as that of a pig. The reason is plain. The stag 
 lives by exercise which makes the heart work ; the pig, 
 however, in his slow life, seldom indulges in any unusual 
 exercise. 
 
;6 THE BODY AT WORK 
 
 Provided the matter is not overdone, nothing is better 
 for heart development than exercise which calls for en- 
 durance. A quick run for a minute or a good jog trot 
 lasting five minutes are as good as anything that can be 
 devised. Run as you go to school in the morning; run 
 on the way home at night. At each time run a little, 
 then walk a little. Run only so much as you can 
 quickly recover from. Indulge when you can in a good 
 outdoor game. By your pulse beat and by the way you 
 keep your breath or lose it, you will know what you 
 may do. It is much better to begin with too little exer- 
 cise than with too much, for you are going to make 
 steady gain whatever your starting point is; and you 
 gain most by going moderately at first. 
 
 Throughout his entire life, he who has a well-devel- 
 oped heart will also have more vigor, more power to 
 endure, more courage than he otherwise would have. 
 
CHAPTER X 
 
 DISCOVERIES BY A GRECIAN AND AN ENGLISHMAN 
 
 Certain facts about the connection between the heart 
 beat and the pulse are so well known to-day that we are 
 in danger of forgetting the debt we owe to two great men, 
 Galen the Greek, and Harvey the Englishman. 
 
 Before Galen was born in the year 130 A.D., learned 
 men did indeed know that life stops when the heart 
 stops beating; they knew that the blood of the body 
 is contained in tubes; they saw that these tubes are 
 largest near the heart and that they divide and con- 
 tinue to divide until each muscle and organ of the body 
 is provided with its own unfailing blood supply. They 
 also studied the tubes themselves, and saw that they 
 are different enough to have two names. 
 
 Thus far in their investigations those ancients had 
 learned well. But now we stumble on their strange 
 error. " Veins," they said, " are filled with blood," a 
 correct statement. " But arteries," said they, " are filled 
 with air," an incorrect statement. The meaning of 
 the word " artery " itself proclaims their mistaken belief, 
 for in Greek it means nothing else thap air tube. 
 Although these ancient scientists made this mistake, 
 
 77 
 
78 THE BODY AT WORK 
 
 they described the structure of both veins and arteries 
 much as we see them to-day. In course of time they 
 even found, as we do, that the one great distinction of 
 the veins is that they are supplied with % numberless 
 pockets on the inside lining of each tube throughout 
 its entire length. 
 
 This was necessary, they said, because veins carried 
 blood ; whereas air tubes arteries needed no pockets, 
 because they were filled with a substance called u vital 
 spirits." 
 
 This belief of former scientists was perhaps not so 
 strange as it seems to us. The truth is, they were led 
 into error by the fact that after death the blood of the 
 body settles in the veins, not in the arteries. That is, 
 when a man is dead his veins are distended with blood, 
 while his arteries stand up firm and round but quite 
 empty. Those who investigated the subject came to 
 their conclusion, therefore, in the most natural way. 
 Then too, since the veins did certainly hold blood, they 
 saw no reason why, during life, another set of tubes 
 should also be filled with the same fluid. They did 
 not appreciate the difference between the two kinds 
 of blood which we know about. 
 
 But Galen the Greek was born. He practiced medi- 
 cine in Rome, and was so great a student of the human 
 body that, for fourteen hundred years afterwards, what 
 he had said and written about health, and medicine, and 
 
DISCOVERIES BY A GRECIAN AND AN ENGLISHMAN 79 
 
 the structure of the body of man was taught and be- 
 lieved in every school of medicine in Europe. He was 
 indeed the medical authority for the world. 
 
 Among other subjects he fastened his attention on 
 these same arteries and veins, testing them and exam- 
 ining them in different ways. The result was that, step 
 by step, he made progress. First he began to doubt 
 what he had been taught. Next he doubted absolutely. 
 But from doubt he moved on to a positive belief. When 
 this belief was firm in his own mind he declared pub- 
 licly that arteries as well as veins hold the blood of the 
 living body. 
 
 The scientific world was amazed. It disbelieved. It 
 said, " If you load up both sets of tubes with blood, 
 how are the vital spirits to get round ? " Galen replied 
 by proof and by argument. He talked and he wrote 
 until the other scientists of the time were as convinced 
 as he. They finally accepted his belief that there are 
 two kinds of blood: one kind in the veins, dark and 
 rich and thick, which was supposed to nourish the 
 heavier parts of the body; another in the arteries, light 
 and bright and red, well mixed with vital spirits, which 
 was supposed to do the lighter and the finer work for 
 muscle and tissue. 
 
 He believed that both kinds of blood were found 
 everywhere because both kinds were needed for the 
 special help which each could give. He also believed 
 
80 THE BODY AT WORK 
 
 that all this blood moved back and forth, here and 
 there, in haphazard fashion through the blood vessels, 
 that it shifted and drifted somewhat as the tides of 
 the ocean move hither and thither. 
 
 As for the connection between the heart and the 
 blood which we talk so much about, even Galen made 
 no discovery about this. He believed that the heart 
 expanded for the sake of drawing to itself breath from 
 the lungs to be mixed with the blood, and that it con- 
 tracted simply to get rid of such blood as it did not 
 need. 
 
 Much that Galen taught continued to be believed 
 until William Harvey made his great contribution to 
 the knowledge of the world. In 1616 we find him 
 lecturing in London. He was thirty-eight years old 
 at the time. But when he died, at the age of seventy- 
 nine, he had added such a volume of scientific facts to 
 those which Galen had discovered, that during these 
 three hundred years since then the two names have 
 stood side by side on the honored roll of those who 
 have transformed the beliefs of the human race. 
 
 Naturally, of course, Harvey began his work where 
 Galen and his successors left off. He built on foun- 
 dations which Galen had laid; but he was as inde- 
 pendent of past beliefs as Galen himself had been. 
 Whenever he had the opportunity, whether with men 
 or animals, whether with those that were well or ill, 
 
DISCOVERIES BY A GRECIAN AND AN ENGLISHMAN 8 1 
 
 alive or dead, he studied their bodies and gave special 
 attention to the action of the heart and to any connec- 
 tion which it might have with the blood supply. 
 
 In the case of wounded animals, at different times he 
 laid his hand on the heart and noticed that with each 
 throb the blood left the wound with a spurt, and he 
 saw that blood which spurted in jets from a wound was 
 always of the bright red kind. 
 
 Then too he came across wounds that bled in a dif- 
 ferent way. With them the blood simply poured out in 
 a quiet, dark-purplish stream. In such cases there was 
 no sudden increase of flow with the heart beat. He 
 found that the same was true for wounds in man and 
 beast alike ; that is, bright blood came in jets while dark 
 blood came in a quiet stream. Moreover, he saw that it 
 was always true that when the heart beat slowly the 
 pulse at the wrist was slow too. 
 
 These important observations, added to many experi- 
 ments which he himself made, drew Harvey's thoughts 
 more and more to questions about circulation. It then 
 occurred to him that the heart might be a special ma- 
 chine for pumping bright-colored blood out into the 
 arteries, and the thought of such a possibility was ex- 
 citing even to himself. 
 
 Through yet other experiments and constant thought 
 on the subject, his suspicions gradually changed to con- 
 victions. He became very sure that every pulse beat in 
 
82 THE BODY AT WORK 
 
 the artery at the wrist means that the heart has pumped 
 a fresh supply of blood into the large artery, the aorta, 
 which is joined directly to it, and that the elastic 
 tubes have expanded throughout their entire length to 
 make room for it. He knew, as we do, that the largest 
 arteries are buried deeper in the body than the veins, 
 and that only at certain spots do they come near 
 enough to the surface to allow us to feel the effect of 
 the heart beat. He noticed that there is never any 
 throb in a vein, and this strengthened his conviction 
 that no vein ever receives blood directly from the 
 throbbing heart. 
 
 By traveling the road which he took we have come 
 upon Harvey's first great discovery. I give it: 
 
 The heart pumps blood into the arteries. 
 
 The scientific world was even more excited over this 
 announcement than it had been over Galen's discovery. 
 But Harvey himself went quietly on with his investiga- 
 tions. He saw that the heart pumps by contracting and 
 expanding; that the average human body holds about 
 six quarts of blood; that the heart sends about half a 
 tumblerful of blood into the aorta every time it contracts ; 
 and that, since the heart beats about seventy times a 
 minute, an enormous quantity of blood must be squeezed 
 out of it during each half hour. 
 
 He did some multiplying, as we ourselves might do 
 just here, and decided that if the heart sends out over 
 
DISCOVERIES BY A GRECIAN AND AN ENGLISHMAN 83 
 
 one thousand tumblerfuls of blood every hour, and if 
 the body holds no more than twenty-four tumblerfuls, 
 that is, six quarts, the enormous supply must be ex- 
 plained somehow. Where did it all come from? This 
 was Harvey's next great problem. 
 
 One sign after another led him to suspect that the 
 veins might hold the explanation. He therefore tested 
 veins and arteries too, 
 as we ourselves may do. 
 
 Draw up your sleeve, 
 swing your arm round 
 your head once or twice, 
 let it hang by your side 
 for a minute, and you 
 will notice that some of 
 
 the blood Vessels appear A shows a vein slit lengthwise and laid open; 
 
 B shows a vein cut through lengthwise; 
 aS dark lines Under the c shows how a vein looks from the outside 
 
 skin. Stroke these lines when its valves are filled with blood 
 down towards the wrist. They are veins, and the little 
 bunches which stand out show where the valves have 
 caught the blood. Remember that these valves are on 
 the inside lining of every vein, and that they always 
 open towards the heart. During the time, then, that the 
 blood in the veins flows steadily towards the heart, the 
 valves lie flat and smooth against the lining and you 
 would not suspect their presence. But try to drive that 
 blood away from the heart, and quickly every valve is so 
 
 A B 
 
 POCKET VALVES IN THE VEINS 
 
8 4 
 
 THE BODY AT WORK 
 
 filled that it stands out like a little pouch and helps 
 block the passage of the blood backwards. The nature 
 of the veins, therefore, helped Harvey on towards his 
 next discovery. 
 
 While your left arm is still uncovered, press and 
 squeeze it with your right hand, stroking towards the 
 
 elbow to hasten the blood out of 
 the veins. Now, as quickly as you 
 can, tie a firm bandage about the 
 arm just above the elbow. Tie 
 this bandage as tight as you 
 can without giving yourself pain. 
 Within a few seconds notice how 
 you feel, and notice the color of 
 your hand. It remains pale and 
 it grows cold. 
 
 Arteries are buried deep, veins 
 are near the surface. Your band- 
 age is therefore checking the flow 
 
 A HANDKERCHIEF AND A STICK j n both gets Q blood vessds and 
 
 TO COMPRESS AN ARTERY 
 
 . ,, rt : u ." '. j n. u j because no blood can get into the 
 
 As the stick is turned the band- 
 age is pulled tighter arm, the color of it stays about 
 
 (After Tracy) as wnen you tied the bandage. 
 
 Above the elbow, however, you feel a throbbing, because 
 the blood in the arteries is held back by the dam of the 
 bandage. Loosen this bandage a little. You have now 
 lifted the pressure from the arteries, and blood hurries 
 
DISCOVERIES BY A GRECIAN AND AN ENGLISHMAN 85 
 
 towards the hand. But the veins are under pressure still ; 
 notice what is happening. Blood is entering through the 
 arteries ; it cannot escape through the veins because of 
 the pressure of the bandage. As a result the hand grows 
 red and swollen from its unusual supply. Release the 
 bandage entirely, and in al- 
 most no time those veins have 
 relieved themselves. Blood is 
 once more streaming upwards. 
 
 Such experiments as these 
 and others led Harvey to his 
 second announcement. He 
 declared to his astonished 
 friends that: 
 
 The heart receives its entire 
 blood supply from the veins. 
 
 To complete this account, 
 
 , , . , A, vein that brings blood to the auricle; 
 
 turn to the heart again and ^ auric ie ; c, valves that are forced 
 remember the following facts P en b y the blood as k P asses into 
 
 the ventricle ; Z>, ventricle ; , tube 
 about it '. through which blood goes to the lungs 
 
 1. The heart is a pow- to be purified 
 
 erful muscle. It does its work by contracting and 
 relaxing. 
 
 2. The heart is made up of two halves; and 
 the wall of muscle between these separate halves 
 is so firmly closed that after birth, and after the 
 heart is in good working order, not a drop of 
 
 THE RIGHT AURICLE AND 
 VENTRICLE 
 
86 
 
 THE BODY AT WORK 
 
 blood ever passes through it from one side to 
 the other. 
 
 3. Each half of the heart has two divisions, the 
 smaller called the auricle, the larger called the 
 ventricle. 
 
 TWO VIEWS OF THE SAME VENTRICLE TO SHOW THE VALVES 
 
 On the left biood enters ; on the right the ventricle contracts 
 and forces the blood onward 
 
 4. Each auricle and each ventricle has its own 
 opening, is own tube for blood, and its own valves 
 to prevent the blood from running the wrong way. 
 
 5. The auricle in each half of the heart always re- 
 ceives the blood and sends it into its own ventricle. 
 
 6. Each ventricle receives blood from its own 
 auricle and ends it off to its own district of^the 
 body. 
 
 At this point we reach a most interesting fact about 
 this process of circulation; yet it may be given in a few 
 
D 
 
 DISCOVERIES BY A GRECIAN AND AN ENGLISHMAN 87 
 
 easy words. One side of the heart receives blood from 
 
 the body and sends it to the lungs ; the other side of the 
 
 heart receives blood from 
 
 the lungs and sends it to the 
 
 body. We see, then, that one 
 
 side always deals with pure 
 
 blood alone, for all that comes 
 
 to it is fresh from the lungs 
 
 and is sent onward in the same 
 
 condition; while the other side 
 
 deals with impure blood alone, 
 
 for all that comes to it is 
 
 from the body after it has been 
 
 used, and it goes onward to 
 
 the lungs in that condition to 
 
 be purified. 
 
 Thus the entire blood 
 supply of the body, on each 
 journey round, passes through 
 both sides of the heart and 
 through the lungs before it 
 goes back to nourish the body. 
 This was Harvey's great dis- 
 covery about the circulation of the blood. Even for 
 him, however, there was a mystery which the microscope 
 alone could solve. The next chapter will speak about it. 
 
 THE FOUR CAVITIES OF THE 
 HEART 
 
 A, auricle ; B, ventricle ; C, outline 
 of the heart; D,D, blood vessels 
 
 The dark side receives impure blood 
 from the body and sends it to the 
 lungs ; the light side receives pure 
 blood from the lungs and sends it 
 to the body 
 
CHAPTER XI 
 
 TO THE CAPILLARIES AND BACK 
 
 To complete the proof about blood which makes its 
 regular journey from the heart round the body and back 
 again, scientists have the testimony of the blood itself. 
 They have taken a syringe as slender as a needle, and by 
 its use have pricked some harmless chemical into a vein 
 on one side of the body of a horse or of a man. They 
 have then examined blood drop by drop from the cor- 
 responding vein on the opposite side of the body until 
 the same chemical has appeared there. 
 
 By comparing the time when the substance was put 
 in, with the time when they find it again, they know how 
 long it takes for blood to make the entire circuit of the 
 body. The following table gives results : 
 
 For a horse, twenty-five seconds. 
 For a full-grown man, twenty- three seconds. 
 For a child of fourteen, eighteen seconds. 
 For a child of three, fifteen seconds. 
 
 Evidently each set of tubes and each heart does its 
 work more or less rapidly, according to the distance 
 which the blood has to travel. But for each one of us 
 the road which the blood takes is ever the same. The 
 
 88 
 
VEINS AND ARTERIES 
 
 Black tubes represent veins through which impure blood goes to the right side 
 
 of the heart from all parts of the body ; light-colored tubes represent arteries 
 
 through which pure blood from the left side of the heart goes to all parts of 
 
 the body. Notice that the large tubes of each kind lie near one another 
 
 89 
 
THE BODY AT WORK 
 
 steps of its progress are veins, heart, lungs, heart, arteries, 
 veins. When the chemical is found it is on its return 
 trip to the heart. 
 
 Even this experiment does not, however, show how 
 the blood gets across from the arteries to the veins 
 
 for its journey back. 
 Harvey himself was 
 not sure about this, 
 for he had no micro- 
 scope. But when the 
 microscope came with 
 its revelations, doubts 
 and questions were 
 cleared away. Instead 
 of blood spread about 
 everywhere among 
 the muscles under the 
 skin between the ar- 
 teries and the veins, 
 there was found to be 
 no blood anywhere 
 outside of the tubes. Moreover, each drop of blood was 
 found to be a part of the ceaseless stream which flows 
 through tubes that divide and subdivide until they are 
 too small for the unaided eye to see, then unite and 
 continue to unite until they are again large enough to 
 be seen. 
 
 UNION OF ARTERIES AND VEINS 
 
 rt, artery; z>, vein. A network of capillaries 
 joins them 
 
TO THE CAPILLARIES AND BACK 91 
 
 From the heart and back again, all the blood of the 
 body is seen to be closely inclosed in these larger and 
 smaller tubes. This is what the microscope shows. And 
 the sight of its progress through the tubes must have 
 thrilled those who watched it for the first time. 
 
 One early scientist used his crude microscope on the 
 tail of a tadpole. He had already discovered the corpus- 
 cles of the blood, which we shall study soon; and he 
 saw these separate " blood globules," as he called them, 
 moving after each other in single file through the nar- 
 rowest of the tubes. Sometimes they moved in faster, 
 sometimes in slower, procession; and sometimes they 
 were even bent over and pressed out of shape as they 
 were forced through the narrowest places. He grew 
 enthusiastic over what he saw, and wrote a glowing 
 account of it over two hundred years ago: 
 
 The motion of the blood in these tadpoles exceeds all the rest of 
 small animals and fish I have ever seen ; nay this pleasure has ofttimes 
 been so recreating to me that I do not believe that all the pleasures of 
 fountains and waterworks, either natural or made by art, could have 
 pleased my sight so well. And now at last I spied a small artery, that 
 notwithstanding it is so small that, I judge, but one small red globule 
 of blood could pass through it, ... yet, what was most remarkable 
 was to see the manifold small arteries that came forth from the great 
 one, and which were spread into several branches, and turning, came 
 into one again, and were reunited, that at last they did pour out the 
 blood again into the great vein ; this last was a sight that would amaze 
 any eye that was greedy of knowledge. 
 
THE BODY AT WORK 
 
 From what he saw, and from what the microscope 
 may show us, too, we find it easy to understand that 
 every slash and wound of the body cuts through a mesh 
 of lace work more delicate than the finest lace ever made 
 by the hand of man ; we see that each thread of this lace 
 is a tube doing faithful duty in carrying blood to remote 
 regions of the body, and that everywhere there is blood 
 simply because everywhere there is the same intricate 
 
 interlacing of these marvelous 
 tubes. Their name capillary 
 means " hairlike." Yet the mi- 
 croscope shows how much 
 smaller they sometimes are 
 than any human hair, however 
 soft and fine. 
 
 By careful calculation it has 
 been found that fifteen hun- 
 dred capillaries would have to be laid side by side to 
 cover a surface an inch wide. 
 
 As a rule, the amount of blood which is inclosed in 
 this system of tubes which includes heart, arteries, capil- 
 laries, and veins, is about one thirteenth the weight of 
 the person. We may then calculate our own supply of 
 blood by our own weight. 
 
 So much blood does it take to keep the blood vessels 
 and the heart as full as they need to be. The truth, 
 however, is that being elastic they could at any time 
 
 CORPUSCLES IN THE CAPILLARIES 
 OF A FROG'S FOOT 
 
THE HEART WITH ITS SYSTEM OF TUBES 
 
 Arrows show the direction in which the blood flows. Follow its course from the 
 
 body into the right side of the heart ; from there to the lungs ; thence to the left 
 
 side of the heart and out to the body again. Each cluster of tubes shows in a 
 
 rough way where some organ of the body is located 
 
 93 
 
94 THE BODY AT WORK 
 
 hold more than is now in them ; and that at any time 
 also they could get along very well with rather less than 
 they now carry. 
 
 In former times men sometimes died for no other rea- 
 son than that they lost so much blood from wounds of 
 one sort or another that the sides of veins and capil- 
 laries collapsed, and the heart had to stop work because 
 there was too little blood left in the body to be pumped 
 round. It was therefore a great discovery when men 
 found that the heart is quite as willing to pump warm 
 salt water out into arteries and capillaries as to send 
 warm blood to the same places. Nowadays, therefore, 
 when a man is losing much blood through an operation 
 or through an accidental wound, a surgeon, working as 
 fast as he can, pumps salt water into the veins to replace 
 the blood. This water is carried on round the circuit as 
 swiftly as if it were the richest blood, the pumping of the 
 heart continues, and a life is saved. 
 
 No one dreams for a moment that salt water can take 
 the place of blood day in and day out for many days 
 continuously, but all know that it may be depended on 
 for a season. It keeps the veins filled and the heart in 
 action while the proper sort of blood is being manufac- 
 tured by the body itself. 
 
 In a way we might suppose that, whether water is 
 mixed with it or not, the blood of the body is spread out 
 in equal quantities everywhere, being regulated by the 
 
TO THE CAPILLARIES AND BACK 95 
 
 size of the tubes which carry it here and there. The 
 truth is, however, that standing over the blood supply is 
 the never-failing fact that exercise regulates the amount 
 which goes here and there; that is, what we do always 
 settles the question as to where the blood shall go. For 
 the normal, healthy person this law never varies. It 
 may be stated in a few words : That part of the body 
 which is exercised the most gets the most blood ; that part 
 which is exercised the least gets the least blood. 
 
 The next chapter will show what it means to the body 
 when this law is remembered or forgotten, and what the 
 nature of the blood is, that it should be so greatly needed 
 here and there. 
 
CHAPTER XII 
 
 BLOOD INSIDE AND OUTSIDE THE TUBES 
 
 When you take your morning bath why do you use 
 cold water, a rough wash cloth, and a towel rougher yet ? 
 Why do you work fast and rub hard? For the simple 
 reason that you wish to draw more blood to your skin 
 capillaries, and the pink color shows how well you have 
 succeeded. 
 
 I have a frail friend with blood vessels so lifeless that 
 her skin is about as pale after exercise as before it. The 
 other day, however, she felt encouraged. "An unusual 
 thing happened this morning, " she said ; " I managed to 
 get some color into my chest when I rubbed it. I have n't 
 been able to do that before for years. " She knew that 
 active movement of the blood through the blood vessels 
 is one of the important advantages of exercise. To under- 
 stand this more definitely, examine the blood itself. Drops 
 drawn from your own body will meet the need perfectly. 
 To secure them, tie a string round the last joint of a fin- 
 ger on your left hand. This leaves your right hand free 
 for whatever it needs to do. Bend the tied finger over 
 to increase the pressure of the blood in its capillaries. 
 
 Take the finest needle you have, hold it in a candle or a 
 
 9 6 
 
BLOOD INSIDE AND OUTSIDE THE TUBES 
 
 97 
 
 lamp flame for a moment to rid it of microbes, then stick 
 the point of it quickly into the dark red end of the finger. 
 So much blood has been held back that you will barely 
 feel the prick. Nevertheless, a good-sized drop will ooze 
 through and be ready for immediate use. 
 
 To get this blood you have torn open the sides of sev- 
 eral capillaries smaller than the needle ; but they will 
 repair themselves in time, 
 and just at present you 
 have more need of that red 
 drop outside of your body 
 than inside of it. Have a 
 piece of clean glass ready 
 and jostle the drop of blood 
 down upon it. Raise the 
 glass, hold it over some- 
 thing white, and notice the 
 color. You will see that it 
 has a yellow tinge. 
 
 Now break through a 
 few more capillaries with your needle ; draw another drop 
 of blood ; put it also on the glass, and leave it there for 
 five or six minutes. Look at it now and you will find that 
 it has turned itself into jelly. Set a tumbler over it and 
 let it remain there undisturbed for half an hour or so. At 
 the end of that time you will see a bit of red substance 
 floating in a small drop of liquid which is almost colorless. 
 
 PREPARED TO DRAW A DROP OF BLOOD 
 
 OF THE 
 
 UNIVERSITY 
 
9 8 
 
 THE BODY AT WORK 
 
 Look back at the finger you pricked, and, if you did 
 not wipe it off clean after you pricked it last, you will see 
 that there, too, a remnant of the blood has hardened round 
 the edges of the tiny wound. This will remind you of the 
 statement so often made, that the best healer for a wound 
 
 is the blood which oozes 
 through it. We clean a 
 wound thoroughly, we pull 
 * ne edges towards each 
 other, we even sew them 
 together sometimes, and 
 the blood which continues 
 to ooze from the capillaries 
 hardens on the edges of 
 the wound. We are care- 
 
 ful to leave it there undis- 
 turbed, for we know that 
 
 A few red ones are highly magnified. Those it cloSCS the break better 
 that are less magnified show how corpuscles , 1 * J -f 1 
 
 stick together after blood is drawn from the than any Kind OI plaster, 
 body. Two white corpuscles are given an( j t ^ at t | ie WO 7] C o f knit- 
 ting these separated edges together goes on best under 
 the crust of hardening blood. 
 
 If we could add the use of a good microscope to our 
 experiments, and if we knew just how to use it for 
 such close investigations, we should draw a third drop of 
 blood, put it under the microscope, and learn a number 
 of startling facts about its composition. We should then 
 
 CORPUSCLES SEEN BY THE AID OF A 
 MICROSCOPE 
 
BLOOD INSIDE AND OUTSIDE THE TUBES 99 
 
 recognize it as a liquid with multitudes of small red and 
 white objects floating in it. Blood is indeed a mixture 
 of three things: 
 
 i. Red objects called red corpuscles. There are 
 
 something like two hundred million of these in each 
 
 drop of healthy blood. Imagine then their size ! 
 
 Each is round and flat 
 
 and has a concave cen- 
 ter. Its shape is such 
 
 as you would get by 
 
 taking a wax marble l 
 
 and mashing it between 
 
 the thumb and finger. 
 
 Pressed in this way, 
 
 the center is thinner 
 
 than the edges. So is 3" 4 
 
 it with every red COr- RED AND WHITE CORPUSCLES 
 
 Nevertheless, Four different shapes and four positions 
 
 .... taken by the same white corpuscle 
 
 these microscopic disks 
 
 are the important oxygen carriers of the body, and 
 they never leave the blood tubes unless these tubes 
 themselves are crushed or cut or forced to leak 
 through accident or disease. 
 
 2. The liquid part called plasma. This is quite 
 transparent and almost colorless. A little over one 
 half of each quart of blood is plasma; the rest is 
 the corpuscles. 
 
100 THE BODY AT WORK 
 
 3. Colorless objects called white corpuscles. Of 
 these there are only about six hundred thousand 
 to each drop of blood, although the number varies 
 greatly from time to time. They are specks of jelly- 
 like substance that change their shape constantly. 
 They not only travel with the other corpuscles in 
 the plasma, but they also work their way through the 
 walls of the capillaries and wander here and there 
 in the body. They destroy intruding microbes when 
 they find them, and help more than any other part 
 of the blood in healing a wound. Much more is 
 told about these white corpuscles in the thirteenth 
 chapter of Control of Body and Mind. 
 Plasma, red corpuscles, and white corpuscles tell us all 
 that the microscope shows when we use it for the study 
 of blood. But a chemist will take the same blood, will 
 analyze it in his laboratory, and will prove that it is made 
 up of many different substances of which we have not so 
 much as heard the names, substances needed, however, 
 for the work which each separate part of the body is 
 doing. He will tell us that within this blood is all that 
 is needed for the manufacture of bone and muscle, hair 
 and tendon, tears and fat and finger nails ; that it is the 
 source of supply for all that lies under the cover of the 
 skin, the storehouse for more treasures than we have 
 even dreamed about ; and that it is easy to enrich or to 
 impoverish the blood by our treatment of the body. 
 
BLOOD INSIDE AND OUTSIDE THE TUBES ioi 
 
 This then is the blood itself, the surprising red liquid 
 which some of us are so afraid to touch, the marvelous 
 red liquid which determines our health for us. While 
 it moves through our branching blood vessels we live ; 
 when it stops moving we die; and in proportion as it 
 is well supplied or unsupplied with that which each part 
 of the body calls for, are we well or ill. It is this last 
 fact indeed which should make the study of these pages 
 of priceless value to us, for through the knowledge 
 which we gain of physiology and hygiene we shall 
 finally learn how to keep the body supplied with the 
 kind of blood which it must have in order to do its 
 best work for us. 
 
CHAPTER XIII 
 
 EXCHANGES ALONG THE TUBES 
 
 Even a careless thinker will see that however intricate 
 the lace work of capillaries is, and however closely these 
 
 small tubes are intertwined with 
 tissues of muscle and gland, still 
 the blood within the tubes is use- 
 less to the body unless it can be 
 brought into direct contact with 
 the muscle and gland tissues 
 themselves. 
 
 An experiment will make the 
 situation plain and will show what 
 
 The smaller glass holds fresh 
 
 water, the larger holds water the OUtCOme of it is. 
 
 Get from the butcher a piece of 
 
 fresh animal membrane, the bladder will do. Fill a 
 small glass with fresh water, tie the membrane tightly 
 over it, set the glass into a much larger one filled with 
 salted water, letting the water cover it, and leave the 
 two tumblers together over night. In the morning take 
 the smaller from the larger, unfasten the membrane, and 
 taste the water which was fresh and sweet the night be- 
 fore. You will find that it is now distinctly salt. Taste 
 
 ONE GLASS WITHIN THE 
 OTHER 
 
 102 
 
EXCHANGES ALONG THE TUBES 103 
 
 the water in the larger tumbler. You will find that it 
 has grown fresher than when you left it. 
 
 In this exchange the salt in the liquid has acted 
 according to a universal law. Salt is indeed one of the 
 many substances which always pass easily back and 
 forth through any moist animal membrane. 
 
 Put sugar into one liquid and soda into another; let 
 a membrane be stretched between them, and before long 
 you will have two liquids that have become strangely 
 alike. The different substances in the liquids have 
 changed places through the membrane. 
 
 Even gases are subject to the same law. Men who 
 know how to handle such things can put oxygen in one 
 tube and carbon dioxid in another. They can then ar- 
 range to separate the gases by a piece of animal mem- 
 brane stretched between the tubes, and they discover that 
 the two gases refuse to stay apart. Indeed, so much of 
 each finds its way through the partition that soon there 
 is a mixture of the two on either side of the membrane. 
 
 Experiments such as these answer the query as to 
 how the body gets what it needs from the blood. 
 Everywhere it is the animal membrane of the tubes 
 themselves which separates the blood within the tubes 
 from a certain other liquid which lies close about them 
 on the outside. 
 
 However small and however thin walled the blood 
 vessels may be, there is always this lymph bathing the 
 
104 THE BODY AT WORK 
 
 outside like a sort of colorless sap in the body, and mak- 
 ing its exchanges with the contents of the liquid within 
 the capillaries. Moreover, this lymph which soaks slowly 
 but constantly through every tissue of the body is laden 
 with carbon dioxid which it has received from the tis- 
 sues of the body. The blood is rich in oxygen, and it is 
 separated from the lymph only by the walls of the cap- 
 illaries. In view of this, what could be more natural 
 than the thing which comes to pass? These gases in 
 the lymph and in the blood change places with each 
 other as promptly as do the liquid materials which are 
 also in the lymph and in the blood. 
 
 It is evident, then, that the lymph is as important to us 
 as is the blood itself. In fact, the two must always travel 
 side by side. They are indispensable to each other. 
 Without the one the other is useless. Three statements 
 will show how close the relation is : 
 
 1. Blood in the arteries is the result of the food 
 we eat and of the air we breathe. It contains every 
 supply that any part of the body needs for nourish- 
 ment, for strength, and for growth. 
 
 2. Blood in the veins is what is left after the lymph 
 has taken from it the oxygen and other nourishment 
 which the body needs, and given in exchange the 
 carbon dioxid and other waste which must be carried 
 off. In other words, venous blood is rich in waste from 
 the tissues and poor in nourishment for the tissues. 
 
EXCHANGES ALONG THE TUBES 105 
 
 3. Lymph is made up of rich, nourishing plasma 
 from the blood, on its way to the tissues, and of 
 waste material from the body, which will soon pass 
 into the capillaries, be carried onward in the veins, 
 and be disposed of as we shall learn hereafter. 
 Lymph is also the highroad to the blood for many 
 substances that are being manufactured by the dif- 
 ferent organs of the body. These manufactured 
 articles must find their way into the blood, for only 
 through circulation will they ever be able to reach 
 their destination. 
 
 The origin of the lymphatic tubes is strangely inter- 
 esting for the simple reason that it is so very indefinite. 
 Each seems to begin about as irregularly as a stream 
 gathers water in a swamp. 
 
 As we know, blood vessels are a closed system of tubes 
 with a stream of blood sweeping through them endlessly, 
 going ever round and round, from heart back to heart 
 again. In this great system not even the smallest tube 
 in the remotest region of the body is left with an open 
 mouth. The lymphatic system, however, works on quite a 
 different basis. Here the vast multitudes of the smallest 
 tubes seem to be really little more than open mouths into 
 which liquid is gradually making its way. Bear this in 
 mind while the facts are given as definite statements : 
 
 i . Each blood vessel of the body makes its way 
 through a mesh work of tissues. 
 
106 THE BODY AT WORK 
 
 2. Everywhere among these intertwined tissues 
 there is a colorless liquid called lymph. The capil- 
 laries of the blood are surrounded by this lymph 
 even as grass and weeds are surrounded by water 
 in a swamp. Lymph looks like plasma of the blood. 
 
 L 
 
 A CLUSTER OF TUBES 
 
 Look for those with open mouths : A, artery ; V, vein ; 
 Z, Z, Z, lymphatics 
 
 3. Lymph and plasma are constantly making 
 exchanges through the walls of the tubes of the 
 blood vessels. * 
 
 4. Plasma receives from the lymph all that the 
 body is through with all that should go on in 
 the blood and be disposed of elsewhere. 
 
EXCHANGES ALONG THE TUBES 
 
 107 
 
 5. Lymph receives from the plasma all the nour- 
 ishment which the tissues need. 
 
 6. Opening away from the loose fibers through 
 which the blood vessels run, and in which all this 
 exchange is going on, 
 
 there are other tubes 
 about as small as the 
 capillaries; and into the 
 open mouths of these 
 tubes the lymph from the 
 tissues gradually makes 
 its way. 
 
 7. Vigorous exercise 
 hastens the flow of lymph 
 no less than of blood, and 
 the tissues are benefited 
 thereby. 
 
 8. From start to finish 
 the lymphatic tubes pro- 
 gress from Smaller to LYMPHATICS OF THE HAND 
 
 larger, as do those of the 
 veins. They are also pro- 
 vided with inside pockets quite like those of the 
 veins. These pocket valves keep the lymph from 
 moving backwards and help to send it constantly 
 onward, that it may at last mingle with the great 
 stream of blood that goes to the heart. 
 
 Smaller tubes lie near the surface, 
 larger ones lie deeper 
 
io8 
 
 THE BODY AT WORK 
 
 9. This progress from smaller to larger tubes con- 
 tinues until all the lymph of the body finds its way 
 
 through two large lymph 
 tubes, one on each side of 
 the neck. These empty 
 into two large veins, and 
 thenceforward lymph and 
 blood go on their way to- 
 gether to the heart. The 
 lymph, with all it has gath- 
 ered, has now entered the 
 circulatory system, and thus 
 the contribution from the 
 many different organs of 
 the body will be distributed 
 by means of the blood. 
 The movement of this 
 fluid continues during life, 
 for the lymph vessels and 
 lymph spaces can never 
 be empty so long as the 
 
 The lymph tubes are white and are Organs of the body are at 
 seen to empty into the large veins W Qj-lr 
 
 A special point to remember is that blood vessels and 
 the tissues are as much better off when fresh lymph sur- 
 rounds them, as are fish when they are in fresh water. 
 
 VEINS AND LYMPH TUBES 
 
CHAPTER XIV 
 ALCOHOL AND CIRCULATION 
 
 A man is sometimes so sensitive about the dull red 
 end of his nose that he is ready to welcome almost any 
 device which may rid him of it. Perhaps he knows and 
 
 PRICKING THE CAPILLARIES 
 
 By electricity through the point of a needle many capillaries are 
 destroyed ; after that the man is cured of his red nose 
 
 (Copied from the Literary Digest} 
 
 perhaps he does not know that the reason for the color 
 is the condition of his capillaries. Each smallest tube in 
 
 the special spot is indeed overcharged with blood ; and 
 
 109 
 
1 10 THE BODY AT WORK 
 
 in so far as a nose is bright red or dull red are we our- 
 selves able to judge as to whether or not the capillaries 
 are particularly distended just there. 
 
 Red eyelids and a pink nose tell plain facts about the 
 state of the capillaries in those particular regions. But in 
 the matter of general health, the mere fact that a man has 
 a red nose signifies very little. Many a hearty sea captain 
 has carried such a nose with him through half a century 
 of life. He has lived to be eighty years old or older, and 
 the shade of his sunburned nose has made him neither 
 more nor less healthy than he otherwise would have been. 
 
 Sometimes, however, the color of a man's nose is a 
 sign of general internal conditions. It may show that 
 the capillaries throughout his body are loaded with 
 slow-moving blood ; and this condition of the capilla- 
 ries throws a flood of light on the sort of work which 
 the heart itself is doing. 
 
 Judging by facts which we have already learned, three 
 points are clear: 
 
 1. Slow-moving blood is more impure than that 
 which moves faster; for this reason such blood is 
 always a disadvantage to any part of the body in 
 which it tarries. 
 
 2. The mere fact that blood is moving fast shows 
 that impurities are being hastened out of the way 
 and that fresh material is being supplied to lymph 
 and tissue. 
 
ALCOHOL AND CIRCULATION 1 1 1 
 
 3. The blood vessels must always be in a healthy, 
 vigorous, elastic condition if the best exchanges are 
 to be made through their walls. 
 
 In view of these statements we are ready to under- 
 stand a set of scientific discoveries about circulation 
 which have been made during the past few years. It 
 appears that for many previous years educated doctors 
 and ignorant men alike were united in the conviction 
 that alcohol was a genuine help to the vigor of the cir- 
 culation. Thousands of men thought they had proved 
 this by personal experience. At different times, and in 
 different places, they had taken alcohol in large doses 
 or in small doses as they chose, and after the drinking 
 they had tested their hearts and knew by the count of 
 the pulse that the number of heart beats had increased. 
 They felt the blood bounding faster through their veins, 
 and it was most natural for them to believe that the 
 alcohol which they had taken had strengthened the 
 heart, even as food strengthens the body. 
 
 In time, however, an instrument was invented which 
 measured the strength of each heart beat. This -instru- 
 ment is in wide use to-day, because doctors find that 
 they can judge in a general way as to whether a man is 
 well or not by the vigor or the languor with which his 
 heart does its work. 
 
 And now for the surprise which overtook doctors 
 and scientists alike. They took alcohol themselves ; 
 
1 1 2 THE BODY AT WORK 
 
 they gave it to their friends and their patients; they 
 studied the heart and found that its throbs had in- 
 creased in number. But when they also used the in- 
 strument the sphygmograph they were surprised to 
 see that the heart was not putting as much power into 
 each stroke now as it did before the alcohol was taken. 
 
 THE SPHYGMOGRAPH IN PLACE 
 
 By the use of this instrument men determine the strength of 
 the heart beat 
 
 Over and over again the tests were made, and always 
 with the same result. Each trial showed that although 
 the heart was now pumping faster than usual, it was 
 nevertheless doing its work with less vigor. It was 
 using less force for the increased number of strokes 
 than it used for the smaller number made before alco- 
 hol had been added to the blood. 
 
 Testimony of this sort put a new color on the practice 
 of using alcohol when the heart needs to be strengthened. 
 
ALCOHOL AND CIRCULATION 113 
 
 Doctors in every land had to yield to the evidence of 
 their senses. They had to believe that, instead of giving 
 strength, alcohol actually robs the heart of a part of the 
 strength which it had before the alcohol was taken. 
 
 This was a difficult doctrine to accept, and question 
 and investigation continued to pursue each other in 
 quick succession until at last there was no further 
 doubt about it. To-day the facts of the case are ac- 
 cepted by all persons except those who are not up to 
 date in the matter. I give a few of the most important 
 points : 
 
 1. Healthy tubes that carry blood are elastic. 
 They stretch out when blood is pumped into them 
 by the heart, and they contract firmly again as they 
 send the blood onward. 
 
 2. The first effect of alcohol in the body is to 
 paralyze in a very slight way every tube that has 
 anything to do with carrying blood hither and 
 thither. 
 
 3. Because the tubes are slightly paralyzed they 
 are more relaxed than formerly. They contract less. 
 They therefore offer less resistance to the blood that 
 is pumped into them. After they are full they stay 
 relaxed, and do not have the elastic power to pull 
 themselves firmly into shape again. 
 
 4. The heart is also slightly paralyzed by the 
 alcohol. Still those countless relaxed tubes offer so 
 
1 14 THE BODY AT WORK 
 
 little resistance that the heart pumps the blood into 
 them with less effort than formerly, and, as a result, 
 contracts more frequently. 
 
 Thus far, however, no harm appears. The capillaries 
 are full of blood; the man feels the warmer for it, and 
 his heart is beating a trifle faster than usual. That is all. 
 But now begins the chapter of damages and calamities. 
 
 During the time that the heart itself is weakened, it can- 
 not put force enough into each stroke to drive the blood 
 on in spite of the relaxed state of the walls of the tubes. 
 Various results are now inevitable. Blood moves more 
 slowly through the tubes; it is slow in carrying away 
 broken-down tissue from the lymph ; it is slow in bring- 
 ing fresh nourishment for the rebuilding of the tissues. 
 
 In the meantime, if alcohol continues to be taken, the 
 capillaries may be kept stretched so long as to lose all 
 power to contract. If this is persisted in, the walls them- 
 selves end by becoming thicker and stiffer. The work of 
 exchange which should go on at a rapid pace through 
 them is thus interfered with, and the health of the 
 drinker suffers in numerous ways. 
 
 This is no fancy picture. It is simply the history of 
 circulation in such persons as are ignorant enough to 
 be willing to rob themselves of the work which their 
 blood and their blood vessels should do for them. 
 
 The most alarming side of the affair, however, is in 
 connection with what happens to the heart. Because 
 
ALCOHOL AND CIRCULATION 115 
 
 this tireless pump is weaker than it was, it also becomes 
 stretched ; and as it cannot do full work, it lacks the 
 exercise which would keep it in vigorous health. It 
 grows flabby, as does an unused arm. Fat gathers be- 
 tween its fibers, even as fat gathers in other muscles 
 when they do less work than usual. But fat intermixed 
 
 Two HEARTS SIDE BY SIDE 
 
 On the left the heart is normal, on the right it is enlarged and weakened by fat 
 (Copied from Alcohol and the Human Body, by Horsley and Sturge) 
 
 with the fibers of the heart is an entirely different affair 
 from fat distributed in an outside muscle. 
 
 Fat among the fibers of the heart means that the act 
 of pumping is threatened. More than this, the valves of 
 the heart themselves are often so changed by alcohol as 
 to be hindered in their endless occupation of opening 
 and shutting. This means that he who owns the fatty 
 
1 1 6 THE BODY AT WORK 
 
 heart and the weakened valves is far less sure of con- 
 tinued life than he might have been. Since he secured 
 this condition through ignorance, he is not to blame. 
 But sad as is the fact, ignorance never saves men from 
 the results of their ignorance. 
 
 Why do surgeons dread to do anything for the man 
 who uses alcohol ? Because they know only too well 
 that the power of his heart and the elasticity of his 
 arteries have been reduced. They are afraid that his 
 heart -may not rally after they have done what cutting 
 is necessary. In writing of this danger, Sir Frederick 
 Treves says: 
 
 Having spent the greater part of my life in operating, I can assure 
 you that there are some patients that I don't mind operating upon and 
 some that I do ; but the person of all others that I dread to see enter 
 the operating theater is the drinker. He is the most dangerous feature 
 in connection with the surgical life. 
 
 It is because of this constant state of relaxed capil- 
 laries that the nose of the drinker stays red. In his 
 case the nose is frequently a reliable sign of internal 
 conditions. 
 
CHAPTER XV 
 
 AS WE GROW BREATHLESS 
 
 If you were ever thoroughly out of breath, recall the 
 sensations you had at the time. Perhaps you were try- 
 ing to catch a train; perhaps 
 you were running in a relay 
 race. In either case you felt 
 that you must reach the goal 
 at all hazards, and you ran as 
 you had never run before. 
 
 But think of the discomfort 
 of it! Since your legs were 
 young and strong you thought 
 nothing about your muscles, 
 but simply used them hard. 
 You ran fast. Your breath came 
 and went freely, and during the 
 first few moments you drew 
 deep, long breaths of equal length. Soon, however, you 
 found that each breath was shorter than the last; also 
 that they came and went in quicker succession. You 
 began to be uncomfortable. There was a tight feeling 
 
 within you, as if an iron band were closing itself about 
 
 117 
 
 RUNNING AS FAST AS POSSIBLE 
 
Il8 THE BODY AT WORK 
 
 your chest ; as if it prevented you from expanding your 
 lungs to their full size. You wondered how much longer 
 you could keep it up. 
 
 Soon discomfort changed to real distress. Your breath 
 came and went in jerks. Your legs still worked hard 
 and you were running as fast as ever, but there was a 
 pounding in your temples, a buzzing in your ears, your 
 eyesight seemed to fail ; you barely noticed what you 
 passed in your flight, everything grew blurred. You did 
 not see the people w r ho stared at you. You did not 
 know that you were pale and that we who watched you 
 longed to scream out that you must stop running at 
 once. You kept on, and when you reached the goal your 
 friends praised you for your pluck. But you had no 
 power to thank them. You were still breathing in short 
 gasps. This kept on for several minutes. When at last 
 you could breathe comfortably again, perhaps some one 
 asked you if your legs did n't get tired when you ran so 
 fast. And probably you said : " My legs were in good 
 shape. I could have run longer yet, so far as they 
 were concerned. The trouble was, I could n't get breath 
 enough. I was nearly suffocated." In other words, you 
 had gone through a genuine siege of breathlessness, 
 and nothing is much more uncomfortable. 
 
 But why were you breathless ? To answer the ques- 
 tion, follow once more the condition of muscle and bone, 
 tendon and heart, lungs and blood vessels, while you 
 
AS WE GROW BREATHLESS 
 
 119 
 
 were running. Think for a moment of your unelastic 
 tendons as they stayed firmly gripped to their bone 
 attachments. Remember how each one of multitudes 
 of muscles, large and small, shortened and lengthened 
 as, by means of their tendons, they pulled those leg 
 bones of yours up and down and kept them at work. 
 Remember that neither arms nor head nor any other 
 
 67 8 9 
 
 NINE VIEWS OF THE SAME MAN AS HE RAN 
 
 A different set of muscles is at work in each position, so that altogether many 
 muscles are used in running 
 
 (After Schmidt) 
 
 part of your body was quiet as you ran, but that every 
 muscle seemed to work hard in keeping time and step 
 with the movement of the legs. Remember that such 
 violent action as this means that changes are going on 
 in the substance of the living tissue which is exercised ; 
 that these changes involve the giving off of unusual 
 quantities of carbon dioxid; that oxygen is needed by 
 
1 20 THE BODY AT WORK 
 
 the working fibers, and that in order to supply the 
 oxygen and to carry off the carbon dioxid, fresh streams 
 of blood must be hastened to the active muscles with 
 ever-increasing speed. The most immediate, imperative 
 need of each working fiber is to get rid of the excess of 
 carbon dioxid. 
 
 There are then three steps to such a condition of 
 breathlessness : 
 
 1. Exercise violent enough to compel the fibers 
 of the muscles to produce unusual quantities of 
 carbon dioxid. As this gas is produced oxygen is 
 demanded by the fibers. It is indeed as if they 
 themselves were breathing. 
 
 2. The activity of the chest walls as they expel 
 the carbon dioxid from the air sacs of the lungs 
 and replace it with air containing oxygen. 
 
 3. The rapid work of the heart as it receives 
 larger amounts of impure blood than usual through 
 the veins and sends arterial blood to the tissues to 
 carry oxygen and to bring away carbon dioxid. To 
 a large extent it is this forced work of the heart that 
 explains the feeling of breathlessness. 
 
 We were speaking of this matter the other day, and 
 my friend, who teaches physiology, said : 
 
 People used to say that a man was breathless because there was 
 more carbon dioxid in his blood than he could expel through his lungs. 
 But we know better now. We know that it is n't so much the carbon 
 
AS WE GROW BREATHLESS 121 
 
 dioxid although of course that has to be driven off as it is the 
 overtaxed heart that makes us breathless. 
 
 Boys come to me for examination ; and when they complain about 
 their lungs, and say that they get out of breath easily, I know that in 
 all probability most of the difficulty lies elsewhere. The truth is, the 
 heart gets tired from overwork, just as the biceps does, and it is quite 
 as possible to strengthen the heart by training as to strengthen the 
 biceps. At first I put the boys on easy exercises that tax the heart but 
 little ; then day by day I give what is harder, until, almost before they 
 know it, those boys have developed hearts that are strong enough to 
 do good hard work without making them breathless. 
 
 The recognized fact is that we grow breathless in 
 proportion to the force which we put into any exercise 
 in a given length of time ; that is, the faster we do the 
 same thing, the more quickly will breathlessness over- 
 take us. It is easy, therefore, to understand an opposite 
 condition, and to believe that the quieter we are, the less 
 oxygen will the tissues use and the less carbon dioxid 
 will the body have to get rid of. 
 
 The following figures show the amounts of carbon 
 dioxid which a man gives off while sleeping, sitting, or 
 running for a given length of time : 
 
 While asleep 035 gram 
 
 While sitting 060 " 
 
 While running ' . . .165 " 
 
 Men have killed animals after a long hunt, and have 
 found the blood of the arteries so changed in color that 
 it looked like blood from the veins. It was dark and 
 
122 THE BODY AT WORK 
 
 impure because it held an oversupply of carbon dioxid 
 and had lost most of the oxygen which would have 
 given the animal life. From the veins the carbon dioxid 
 had gone through the heart and through the lungs out 
 into the arteries. 
 
 When we are breathless most of the trouble is due to 
 the fact that the heart is overtaxed by the large quantity 
 of blood sent to it from the hard-working muscles to be 
 forwarded to the lungs to be purified of its carbon dioxid, 
 while at the same time the lungs are also overtaxed by 
 their unusual work. 
 
 Those who train for athletic sports learn to keep the 
 balance of the gases in their blood. They know how to 
 manage their running and the work of heart and lungs 
 in such a way that neither will be overtaxed until the 
 end is near. They are willing to be breathless at the 
 very last because they are soon to stop running and 
 catch their breath again. But to get breathless at the 
 beginning of the race means defeat. 
 
 The same is true in horse racing. No good jockey 
 lets his horse get out of breath until the last part of the 
 race. At that time, however, the horse is urged to work 
 the muscles of his legs as hard and fast as possible. It 
 is safe to do this now, for as soon as he reaches the goal 
 his muscles will stop producing such quantities of carbon 
 dioxid and his heart will cease to be overtaxed by its work 
 of pumping this impure blood to the lungs to be purified. 
 
AS WE GROW BREATHLESS 123 
 
 No two horses and no two men or boys are alike in 
 this. Each has his own rate of producing carbon dioxid 
 and of expelling it. Each must therefore discover for 
 himself what the power of his heart is, and learn to 
 increase it. Through practice a man is finally able to 
 adopt a pace in which his heart and his lungs work in 
 unison, a pace which he can therefore keep up with- 
 out overtaxing his heart and without overturning the 
 balance of the gases in his body. He makes the dis- 
 covery that exercise of the large muscles of the body 
 and of the legs calls for much more oxygen in much 
 less time than does exercise of the smaller muscles, and 
 that both heart and lungs need to be trained in relation 
 to each other before he can expect to do hard or rapid 
 work without getting out of breath. 
 
CHAPTER XVI 
 
 WHERE BLOOD CHANGES COLOR 
 
 Place one hand lightly 
 on your chest; place the 
 other on your back between 
 the shoulder blades ; inhale 
 slowly until your lungs are 
 full, then exhale slowly un- 
 til they seem empty. While 
 you do this notice that the 
 breastbone rises, and that 
 the front and rear walls of 
 your chest are forced grad- 
 ually farther apart. 
 
 While you take another 
 long breath and send it 
 out again stand with your 
 hands resting lightly on 
 each side of the body just 
 over your lower ribs. No- 
 tice that it is expansion 
 sideways this time; you also see that the capacity of 
 
 your chest has increased greatly. 
 
 124 
 
 As SHE BREATHES SHE FEELS THE 
 MOVEMENT 
 
MEASURED BY THE DOCTOR 
 
 WHERE BLOOD CHANGES COLOR 
 
 Take a tape measure and get the girth of your chest 
 after you have exhaled all you can, and again after you 
 have drawn in as large a supply of air as your lungs will 
 hold. Learn from these 
 tests that the size of your 
 chest can be increased and 
 diminished at will, and 
 that its size can be in- 
 creased permanently by 
 frequent exercise of this 
 kind. To prove this in 
 your own case, measure your chest to-day ; then for two 
 months take fifteen deep, full breaths three times a day. 
 With each breath expand your lungs as fully as you 
 can without really straining them. At the end of the 
 
 two months measure yourself 
 again and you will find that 
 your chest measure has in- 
 creased. From this you have 
 the right to conclude that 
 your lungs also are larger. 
 
 We often talk of the lungs 
 as if they were a pair of big 
 bags tucked in under the ribs 
 somewhere, waiting to swell out or to sink in according 
 as we use them. In a way the notion of the bag is 
 rather correct, except that instead of two bags, one on 
 
 WITH HIS CHEST EXPANDED 
 
126 
 
 THE BODY AT WORK 
 
 each side, we must think of thousands upon thousands 
 of microscopic bags called air sacs. We must recall 
 what we learned in Good Health, and think of each one 
 of these sacs as the expanded end of a tiny tube that 
 ends in it. We must remember that the tubes them- 
 selves are the small twigs of larger tube branches, and 
 that within the large chamber which the ribs make we 
 
 have two sets of these branch- 
 ing tubes ending in air sacs. 
 Each set is called a lung. The 
 heart lies between the right 
 and left lungs, and is a trifle 
 more on the left than on the 
 right side. 
 
 For the sake of saving time 
 and space a few facts, new 
 and old, must be given under numbered headings. They 
 show how the lungs help us throughout our lives: 
 
 1. Blood that enters the lungs is so dark and so 
 well laden with carbon dioxid although there is 
 also some oxygen in it that we call it impure. 
 Blood that leaves the lungs is so well loaded with 
 oxygen that it has gained a bright scarlet color, 
 and we call it pure, as indeed it is. Even in pure 
 arterial blood, however, there is some carbon dioxid. 
 
 2. Lungs are at work not because they themselves 
 need air, but because they serve as a storehouse and 
 
 A HOLLOW CHEST 
 
WHERE BLOOD CHANGES COLOR 
 
 127 
 
 a place where oxygen and carbon dioxid may change 
 places. Such a central exchange is needed because, 
 as we know, here and there over the entire body 
 each smallest tissue is in need of oxygen and must 
 be relieved of its carbon dioxid. It is in the lungs 
 that blood unloads itself of most of its carbon di- 
 oxid, loads itself up with oxygen, and streams off to 
 some distant destination. 
 Breathing, then, is mainly 
 for the benefit of the tis- 
 sues of the body, not for 
 the sake of the lungs 
 themselves. 
 
 3. All the blood of the 
 body comes to the lungs 
 and goes away again once 
 every twenty-three sec- 
 onds. While it passes 
 through the lungs it does not leave the capillaries, 
 but the capillaries themselves are so closely inter- 
 twined with the air sacs that the two cannot be 
 separated. And while they lie thus near together, 
 with capillaries close about the air sacs, rapid ex- 
 changes are taking place. Oxygen mixed with the 
 other gases of the air is on one side of the animal 
 membrane of the air sac; carbon dioxid, with a 
 little oxygen, is in the blood on the other side of 
 
 TUBES AND AIR SACS OF THE 
 LUNGS 
 
128 THE BODY AT WORK 
 
 the membrane within the capillaries. And as the 
 gases are side by side, two of them the oxygen 
 and the carbon dioxid change places without 
 delay. Oxygen enters the blood from the air sac ; 
 carbon dioxid enters the air sac from the blood; 
 the red corpuscle carriers are loaded in the twink- 
 ling of an eye, and hasten off to unload where their 
 cargo is called for. In the meantime, however, the 
 large supply of carbon dioxid is as unwelcome in 
 the air sac as it is everywhere else in the body. It 
 is therefore expelled as promptly as possible by an 
 outgoing breath. 
 
 In view of these three important facts it is quite evi- 
 dent that large, healthy lungs will be invaluable to any 
 one who wishes to take vigorous exercise, and that, on 
 the other hand, this exercise itself is the very best thing 
 that can be done to develop the lungs. 
 
 A man is always glad when his chest measure seems 
 to show that he has large lung capacity; and many a 
 man with a narrow chest has tried to enlarge his lungs 
 by raising his ribs, by walking with chest forward, by 
 taking exercises which have given him strong arms, a 
 strong back, and firm muscles across the chest. In so 
 far as these exercises made him breathe deeply he helped 
 himself, but unless he held this fact in mind he may not 
 have gained so much as he hoped, for the surest way 
 to increase the size of the lungs is by exercising the 
 
WHERE BLOOD CHANGES COLOR 129 
 
 breathing muscles and by stretching the air sacs them- 
 selves. The entire group of sacs should often be com- 
 pelled to expand more fully than they naturally do in 
 the course of regular daily breathing ; and the best way 
 to expand them is not by standing still and taking 
 deep breaths, but by using large muscles vigorously, 
 thus compelling the lungs to work hard too. 
 
 Many a sagging chest hides from sight multitudes of 
 inactive air sacs that have never been expanded through 
 hard exercise. Nevertheless, each separate 
 one would have worked well and would 
 have increased in size if its owner had 
 been intelligent enough to compel it to 
 gain capacity and power through such 
 hard breathing as comes from fast walk- 
 ing, from running or jumping, or from GROUPS OF AIR 
 lively games played out of doors. 
 
 Unless some care is taken, endless numbers of air sacs 
 may stay inactive for weeks together, and end by being 
 a source of danger. Only by the full breath, which is 
 broad as well as deep, does much air get into the upper 
 corners of the lungs, and these air sacs, left inactive, 
 yield quickest to disease microbes when the attack 
 comes. It is indeed just here that tuberculosis most 
 often begins its work. This dread disease makes rapid 
 advance in the lungs of those who have the largest 
 number of unused air sacs. 
 
130 
 
 THE BODY AT WORK 
 
 
 
 Even for the sake of future health, then, exercise of the 
 lungs is invaluable. This exercise may be secured in one 
 of two ways : 
 
 i. By voluntary full breathing exercises. Ten full 
 breaths taken three times each day will keep the 
 
 air sacs in active con- 
 dition. This is much 
 better than nothing. 
 
 2. By involuntary 
 full breathing. This 
 may be brought about 
 very quickly by giving 
 vigorous exercise to 
 the large muscles of 
 the body. Running and 
 climbing, skipping rope 
 and dancing, anything 
 
 HEART AND LUNGS IN CLOSE that USCS large muscles 
 
 CONNECTION fast will fill the air sacs 
 
 A, left lung; B, heart ; D, tube through anc [ k ee p them in good 
 which blood goes to the lungs to be puri- t 
 
 fied ; E, windpipe through which air goes condition. YOU may 
 to the lungs with oxygen for the air sacs 
 
 for yourself> 
 
 While taking exercise or breathing at any other time, 
 keep in mind the following valuable points learned in 
 Good Health : 
 
 i. Air enters the lungs through tubes that begin 
 with the nose and end in air sacs. 
 
WHERE BLOOD CHANGES COLOR 131 
 
 2. As a rule, breathing should be done through 
 the nose and not through the mouth, because the 
 delicate, damp lining of the nose warms the air and 
 cleans it before it reaches the air sacs. 
 
 3. It is important to send down well-cleaned air, 
 because the inside lining of each air tube is made 
 of the most delicate membrane and is easily injured. 
 Dust that brings tears to the eyes is even more 
 harmful to the lungs. 
 
 With all these facts before him, let the young person 
 who has a narrow or a flat chest set about his own im- 
 provement. Let him apply his knowledge and secure for 
 himself a chest that will be a cause for honest pride. If 
 he wishes to be an athlete, he must not forget that the 
 best developed leg muscles are of little use for running 
 unless the lungs and the heart are able to do their share 
 of the work. For, as some one has said, " We run as 
 much with our lungs and our heart as with our legs." 
 
CHAPTER XVII 
 
 ADULTERATED ALCOHOL AND PATENT MEDICINE 
 
 What a man eats and drinks is so important to the 
 welfare of his body that the following facts about drinks 
 which many people use every day cannot be omitted 
 from a practical book on hygiene. 
 
 Chemists say that in these days he who uses an alco- 
 holic beverage, whether as a drink or as a tonic, cannot 
 know what he is really taking. He has paid for some- 
 thing which contains alcohol, to be sure, but startling 
 revelations have been made about that which he may 
 have received in its place. 
 
 In 1906 Dr. Warren, who was State Food Commis- 
 sioner for Pennsylvania at the time, made an official 
 statement in which he said : 
 
 Out of 600 samples of alcoholic liquors, 450 samples were found to 
 be adulterated. Wood alcohol causing nerve atrophy, convulsions, im- 
 paired vision, blindness, and even death ; salicylic acid, causing intes- 
 tinal derangements, dyspepsia, and kidney diseases ; coal-tar dyes that 
 are active poisons and that cause diseases of the digestive tracts ; sul- 
 phites that have the same effect; red pepper and other powerful irri- 
 tants, are some of the adulterations which lurk in many thousands of 
 bottles and kegs of whisky, wine, beer, and other intoxicants that un- 
 doubtedly will be placed on sale within the next year. The flood of this 
 
 132 
 
ADULTERATED ALCOHOL AND PATENT MEDICINE 133 
 
 poisonous stuff has just commenced. A new legislature will not meet 
 until January, 1907. It is necessary, in the meantime, that public atten- 
 tion be called to the dangers that lie in the use of adulterated drinks. 
 
 On the 1 5th of April, 1907, the general manager of the 
 St. Louis Wholesale Liquor Association wrote a letter 
 to the liquor trade in which he said : 
 
 We retail dealers have allowed the " reduction rogues " to swindle 
 us out of millions by substituting for good whisky, which we paid them 
 for, a compound that would' kill a horse if he drank it. We have unwit- 
 tingly sold this accursed poison to the youth and the flower of our man- 
 hood, many of whom have been crazed, have lost their manhood, their 
 honor, and their all, because they drank it. Their mothers, their sisters, 
 their fathers, their brothers, and their friends are driving us retailers out 
 of business. 
 
 Perhaps we wonder why alcoholic drinks should ever 
 be adulterated. Two reasons are given : 
 
 1. All the wine-producing districts of America 
 and Europe combined do not supply enough of the 
 different kinds of wines to meet the demands of 
 those who wish to use them. 
 
 2. Pure alcohol is heavily taxed, but after the tax 
 has been paid the alcohol can be secretly weakened 
 and cheapened by adding water and drugs to it. 
 Water is added for bulk, and such drugs are put in as 
 will give the desired taste and at the same time make 
 a man feel as alcohol itself makes him feel after he 
 drinks it. Sadly enough for the one who drinks, few 
 things but poison can accomplish this last result 
 
134 THE BODY AT WORK 
 
 Those who understand the danger which lurks in alco- 
 hol may be inclined to ask if, after all, the water and the 
 drugs do not make a safer mixture for a man than the 
 drink which holds more alcohol. The answer is that such 
 poisons as are used in adulterating alcoholic drinks are 
 often even more violent and more harmful to the body 
 than alcohol itself. 
 
 Some time ago the legislature of Ohio asked Dr. Hiram 
 Cox, a distinguished chemist, to make a thorough ex- 
 amination of alcoholic liquors. He worked on the subject 
 for two years, and in a letter afterwards said : 
 
 I have made over six hundred inspections of stores and lots of 
 liquors of every variety, and now positively assert that over ninety per 
 cent of all that I have analyzed were adulterated with the most per- 
 nicious and poisonous ingredients. 
 
 Another letter says : 
 
 I called at a grocery one day where liquor was being sold. A couple 
 of men came in while I was there, and called for some whisky. The 
 first one drank, and the moment he drank the tears flowed freely, while 
 at the same time he caught his breath like one suffocating or strangling. 
 The second man drank and went through like contortions. After they 
 had left I asked the proprietor to pour me out a little in my tumbler. 
 I went to my office, got my apparatus, and examined it. I found it 
 seventeen per cent alcoholic spirits when it should have been fifty, and 
 the difference in percentage was made up by sulphuric acid, red pepper, 
 pellitory, brucine, and strychnine. 
 
 In commenting about it he says, " One pint of such 
 liquor at one time would kill the strongest man." 
 
ADULTERATED ALCOHOL AND PATENT MEDICINE 135 
 
 Two fishermen bought a pint of whisky. They drank 
 it on the banks of the Ohio River, and that afternoon 
 they were found dead with the empty bottle beside them. 
 When the man from whom they bought the liquor heard 
 about their death, he emptied his cask of whisky into 
 the ditch. There was therefore no proof against him. 
 Nevertheless, all who knew what had happened felt sure 
 that the whisky had killed the men. 
 
 No sane man would for a moment think of taking a 
 liquor dealer's recipe book, of which there are many, and 
 putting up for himself a compound of water and poisons 
 such as some of the recipes call for. It would not occur 
 to him that it would be safe for him to drink such a com- 
 pound. Yet the same man runs a greater risk when he 
 buys a drink at any retail or wholesale place ; for the last 
 man who weakened and poisoned the stuff has no more 
 idea than the man who buys it, how many times it has 
 already been weakened and poisoned before it reached 
 his hands. Expensive drinks are quite as unsafe as 
 cheap drinks. 
 
 Judging by its name, our port wine comes from Oporto, 
 Portugal. But Mr. Cyrus Redding once made a report 
 on the subject to a committee appointed by the House of 
 Commons, England. He said that every year Oporto 
 exports 20,000 pipes 1 of wine, but that England alone 
 uses 60,000 pipes of this same wine each year. Where, 
 
 1 One pipe is equal to 126 gallons. 
 
136 THE BODY AT WORK 
 
 then, does the vast quantity of port wine come from that 
 is used in the rest of Europe and in America ? 
 
 Mr. Redding shows that this is the manufactured re- 
 sult of what has passed from hand to hand through the 
 wholesale and the retail dealers. Water, poisons, coloring 
 matter ; more water, more poison, and more color, mark 
 the steps of its progress until the combination of water 
 and chemicals is finally sold as fine port wine imported 
 from Portugal. 
 
 From first to last the work of concealment is so well 
 done that even an expert cannot tell by taste, smell, or 
 color that it is a dangerous compound of chemicals. 
 A chemist, however, with his apparatus can always find 
 the poisons. 
 
 These facts, which no one thinks of denying, do not 
 mean that those who use alcohol are in danger of being 
 killed suddenly by it. We ourselves know that this is not 
 true. Multitudes of people drink more or less frequently 
 throughout their lives, and almost never does even a 
 newspaper reporter hear of a man who has dropped dead 
 because he drank. 
 
 No, the newspaper reporter is not the one to go to 
 when we wish to know about the life-and-death results 
 of drinking. To get such facts we study the statistical 
 tables of life-insurance societies. There we find that he 
 who uses alcohol reduces his chance for life by weaken- 
 ing the power of his body to resist disease microbes. For 
 
ADULTERATED ALCOHOL AND PATENT MEDICINE 137 
 
 definite facts and figures, turn to the eleventh chapter of 
 Town and City. 
 
 Aside from alcoholic drinks, however, chemists find 
 that many patent medicines also contain opium, cocaine, 
 alcohol, and other strong poisons. And just because 
 these poisons are so powerful, the innocent victim may 
 find comfort for a season. His nerves may be quieted, his 
 pain relieved. But later comes the curse. That which 
 seemed so helpful often ends by hastening the progress 
 of the disease it was supposed to cure. This is specially 
 true of consumption. Or, instead, the drug habit may be 
 formed through medicine, and a man may discover too 
 late that he is doomed. 
 
 Chemists testify that most medicines which go by the 
 name of " tonics," " bitters," and relievers of pain of dif- 
 ferent kinds contain a large per cent of alcohol. Often as 
 much as one quarter of the entire liquid in the bottle is 
 alcohol. 
 
 In view of their disclosures these men and others have 
 insisted that innocent people should not be cheated into 
 the use of any poison through ignorance of what they 
 are buying. These scientists have indeed been so much 
 in earnest and so active in their agitation of the subject 
 that at last the United States government has passed a 
 law which helps the case greatly. It demands that the 
 names of every poison in a bottle of patent medicine 
 shall be printed plainly on a label and pasted on the 
 
138 THE BODY AT WORK 
 
 bottle. The amount of alcohol must also be stated on 
 the same label. 
 
 If a bottle of patent medicine bears no such label, it is 
 evident that its contents hide neither alcohol nor poison ; 
 it has no confession to make. If there is a label, remem- 
 ber that, as a rule, each name on it stands for a poison. 
 
 He who is unwise enough to buy patent medicine 
 should balance his mistake by being wise enough to 
 study the label before he uses the contents of the bottle. 
 
CHAPTER XVIII 
 
 EXPERIMENTS IN EATING 
 
 It was a novel thing in the history of the world for 
 men who were connected with a national army to serve 
 their country by being used as a sort of laboratory for 
 
 SOLDIERS WHO SERVED ON THE EATING EXPERIMENTS 
 
 food experiments. But this was done by certain soldiers 
 of the United States army in the year 1903. 
 
 Professor Chittenden of Yale University had decided 
 to conduct some scientific experiments on a rather large 
 scale. He began with himself, enlisted the help of others, 
 and finally had in hand thirteen soldiers whose ages 
 ranged from twenty-two years and six months to forty- 
 three years. Several of these men were Americans. 
 Others were from Porto Rico, from Palestine, from 
 
140 THE BODY AT WORK 
 
 Switzerland, and from England. They were sent to New 
 Haven from the hospital corps of the United States army, 
 and they submitted to the tests as a part of their every- 
 day military duty. 
 
 Close attention was given to the men in several ways. 
 At quarter of seven each morning they were weighed. 
 This was necessary, for they were eating about half as 
 much meat as usual, with somewhat less of other kinds 
 of food, and it was important to know each day whether 
 they were gaining or losing by the new course of diet. 
 
 At seven came breakfast. Here each separate kind of 
 food was weighed before it was given to the man who 
 was to eat it. What he did not eat was also weighed, 
 that Dr. Chittenden might know just how much had 
 been used. Moreover, these men were allowed to eat 
 only such food as was served to them. In other words, 
 for each meal they were told when to eat, what to eat, 
 and how much to eat. All eating between meals was 
 strictly forbidden. 
 
 Aside from this close care about their food the men 
 were not hampered in many other ways. They went to 
 the theater sometimes, worked in the Yale gymnasium 
 an hour a day, had regular drill under their officers, and 
 went to bed at ten o'clock. 
 
 No doubt the whole affair grew monotonous at times, 
 and it has been said that a few of the men were inclined 
 to protest against it. On the whole, however, they went 
 

 
 EXPERIMENTS IN EATING 141 
 
 through it without hesitation, and when they left New 
 Haven at the end of six months, Dr. Anderson, director 
 of the gymnasium, wrote about them as follows: 
 
 The men were not above the average standard physically when they 
 began their work, this standard being set by applicants for positions as 
 
 TEN OF THE SOLDIERS TAKING EXERCISE IN THE GYMNASIUM 
 
 firemen and policemen, not by college students. At the end of the train- 
 ing they were much above the same standard, while the strength tests 
 were far greater than the averages made by college men. 
 
 These tests did not settle all food questions, but they 
 seemed to make it clear that even soldiers may gain 
 
142 THE BODY AT WORK 
 
 strength on much less meat than they have been in the 
 habit of eating. As for the rest of us, science has proved 
 that the work of the body is closely related to the food 
 we give it; that the kind of food makes a difference in 
 the quality of the work; that he who works little, harms 
 himself when he eats much, and that growing children 
 need much more food than their inactive elders. 
 
 All scientists agree that food does two things for 
 the body: 
 
 1. Food builds tissue; that is, it makes the body 
 grow by adding fresh tissue, and it keeps the body 
 new by replacing all tissues as fast as they wear out. 
 
 2. Food produces energy by which the body does 
 work and keeps itself warm. Food so used is the 
 fuel for our engines. 
 
 We eat, then, for the purpose of meeting one or the 
 other of these two great demands of the body, and our 
 success or failure in life may easily turn on what we 
 know or do not know about the value of our food. 
 
 When Professor Chittenden planned meals for his 
 soldiers, his main thought was not as to w r hether he 
 should give them beefsteak, mutton chops, fish, eggs, 
 bread, or vegetables, but whether or not he was giving 
 them the right proportions of certain substances which 
 living bodies need if they are to do good work. This 
 would be easier to understand if our bodies were 
 blocked off in patches, with each separate substance 
 
EXPERIMENTS IN EATING 143 
 
 firmly held in a special district of its own. In point of 
 fact, however, the few general materials out of which our 
 bodies are built are so closely intermixed with each other 
 in blood and tissue that only the chemist can separate 
 them. The next page shows his work in a table which is 
 made up from the reports of the United States Depart- 
 ment of Agriculture. It shows how the materials which 
 the body must have are distributed in some of the foods 
 we eat. In this table the single word "carbohydrate" is 
 used instead of the two words " sugar " and " starch." 
 
 Look over the long list, which is only for reference and 
 not to be memorized, and notice that our entire supply 
 of food comes from living and growing things, that is, 
 from plants or from animals. Plants gather nourishment 
 for themselves from earth and air and water. Animals 
 cannot do this. Instead, by their nature they must live 
 either on the flesh of other animals or on material which 
 plants have gathered and stored up for their own use. 
 
 This fact gives an added interest to the table of foods. 
 Notice that in every case the animal food is rich in pro- 
 teid, and be ready to remember that proteid is the food 
 substance which builds the tissues of the body. That is, 
 when muscle is broken down through exercise, proteid 
 is used to build it up again. 
 
 Notice also that the plant foods in this table are rich 
 in carbohydrates, and bear in mind the fact that carbo- 
 hydrates are the food substances which produce energy 
 
144 THE BODY AT WORK 
 
 FOOD SUBSTANCES AS FOUND IN DIFFERENT ARTICLES OF DiET 1 
 
 
 PROTEID 
 
 CARBO- 
 HYDRATE 
 
 FAT 
 
 WATER 
 
 MINERAL 
 MATTER 
 
 Bread .- . . . . 
 
 8. 9 
 I 3 .8 
 
 16.1 
 
 8 
 
 7- 
 
 2-5 
 
 3-3 
 25-9 
 22.3 
 
 25 
 
 21.2 
 21-5 
 21.8 
 
 134 
 I.O 
 
 6 
 i3-4 
 n-3 
 
 5-8 
 6-3 
 3- 1 
 4-4 
 3-3 
 1.8 
 22.5 
 1.6 
 
 24.6 
 
 0.9 
 
 i-3 
 0.4 
 
 2.1 
 2 I.O 
 2 5 .8 
 17.0 
 
 1 6.6 
 
 56.7 ' 
 71.9 
 67-5 
 79 
 16.9 
 20.9 
 
 5 
 2.4 
 
 3-3 
 74.1 
 
 70-5 
 63-5 
 65-9 
 42.8 
 21.7 
 28.2 
 
 3-3 
 59.6 
 
 5-6 
 19.7 
 62 
 3-9 
 
 22 
 
 9-9 
 73-3 
 "7-3 
 
 24.4 
 7.0 
 16.1 
 
 4.1 
 I. 9 
 
 7.2 
 
 o-3 
 o-5 
 
 O.I 
 
 4 
 33-7 
 28'.6 
 
 22.6 
 
 8.0 
 
 2-5 
 12. 1 
 10.5 
 85 
 
 J -3 
 
 0.9 
 10.5 
 
 9 
 10.7 
 
 9-8 
 8.4 
 3-2 
 
 0.2 
 
 1.8 
 
 o-3 
 i.i 
 i 
 0.4 
 0.6 
 0.6 
 
 54-9 
 38.6 
 66.8 
 63-4 
 
 2 9 .2 
 II.4 
 
 7-3 
 
 74.6 
 
 75-5 
 87 
 34-2 
 48.2 
 
 5-9 
 70-3 
 74-8 
 
 63-5 
 73-7 
 ii 
 88.3 
 10.3 
 4.8 
 18.8 
 
 IS-3 
 
 42-5 
 64.2 
 
 64.5 
 94 
 
 12.6 
 
 9i-5 
 754 
 9-5 
 94-3 
 
 m 
 
 22.3 
 
 4 .8 
 9.2 
 
 5-3 
 
 2-5 
 
 I.I 
 
 I 
 I. 9 
 0.4 
 
 I.O 
 
 0.7 
 
 3-8 
 "3 
 
 1.2 
 I 
 I.I 
 2.6 
 I.O 
 
 3 
 i.i 
 
 i-3 
 
 2-9 
 2-9 
 
 1.8 
 1.8 
 
 i-3 
 0.8 
 
 0.7 
 
 3-5 
 
 i 
 0.7 
 2.9 
 0.5 
 0.8 
 
 O.2 
 
 2-3 
 2.O 
 2.O 
 
 3-9 
 1.4 
 
 Wheat flour ... 
 
 
 Rice . 
 
 
 Potatoes 
 
 Milk 
 
 Cheese 
 Roast beef 
 
 Leg of mutton 
 
 Veal 
 
 Chicken 
 
 Canned salmon . . 
 
 "pprcr 
 
 Butter 
 
 Fresh oysters (solid) . . . 
 Macaroni 
 
 Oyster crackers 
 
 Gingerbread 
 
 Sponge cake . 
 
 Apple pie . 
 
 Squash pie 
 
 Tapioca pudding .... 
 Fresh asparagus .... 
 Dried beans 
 Fresh cabbage . ... 
 
 Green corn 
 Dried peas ... . . 
 
 Fresh tomatoes 
 Bananas 
 
 Fresh cranberries .... 
 Dried prunes . . . . . . 
 Almonds 
 
 Peanuts 
 
 Brazil nuts 
 Soft-shell walnuts .... 
 
 1 Notice that some of the substances in the table are moist while others are dry ; and re- 
 member that before many of the dry foods are eaten a great deal of water is added to them. 
 This is notably true of the cereals, of rice, and of flour. For example, what we buy as one 
 pound of rice at the grocer's comes to the table as nearly four pounds of moist food. The 
 chief difference between dry and moist foods is simply that when we eat dry foods we take 
 less of the food and more water. Vegetables, fruit, meat, milk, eggs, puddings, and pies are 
 moist foods. See the quantity of water in them which the table shows. 
 
EXPERIMENTS IN EATING 145 
 
 THE SAME FOOD SUBSTANCES SHOWN IN A DIFFERENT WAY 1 
 
 PROTEID CARBOHYDRATE 
 
 Bread . . . . 
 Wheat flour . . 
 Oatmeal . . . 
 
 Rice 
 
 Green peas . . . 
 Potatoes. . . . 
 Milk . . . . . 
 Cheese . . . . 
 Roast beef . . . 
 Leg of mutton . 
 
 Veal 
 
 Chicken . . . . 
 Canned salmon 
 
 Egg 
 
 Butter . . . . 
 Fresh oysters . . 
 Macaroni . . . 
 Oyster crackers . 
 Gingerbread . . 
 Sponge cake . . 
 Apple pie . . . 
 Squash pie . . . 
 Tapioca pudding . 
 Fresh asparagus . 
 Dried beans . . 
 Fresh cabbage 
 Green corn . . . 
 Dried peas . . . 
 Fresh tomatoes . 
 Bananas .... 
 Fresh cranberries 
 Dried prunes . 
 Almonds . . . 
 Peanuts . . . . 
 Brazil nuts . . . 
 Soft-shell walnuts 
 
 l These tables are made up from facts supplied by Bulletin 28 (revised edition) of the 
 United States Department of Agriculture. 
 
146 THE BODY AT WORK 
 
 by which the body does its work and keeps itself warm. 
 Proteid also helps in both these directions. 
 
 When more carbohydrate is eaten than is called for 
 by the work of the body, the surplus is stored up as fat ; 
 and this fat is as important to the body for use in times 
 of extra pressure, as is money in the bank for a man who 
 may at some time need more money than he has in hand. 
 Too much fat is, however, a disadvantage, for an over- 
 supply reduces the power of the muscles. 
 
 When more proteid is eaten than the body can use, 
 the surplus is sent off through the kidneys. Those who 
 eat too much meat often overtax their kidneys to such 
 an extent that they suffer from rheumatism and gout. 
 More is said about this in Chapter XXII. 
 
 Babies grow fast and take little exercise, hence their 
 food milk contains both proteid and carbohydrate. 
 Later on the same child will be a man; he will then 
 grow little and exercise much, and will therefore need 
 several times as much carbohydrate (fuel food) as pro- 
 teid (tissue food). 
 
 Study the table of foods carefully and decide which 
 articles may be wisely put together for the same meal. 
 Professor Chittenden himself had these food substances 
 in mind when he planned meals for the soldiers. He 
 knew that all kinds of meat and some kinds of vegeta- 
 bles are rich in proteids ; that grains and vegetables are 
 specially rich in sugar and starch (carbohydrates) ; that 
 
EXPERIMENTS IN EATING 
 
 mineral matter which we need 
 also found in most meats and 
 as we do, that the great food 
 questions turn upon the pro- 
 teids and the carbohydrates. 
 In giving directions, there- 
 fore, he was careful to order 
 a mixed diet of carbohydrates 
 and proteids for the same 
 meal. When, for example, he 
 selected beans, cheese, or eggs, 
 he gave little if any meat ; in- 
 stead, he provided foods rich 
 in starch or sugar, with vege- 
 tables and fruit, for example, 
 or with some simple sweet 
 dessert. 
 
 Housekeepers succeed best 
 when they too keep sight of 
 these proteid and carbohy- 
 drate facts. They are then 
 able to make wise and nour- 
 ishing combinations for their 
 families. They know why a 
 man receives as much nour- 
 ishment from eggs and beans 
 and cheese, as from steak and 
 
 comes in table salt and is 
 vegetables. And he saw, 
 
 THIS SHOWS WHAT PROPORTION OF 
 
 THE HUMAN BODY is COMPOSED OF 
 
 EACH SUBSTANCE WHICH WE TAKE 
 
 AS FOOD 
 
 Little carbohydrate appears because 
 most of the sugar and starch which we 
 eat is used up in the shape of heat and 
 muscular work and sent from the body 
 as carbon dioxid. When we eat more 
 carbohydrate than we need, the sur- 
 plus is stored up as fat. The diagram 
 shows that the body keeps a good deal 
 of this on hand ready for use 
 
 (Copied from Practical Hygiene, by Alice 
 Ravenhill) 
 
148 THE BODY AT WORK 
 
 roasts. They know why boiled potatoes alone are not 
 so nourishing as creamed potatoes, and why pickles and 
 tea and coffee are almost useless as food. 
 
 Just here it should be stated that food is needed not 
 for nourishment alone, but for bulk as well. Were it not 
 for this we might be content to have our food condensed 
 to small pellets and swallowed quickly with a mouthful 
 of water. The objection to this simple scheme is that 
 the extended size and length of the stomach and the 
 food tube have to be taken into account. They require 
 food which shall be bulky enough to be acted on. 
 Vegetables and fruit have special value for this reason. 
 The same is true of graham bread and grains with the 
 hulls on. Much of the tissue of vegetables and fruit is 
 not useful as food, but it is of great value in giving bulk 
 for the walls of the tube to exercise themselves upon. 
 
 There are those who feel very sure that they must eat 
 meat of some sort every day. So indeed they must if they 
 can provide themselves with proteid in no other way. 
 But there are multitudes of equally active people who 
 are intelligent enough to know that they can find all 
 the proteid they need in other foods than meat. 
 
CHAPTER XIX 
 
 CATS UNDER THE X-RAY 
 
 It is quite possible that the soldiers and athletes who 
 shared in the eating experiments had no very definite 
 notion about that which was to happen to the food 
 which they swallowed, and it may easily be that some 
 of them had not so much as heard about Dr. Cannon's 
 experiments on cats. 
 
 These experiments were carried on in the laboratory 
 of the Harvard Medical School, and the record of the 
 work was published in 1898. Cats were chosen because 
 they are easy to get hold of, ready to eat when they are 
 fed, ready to sleep at almost any time, and easily con- 
 trolled. Even among cats, however, Dr. Cannon had to 
 choose carefully, for only those who were good-natured 
 were useful to him. 
 
 Having made his choice, he took bread, mixed into it 
 a harmless chemical called bismuth, fed it to his cats, and 
 waited for results. The bismuth was put in for just one 
 reason. Its presence in the food made it possible to get 
 a shadow of the shape of the stomach by means of X-rays. 
 From shadows he hoped to discover, very definitely, how 
 
 the stomach moves during the time that it is digesting 
 
 149 
 
150 THE BODY AT WORK 
 
 its contents. Dr. Cannon was fortunate in the cats he 
 chose, fortunate in his helpers, and fortunate in what he 
 was able to learn through the X-rays; for he learned 
 facts which had never been proved before. 
 
 After being fed the cat was put in place for its shadow 
 picture. The particular cat which I have in mind was 
 fed at fifty-two minutes after ten in the morning. At 
 eleven o'clock work was well under way in the stomach, 
 and once every half hour after that, until twelve minutes 
 after six in the afternoon, the kindly cat consented to be 
 put in place to have its shadow studied. Dr. Cannon 
 traced the shadows one by one, so that an exact record 
 was kept of the size of the stomach from the time of 
 the hearty feeding until there was nothing left to be 
 digested. 
 
 During this time there had been an interesting course 
 of events. When first seen the stomach looked like a 
 small leg of ham with a curled-up tail to it. But when 
 six o'clock came, the leg shape had disappeared entirely, 
 leaving nothing but the tail to show where the food had 
 been. Moreover, at this time, the cat seemed hungry and 
 called for food, with which it was promptly rewarded. 
 
 The diminishing size of the stomach was perhaps one 
 of the smallest lessons learned that day; for while the 
 cat slept, and while the X-rays were focused on its 
 stomach, another fact was noted. It appeared that food 
 which had newly arrived stayed quietly in the upper 
 
CATS UNDER THE X-RAY 
 
 12.00, 
 
 end of the stomach as if it were in 
 a reservoir. Here the saliva which 
 had been swallowed with the food 
 had a longer time to do its share in 
 the work of digestion. But as fast 
 as supplies were needed further on, 
 this reservoir contracted itself and 
 sent its contents forward a little at 
 a time. 
 
 It was also seen that the firm walls 
 of the lower part of the stomach had 
 begun to contract in a series of wave- 
 like movements. These waves started 
 near the middle of the stomach and 
 moved towards the smaller end of 
 the elastic bag. They followed each 
 other in regular succession. Once 
 every ten seconds a new wave took 
 its start from about the same spot 
 and traveled the same course down 
 to the smaller end. 
 
 Indeed, whenever the shadows 
 were studied during that day, these 
 waves were seen to be following CI 60(/ 
 each other with unceasing regular- CONTRACTION OF CAT'S 
 
 ity. Moreover, as time passed, and STOMACH (MUCH RE- 
 DUCED) DURING DICES- 
 
 as digestion progressed, this middle 
 
 400, 
 
 ,4.30. 
 
 5.30^ 
 
 TION 
 
152 THE BODY AT WORK 
 
 part of the stomach grew gradually more and more 
 slender, like a neck, while the larger end stayed large 
 for a longer time. 
 
 Through his study of shadows Dr. Cannon learned 
 that within about fifteen minutes after food is swallowed, 
 a slender jet of softened food goes with a spurt through 
 an opening at the lower end of the stomach and out into 
 the tube which is the beginning of the small intestine. 
 
 For all animals, including man, this exit for the con- 
 tents of the stomach is guarded by a strong muscle 
 called the pylorus, or keeper of the gate. And well does 
 this keeper do its work. Sometimes, with every wave 
 that rolls in its direction, it opens wide enough to allow 
 a spurt of digested liquid food called chyme to go 
 through. But sometimes it stays persistently shut while 
 wave after wave pushes in vain in its direction. 
 
 For the sake of getting an explanation of this uneven 
 action of the pylorus, Dr. Cannon induced the cat to 
 swallow a small specially prepared tablet made up of 
 starch paste on the outside and of bismuth the size of 
 a pea at its center. He then watched the progress of this 
 pellet in the stomach. He saw it stay for a long time in 
 the large, bulblike end ; saw it gradually make its way 
 farther and farther down as it was sent forward by the 
 waves of contractions ; and finally saw that for forty-two 
 minutes after the pellet reached the pylorus that dili- 
 gent gate keeper allowed nothing to pass onward. 
 
CATS UNDER THE X-RAY 153 
 
 Over and over again the round bit of bismuth and 
 the mass of soft food in which it floated, came up to the 
 pylorus as if to demand free passage through. And over 
 and over again, just as often, the soft as well as the hard 
 was positively rejected and sent shooting backwards, only 
 to come again and again to be rejected. 
 
 This was kept up until finally the most fluid of the 
 food was refused no longer. It went onward. Later yet 
 the pylorus seemed to give up all protest. It seemed to 
 conclude that there was no hope of ever softening the bis- 
 muth. This also was then permitted to go on in company 
 with food which was well prepared for advancement. 
 
 From this experiment it is evident that the disadvan- 
 tage of any hard substance in the stomach is not simply 
 that it is itself slow in passing on through the pylorus, 
 but that it delays the progress of even such food as has 
 already been reduced to chyme food which should be 
 receiving its next course of treatment in the food tube. 
 The main objection to slow digestion is that after food 
 has stayed too long in the stomach it grows sour and 
 gives off gases which stretch the walls of the stomach 
 and cause distress of various kinds. 
 
 The next time you eat in a hurry .and are tempted to 
 swallow unchewed lumps of food, think of all this and 
 control yourself in time. 
 
 During the X-ray experiments there came an unex- 
 pected turn to affairs one day. Thus far Dr. Cannon had 
 
154 
 
 THE BODY AT WORK 
 
 been fortunate enough to have dealings with amiable cats 
 only. They had eaten when he wished, had been quiet 
 and well-mannered during the experiments, and had slept 
 when required. In addition, their stomachs had gone 
 
 Gall_ 
 bladder 
 
 Bile Duct 
 
 Intestine 
 
 FromiheLiver 
 1 1 Pylorus 
 
 ^Pancreatic Ihict 
 
 THE HUMAN STOMACH 
 
 Food reaches the stomach from the mouth through the oesophagus. While 
 digestion goes on, bile runs from the liver directly into the intestine ; at 
 other times the opening of the bile duct is shut, and instead of entering the 
 intestine, bile passes into the gall bladder, where it is stored until needed. 
 The outline of the pancreas is shown by a dotted line 
 
 steadily to work when food was put into them, and had 
 kept ploddingly at it until digestion was accomplished. 
 
 But a different type of cat came to Dr. Cannon's hands 
 one morning. This one ate as promptly as the others, 
 and when the X-ray was arranged the shadow showed at 
 
CATS UNDER THE X-RAY 155 
 
 first that the usual regular wave action of the muscular 
 walls was taking place. Suddenly, however, the animal 
 lost his temper. He seemed to feel outraged that any- 
 thing should be going on which he did not understand. 
 He refused to purr as did the other cats ; he insisted on 
 being released. Being in such a state of mind, he was 
 useless and had to go. But before he was dismissed it 
 was seen that all the action of the waves had stopped. 
 So much so, indeed, that the stomach was as inactive as 
 if it were empty of food. 
 
 This led to close observation of the connection be- 
 tween the feelings of a cat and the behavior of its 
 stomach during digestion. These observations in turn 
 led to the startling discovery that whenever a cat is un- 
 happy or disturbed in its mind by anger, anxiety, or dis- 
 tress of any description, the muscular action of the 
 stomach comes to an end. 
 
 To prove this conclusively, those who carried on the 
 experiments were obliged to tease a well-disposed cat a 
 little, even while it was under the rays. Before the teas- 
 ing it purred gently, and the wave contractions swept on 
 with rhythmic regularity. But when the teasing began, 
 and when the cat began to feel mental distress and 
 to show it, every wave ceased the stomach stopped 
 its work abruptly and absolutely. If, then, Dr. Cannon 
 stroked the cat, it was at once happy; it purred, and 
 with that purring began again the squeezing and the 
 
THE BODY AT WORK 
 
 monotonous, regular progress of the waves along the 
 walls of the stomach. 
 
 Doctors have always known that an unhappy man 
 does not digest his food so well as the same man when 
 he is happy; but none have known just why this is so. 
 It is evident, however, that there is some close connec- 
 tion between happiness and the power of the stomach to 
 keep up the squeezing movement of its waves. 
 
 In view of this discovery, nothing could be clearer 
 than the fact that if we wish good work from our own 
 stomachs, we must be neither worried, nor anxious, nor 
 angry, either during the time that we are eating or 
 so long afterwards as food is in our stomachs waiting 
 to be digested. For the simple sake of health, there- 
 fore, the calm and happy mind is greatly to be desired. 
 
CHAPTER XX 
 
 FROM FOOD TO BLOOD, OR PERISTALTIC ACTION 
 AND THE VILLI 
 
 In the same laboratory of the Harvard Medical School, 
 and probably on the identical cats already described, a 
 second set of experiments was to show what the history 
 of chyme is after it has gone through the pylorus into 
 the tube which receives it. 
 
 This tube, which in man is about twenty feet long 
 and about three inches around, is folded back and forth 
 in compact compass just below the stomach. It is called 
 the small intestine ; and within it go on some of the 
 most marvelous of our involuntary muscular contractions. 
 
 The entire- scientific world was in doubt as to pre- 
 cisely what happens in the tube until, through the X-ray, 
 through the cats, and through Dr. Cannon's continued 
 experiments, the mystery became a series of surprising 
 facts that could be understood perfectly well. 
 
 Previously scientists had known that chyme, as it 
 leaves the stomach, is as liquid as pea soup ; that certain 
 juices are promptly poured upon it from the liver, the 
 pancreas, and the lining of the tube; and that, in its 
 most liquid state, the food passes through the sides of 
 
 157 
 
158 
 
 THE BODY AT WORK 
 
 the small intestine and is sent into the blood supply of 
 the body. 
 
 All this has been acknowledged for many years. It 
 has also been stated distinctly very often that food 
 
 THE FOOD TUBE AND ITS CONTENTS 
 
 A, the tube as it contracts at regular intervals ; B, the contents of the tube 
 after the first contraction ; C, after the second contraction ; Z>, after the third 
 contraction. The line through the middle of the oval piece shows where 
 each was divided by the tube as it tightened just there. The arrows show 
 how the new halves were alternately forced apart, and then driven together 
 again by the repeated contractions of the tube itself 
 
 which leaves the stomach as chyme is to be called chyle 
 while it makes its journey through the long tube. It is 
 well to remember these new words and these statements, 
 for they make the continued history of digestion easier 
 to understand. 
 
FROM FOOD TO BLOOD 159 
 
 After the stomach had done its work through waves 
 of motion ; after gastric juice had softened and dissolved 
 the food by degrees ; after the pylorus had allowed such 
 chyme as was soft enough to pass through its narrow 
 portal; after bile from the liver and pancreatic juice 
 from the pancreas had turned this chyme to chyle, then 
 followed what proved to be a most surprising discovery. 
 
 At first the X-rays showed the shadow of the chyle as 
 it lay along in the various loops of the folded tube. All 
 was inactive and quiet for a season. The chyle was 
 motionless and gave no sign of progress. But slight 
 warnings followed, a quiver at first, a mere agitation. 
 Then, without further delay, activity began in earnest. 
 The stretched-out length of chyle within an entire loop 
 was suddenly divided into separate bits. Each bit was of 
 the same size as all the others. The tube indeed, without 
 apparent cause, had tightened itself at regular intervals. 
 Like a flash it had divided its contents into a series of oval 
 masses of equal size. After this it halted for a moment. 
 But within two seconds there was another contraction, 
 and each bit was now divided through the middle. Their 
 halves were compelled to unite with neighbor halves on 
 either side, and a series of new whole ones appeared. 
 
 Thus, back and forth with every two seconds of time, 
 the rapid peristaltic action was continued. 
 
 While it lasted the small particles were alternately so 
 quickly divided and so quickly forced together again that 
 
160 THE BODY AT WORK 
 
 Dr. Cannon speaks of them as rushing together " with 
 the rapidity of flying shuttles, the little particles flitting 
 towards each other and the larger segments shifting to 
 and fro, commonly for more than half an hour without 
 cessation." 
 
 In the meantime the food within the tube was ad- 
 vanced but slowly on its way. It seemed to stay in 
 place for no other purpose than to be acted on by the 
 squeezing and the relaxing of the tube. Whether the 
 chyle was thin or thick, whether the activity of the tube 
 was slower or more swift, the squeezing was kept up so 
 unweariedly that each particle of chyle was affected by 
 it. All that lay within the folds and turns of the small 
 intestine was brought into contact with the sides of the 
 tube tens of thousands of times while it was gradually 
 being absorbed. That which could not be used went on 
 into the large intestine, whence it would finally leave 
 the body. 
 
 To an ignorant person this endless activity might 
 seem to be a waste of energy and a needless hindrance 
 to the chyle as it works its way along. In point of fact, 
 however, rapid movement of chyle through the food 
 tube would be a distinct disadvantage; for, from the 
 time food is swallowed until its journey is ended, the 
 one necessity is that it should be thoroughly prepared 
 to be used by the regiments of threadlike villi which 
 line the small intestine. Chyle, indeed, is improved by 
 
FROM FOOD TO BLOOD 
 
 every juice and every squeeze which it receives before 
 
 it is absorbed by the villi. So true is this, that food 
 
 which does not get the treatment it needs will be 
 
 rejected by each villus which it 
 
 meets as it travels downward, and 
 
 will end by forming part of the 
 
 final waste of the body. When 
 
 this occurs to food which we have 
 
 taken the pains to cook and chew 
 
 and swallow, not only does the 
 
 body lose the strength it should 
 
 have had, but the tube itself is in 
 
 danger of becoming clogged. And 
 
 here it is that we face again the -^ 
 
 problem of bo'dy waste. 
 
 With all that we eat, there is, 
 of course, much that can never be 
 turned into chyle and blood. As 
 we know, however, this is useful as 
 bulk. But nothing hinders diges- 
 tion much more, or breaks down 
 general health much faster, than 
 
 , 1 . 1 A cut through the wall of the 
 
 the results which come from re- tube, showing some dark blood 
 taining waste in the body after it vessels and four villi 
 should be sent off. Even as meat and vegetables decay 
 in the pantry on a warm day, so too is it with waste in 
 the body. Both in the pantry and in the food tube decay 
 
 VlLLI THAT FORM THE 
 
 VELVET LINING OF THE 
 FOOD TUBE 
 
1 62 THE BODY AT WORK 
 
 comes from the action of microbes, and from both places 
 decaying food should be cleared away promptly. The 
 habit of getting rid of waste at a definite hour each 
 day, whether in the morning or in the afternoon, is of 
 priceless value ; for that which the villi reject is worse 
 than useless to the body. 
 
 It would seem, then, that from first to last each 
 mouthful of food which we swallow is being put into 
 shape for the villi, and that they use it or not without 
 the slightest reference to our wishes in the matter. 
 This indeed is true; and the number of these inde- 
 pendent workers is counted by the hundred thousand 
 and the million. Each separate one is a tiny finger- 
 shaped structure, ready to absorb such chyle as shall 
 meet its demand ; each stands beside its neighbor, help- 
 ing to make the soft, velvety lining of the twenty feet 
 of tubing; each does its independent work; yet all are 
 united in drawing nourishment from the chyle and in 
 sending it on to the body through the blood. 
 
 Just here certain facts should be reviewed and 
 condensed : 
 
 1. It is through the lining of the small intestine 
 that all substances must pass whether proteid or 
 carbohydrate, fat, water, or salt which are to enter 
 the blood from the food we swallow. 
 
 2. The villi are, in point of fact, the lining it- 
 self drawn up into slender tubes for the sake of 
 
FROM FOOD TO BLOOD 163 
 
 increasing the surface against which the chyle must 
 be pressed. 
 
 3. Food passes through the villi much as lymph 
 and plasma pass back and forth through the sides 
 of the tubes that carry blood. This food must, 
 therefore, be very liquid, for the villi cannot absorb 
 any solid substance. 
 
 4. The great object of peristaltic action is to 
 wash the chyle up against the villi, that they may 
 be constantly bathed with fresh supplies of it. 
 
 5. The mouth with its teeth and its saliva softens 
 food and prepares it for swallowing; the stomach 
 with its gastric juice softens it still further and pre- 
 pares it for the pylorus ; the food tube with its con- 
 tributions from the liver and the pancreas gives to 
 what we eat its final preparation for the villi. 
 
 When chyle which is squeezed against the villi is 
 such as they can use, they absorb it and send it on 
 through other tubes into the current of the blood. 
 When, however, this chyle is not liquid enough, or 
 not changed enough in other ways, they refuse it as 
 absolutely as if it were a poison to them. 
 
 For each of us almost any well-cooked food can be 
 turned into chyle which will pass through the villi ; 
 yet many a thin man and many a half-nourished woman 
 shows by every sign of face and figure that the villi are 
 not getting what they can accept. 
 
1 64 
 
 THE BODY AT WORK 
 
 A 
 
 In almost every such case the explanation lies in some 
 mistake which the person is making. Perhaps he eats 
 so fast and chews so little that saliva does not have a 
 chance to do its share of work. Perhaps he is so busy 
 
 just before and just after eating, 
 that blood is drawn away from 
 the stomach, leaving it less vig- 
 orous than it should be. Per- 
 haps he worries so much, is 
 so anxious and troubled about 
 many things, that gastric juice 
 fails to form and is thus kept 
 from doing its part of the work. 
 Or it may be that the unfortu- 
 nate person has overeaten until 
 his whole digestive system has 
 rebelled. Whatever the cause, 
 we know that we are nourished 
 or starved according as we have 
 been successful or not in pre- 
 paring chyle for its last exami- 
 nation. If teeth and tongue, 
 saliva, stomach, gastric juice, 
 bile, and pancreatic juice have done their work well, the 
 final test will be successfully met and passed; the villi 
 will accept the food, and we shall be nourished. If the 
 test is not met, we shall suffer from lack of nourishment. 
 
 A VlLLUS CUT DOWN THROUGH 
 THE MIDDLE 
 
 A, a cell which manufactures mu- 
 cus ; B, the outside layer, which 
 absorbs chyle; C, capillaries to 
 supply each villus with blood; 
 Z), lymphatic 
 
CHAPTER XXI 
 
 GLAND LABORATORIES FOR THE AID OF APPETITE 
 AND GENERAL HEALTH 
 
 Although they did not understand what they were 
 doing, dogs no less than cats have helped scientists who 
 have tried to explain the laws of digestion for us. One 
 such dog had a small tube fastened so ingeniously to his 
 mouth that the saliva ran into it as fast as it was formed. 
 Professor Pawlow watched and described the tests one 
 after the other : 
 
 I now offer such an animal a piece of flesh, and, as you see, the tube 
 fills up at once with saliva. I stop tempting the dog, hang on a new 
 test tube, and give it a few pieces of flesh to eat ; once more a strong 
 secretion of saliva results. A new tube is now attached to the funnel, 
 the dog's mouth is opened, and a pinch of fine sand is thrown in ; again 
 there is a flow of saliva. One may employ a number of substances in 
 this way, when a similar effect is always produced. 
 
 Many different students have established the fact that 
 the mouths of dogs and of men too are supplied with 
 three sets of salivary glands, and that for dogs and men 
 alike, one or the other of the two following causes are 
 enough to make saliva flow: 
 
 1. A great desire for some special kind of food. 
 
 2. The chewing of the food. 
 
 165 
 
1 66 
 
 THE BODY AT WORK 
 
 Prove these statements for yourself. Think of the most 
 delicious thing you know anything about, and notice the 
 effect on your mouth. Then again, when meal time comes, 
 or even now if you can get it, take a dry crust and see what 
 you can do with it by the mere act of chewing. Use your 
 
 jaws vigorously, and before 
 long you will find that you 
 have turned that dry bread 
 into something as easy to 
 swallow as a mouthful of 
 mush. 
 
 A wise man with weak di- 
 gestion often chooses toast, 
 crackers, and crusts rather 
 than the most delicate cus- 
 tards. He makes this choice 
 A SALIVARY GLAND because he knows that dry 
 
 A, artery; V, vein; N, nerve; T, food requires more chewing 
 tongue ; Z>, the tube through which . 
 
 saliva, manufactured by the gland, than food which IS SOlt, and 
 
 is emptied into the mouth ^ for ^ reasQn it w j n re _ 
 
 ceive the most from his salivary glands. He recognizes 
 
 the value of three facts : 
 
 i. Saliva has the power to turn starch a carbo- 
 hydrate which cannot be used by the villi into 
 sugar, a carbohydrate which can be absorbed into 
 the body. This is a different kind of sugar from that 
 which we eat in food or in candy. Saliva also helps 
 
GLAND LABORATORIES 
 
 167 
 
 change certain sugars which are hard to absorb, into 
 other sugar which is easy to absorb. 
 
 2. The more saliva we mix with the carbohydrate 
 which we eat in bread, potatoes, and other foods, the 
 better prepared will that carbo- 
 hydrate be for its next course of 
 
 treatment. 
 
 3. Saliva which we swallow 
 with our food will continue to act 
 upon it during the time that it 
 stays quietly in the large, upper 
 end of the stomach, waiting to 
 go on. 
 
 Carbohydrate, however, does not 
 stand alone in its need of help from 
 the mouth. A baby is allowed to draw 
 no more than the finest stream of milk 
 
 through the mouthpiece of his bottle. BRANCHES OF A GASTRIC 
 
 Those who feed the child seem to GLAND HlGHLY MAGNI ' 
 
 FIED 
 
 know that when milk reaches the ~ 
 
 Gastric juice is here manu- 
 
 stomach it is curdled at once, and that factured for the use of the 
 it is much better to have it curdle in 
 small flakes, that can be more easily digested, than in 
 one large lump which will be slow in digesting. Young 
 babies who are allowed to drink milk rapidly from a tum- 
 bler are not likely to gain so much nourishment from this 
 milk as they would if it reached the stomach a little at a 
 
1 68 
 
 THE BODY AT WORK 
 
 time. The same is so true for older people, too, that wise 
 doctors strongly advise all human beings, whether young 
 or old, to take their milk in sips and not in a pouring 
 stream which will curdle in a mass as soon as it reaches 
 the stomach. Milk is swallowed slowly, therefore, not 
 because it needs the help of saliva, but because it is 
 
 more quickly digested when it 
 has been curdled in flakes. 
 
 After being swallowed, food 
 finds itself in the region of the 
 stomach where there is rhythmic 
 agitation from the waves of con- 
 traction. Here gastric juice acts 
 upon it. 
 
 This colorless acid fluid can 
 dissolve almost any proteid sub- 
 Each spot shows the mouth of stance. A dog swallows an un- 
 
 a gastric gland through which 
 
 gastric juice flows into the chewed chunk of raw meat and 
 stomach the stomac h digests it, not by 
 
 tearing it to pieces, but, in a real way, by dissolving 
 it through the aid of gastric juice. Even the human 
 stomach easily digests unchewed raw meat, but cooked 
 meat needs more chewing and more help from the saliva. 
 Moreover, gastric juice is needed for both cooked and 
 uncooked meats. 
 
 Numberless small gastric glands manufacture this 
 liquid. They are packed snugly side by side within the 
 
 A FRAGMENT OF THE LIN- 
 ING OF THE STOMACH MAG- 
 NIFIED 20 DIAMETERS 
 
GLAND LABORATORIES 169 
 
 lining of the stomach. There each is supplied with its 
 separate tube, ending in its own special outlet ; and the 
 juice which these hosts of glands manufacture and empty 
 into the stomach is of immense value in continuing the 
 work of getting food ready for the villi and the blood. 
 
 As to what makes gastric juice flow fastest, and how 
 the supply may be more or less controlled, Dr. Pawlow 
 learned many things through his tests with the dogs. 
 
 The stomach has been washed out half an hour ago, and since then 
 not a drop of gastric juice has escaped. We begin to get ready a meal of 
 flesh and sausage before the animal, as if we meant to feed it. We take 
 the pieces of flesh from one place, chop them up, and lay them in 
 another, passing them in front of the dog's nose, and so on. The animal, 
 as you see, manifests the liveliest interest in our proceedings, stretches 
 and distends itself, endeavors to get out of its cage and come to the 
 food, chatters its -teeth together, swallows saliva, and so on. Precisely 
 five minutes after we began to tease the animal in this way the first 
 drops of gastric juice appear. The secretion grows stronger and stronger 
 till it flows in a considerable stream. The meaning of this experiment 
 is so clear as to require no explanation : the passionate longing for food, 
 and this alone, has called forth under our eyes a most intense activity 
 of the gastric glands. 
 
 In carrying on these experiments Professor Pawlow 
 made it plain that dogs should not simply be tempted, but 
 should be really fed with that which has tempted them. 
 
 Several other facts were brought out by the same tests. 
 Each was valuable from a scientific point of view, and I 
 give them in close succession: 
 
170 THE BODY AT WORK 
 
 1. The more eagerly a dog desires food the more 
 gastric juice will flow. 
 
 2. Gastric juice flows fastest and longest in con- 
 nection with food that is enjoyed the most ; for some 
 dogs this is raw meat, for others cooked meat, etc. 
 Dogs have preferences as well as men. 
 
 3. The mere fact that something is in the dog's 
 stomach does not make the juice flow. 
 
 4. We all understand that the more the juice 
 flows, the better will the food digest. 
 
 From these important facts, learned from the study of 
 digestion in dogs, men have learned why it is that a 
 good appetite helps digestion. Indeed, those who make 
 an application of the facts to their own lives come to the 
 conclusion that hunger, if it is not too long continued, 
 is one of the greatest blessings of life, and that he who 
 eats only when he has earned an appetite for food is 
 surest to gain the most nourishment from that which 
 he puts into his stomach, because while it is there it 
 will receive the richest supply of gastric juice. 
 
 But aside from digestion itself there is the great matter 
 of preparing food for the glands even before we eat it. 
 The fact that we cook our food is an enormous help in 
 two important directions : 
 
 i. Cooking kills microbes. Recall the typhoid ex- 
 periences of the cities on the Merrimac River, as 
 they are described in Town and City (Chapter XV), 
 
GLAND LABORATORIES 
 
 171 
 
 and remember that boiling would have killed the 
 disease microbes and made the water safe to drink. 
 The same treatment will 
 kill other disease microbes 
 whether they are in milk or 
 meat or food of any kind. 
 
 2. Cooking breaks starch 
 cells open and makes it pos- 
 sible for saliva to get hold of 
 
 the Starch and help turn it FROM THE SEED OF' THE BEAN 
 tO SUgar. The larger granules are starch, 
 
 We know already that unless the smaller ones are proteid 
 this starch is turned to sugar, every villus in the long 
 tube will reject it, whereas if the change has been made 
 it is quite sure of being accepted. 
 
 In cooking oatmeal and other 
 breakfast foods that hold a good 
 deal of starch, there is often 
 danger that those who do not 
 understand the main object of 
 cooking will call food ready to 
 eat even when heat has not been 
 applied to it long enough. An 
 hour of boiling for oatmeal and 
 half an hour for other more finely powdered grains is 
 none too long for best results. Nothing is gained and 
 much is lost by eating cereals that are undercooked. 
 
 A BIT OF POTATO TO SHOW 
 STARCH GRANULES 
 
172 THE BODY AT WORK 
 
 This chapter teaches several important facts about 
 eating: 
 
 1. We should so live and work as to have an appe- 
 tite for our food. 
 
 2. We should chew food thoroughly and give pro- 
 longed stimulation to salivary glands, thus fitting the 
 food for the stomach and for the pylorus. 
 
 3. We should enjoy our food, thus stimulating 
 both salivary and gastric glands. 
 
 4. Foods that contain starch should be well 
 cooked and well chewed. 
 
 Still another fact, shown in a previous chapter, is that 
 for our best good we should be free from mental anxiety 
 of every sort before we eat, while we eat, and after we eat. 
 
CHAPTER XXII 
 
 GLAND LABORATORIES INFLUENCED BY ALCOHOL 
 
 In case you are thin enough to do it, you might slip 
 your ringers up under the edge of the lowest ribs on your 
 right side. There you will feel the smooth outline of the 
 largest gland in your body. It weighs between three and 
 four pounds, and it is to this place that the villi send 
 much of that which they gather from the chyle. Indeed, 
 it is only after this gathered liquid food has gone into the 
 liver, and after a valuable substance called glycogen has 
 been made out of it, that it is ready to be used by the 
 tissues of the body. The liver, then, is a chemical labora- 
 tory where food gets its final preparation for the blood. 
 
 More than this, a large part of the impure or venous 
 blood, on its way back to the heart from the capillaries, 
 passes through the same great gland. There it is re- 
 lieved of broken-down tissue and other waste which it 
 has gathered from the body. From part of this waste 
 the liver manufactures bile. Here,, then, we have the 
 circle of the occupations of the liver: 
 
 i. It changes liquid food which it receives from 
 
 the villi into glycogen, which the body needs for 
 
 nourishment. 
 
174 THE BODY AT WORK 
 
 2. It takes certain wastes from the blood, makes 
 them over, and forwards them in the blood to the kid- 
 neys, to be separated there and sent from the body. 
 
 3. It manufactures bile as needed. This is sent 
 to the small intestine where it helps digestion and 
 afterwards escapes with the other wastes of the 
 food tube. 
 
 Clearly enough, no man who knows these facts and 
 who wishes to make sure of his health will care to 
 ignore the welfare of his liver or to act as if he were 
 ignorant of the laws which control it. Nevertheless, 
 many of the discoveries about these laws are so recent 
 that even well-informed people have sometimes failed 
 to hear about them. 
 
 This is true of my neighbor, who complained about 
 his liver the other day. He said the doctor advised him 
 to eat less, to exercise more, and to give up his beer un- 
 til he was in good shape again. He himself protested, 
 however. He said : " What I really need is strength, you 
 know, and how can I get strong by eating less ? As for 
 beer, so far as I can see, it is the one thing that really 
 helps me. Can't I judge by my own feelings?" The 
 doctor said he could n't, and the doctor was right. 
 Follow the argument closely. 
 
 Those of us who have ever seen a piece of raw liver 
 know how extraordinarily bloody it is. We also know 
 that it is bloody not by accident on a particular day, but 
 
GLAND LABORATORIES INFLUENCED BY ALCOHOL 175 
 
 that any piece of liver, on any day of the year, is deluged 
 with its own blood. This is inevitable because the liver 
 is always provided with an enormous number of small 
 blood vessels, each one of which is in active service. 
 
 When, therefore, the doctor gave my neighbor that 
 advice about beer, he was acting in line with his knowl- 
 edge of the effect of alcohol on blood vessels in general. 
 He knew, what we also know, that wherever there is an 
 unusual supply of capillaries and blood-carrying tubes of 
 all sizes, there will alcohol do its paralyzing work. He 
 knew that when blood vessels in the liver are somewhat 
 paralyzed and enlarged beyond their usual size, the liver 
 itself is sure to suffer in a serious way. 
 
 When a doctor examines liver after liver as he finds 
 them in the hospital and in the dissecting room, he 
 counts the ignorance of the unfortunate men no laugh- 
 ing matter. " A drunkard's liver again," he will say as 
 he opens up the telltale gland. " No wonder the man 
 died. It's a wonder he lived as long as he did with a 
 liver of this sort to purify his blood supply for him." 
 That which the doctor finds is indeed a grievous sight; 
 for a liver in the grip of alcohol is often swollen to 
 double its natural size. It has been changed from a 
 healthy, compact mass of energetic cells and tubes to 
 an inactive mass of distended tubes and of cells heavily 
 loaded with fat. In other cases the substance of the 
 gland shrivels through the effect of alcohol. 
 
176 THE BODY AT WORK 
 
 After a man's liver reaches the point where it can do 
 no more work for him, the man dies and we pity him. 
 But there are multitudes of other people who drink less 
 and suffer quite as truly. By their ignorance of the 
 
 As THE LIVER LOOKS WHEN DOING GOOD WORK 
 (After Horsley) 
 
 laws of health, and by their free choice, they are setting 
 a limit to the work which the liver may do for them. 
 In all probability, by their regular use of alcohol they 
 are slowly but steadily securing for themselves a gland 
 which grows gradually more inactive and inefficient, 
 a gland which, by its inactivity, is quietly preparing 
 them more easily to fall a prey to diseases, or to die 
 
GLAND LABORATORIES INFLUENCED BY ALCOHOL 177 
 
 earlier than they might have died. The eleventh chapter 
 of Town and City shows what insurance companies have 
 found to be the different chances of life for those who use 
 alcohol as a drink and for those who do not' so use it. 
 
 A DRUNKARD'S LIVER RUINED BY ALCOHOL 
 
 From its appearance it is sometimes called hob-nailed 
 
 (After Horsley) 
 
 Two other glands are also greatly affected by alcohol. 
 These are the kidneys. They lie on each side of the 
 lower part of the back, and their structure is a marvel- 
 ous arrangement of closely packed microscopic tubes 
 which are netted about by vast numbers of capillaries. 
 
 OF THE 
 
 ( UNIVERSITY 
 
 OF 
 
7 8 
 
 THE BODY AT WORK 
 
 The special work of the kidneys is to ricl the body of 
 many kinds of waste. This brings us round to the 
 subject of food again, and calls our attention to two 
 important focts about the disposal of waste which the 
 
 blood gathers up: 
 
 1. If we have eaten more 
 carbohydrate than we need, 
 the surplus is stored up as 
 fat and glycogen, while the 
 waste takes the shape of 
 water, and of carbon dioxid 
 gas which leaves the body 
 through the lungs. 
 
 2. If we eat more meat 
 than we need, the surplus is 
 worked over in the liver and 
 sent off as waste through 
 the kidneys. Moreover, if 
 the kidneys are overtaxed in 
 their work, they fail to clear 
 the blood entirely of its pro- 
 teid waste. This waste may 
 
 then settle in different parts of the body and result 
 
 in gout, rheumatism, and kindred ills. 
 
 Anything, therefore, that interferes with the prompt, 
 
 healthy action of the kidneys is a misfortune to us. So 
 
 true is this that many a man with kidney trouble has 
 
 THE KIDNEYS AND THE BAG 
 
 WHICH THEY SUPPLY WITH 
 
 WASTE WATER 
 
 A, artery ; B, vein ; C, tube 
 
 through which water leaves 
 
 the kidney 
 
GLAND LABORATORIES INFLUENCED BY ALCOHOL 179 
 
 been refused by insurance companies when he wished 
 to get his life insured. Such business houses know that 
 a person who has upset the power of his kidneys is a 
 " poor risk." Because of this, intelligent men listen in- 
 tently when scientists tell them that 
 alcohol has a direct effect on the 
 kidneys, and that the kidneys are 
 specially affected by weak alcoholic 
 drinks taken in large quantities. It 
 is indeed a fact recognized by all 
 doctors, that those who use beer 
 regularly, even though they drink 
 it moderately, are repeatedly found 
 to have trouble with their kidneys. 
 Not only does alcohol make the 
 capillaries of liver and kidneys in- 
 efficient, but it benumbs the work- 
 Notice the clusters of slender 
 ing pOWer Of each gland. It robs tubes; each separate one 
 
 them of their ability to be thorough- mi ^ ht be called a l "*<*y 
 going, wide-awake chemists. For this reason it is as much 
 of a calamity for these glands to receive alcohol as it 
 would be for human chemists to be made stupid by the 
 same alcohol during the time that they are carrying on 
 important investigations in a modern laboratory. 
 
 A CUT THROUGH THE 
 KIDNEY 
 
CHAPTER XXIII 
 
 HAMPERED BY CLOTHING, OR ABOVE AND BELOW 
 THE DIAPHRAGM 
 
 If you are interested in such things, study the latest 
 fashion plates for a few moments ; or, if you see fashion- 
 plate types of women on the street this afternoon, give 
 special attention to the size of their waists as compared 
 with the size of the rest of the body. If the difference 
 seems to you too great for real beauty, try to decide 
 what these women, in their ignorance, have done to 
 themselves. 
 
 I see one such woman passing at the present moment. 
 Her shoulders are broad, her hips are large, her waist 
 looks like a contracted isthmus which is doing its best 
 to hold two wide-spreading peninsulas together. Both 
 peninsulas are awkward in their movements because 
 their proper relation to the waist has been lost. They 
 rock from side to side, and the sight of the progress of 
 the woman is not attractive. 
 
 But her outward appearance is the smallest part of 
 the misfortune of her condition. She little suspects that 
 others know more about her than she would dare ac- 
 knowledge. Nevertheless, the facts are clear to those of 
 
 1 80 
 
HAMPERED BY CLOTHING 
 
 181 
 
 us who understand certain points about the structure 
 of the human machine, and we acknowledge them. 
 
 We know that this woman has something hard and 
 firm about the middle, soft part 
 of her body, and that she has 
 drawn this bandage up with such 
 vigor that, at this moment, folds 
 of crumpled flesh lie in creases 
 just underneath the whalebones 
 and the steel. We know that she 
 is most uncomfortable from the 
 pressure, but that she endures it 
 with a smiling face because she 
 thinks she has made herself more 
 slender and beautiful to look upon. 
 Her ignorance goes even further. 
 It makes her willing to do more 
 than simply rob herself of comfort. 
 
 Follow her condition down 
 through those folded rolls of flesh 
 and skin. Imagine that some new 
 kind of X-ray is ready to reveal a 
 few miserable secrets, and count 
 them up for yourself: 
 
 i. You will find yourself studying a liver, which 
 is crowded into such small compass that its capilla- 
 ries and tiny tubes are folded and pressed upon 
 
 FOR THE SAKE OF LOOKS 
 SHE LACES SLIGHTLY 
 
182 
 
 THE BODY AT WORK 
 
 each other until they labor under enormous disad- 
 vantage. This liver can neither do good work in 
 preparing glycogen from the liquid food which it 
 has received, nor thoroughly purify venous blood 
 of its waste, nor manufacture other things from this 
 
 waste. No wonder, 
 then, that the waste, 
 kept in the system, 
 is gradually giving to 
 this particular woman 
 a dull complexion. 
 Few things more 
 quickly rob a face of 
 its bright pink and 
 white than an inac- 
 tive liver. By. study- 
 ing faces and waists 
 you will have no 
 
 RIBS OF A YOUNG WOMAN WHO DIED trouble in Coming to 
 AT THE AGE OF TWENTY-THREE . > . i 
 
 the conclusion that 
 
 (After Tracy) t , , , 
 
 those who lace are 
 
 apt to be the ones who paint and powder the 
 most. Evidently they try to conceal the fact that 
 the liver is not doing full work and that the com- 
 plexion needs repairs. 
 
 2. Under the bandage the stomach endures the 
 same pressure as the liver. It has less space in 
 
HAMPERED BY CLOTHING 183 
 
 which to carry on its operations. It is consequently 
 so hampered and hindered that indigestion often 
 follows, and nothing is more fatal to a beautiful 
 complexion than the results of this condition. 
 
 3. The upper long folds of the small intestine 
 are pressed downwards. They too become inactive ; 
 food moves slowly 
 through them. The 
 disadvantage in this 
 event is that the longer 
 the food tarries on its 
 way, the more proba- 
 bility is there that it 
 will decay and produce 
 gas. Such gas is im- 
 mensely uncomfortable 
 because it stretches the 
 walls of stomach and 
 tube alike, and we feel 
 
 ,1 . , . THE SHAPE THEY SHOULD HAVE HAD 
 
 the stretching. 
 
 Lacing does not always explain the size of the abdo- 
 men, for fat often settles there as persons grow older. 
 But when a woman has persistently crowded her in- 
 testines downwards, they finally stay out of place with- 
 out the crowding. The walls of her abdomen are relaxed 
 and flabby because they have not been able to get exer- 
 cise. Everything which they inclose and which they 
 
184 
 
 THE BODY AT WORK 
 
 should hold snugly and firmly in place is left sagging 
 downwards. Each organ must therefore carry on its busi- 
 ness as best it can under most unfavorable conditions. 
 
 This we find to be 
 the state of affairs 
 below the diaphragm. 
 But what about the 
 fate of the diaphragm 
 itself ? Give attention 
 for a moment to what 
 it is and to the work 
 it does for us. 
 
 In a way it may be 
 hard to think of our- 
 selves as a double- 
 story set of apart- 
 ments, but such we 
 are. For, stretching 
 across us from side to 
 side, a little above the 
 waist line, is a strong, 
 broad, elastic parti- 
 tion of muscle called the diaphragm. Below it lie liver, 
 stomach, intestines, and other important organs. Above 
 it are the heart and lungs with the large and small 
 tubes which belong to them. Through the diaphragm 
 go several good-sized tubes, a large artery, a large 
 
 INSIDE ORGANS THAT WERE SQUEEZED 
 WHEN SHE LACED 
 
HAMPERED BY CLOTHING 185 
 
 vein, and the tube which carries food from the mouth 
 to the stomach. 
 
 Above the diaphragm, then, we find the organs of res- 
 piration and circulation, while below it lie the organs of 
 digestion and the great gland, the liver. Above the 
 diaphragm blood is ridding itself of carbon dioxid ; be- 
 low the diaphragm blood is getting supplies of nourish- 
 ment to carry to the tissues of the entire body. 
 
 But what active share does the diaphragm take in all 
 this ? Find out for yourself. Draw a deep breath. You 
 may perhaps think that you are simply expanding your 
 chest to the utmost. The truth, however, is that the 
 drawing of your breath means that you are not only 
 raising your ribs, but that you are also contracting your 
 diaphragm from every side. A healthy person in hygienic 
 clothing can prove it in this way: lay your hand on 
 your chest, and take pains that the chest shall make 
 absolutely no movement. You will find that you can 
 breathe quite well by letting the abdomen expand and 
 contract, without the least motion of the ribs. By doing 
 so you have flattened down the dome shape which it 
 usually has. When you can contract it no further, you 
 know that your lungs cannot be forced to hold more 
 air. This we call forced breathing. Through it you have 
 forced your lungs to their full size. 
 
 But natural, daily breathing is no less dependent on 
 the diaphragm. This muscle is indeed the largest and 
 
1 86 THE BODY AT WORK 
 
 the strongest breathing muscle we have. When it con- 
 tracts, air rushes into the lungs, and the upper story of 
 the body grows larger, while all that lies in the lower 
 story is exercised by the pressure of the diaphragm 
 down upon it. When again the diaphragm relaxes, the 
 pressure is lifted, air is squeezed out of the lungs, and 
 the upper cavity is smaller again. 
 
 Liver and stomach also receive decided help from 
 this rhythmic exercise, which continues throughout the 
 days and the years of our lives. And the ignorant lady 
 who laces, implies that she is ignorant by her willing- 
 ness to interfere with the healthful, regular action of her 
 tireless diaphragm. By putting pressure on her lowest 
 ribs and also on the organs contained both in her chest 
 and in her abdomen, she limits the work which her dia- 
 phragm can do not only for her lungs but also for her 
 liver and stomach and small intestine. Moreover, she 
 keeps these organs under such constant outside pres- 
 sure that they have no chance for the relaxation which 
 is also of importance to them. 
 
 Place your hands on opposite sides of your body; 
 crowd in your ribs and come to your own conclusions 
 as to what you have done to your lungs and to your 
 heart. You cannot conceal the fact that you have 
 crowded multitudes of lung cells out of service, thus 
 robbing the blood of oxygen, and that your heart is 
 pressed against by the surrounding lungs. 
 
THE DIAPHRAGM WHEN IT is RELAXED 
 The organs from above it and below it have been removed 
 
 187 
 
i88 
 
 THE BODY AT WORK 
 
 When the most important servants of the body are 
 left to the power of the foolish hands of a woman who 
 is ignorant about her own structure, and when these 
 hands give cruel treatment to servants which do her 
 hardest work for her, is it strange that rebellion follows ? 
 
 EXERCISES WHICH MAY BE TAKEN TO STRENGTHEN THE MUSCLES 
 OF THE ABDOMINAL WALL 
 
 (After Schmidt) 
 
 Is it surprising that " liver trouble," and gas, and head- 
 ache, and the blues, and unhappiness, and nervousness 
 fill the woman with lamentation? 
 
 In the face of the fashion plates and the laced-up 
 ladies, it is a curious fact that hardly ever does a 
 
HAMPERED BY CLOTHING 189 
 
 woman or a girl acknowledge that her clothes are too 
 snug for comfort or for health. She generally assures 
 us that they are really loose. 
 
 We ourselves, may of course, be exceptions ; but we 
 must remember that even slight pressure long continued 
 is harmful. 
 
 Test yourself. Stand with your back to the wall, with 
 head, heels, and elbows touching it. Draw a long, deep 
 breath. Can you do this without feeling that bands, 
 strings, buttons, or hooks are being pulled at rather 
 vigorously ? If, at the same time, you have no weight 
 of clothes dragging down on your abdomen, you may 
 count yourself as well tested. You have passed the ex- 
 amination and may congratulate yourself that you are 
 not preparing your body for defeat later in life. 
 
 If, however, you feel the pressure of something that 
 binds you, you need to make a change somewhere. 
 Bands and belts should always be large enough to allow 
 us to do our ordinary breathing without feeling that we 
 are hampered by our clothing. When we take unusual 
 exercise we breathe deeper, expanding our lungs more, 
 and our garments should be proportionately loose. 
 
 It is unwise both for growing girls and for grown 
 women to hold their skirts in place by strings drawn 
 tight about the waist. A yoke to the skirt is better, or 
 skirts may be carried by straps or by waists that hang 
 from the shoulders. In other words, weight should not 
 
190 THE BODY AT WORK 
 
 be allowed to drag down on the abdomen. Learn to 
 protect the strength and the shape of your abdominal 
 wall by putting it under such conditions as will leave it 
 firm and useful when you are grown. Remember that 
 the better you can breathe, and the more freely gland 
 laboratories are allowed to do their work, the better able 
 will you be to endure the strain of life and to resist 
 disease of every sort. 
 
 Even now, multitudes of well-informed women dress 
 according to their knowledge of these facts; and the 
 same knowledge is spreading so fast among the young, 
 that, from the signs of the times, it looks as if small, 
 deformed waists would soon be as unfashionable as are 
 the small, deformed feet of a Chinese lady. 
 
CHAPTER XXIV 
 
 FOOD OR DRINK FOR OKUSHIRI ISLANDERS 
 
 Okushiri is an island in the beautiful sea of Japan. 
 It is about fourteen miles long, and lies not far from 
 the coast of the large island of Nippon. 
 
 When the events now to be recorded took place, the 
 population of Okushiri numbered about two hundred 
 and fifty. A mere handful of. poor fishermen they 
 seemed to be, but from their obscurity and their poverty 
 they raised themselves into fame and prosperity. 
 
 In 1884 these people were distributed in four villages. 
 They lived in houses made of grass, supported them- 
 selves by fishing, had but four roads and but one school. 
 Worst of all, a famine threatened, for the price of food 
 was high, and their own catch of herring had been so 
 small that year that they had little money with which to 
 buy other kinds of food. 
 
 One thing, however, they had to comfort them in 
 their poverty. They speak of it themselves : " The people 
 have no other pleasure for body and mind than in the 
 use of sake. 1 Nine out of ten of us like the liquid, and 
 what we annually spend for the same is not small." 
 
 1 The national alcoholic drink. 
 191 
 
192 THE BODY AT WORK 
 
 To us who read about it, the amount of sake which 
 they used seems very large, for we are told that during 
 the single year of 1884 the inhabitants of Okushiri 
 imported eight hundred and eighty casks of sake for 
 their own use, and had besides a goodly stock of brandy 
 and other drinks. They intended to be well provided 
 with this one thing which consoled them in their misery 
 and helped them to forget their hunger. 
 
 Happily, however, there are as wise men in Japan as in 
 other lands. And, most happily for the fishermen, one 
 of these wise men was governor of the district of Japan 
 to which Okushiri belongs. When, therefore, this gov- 
 ernor made his regular visit to the island in 1884 and 
 saw the poverty of the people, saw that famine threat- 
 ened them for the winter, and also saw how well pre- 
 pared they were to comfort themselves with their sake, 
 their brandy, and their other drinks, he gave the sub- 
 ject close attention. 
 
 Furthermore, he made an estimate of the size of their 
 drink bill for the year, and his figures proved that they 
 were spending money, out of all proportion to what 
 they earned, on sake which did not nourish them, 
 when they were in sad need of the same money for 
 food which did nourish them. 
 
 Being a clear-headed man, he had no doubt as to 
 what should be done, and he urged the people to turn 
 the tables immediately. He begged them to provide for 
 
FOOD OR DRINK FOR OKUSHIRI ISLANDERS 193 
 
 the future by saving what they were really wasting in 
 the present. 
 
 Evidently these fisher folk had logical minds, for 
 they gave heed to his counsel. They acknowledged 
 that their debtors could not pay them what they owed, 
 that some of their own number would have to depend 
 on the government for food, and that the condition re- 
 quired an immediate, desperate remedy. Those who 
 were most deeply impressed by the situation drew up 
 a formal statement in which they said : 
 
 We are in misery, and to save ourselves from the wretched state of 
 things, we must have recourse to some extraordinary means. Frugality 
 is to be resorted to, and vanity of all sorts must be set aside. We, there- 
 fore, before all others, will abstain from the use of what we relish more 
 than all other things sake and thus close the way of importation 
 of the liquid into this island. The money we should spend for it will be 
 spent for rice and other grains, and thus we will provide for our future 
 wants on the one hand, and will increase our capital in fishery on the other. 
 
 In carrying out this determination, those who origi- 
 nated the plan drew up a formal document in order that 
 they " might secure," as they said, " the prosperity of the 
 island." They called upon all those " who like to share 
 in our privation for the good of the public and the 
 future " to " come speedily and sign the contract." This 
 was in July, 1884. 
 
 The document which the islanders were asked to 
 sign held ten different statements, which were put in 
 
194 THE BO DY AT WORK 
 
 the form of a contract. Those who signed this contract 
 pledged themselves neither to buy nor to sell alcoholic 
 liquor of any sort for five years, and to give no aid to 
 such inhabitants of Okushiri as persisted in the buying 
 or the selling of it. For any breaking of the contract 
 there was a heavy fine, and all such fines were to be 
 spent in buying rice, which should then be hoarded in a 
 common granary. Those who bought alcohol were to be 
 fined half as much as those who sold it. All immigrants 
 from other provinces were to be taught promptly about 
 the prohibition plans of the island, and no one was 
 to be admitted who did not understand the situation 
 thoroughly. Such persons as bought alcoholic liquor in 
 any form from passing ships or boats were to be taxed 
 to the full extent of the law. 
 
 Last of all, the following statement was distinctly 
 made: 
 
 This contract is to be in force for five years ; and when the provision 
 for years of scarcity is fully made and each and everybody is able to 
 lead an independent life, proper changes shall be made upon further 
 deliberation. 
 
 One hundred and seventeen Okushiri islanders signed 
 the contract. It was rigidly enforced for five years, and 
 at the end of this time still other records show what the 
 results were. 
 
 It was now 1890. Not a drunkard was left on the 
 island. Some had been reformed by giving up the 
 
FOOD OR DRINK FOR OKUSHIRI ISLANDERS 195 
 
 drinking habit. Others who were too weak to change 
 had gone elsewhere to live. Those who stayed had pros- 
 pered greatly, while their numbers had increased five- 
 fold. The money which they had put into the fishing 
 industry had multiplied itself by ten. They had even 
 started a new line of work, for now they raised their own 
 hemp and made their own fish nets. Their houses were 
 larger and better made, their schools had improved in 
 quality and in numbers, additional roads had been con- 
 structed, and there was less crime. From being spoken 
 of with pity by neighboring islands, as was previously 
 the case, these fishermen were now referred to as " the 
 prosperous people of Okushiri." 
 
 The five years had certainly brought good results. 
 Okushiri islanders were no longer a poor and miser- 
 able people. Famine did not threaten them now. Was 
 it necessary, then, to keep sake and brandy out of the 
 island any longer? This was the great question of the 
 day for Okushiri in 1890. They discussed it thoroughly 
 and answered it by deciding that for still another stretch 
 of five years they would travel by the road which had led 
 them to such happy results. According to last reports 
 they were still going without alcohol and were still 
 prospering. 
 
 In other lands those who are interested in the ques- 
 tion of profit and loss have asked themselves whether or 
 not it is a good investment to put money into daily 
 
196 THE BODY AT WORK 
 
 drinks of beer. They have looked into the matter quite 
 as thoroughly as did the governor of Okushiri, and have 
 come upon a striking set of facts. By making careful 
 inquiry about prevailing prices in America in 1908, they 
 found that if a person should drink three glasses of beer 
 a day during one year, he would spend, on this drink 
 alone, enough to buy the following articles. They are 
 placed one under the other, that they may be read easily. 
 
 i barrel of flour 
 50 pounds of sugar 
 20 pounds of cornstarch 
 10 pounds of macaroni 
 10 quarts of beans 
 
 4 twelve-pound hams 
 
 i bushel sweet potatoes 
 3 bushels Irish potatoes 
 10 pounds of coffee 
 i o pounds of raisins 
 i o pounds of rice 
 20 pounds of crackers 
 100 bars of soap 
 
 3 twelve-pound turkeys 
 
 5 quarts of cranberries 
 10 bunches of celery 
 10 pounds of prunes 
 
 4 dozen oranges 
 
 i o pounds of mixed nuts 
 3 tons of coal at five dollars a ton 
 
CHAPTER XXV 
 
 THAT WHICH DESTROYS, AND HOW MEN SAVE 
 THEMSELVES 
 
 On the eighteenth of December, 1902, in the city of 
 Paris, France, a report was made by a committee of the 
 government. The state officials considered this report so 
 valuable that they ordered copies of it printed as posters 
 in large black letters on a white background. In France 
 none but state officials are allowed to print posters thus 
 in black and white. When such appear, therefore, they 
 are read, because they come from the government. 
 
 These posters were placarded here and there on the 
 important buildings of the city. They were put on the 
 walls and in the corridors of hospitals, on the streets, in 
 the post offices, and even on the outside wall of the great 
 Hotel de Ville, where the business of the city is carried on. 
 
 A few extracts will show what it was that the govern- 
 ment wished to proclaim in this public way. 
 
 DRAFTED BY 
 
 PROFESSOR DEBOVE, Dean of the Faculty of Medicine, 
 DR. FAISANS, Physician to the Hotel Dieu. 
 
 Alcoholism is chronic poisoning resulting from the habitual use of 
 alcohol, even when this is not taken in amounts sufficient to produce 
 
 197 
 
198 THE BODY AT WORK 
 
 drunkenness. Alcohol is useful to nobody, it is harmful to all. It leads, 
 at the very least, to the hospital, for alcoholism causes a great variety 
 of diseases, many of them most deadly. It is one of the most frequent 
 causes of consumption. Typhoid fever, pneumonia, or erysipelas, which 
 would be mild in a sober individual, will rapidly kill the alcoholic. 
 Alcoholism is one of the most frightful scourges, whether it be regarded 
 from the point of view of the health of the individual, of the existence 
 of the family, or of the future of the country. 
 
 Paris does not stand alone in this protest against alco- 
 hol. Through the recent revelations of science every 
 country is roused at last. The most ambitious nations 
 recognize the fact that they themselves are strong or 
 weak in proportion as their individual citizens have 
 strong or weak bodies. 
 
 This, then, explains the activity against alcohol which 
 appears in many lands. Anti-alcohol leagues and socie- 
 ties comprise tens of thousands of men and women 
 who know that alcohol is more dangerous than fire as 
 a plaything. " Let a man know the facts," they say, 
 "and if he is wise he will no more risk his life by drink- 
 ing alcohol than by jumping into a burning building." 
 These societies, therefore, do their work by printing 
 and distributing facts about the effects of alcohol on 
 body, mind, and character. And the material which 
 they have gathered covers thousands of pages. 
 
 In Germany alone, previous to 1908, eight hundred 
 and seventy-one books were printed which discussed 
 
THAT WHICH DESTROYS 199 
 
 the question of alcohol. Thirty-seven newspapers, maga- 
 zines, and annuals devoted themselves to the same sub- 
 ject ; and hundreds of articles about alcohol were printed 
 in the important magazines of that country. 
 
 The prominent men in this great German movement 
 are the professors of physiology in German universities. 
 Indeed, the matter has gone so far in Germany that, in 
 1907 one hundred leading professors in the leading uni- 
 versities, signed a declaration which included the follow- 
 ing statements : 
 
 All the prevalent ideas in regard to the invigorating and otherwise 
 supposedly beneficial properties of alcohol in small doses have been 
 proved erroneous by scientific research. Moderate drinking has a 
 tendency to make the human body more liable to disease and to 
 shorten life. 
 
 The Imperial Health Office in Berlin is sending out 
 arguments against using alcohol as a drink; and the 
 brother-in-law of the emperor, Count Douglas, is one of 
 the most earnest workers in the anti-alcohol campaign. 
 Many of these men in Germany advocate going with- 
 out alcohol entirely. They say, " The abstainer alone is 
 doing his duty." 
 
 In Sweden the royal family is noted for the number 
 of those who practice total abstinence. It was the 
 crown prince himself who gave the address of welcome 
 to the great temperance gathering that met in Stock- 
 holm in 1907. 
 
200 THE BODY AT WORK 
 
 In Japan the law of the land forbids the sale of 
 alcoholic drinks to those who are under twenty years 
 of age. 
 
 In the United States, in 1908, over thirty-six million 
 people in different cities, districts, and states were living 
 under laws which prohibit the sale of alcohol in their 
 neighborhood. The people themselves have made these 
 laws for their own protection. Sometimes, however, 
 there is great excitement, with danger of defeat. This 
 was true for Indian Territory in 1905 ; and the history 
 of the struggle is a sequel to the twenty-seventh chapter 
 of Town and City. It continues the tale of the rela- 
 tion of America to the Indians and to their protection 
 against alcohol. 
 
 For seventy-two years the government of the United 
 States kept its promise to the Five Civilized Tribes, 
 and without alcohol the Indians prospered so well that 
 it did not occur to them that they could ever again be 
 in danger from intoxicating liquors sold in public. But 
 in course of time there was danger, and it came about 
 in this way. 
 
 The great event for every territory in America is 
 when it can count up inhabitants enough to allow it to 
 be changed from a territory to a state ; for when this 
 time arrives it may send senators and representatives to 
 Congress, and may do its part in governing the entire 
 country as well as itself. Before this day dawns each 
 
THAT WHICH DESTROYS 2OI 
 
 territory is treated as a child and governed from head- 
 quarters in Washington. We see, then, why a territory 
 is about as proud to become a state and a voter as a 
 boy is to become a man and a voter. Yet it was this 
 very chance to be a state that brought the danger to 
 Indian Territory in 1905. 
 
 For some time there had been talk about changing 
 three western territories New Mexico, Oklahoma, and 
 Indian Territory into states; and at last it looked as 
 if Congress would do it. Naturally, of course, everything 
 that is said or written at such a time is carefully fol- 
 lowed by those who are specially interested. We may 
 then imagine the astonishment, even the terror, of the 
 Indians, when they saw that according to the proposals 
 that were being made, the government was likely to 
 give up all responsibility in the matter of prohibiting 
 the sale of alcohol in their territory. In which case, after 
 Indian Territory should become a state, any liquor dealer 
 in the land would be quite at liberty to carry on his 
 business there. 
 
 Not alone Indians, but white residents of Indian 
 Territory as well, were ready to protest against this. 
 They had gone to the place to be rid of the crime 
 and the taxes that liquor brings, and were not at all in- 
 clined to give up their freedom without a struggle. 
 
 But the situation was even worse than at first ap- 
 peared. Look at a map of the United States and notice 
 
202 THE BODY AT WORK 
 
 that Texas is south of Indian Territory and Arkansas 
 east of it. Now both of these states had already voted 
 saloons out of more than two thirds of their area. Be- 
 sides this, other states north and east were also crowd- 
 ing saloons out of one district after another. The result 
 was that thousands of those who wished to sell alcohol 
 and thousands of those who wished to buy it had been 
 forced out of business and were eagerly ready for the 
 new opening. 
 
 The inhabitants of Indian Territory were convinced 
 that if the government of the United States should 
 cease to protect them from alcoholic drinks, many dis- 
 lodged and undesirable citizens from elsewhere would 
 crowd in like famished wolves and would try to com- 
 pensate themselves for having been thrust out of other 
 places. For this purpose, indeed, unscrupulous men were 
 using their money and their influence to try to induce 
 the United States Senate to break its promise. They 
 were ready to sacrifice even the honor of their country 
 for the sake of getting alcohol into the new state. 
 
 There was still another party at work, however. Nor 
 was this strange, for when a great calamity threatens to 
 overwhelm a people, all good citizens are ready to join 
 hands for the rescue. Indians now held meetings and 
 conferences. They worked and protested. Their white 
 fellow-citizens sent delegates to talk with senators and 
 with different members of important committees in 
 
THAT WHICH DESTROYS 203 
 
 Washington. They kept the country informed as to 
 what the danger was and how things were going. They 
 let certain suspected senators know that if they should 
 betray the government by voting to break its solemn 
 promise, the honest people of the entire country would 
 be outraged and would do all they could to prevent 
 them from being sent to Congress again. 
 
 Among the senators themselves there were those who 
 said that rather than have the government disgrace 
 itself by a broken promise of this sort, they would vote 
 against having Indian Territory become a state at all. 
 In which case, the prohibition laws would stay as they 
 had been. 
 
 The agitation lasted for two years. Then the senators 
 did what was honest. They even made that part of the 
 country safer than before, for they joined Indian Terri- 
 tory to Oklahoma, gave the name Oklahoma to the 
 new state, and enacted a temperance law which will do 
 its part in saving Oklahoma from alcohol. The follow- 
 ing words are taken from the new law: 
 
 The manufacture, sale, barter, and giving away of intoxicating liquors 
 within this state is hereby prohibited for a period of twenty-one years 
 after the date of the admission of this state into the Union, and there- 
 after until the people of this state shall otherwise provide by amend- 
 ment of this constitution. 
 
CHAPTER XXVI 
 
 PROTECTED BY THE SKIN 
 
 There is no doubt about the value of the work which 
 certain scientists did in 1775. These men were anxious 
 to know how much heat the body of man can endure 
 and still keep at its work. For the sake of making no 
 great blunder, they began their tests by passing from 
 one heated room to another until they found themselves 
 living and breathing in a room in which the thermome- 
 ter showed a heat of 210 F. 1 This is but two degrees 
 cooler than the temperature which water needs for 
 boiling. 
 
 As may be imagined, the air of the room felt very 
 hot. One man, however, stayed in it for ten minutes. 
 During this time the heat was so great that it twisted 
 and broke the ivory frames of all the thermometers but 
 one. More than this, the air which the man inhaled was 
 so much hotter than that which he exhaled, that, with 
 each breath which he drew, he felt as if he were scorch- 
 ing his nostrils. But with each exhalation his nostrils 
 were cooled again. He took the thermometer in his 
 hand and blew on it. At once the mercury sank in the 
 
 1 Fahrenheit. 
 204 
 
PROTECTED BY THE SKIN 205 
 
 tube, showing that his breath was cooler than the room. 
 He blew on his fingers and they were cooled too. 
 
 In another experiment afterwards, the same men went 
 into a small room which was even hotter than any 
 they had been in before. Here the thermometer showed 
 260 F. This, then, was forty-eight degrees hotter than 
 water needs for boiling. As they entered, the air felt 
 hot but they could bear it. And while they stayed 
 there they did various things to show what the heat of 
 the room was able to accomplish. They took a piece of 
 raw beefsteak, left it uncovered, took a pair of bellows, 
 blew the heated air across the steak for thirteen minutes, 
 and found that it was rather overcooked. An egg was 
 roasted hard in twenty minutes ; water soon boiled and 
 bubbled; watch chains became too hot to be touched; 
 and rings had to be left off, lest the heated metal should 
 burn a deep circle about the tender flesh of the finger. 
 Leather shoes could not be worn, for the leather itself 
 curled up and was ruined. 
 
 All this happened to their possessions, but the men 
 themselves, although surrounded by the same heated air, 
 were neither boiled nor roasted. They lived and breathed 
 in the place, escaped alive, and their escape was no 
 miracle. It was explained by the power of the sweat 
 glands. If these small laboratories had stayed inactive, 
 the scientists might have suffered from the heat even as 
 did the steak. But their glands were able to save them. 
 
2O6 
 
 THE BODY AT WORK 
 
 As soon as the men entered the heated room the 
 sweat glands began their work; perspiration was manu- 
 factured in quantities; it poured from the open flues of 
 countless small laboratories and emptied itself upon the 
 skin, whence it was evaporated. Thus perspiration kept 
 the skin moist, and the evaporation of 
 the moisture kept the surface of the body 
 cool enough to save it from being cooked. 
 Certainly the men were uncomfortable 
 from first to last, but they did not suffer. 
 The record of these experiments is 
 given in the Philosophical Transactions 
 of the Royal Society of London for the 
 year 1775. 
 
 If you ever have the chance, watch 
 the streaming, steaming backs of such 
 men as pitch coal into the huge furnace 
 of an ocean liner. There you will see the 
 same work of protection carried on by 
 
 A SWEAT GLAND . ' 
 
 AND ITS OUTLET these tireless glands. Their exact number 
 ON THE SKIN jg un k nowri) but by counting a few, in a 
 small area of the skin, and by multiplying this number 
 by the extent of the surface of the body, men estimate 
 that each of us is supplied with about two million sweat- 
 gland laboratories. All are slightly busy most of the 
 time, but only extraordinarily busy when emergencies 
 overtake the body. 
 
PROTECTED BY THE SKIN 207 
 
 Just here review your knowledge of the skin and of 
 perspiration as learned in Good Health : 
 
 1. The outside layer of the skin is called epider- 
 mis. It can be cut or pricked without giving pain. 
 It protects all that lies underneath it, in the second 
 layer of the skin. 
 
 2. The second layer the dermis holds capil- 
 laries, nerve fibers, hair cells with their muscles and 
 oil glands, sweat glands, and pigment cells. These 
 last contain coloring matter pigment which 
 gives one boy freckles and another boy tan ; which 
 makes one man brown and another man yellow. 
 Both nails and hair are constantly being formed in 
 the dermis and pushed upward. 1 
 
 3. Perspiration is a mixture of water and waste. 
 It is poured out by the sweat glands when the body 
 is heated or exercised. The water soon evaporates 
 and cools the skin. The waste stays on the skin 
 and must be washed or rubbed off; otherwise it 
 mixes with oil from the oil glands, with bits of epi- 
 dermis, with dust from the clothes and from the air, 
 and stays like a snug, thin, perfectly fitting coat on 
 the outside of the body from head to heel. A thick 
 wrap of this sort interferes with the healthy action 
 of the skin, and gives off an unpleasant smell. It 
 may be removed by a hard, dry rub, and it is 
 
 1 Full directions about the care of both are given in Good Health. 
 
208 
 
 THE BODY AT WORK 
 
 important to take the rub when- 
 ever a bath is out of the question. 
 
 Since the skin is so well provided 
 with blood vessels, it is natural that 
 small wounds should heal quickly. 
 Even when a patch of skin is entirely 
 destroyed by being scalded or burned, 
 there is such power of life left along 
 the edges, that new skin grows out 
 from it day by day until the chasm 
 is entirely covered. 
 
 But there is a limit to what can 
 be done in this direction, and at such 
 times doctors step in with their won- 
 derful help from grafted skin. 
 
 For each of us, however, there is 
 something far more important than 
 hot ovens, burned flesh, and the graft- 
 ing of- the skin. It is not probable 
 that we ourselves shall meet these 
 A, homy layer of epider- terrible experiences. But a very prac- 
 
 mis; B, deeper layer of . . 
 
 epidermis; c, duct of tical, everyday danger is always at 
 
 sweat gland; D dermis ; ^^ WQ may take cold through OUr 
 J5, connective tissue in * 
 
 which the black lines rep- ignorance of the laws of skin health 
 
 resent blood vessels . . T . . 
 
 and vigor. Let us therefore remember 
 that the skin is constantly covered with a slight mois- 
 ture called insensible perspiration, and that when there is 
 
 CUT THROUGH THE 
 LAYERS OF THE SKIN 
 
PROTECTED BY THE SKIN 209 
 
 enough of this moisture to be noticed it is called sensible 
 perspiration. The purpose of perspiration is to cool the 
 body whenever it is in danger of getting overheated. 
 For the sake of grasping the situation more clearly, bear 
 the following facts in mind : 
 
 1. When a man is heated from exercise, capillaries 
 in the exercised part of the body are stretched out 
 with the blood which is forced into them. 
 
 2. If a heated man, covered with perspiration, sits 
 in a draft, his blood is cooled, the capillaries of the 
 skin contract, and the mass of the blood goes to 
 some other place. 
 
 3. When this occurs, the linings of nose, throat, 
 lungs, and intestines are apt to be overcrowded by 
 the blood which has been forced into them from the 
 skin, and the most sensitive lining suffers most. 
 
 Usually the first symptom of a cold is that a man 
 feels stuffy in nose, throat, or lungs. The explanation of 
 the feeling is the distended capillaries, with another fact 
 added. Although red corpuscles continue to deal with 
 oxygen as they have always done, still the white corpus- 
 cles are now behaving strangely. They get together, 
 many of them stick to the inside walls all along the 
 length of the capillaries, and the more inactive they are, 
 the less do they seize and destroy intruding microbes. 
 These microbes, therefore, remain in the blood and con- 
 tinue such mischief as their nature makes possible. 
 
210 THE BODY AT WORK 
 
 When a man has a cold the trouble often is that- in- 
 fluenza microbes have escaped the white corpuscles and 
 have firmly established themselves in the part of the 
 body which is congested with blood. 
 
 In view of these facts it is not hard to understand 
 why a man who has a cold is so much more liable to 
 take other diseases to which he is exposed. He is in 
 a weakened condition, and already microbes instead of 
 white corpuscles have the upper hand. 
 
 But suppose a cold is coming on, what does our knowl- 
 edge of the laws of the skin direct us to do about it ? 
 
 Draw blood away from the region of the cold as 
 promptly as possible. Do it in several ways: take 
 vigorous exercise until every sweat gland is active ; 
 take a hot bath; soak the feet in hot water; drink 
 hot lemonade; go to bed; sleep warm; perspire freely. 
 By keeping warm in bed the blood goes to the surface 
 of the body, and delicate internal membranes are re- 
 lieved of superfluous blood. White corpuscles are also 
 stirred up, and restoration begins. Stay in bed until the 
 feeling of cold is over. One night may suffice. When 
 you leave the bed be specially careful to avoid every 
 chance draft, for a draft just now will undo the good 
 results of the heat treatment. Take a warm bath at 
 once, then a quick wash with cool water. This will 
 stimulate the nerves of your skin without chilling the 
 blood itself, and keep you from taking cold afterwards. 
 
PROTECTED BY THE SKIN 2 1 1 
 
 If going to bed is out of the question, dress more 
 warmly than usual, keep out of drafts, observe every law 
 of general health, and determine to be strictly careful 
 not to expose yourself to colds in the future. 
 
 Sitting in drafts or with damp feet, or with clothes 
 damp from perspiration or from rain, is dangerous be- 
 cause in these ways the body may be chilled. A quick, 
 cold, two-minute bath with a hard rub afterwards acts 
 as a tonic and not as a chill to the body. 
 
CHAPTER XXVII 
 
 WORK, HEAT, AND FUEL 
 
 Let a man live in central Africa or let him travel 
 to the coldest land; let him stay in the burning heat 
 of his city home or wander in the cool shadows of 
 the country; let him be in bed or in the harvest field, 
 in the countinghouse or in the mine ; wherever he is, 
 he will find that if he is well the thermometer under 
 his tongue always indicates about ninety-eight degrees 
 of temperature. 
 
 In each place also, even if he is not well, the heat of 
 his body will change but little. We say that a man has 
 a slight fever if his temperature is 100 F. If it reaches 
 102 we grow somewhat troubled ; if it rises to 103 and 
 then to 104, we are truly anxious ; for no man is expected 
 to live after his temperature has reached a higher point 
 than 107. 
 
 It is well for us that the body has this power to keep 
 the blood warm independent of outside conditions; for 
 if it were otherwise, if we were as cold-blooded as is 
 the frog, we should be as useless in cold weather and 
 in cold places as he is. We should have to hibernate 
 in winter as he does. 
 
 212 
 
WORK, HEAT, AND FUEL 213 
 
 Birds, as well as all animals that begin life by taking 
 milk from their parents mammals they are called are 
 warm-blooded. Each has for itself this wonderful power 
 of meeting the changes of the weather with a constant 
 temperature of its own. As a result, such animals are 
 generally warmer than the surrounding air, and are called 
 warm-blooded for this reason. 
 
 Cold-blooded creatures usually feel cold to the hand 
 when we, who are warm-blooded, touch them. Their 
 bodies have no power to stay warm when the air is 
 cold about them. 
 
 Although this power is part of our possession, it is 
 nevertheless true that even the heat of our warm bodies 
 can fail. Men do freeze to death. They cannot endure 
 a freeze and then slowly come out of it, as does a cold- 
 blooded animal. People may live in the coldest countries 
 and be active and healthy there, but the one condition is 
 that they help the body do its work by preventing the 
 escape of more heat than the same body can promptly 
 replace. 
 
 Never confuse these two facts : 
 
 1. The inside heat of the body changes little from 
 year's end to year's end. If it changes many degrees 
 up or down, we die. 
 
 2. The skin feels warm or cold as the air about it 
 changes. Skin and nose and toes may freeze, but the 
 inside temperature remains practically unchanged. 
 
214 THE BODY AT WORK 
 
 Put a dozen people in a small room, and the room 
 grows warmer because those human beings give off 
 enough heat to warm the air about them. In a cold 
 country or in a cold room each body must keep within 
 itself as much of its own heat as it can. Naturally, 
 therefore, we wear more clothes at one time than at 
 another. We are treasuring up our own supply of heat 
 for our own use. 
 
 In the same matter of heat we may ask why exercise 
 helps. Why do boys say, " It 's so cold we 've got to run 
 to keep warm ? " For the mere reason that when muscles 
 contract and when blood moves fast, the heat of the body 
 is decidedly increased. Any one who can get hold of a 
 doctor's thermometer may test this for himself. Put it 
 far back under your tongue and keep it there two min- 
 utes ; decide what your present temperature is, then take 
 vigorous exercise of one sort or another for twenty min- 
 utes and use the thermometer again. If you did not 
 breathe through your mouth, you may find that you 
 have been able to raise your temperature slightly. 
 
 Consider also that while you exercised and breathed 
 hard you expelled quantities of warmed air from your 
 lungs. Without doubt, then, taken altogether, your body 
 produced a large amount of heat while it also worked. 
 Now try to explain the source of its power to do these 
 two things. Watch yourself at the dinner table after exer- 
 cising. You have such an appetite as comes only when 
 
WORK, HEAT, AND FUEL 215 
 
 you have been using up your supplies. Food is to the 
 body what fuel is to a stove, and in a certain way your 
 machine has been burning up its fuel while you worked 
 and grew warm. Your appetite is nature's call for a fresh 
 supply of food. 
 
 Sometimes active exercise leads the body to call for 
 so much fuel that the stored-up supply, fat, is rapidly 
 reduced. Talk this over with any thoughtful football 
 player and he will tell you that during the football sea- 
 son he loses much of the fat which was stored up by 
 the body during the previous summer. The body has 
 need of extra fuel when it does unusual work, and it 
 then draws on its reserved supply. 
 
 A fat man applies this power of the body to his own 
 case. He studies himself both in the mirror and on the 
 scales, and concludes that his body has stored up too 
 much fuel in the shape of fat. He knows that to get rid 
 of it he must compel his muscles to use it, and at once 
 he begins a course of vigorous exercise which gives hard 
 work to large muscles. They respond by calling for fuel, 
 and if he is faithful day after day, the mirror and the 
 scales will soon show that he is accomplishing his pur- 
 pose, that he is losing his fat. 
 
 Perhaps we wonder how it happens that although we 
 sometimes exercise so hard as to use up much of our 
 fuel, the thermometer shows a gain of so little bodily 
 heat. As we learned in the last chapter, the reason 
 
2i6 THE BODY AT WORK 
 
 rests with the sweat glands. They are such a success- 
 ful cooling device that whenever we exercise enough 
 to raise our temperature above its normal point, they 
 promptly manufacture their clear-colored liquid and 
 send so much of it out upon the skin that the internal 
 temperature of the body is kept from rising too high 
 for safety. 
 
 The body is thus seen to produce its own heat, while 
 it also cools itself when we overheat it. Through this 
 power, however, we may take cold unless we know how 
 to prevent heat from escaping too fast when the body 
 needs it. Three rules will be useful in putting this into 
 practice : 
 
 1. Never sit long in a room that feels chilly. A 
 long, slow chilling of the body does even more 
 harm than a draft. 
 
 2. Never come in heated from hard exercise and 
 cool off in a chilly room. Either continue exercise 
 in the room, or wrap up thoroughly. Best of all, 
 when this is possible, take a quick cool bath and 
 change your damp underwear before you sit down 
 for quiet work. 
 
 3. Remember that there is little danger of harm 
 to health, however damp the clothing may be, so 
 long as vigorous exercise is kept up. 
 
 Whether our garments are damp or dry, however, it is 
 always true that we are warmed not by the cold we keep 
 
WORK, HEAT, AND FUEL 2 1 7 
 
 out but by the heat we keep in. 1 Flannel succeeds 
 better than cotton in preventing the escape of heat, 
 because more air is entangled in the mesh of woolen 
 than in that of cotton goods, and air is a poor con- 
 ductor of heat. For this reason we choose woolen goods 
 for winter wear and cotton materials for our summer 
 clothing. 
 
 During a long drive in the face of a sharp wind 
 many a sensible man has slipped a newspaper under his 
 coat. He has acted on his knowledge of the fact that a 
 layer of air is under each layer of paper, and that the 
 more layers of paper and air he has near his body the 
 warmer will they keep him. In summer, on the other 
 hand, we choose the thinnest muslin and the fewest 
 possible layers of it. We wish to make it easy for the 
 heat to escape. 
 
 That which we may do in guiding or in preventing 
 the loss of bodily heat leads us to our knowledge of 
 another fact : We may so train the body that it will im- 
 prove in the power to adjust itself to -different states 'of 
 heat and cold. In other words, the body can be educated. 
 
 1 If the body is not sufficiently covered, heat radiates from it and a cool layer 
 of air finally surrounds it. Because of this cold layer the blood vessels of the skin 
 now contract and force the blood away from the surface to the inward parts of 
 the body. These parts then become congested, while the skin feels cold, because 
 the contracted blood vessels can only hold a small supply of blood. By putting 
 on extra clothing at such times and by rubbing ourselves hard, we cause the 
 blood vessels of the skin to expand, more blood passes through them, and we 
 are warm again. 
 
2l8 THE BODY AT WORK 
 
 This may be done by following the rules already given 
 and by attending to a few other points: 
 
 1. Do not spend much time in overheated rooms, 
 that is, in places heated above 70 F. The body 
 grows exceedingly sensitive to cold if it is kept 
 constantly too warm. 
 
 2. Do not overweight yourself with clothing in 
 a warm house, nor take vigorous exercise in heavy 
 garments. In other words, regulate your clothes to 
 your need. 
 
 3. If you are in good health, take a quick cold 
 bath every morning. Nothing is better for preparing 
 the blood vessels for changes in temperature. 
 
 4. Keep the body clean by a soap-and-water 
 bath at least once a week. 
 
 He who attends to the various rules connected with 
 bathing, eating, exercise, and the heating of the body 
 will find, at last, that he has reached the happy condition 
 where sudden changes in temperature and unexpected 
 drafts do not harm him as they did in former days. 
 
 The great work of hygiene is to help the body as it 
 tries to help itself. 
 
BIBLIOGRAPHICAL LIST 
 
 HOWELL, W. H., A Text-Book of Physiology for Medical Students and Physi- 
 
 cians. 1907. 
 
 HOUGH, THEODORE, and SEDGWICK, W. T., The Human Mechanism. 1906. 
 LANDOIS, L., and STERLING, WILLIAM, A Text-Book of Human Physiology. 
 
 CANNON, W. B., The Movements of the Stomach studied by Means of the 
 
 Rontgen Rays. Article in The American Journal of Physiology. Vol. I. 
 CANNON, W. B., The Movements of the Intestines studied by Means of the 
 
 Rontgen Rays. Article in The American Journal of Physiology. Vol. VI. 
 CHITTENDEN, R. H., The Nutrition of Man. 1907. 
 CUTTEN, G. B., The Psychology of Alcoholism. 1907. 
 GULICK, L. H., Physical Education by Muscular Exercise. 1904. 
 GULICK, L. H., The Efficient Life. 1907. 
 HARVEY, WILLIAM, Anatomical Disquisition on the Motion of the Heart 
 
 and Blood in Animals. Written in 1628. Translated from the Latin by 
 
 Robert Willis. 
 HORSLEY, SIR VICTOR, and STURGE, MARY D., Alcohol and the Human 
 
 Body. 1907. 
 
 RAVENHILL, ALICE, Lessons in Practical Hygiene. 1907. 
 SARGENT, DUDLEY A., Health, Strength, and Power. 1904. 
 SCHMIDT, FERDINAND AUGUST, Unser Korper. 1903. 
 
 219 
 
QUESTIONS 
 
 CHAPTER I 
 
 How do some cities get the records of a man ? Which gives the best 
 record, a photograph or the measurements of certain bones ? After what 
 age are bones set for life ? Why does a nurse support the head and 
 back of a young baby ? How do Indian mothers secure flat heads for 
 their children ? Describe the case of the baby who always slept with his 
 face turned the same way on his pillow. If his mother had done nothing 
 about it, what would have been the result ? Give two laws of bone 
 growth. Describe the appearance of the boy who failed to get work. 
 Describe the boy who secured work. In what ways does the body tell 
 facts about us ? How much responsibility have we for the bodies we 
 live in ? 
 
 CHAPTER II 
 
 Were you satisfied or dissatisfied with the examination of your own 
 body ? What points did you decide to change ? Mention some objec- 
 tionable positions to take when seated. Tell why each is objectionable. 
 What difference is there between sitting with a twist in the back once in 
 a while and taking the same position most of the time ? What must be 
 guarded against ? Was it the older or the younger girls in the German 
 school that had most trouble from lateral curvature of the spine ? Why 
 was this ? Mention other countries where school children have the same 
 curves. Where, when, and how do children get these curves ? Why are 
 gymnastic exercises put between recitations ? Mention various positions 
 that bring curves to the spine. What objection is there to these curves ? 
 
 221 
 
222 THE BODY AT WORK 
 
 If the medical inspector finds that you have wrong curves, what will you 
 do about it ? Give four laws of prevention. 
 
 CHAPTER III 
 
 Mention the case of the strong, bent back and tell how it was secured. 
 Why do certain bicycle riders have bent backs ? What law explains the 
 strong but bent back ? How did a traveling man lower his shoulder ? 
 Describe the backs of two oarsmen, and tell why one is curved and the 
 other straight even when they walk. Why does the hand of a piano 
 player stay open even when he is not playing ? Why do the fingers 
 of an oarsman curl up even when he is not rowing ? Mention such 
 occupations as you think may change the shape of the body. Why is the 
 body thus changed ? Give the second great law about muscles stretching 
 and contracting. How may a man who works in a bent position save 
 himself from the evil effects of his work ? Give such examples as you 
 can call to mind. 
 
 CHAPTER IV 
 
 What did the doctor tell his audience they could do with their bodies ? 
 How did the student show what the muscles can do ? How did his back 
 and arms look before he forced the muscles into action ? What was it 
 that raised bunches here and there a moment later ? How could muscles 
 be pulled up so short and hard without the use of apparatus ? What did 
 the man pull against ? Was the work done best with or without close 
 attention ? What did the lecturer say about the way to develop muscles 
 without apparatus ? How often and for how long a time should the 
 exercises be taken ? How much change did the student say he had 
 made in the size of his own arm within one month ? What should be 
 done to make a close examination of the structure of a muscle ? What 
 is a muscle fiber ? What can you say about the size and the shape of 
 different muscles ? How is each formed ? What is the sarcolemma ? 
 
QUESTIONS 223 
 
 Where is the connective tissue ? What lies within the connective tissue ? 
 Of what use are the fine threads of connective tissues that stretch away 
 from the ends of muscle fibers ? What do they help form ? How do you 
 explain the difference between tough and tender meat ? Why is a spring 
 chicken tender ? How can you toughen your own muscle ? Describe 
 voluntary muscles. What is the work of involuntary muscles ? How 
 much do the muscles as a whole weigh ? Can you mention the name of 
 any muscle ? 
 
 CHAPTER V 
 
 In what way do bones help muscles ? How do muscles and tendons 
 help bones ? Describe the outside of a fresh bone. Describe the inside 
 of a fresh bone. What is the advantage in having bones made in this 
 way ? What would a magnifying glass show ? What two things can a 
 chemist do to a bone ? What good thing does a cook get from a bone ? 
 What are the two important substances which together form bone ? 
 Why should aged people be careful not to fall ? Why do their bones 
 break more easily than those of children? Why are young bones 
 pliable ? If, being young, you wish to change the shape of your chest, 
 how will you do it? Which has the most bones, a man or a baby? 
 Describe the shape of different bones. How many are there in a human 
 being ? What is a vertebra ? How many vertebrae are there ? How are 
 they held together ? Explain how vertebrae may become wedge-shaped. 
 What effect does hard work have on the bones ? 
 
 CHAPTER VI 
 
 Describe the small foot of a Chinese lady. How was it secured? 
 How useful was it ? How many bones are there in the foot ? How are 
 they joined to each other? In order to have the foot in thoroughly 
 good condition and as useful as possible, how much freedom should the 
 muscles, bones, and tendons have ? Which is most desirable, the flat or 
 
224 THE BODY AT WORK 
 
 the arched foot ? How can you decide which kind you have ? If you 
 have a tendency to flat feet, how can you help yourself ? Why should 
 feet be uncramped ? What explains the ruined shape of many feet ? In 
 buying shoes, what points should be kept in mind ? Why are tight gar- 
 ters objectionable ? 
 
 CHAPTER VII 
 
 What happened to Alice, the elephant ? Why is it often worse to 
 sprain an ankle than to break a bone ? What fastens a muscle to a 
 bone ? Just how does a muscle help move a bone ? Where is the con- 
 tracting done, in muscle or tendon ? What sometimes occurs to the 
 bone when a tendon is badly strained ? What connection is there 
 between joints and the direction which bones shall take ? Describe the 
 joints which lie between the skull and the spine. Where do we find 
 important ball-and-socket joints? What sort of joint is there at the 
 knee ? What is the difference between tendon and ligament ? What is 
 it that holds bones to each other ? Name two kinds of joints. Where 
 do you find examples of each ? 
 
 CHAPTER VIII 
 
 In what ways do boys in some cities get their exercise ? Of what 
 advantage is this exercise ? How does it happen that more attention is 
 paid to the health of children to-day than ever before in the history of 
 the world ? What is the object of the Public Schools Athletic League in 
 New York City ? Tell what you can about the way it is carried on. How 
 does the victory of a single boy mean victory for his school ? What do 
 the best athletic trainers of the country say about the use of alcohol and 
 tobacco by their men ? What part of the body does tobacco harm the 
 most ? What is the usual record, on the athletic field and in the class 
 room, of those who habitually use cigarettes ? Why has the American 
 army often refused men who wished to join it as soldiers ? Why 
 
QUESTIONS 225 
 
 should men with weak hearts keep out of the army? What did Mr. 
 Me Bride say about the use of tobacco and alcohol by football players at 
 Yale ? What does Mr. Edwards say for the Princeton team ? What does 
 Mr. Stagg say ? What does Mr. Gianinido for the New York Athletic 
 Club ? Why did Nansen take no alcohol with him when he left the Fram ? 
 
 CHAPTER IX 
 
 Tell how you may get the standard of your heart .beat when standing. 
 How can you increase your heart beat ? By what tests can you prove 
 that your pulse shows what the rate of your heart beat is ? What dif- 
 ference do you find in your own case between your normal pulse and 
 your pulse after a short, quick run ? What other facts have you learned 
 about your pulse ? Is it by the exercise of large or small muscles that you 
 increase your heart beat the fastest ? Why does a doctor feel the pulse 
 of his patient ? What mistake did a certain frail woman make about the 
 use of her heart ? What is the opposite mistake which a bicycle rider 
 sometimes makes? What is the heart and where does it lie? How 
 large is the heart and when does it work ? How did the heart of the 
 tennis player show that it was overtaxed ? How should the man have 
 begun his playing in the spring ? Mention some way by which muscles 
 and heart and breathing apparatus may all be trained at the same time. 
 Describe the work of the doctor as he trained the man who fainted easily. 
 What objection is there to an overstretched heart muscle? Think of 
 some advantages that come from having a heart well-trained for its work. 
 What difference is there in the size of the heart of wild and caged ani- 
 mals ? How may you train your own heart ? 
 
 CHAPTER X 
 
 To what two men do we owe the largest debt for our knowledge 
 about the heart and the circulation of the blood ? When did Galen live ? 
 
226 THE BODY AT WORK 
 
 Mention some facts about circulation that were known before Galen 
 made his discoveries. What mistake did those ancients make about the 
 contents of the arteries ? What made them think the arteries carried 
 vital spirits instead of blood ? Where did Galen practice medicine ? 
 What was his first great discovery ? What connection did he think there 
 was between the heart and the blood ? Who was William Harvey ? 
 Where was he lecturing in 1 6 1 6 ? What did he notice about the flow of 
 blood from different wounds ? What was Harvey's first great discovery ? 
 Give some facts that led him to this discovery. How many quarts of 
 blood are there in the body ? How much blood does the heart send out 
 each time it contracts ? How often does it contract each minute ? Where 
 are the pockets in the veins ? Which are deeper in the body, arteries or 
 veins ? Describe the experiment with the bandage above the elbow. 
 What does it prove ? What was Harvey's second discovery ? What can 
 you say about the two halves of the heart ? What connection does each 
 side have with pure and impure blood ? 
 
 CHAPTER XI 
 
 Describe the experiment which shows how long it takes blood to make 
 the circuit of the body. How long does this take for a man ? for a 
 child of fourteen ? Describe the circuit of the blood from the veins back 
 to the veins. How does the blood get from the arteries to the veins for 
 its return journey to the heart ? What does the microscope show in the 
 tail of a tadpole ? When you cut yourself and blood flows, what have you 
 actually done ? What does capillary mean ? What can you say about the 
 amount of blood which the blood vessels might hold ? In what way is 
 warm salt water sometimes useful in the blood vessels ? What connection 
 is there between exercise and the amount of blood which is sent to dif- 
 ferent parts of the body ? Give this law of exercise. 
 
QUESTIONS 227 
 
 CHAPTER XII 
 
 What is the object in using a rough towel after the morning bath ? 
 Describe the way to get a drop of blood for examination. Why do you 
 put the needle in the flame before using it ? In getting the blood what 
 have you done to the capillaries ? What is the color of the blood ? How 
 do you know that blood hardens soon after it leaves the body ? What 
 happens to the bit of jelly after it has been left undisturbed for about half 
 an hour? What can you say about the value of blood while a wound 
 heals ? What does a drop of blood show when it is examined through a 
 microscope ? What three things are mixed together to form blood ? 
 Tell all you can about red corpuscles. Describe white corpuscles. What 
 is the liquid part of blood called ? Describe it. What does a chemist 
 have to say about blood ? 
 
 CHAPTER XIII 
 
 What can you say about the importance of getting the blood into 
 close contact with muscle and gland ? Describe an experiment with 
 tumblers which proves that certain substances can pass through a moist 
 animal membrane. What have men discovered about the power of cer- 
 tain gases to pass through animal membrane ? How will you apply these 
 experiments to the work done by the liquids and the gases within the 
 body ? What is lymph like, and where is it found ? Which gas passes 
 from the tissues of the body into the lymph ? How does this gas reach 
 the red corpuscles ? How does oxygen from the red corpuscles get to 
 the tissues ? Which two gases change places in the red corpuscles ? Tell 
 what you can about blood in the arteries. Describe blood in the veins. 
 Describe lymph. Describe the origin of lymphatic tubes. What is the 
 difference between the system of blood vessels and the system of 
 lymphatic tubes ? What does lymph look like ? What does plasma re- 
 ceive from lymph ? What does lymph receive from plasma ? Of what 
 
228 THE BODY AT WORK 
 
 use are pocket valves in the lining of the lymph tubes? How does 
 vigorous exercise help the body through the lymph ? Why is it an 
 advantage to the tissues to be surrounded by fresh lymph? 
 
 CHAPTER XIV 
 
 When the nose or any other part of the body is red, what do we 
 understand about the capillaries just there ? What objection is there to 
 having blood move slowly through the capillaries ? Mention two advan- 
 tages that are connected with fast-moving blood. Why should the walls 
 of the blood vessels be kept healthy, vigorous, and elastic? What did 
 doctors formerly think about the connection between alcohol and 
 circulation ? After a man takes alcohol, does his heart beat faster or 
 slower ? What is the sphygmograph for ? What does the sphygmograph 
 show about the power of the heart before and after alcohol has been 
 used ? It beats faster, to be sure, but what about the force which it puts 
 into each stroke ? Does this prove that the heart receives strength or is 
 robbed of strength by the alcohol ? What is the natural condition of the 
 blood tubes ? Are they elastic or nonelastic ? What effect does alcohol 
 have on them ? Why is it harmful to have slightly paralyzed blood tubes ? 
 What effect has alcohol on the heart ? Describe what the result is when 
 both blood tubes and heart are thus weakened. What finally happens 
 to the walls of the tubes ? What effect does this have on the exchanges 
 between plasma and lymph ? Why does the body suffer when the 
 exchanges are made slowly ? Describe the condition of the heart after 
 it has been weakened by alcohol. What objection is there to fat among 
 the fibers of the heart ? Why do surgeons dread to operate on a man 
 who uses alcohol ? 
 
 CHAPTER XV 
 
 If you were ever thoroughly out of breath, describe the sensations. you 
 had. When you stopped running, which was most tired, your heart, your 
 
QUESTIONS 229 
 
 lungs, or your legs ? While you ran, what was happening to the sub- 
 stance of the living tissues of the body ? What gas was produced by the 
 tissues as they worked ? What gas did they need in order to carry on 
 their work ? Through what stream did the tissues get rid of their 
 carbon dioxid and receive their oxygen ? Why did the blood stream need 
 to flow fast ? Give five steps that are connected with breathlessness. 
 What did people formerly think was the cause of breathlessness ? What 
 do people think about it now? W T hat can be done to strengthen the 
 heart? When does carbon dioxid form fastest? When do we use the 
 most oxygen ? When does a man give off the least carbon dioxid and 
 call for the least oxygen ? Why is the heart overtaxed when we run 
 hard ? What does a trained athlete learn about keeping the balance of 
 the gases in his blood ? When is he willing to be breathless ? During 
 exercise, which muscles call for the most oxygen in the least time ? 
 Which two organs of the body need to be trained in their relation 
 to each other? 
 
 CHAPTER XVI 
 
 Mention some tests which show that the size of the lungs can be 
 increased. How many lungs have we ? Where are they ? What is an 
 air sac ? When is blood called impure ? When is blood pure ? What is 
 the condition of the blood when it enters the lungs ? when it leaves the 
 lungs ? In what way are the lungs a storehouse ? What exchange goes 
 on in the air sacs ? Where is the oxygfen taken by the red corpuscles ? 
 Is it for the benefit of the lungs or of the tissues that we breathe? 
 How long does it take blood to make the circuit of the body ? Describe 
 the way oxygen and carbon dioxid change places. in the lungs. Why are 
 large lungs an advantage to the body ? How may their size be increased ? 
 What are the best kinds of exercise for the lungs ? What danger comes 
 from inactive air sacs ? Where does tuberculosis most often begin ? 
 Why should breathing be done through the nose and not through the 
 mouth ? Why should air be well cleaned before it enters the air sacs ? 
 
230 THE BODY AT WORK 
 
 CHAPTER XVII 
 
 Give the chemist's reason for objecting to alcoholic drinks. Who was 
 Dr. Warren? How many samples of adulterated liquors did he find 
 among the six hundred which he examined ? Mention some of the poisons 
 used in adulterating the liquors. What did the manager of the St. Louis 
 Wholesale Liquor Association say about adulterations ? Give two 
 reasons why alcoholic drinks are adulterated. What must the drugs 
 do for the drink ? Which is the more dangerous, pure alcoholic drinks 
 or adulterated drinks ? Why ? Give the case of the two men who 
 drank whisky. What did Dr. Cox discover about the whisky ? Tell the 
 story of the two fishermen. Which would be safer, to get a liquor 
 dealer's recipe book and mix our own drinks, or to buy drinks as they 
 are sold? Why? What did Mr. Redding discover about port wine? 
 How can we tell whether an alcoholic drink is adulterated or not? 
 Does it often happen that those who use adulterated drinks die sud- 
 denly ? How do we know that their lives are shortened by their drink- 
 ing ? (The answer is in the eleventh chapter of Town and City.) What 
 is the great objection to patent medicines ? In which medicines is there 
 a large per cent of alcohol? What does the United States law about 
 patent medicines demand ? How can we tell whether a bottle contains 
 poisons or not ? 
 
 CHAPTER XVIII 
 
 What men were used as a sort of laboratory for food experiments ? 
 From what department of the army service did they go ? In what town 
 were the tests made ? What special treatment did the men receive ? 
 Did they eat more or less than other men? What was the result? 
 What did the tests prove about the need a man has for meat? Who 
 should eat most and who should eat least? Mention two things that 
 food does for the body. Mention the five food substances. Whence do 
 
QUESTIONS 231 
 
 plants get their nourishment ? Whence do animals get theirs ? Which 
 kind of food contains the most proteid ? What two kinds of food does 
 the word " carbohydrate " include ? Is carbohydrate most abundant in 
 the food we get from plants or in that which we get from animals? 
 W 7 hich food substance does the body use in building up tissue ? Which 
 does it use as fuel for energy ? Which for warmth ? When too much 
 carbohydrate is eaten what becomes of the surplus ? When too much 
 proteid is eaten what becomes of the surplus ? When does a person need 
 the most proteid and the most carbohydrate ? If we do not eat meat, 
 what articles should we use instead, to supply ourselves with proteid ? 
 Plan some meals where the proteid is supplied by something else than 
 meat. (You will need to study the table for this.) Why are creamed 
 potatoes more nourishing than potatoes boiled in water? Why is 
 macaroni and cheese a most nourishing dish ? Why would it never 
 do to take our nourishment in condensed tablets ? 
 
 CHAPTER XIX 
 
 Where did Dr. Cannon conduct his experiments on cats ? Why were 
 cats chosen ? Why was bismuth mixed with the cats food ? What did 
 Dr. Cannon wish to learn about the stomach? Why did he use the 
 X-rays ? Describe the waves of motion. Describe the changing shape 
 of the stomach. How soon after eating did the food begin to leave the 
 stomach ? What is the name of the muscle that guards the outlet ? 
 Describe the uneven action of the pylorus after the cat swallowed the 
 tablet of bismuth and starch paste. What did this experiment prove ? 
 Why is it a disadvantage to have food detained too long in the stomach ? 
 What discovery did Dr. Cannon make in connection with the cat that lost 
 its temper? What emotions have the power to stop all action of the 
 stomach ? What effect does a happy mind have on the work which the 
 stomach does ? 
 
232 THE BODY AT WORK 
 
 CHAPTER XX 
 
 What is food in the stomach called when it is soft enough to pass 
 through the pylorus ? How long is the small intestine ? How thin is 
 chyme when it passes through the pylorus ? What makes it grow thinner 
 yet in the food tube? What is chyme called after it enters the food 
 tube ? Describe the action of the food tube as it was studied by means 
 of the X-ray. How rapidly did the peristaltic action take place ? How 
 fast did the chyle move through the tube ? Would rapid movement of 
 the chyle be an advantage or a disadvantage to the body ? Where are the 
 villi ? What are they for ? Why is chyle squeezed up against them so 
 often ? If food is not absorbed by the villi, what becomes of it ? From 
 the time food is cooked and eaten until its journey is ended, what is 
 all the preparation for ? How many villi are there ? What is each one 
 like ? What do they do ? What is the great object of peristaltic action ? 
 What happens when the food is not thoroughly prepared for the villi ? 
 Where, then, does food meet its final test ? What happens to food if it is 
 kept too long either in the pantry or in the food tube ? Give some 
 reasons why a person may be only half nourished although he swallows 
 a good deal of food. Describe the progress of a mouthful of food from 
 the time it is put in the mouth until it reaches the villi. 
 
 CHAPTER XXI 
 
 Tell what you can about the effect of tempting a dog with meat ? 
 How many sets of salivary glands are there ? What two things make 
 saliva flow ? Have you tested yourself in both these directions ? Why 
 does a sensible man with a weak stomach eat dry toast rather than deli- 
 cate custard ? How does saliva affect starch ? What does it do to certain 
 kinds of sugar that are hard to digest ? Give two reasons why we chew 
 food thoroughly. (First, to soften it ; second, to mix it with saliva, which 
 will change it and prepare it for its next course of treatment.) Why 
 
QUESTIONS 233 
 
 should babies, and older persons also, take their milk in sips, and not 
 in a pouring stream ? What can gastric juice do to raw meat ? Which 
 needs the most chewing, raw or cooked meat? Describe the gastric 
 glands. Describe the tests with dogs which proved certain points about 
 the flow of gastric juice. What should always be done after tempting a 
 dog with food ? Under what circumstances does gastric juice flow fastest 
 and longest ? What can you say about the advantages of hunger ? Give 
 two reasons for cooking food. What does cooking do to starch cells ? 
 Why should oatmeal and other cereals be thoroughly cooked ? 
 
 CHAPTER XXII 
 
 What is the name of the largest gland of the body ? Where does it 
 lie ? How much does it weigh ? What does the liver do with the liquid 
 food which it receives from the villi ? What is glycogen for ? What does 
 the liver do with venous blood ? What is bile good for ? Mention the three 
 occupations of the liver. What does a doctor sometimes advise a man to 
 do when he has liver trouble ? Why is a piece of raw liver so bloody ? 
 Why is alcohol especially harmful to the liver ? How large does a liver 
 sometimes become through the use of alcohol ? What objection is there 
 to fat in the liver ? Where are the kidneys ? What do they look like ? 
 What do they do ? If they are out of order and cannot clear the blood 
 of its proteid waste, what becomes of this waste ? What diseases follow ? 
 What do insurance companies think of a man whose kidneys are out of 
 order ? What do scientists say about the effect of alcohol on the kidneys ? 
 Why is beer especially harmful? (Because it is -a weak drink, generally 
 taken in large quantities.) 
 
 CHAPTER XXIII 
 
 Describe a fashion-plate woman. What harm is she doing to her 
 liver ? Why will her complexion probably suffer ? What does lacing do 
 
234 THE BODY AT WORK 
 
 to the stomach ? How does lacing affect the food tube ? What is the 
 diaphragm ? Describe its location. What work does it do ? What organs 
 lie below it ? What is above it ? What tubes pass through the diaphragm ? 
 What work is done by the organs above the diaphragm ? What is done 
 by the organs below the diaphragm ? In what way is the diaphragm 
 connected with breathing? When you contract your diaphragm, is air 
 drawn in or expelled from the lungs ? When the diaphragm contracts 
 what does it do to the organs below it ? What organs are helped by the 
 exercise which this regular action of the diaphragm gives them ? How 
 does lacing interfere with the work of the diaphragm ? What effect does 
 lacing have on the lungs and on the heart ? For best health, how loose 
 should the clothes be ? Why should weights be kept from dragging 
 down on the abdominal wall? 
 
 CHAPTER XXIV 
 
 Where and what is Okushiri ? What was the occupation of the 
 inhabitants? What was their condition in 1884? How did they solace 
 themselves ? What kind of man was the governor and what did he 
 advise his people to do ? Tell what you can about the formal statement 
 which some of them drew up. What was the object of this statement ? 
 Who were asked to sign it ? When was this done ? Mention some of 
 the things to which they pledged themselves. How were the fines to be 
 spent ? How long was the contract to be in force ? How many signed 
 the contract ? At the end of the five years what was the condition of 
 the Okushiri islanders ? How were they then regarded by neighboring 
 people ? What did they then decide to do for the next five years ? If 
 you care to do so, find out the price of one glass of beer, and also the 
 price of various articles of food, and decide for yourself how much a 
 man can buy during one year with what he might have spent for three 
 glasses of beer a day during that year. 
 
QUESTIONS 235 
 
 CHAPTER XXV 
 
 What report was posted on the important buildings of Paris in 1902 ? 
 By whom was the report made ? Mention some of the statements which 
 it contained. Why are different nations protesting against alcohol ? How 
 do anti-alcohol leagues do their work ? Tell something of what is being 
 done in Germany. Who are the most prominent men in this German 
 movement ? What can you say about the royal family of Sweden ? 
 What has Japan done in the line of prohibition? In 1908, in the 
 United States, how many people were living under anti-alcohol laws 
 which they themselves had made ? What danger threatened Indian 
 Territory in 1905 ? How long had the Five Civilized Tribes been 
 protected from alcohol by the United States government ? What did 
 Indian Territory dread if it should become a state ? Who were inter- 
 ested in keeping alcohol out? Who were anxious to let alcohol into 
 the new state ? Tell what you can about the activity of each side. How 
 long did the agitation last ? After Indian Territory was joined to 
 Oklahoma what was the new state called ? Give in your own words a 
 part of the temperance law which now protects Oklahoma from alcohol. 
 
 CHAPTER XXVI 
 
 What were scientists trying to learn about the heat of the body in 
 1775? Describe the way they tested their bodies in heated rooms. 
 How hot was the air ? What happened to beefsteak, eggs, water, and 
 watch chains that were in the same room ? How did the men feel ? 
 What saved them from being cooked ? When were the sweat glands 
 most active ? How many sweat glands is a human being supposed to 
 have ? Describe the epidermis. Describe the dermis and tell what is 
 in it. Describe perspiration. How does it keep the skin cool? What 
 things are mixed with perspiration upon an unwashed skin ? From what 
 part does new skin grow to cover a wound ? When a wound is too large 
 
236 THE BODY AT WORK 
 
 to be covered by skin that grows from the edges, what is done to supply 
 a man with new skin ? When is perspiration called " insensible " ? What 
 is sensible perspiration ? When a man is heated, what happens to the 
 capillaries ? When a heated man sits in a draft what do the capillaries 
 do ? Where is the blood sent from these capillaries ? What is generally 
 the first symptom of a cold ? Describe the behavior of white corpuscles 
 at such times. When white corpuscles are inactive what about the 
 microbes? Why is a man who has a cold more liable to take other 
 diseases ? If you feel a cold coming on, what should you do to check it ? 
 In what ways may we take cold by chilling the blood ? 
 
 CHAPTER XXVII 
 
 What can you say about the heat of the body in different countries ? 
 What is the normal temperature of a human being? Which animals 
 are warm-blooded ? What is the difference between warm-blooded and 
 cold-blooded creatures ? Why does a room grow warm when several 
 people are present? Why do we wear more clothes at one time than 
 at another ? How does exercise help keep the body warm ? What con- 
 nection is there between food and the power of the body to heat itself 
 by exercise ? When much exercise is taken what stored-up fuel is drawn 
 upon ? What may a fat man do to change his appearance ? How can, 
 you explain the fact that hard exercise has little effect on the inside 
 temperature of the body ? Since the body can cool itself when it is too 
 warm, what is the danger ? Give three rules for preventing the escape 
 of heat when the body needs it. Are we warmed by keeping the cold 
 out, or by keeping the heat of the body in ? Why do we choose flannel 
 for winter and cotton for summer wear ? Give four rules that help the 
 body to adjust itself to heat and cold. What is the great work of hygiene ? 
 
GLOSSARY 
 
 KEY TO PRONUNCIATION 
 
 a as in fate, senate, fat, arm, all, ask, what, care. 
 
 e " mete, event, met, her, thre, obey. 
 
 ee " feet. 
 
 i " ice, idea, it, sir, machine. 
 
 o " old, obey, not, move, wolf, son, horse, work. 
 
 oo " food, foot. 
 
 u " use, unite, up, fur, rule, pull. 
 
 y " fly, myself, baby, myrrh. 
 
 au " author. 
 
 aw " saw. 
 
 oy " boy. 
 
 c (unmarked) as in call ; 
 
 ch (unmarked) " child 
 
 g (unmarked) " go; 
 
 ng as in ring. 
 
 g(=z) " is. 
 
 th (unmarked) as in thin 
 
 ew as in new. 
 
 oi as in boil. 
 
 ou " out. 
 
 ow " cow. 
 
 5 " mice. 
 
 
 ^h " chaise ; 
 
 h(= k) as in school. 
 
 g(=j) " cage. 
 
 
 n( = ng) " ink. 
 
 ph(=f) as in phanto 
 
 si(=sh) " tension; 
 
 si (= zh) " vision. 
 
 th 
 
 (unmarked) 
 
 vex; x(=gz) 
 
 then. ti ( = sh) " motion, 
 exact. 
 
 Obscure sounds : a, e, i, etc. Silent letters are italicized. 
 
 a dul'ter ate, to corrupt by mixing 
 with inferior materials. 
 
 al I mgn'ta ry, pertaining to food. 
 
 al I mgn'ta ry canal, the food canal. 
 
 am 'bush, a lying in wait. 
 
 a or'ta, the great artery from the 
 heart. 
 
 ar'chit8ct, one who plans build- 
 ings. 
 
 ar'ter y, one of the vessels or tubes 
 
 which carry the blood from the 
 
 heart. . 
 ath'lete, one trained to exercises 
 
 of agility and strength, 
 afro phy, wasting away from lack 
 
 of nourishment. 
 
 b8v r er age, drink of any kind. 
 
 237 
 
2 3 8 
 
 THE BODY AT WORK 
 
 j a muscle having two heads; 
 the term is applied to a muscle 
 in the arm. 
 
 ca"p'il la ry, one of the fine vessels 
 or tubes connecting the arteries 
 and veins. 
 
 car'bon di ox 'id, carbonic acid ; a 
 gas. 
 
 car'ti lage,an elastic tissue; gristle. 
 
 ehyle, the contents of the small 
 intestine. 
 
 chyme, food in the form in which 
 it passes out of the stomach. 
 
 Qir cu la'tion, moving in a circle or 
 circuit. 
 
 qir'cu la to ry, pertaining to circu- 
 lation, as of the blood. 
 
 co'ca Ine, a drug which produces 
 local insensibility. 
 
 con 'cave, curved in. 
 
 con traVtion, a shrinking; shorten- 
 ing. 
 
 cor'pus cle, a minute particle ; 
 blood corpuscles, the blood 
 disks or cells. 
 
 crude, raw, not fitted for use by 
 any artificial process. 
 
 cur'va ture, a bend ; a curve. 
 
 der'mls, the second layer or true 
 skin. 
 
 m, a muscle separating 
 the chest from the abdomen. 
 
 6p I der'mis, the outer layer of 
 
 skin, 
 e v&p'6 ra'tion, conversion of a 
 
 fluid into vapor. 
 
 gel 'a tin, a substance made by boil- 
 ing bones and other animal tis- 
 sues. It is used in glue and as 
 a jelly for food. 
 
 glob'iile, a little globe. 
 
 gly'co g6n, a substance found in 
 many animal tissues, and espe- 
 cially abundant in the liver. 
 
 gym'nast, one skilled in athletic 
 exercises. 
 
 hi'ber nate, to pass the winter in 
 a torpid state, as some ani- 
 mals do. 
 
 In gre'dl ent, one of the elements 
 of a combination, as a drink, or 
 medicine. 
 
 lat'er al, side wise. 
 
 league, persons united for some 
 particular purpose. 
 
 Hg'a rnent, the tissue that connects 
 bones. 
 
 lymph, a colorless fluid in animal 
 bodies. 
 
 lym phat'Ic, a vessel which con- 
 veys lymph. 
 
GLOSSARY 
 
 239 
 
 mgm'brane, a thin, soft tissue in 
 the form of a sheet or layer 
 covering parts of the body. 
 
 mi'cro scope, an instrument for 
 examining objects too small for 
 the naked eye. 
 
 mus'cle, a tissue in animal bodies 
 whose contraction causes mo- 
 tion. 
 
 mus'cular, having well-developed 
 muscles ; strong. 
 
 nor'mal, regular ; natural. 
 nutri'tion, that which nourishes 
 or repairs the waste in tissues. 
 
 6'pi um, the juice of the poppy ; 
 
 a drug. 
 or gan'ic, pertaining to objects that 
 
 have organs ; hence pertaining 
 
 to the animal and vegetable 
 
 worlds. 
 ox'y g6n, the element of the air 
 
 that supports life. 
 
 pSr'a lyze, to render helpless. 
 pat'ent mgcl'I qlue, a drug, the sale 
 
 of which is secured by law as 
 
 the special privilege of the pro- 
 
 prietor. 
 p8r I stal'tlc, contracting in suc- 
 
 cessive circles. 
 pig'ment, coloring matter. 
 plas/ma, the liquid part of the blood. 
 
 pie be'/ an, pertaining to the com- 
 mon people. 
 
 pro'te id, food stuffs which form 
 tissues are proteids. 
 
 pulse, the beating of the heart as 
 felt in the arteries. 
 
 pylo'rus, the opening through 
 which the contents of the 
 stomach pass into the intestine. 
 
 reg i mgn'tals, military clothing. 
 
 rAyth'mlc, sounds occurring regu- 
 larly, as accents in poetry or 
 music. 
 
 rlt'k'e'ts, a disease of children, in 
 which they are weak in the 
 joints. 
 
 ro'tate, to revolve ; to move round 
 a center. 
 
 sak'e, a Japanese fermented liquor 
 
 made from rice. 
 
 sal i cyl'ic, the name of an acid, 
 sal 'I va ry, pertaining to saliva, 
 sar co lem'ma, the covering of sep- 
 arate muscle fibers, 
 sphyg'mo graph, an instrument 
 
 used in determining the strength 
 
 of the heart beat, 
 stim'ulant, that which excites; a 
 
 medicinal agent for increasing 
 
 vital activity, 
 sym met'rlc al, well proportioned 
 
 in its parts. 
 
240 
 
 THE BODY AT WORK 
 
 syr'mge, an instrument like a pump, 
 drawing in and ejecting liquids. 
 
 tf, the young of a frog. 
 tSn'don, a bundle of fibers which 
 
 joins a muscle to a bone. 
 tgnsely, tightly; rigidly. 
 tro'phy, a memorial of victory. 
 
 vein, a vessel which receives blood 
 from the capillaries and returns 
 it to the heart. 
 
 ver'te bra, one of the joints of the 
 spine. 
 
 vil'lus (plural, villi), a minute ele- 
 vation on the lining of the small 
 intestine. 
 
INDEX 
 
 Abdomen, effect of lacing on, 183, 184. 
 
 how walls of, may be strengthened, 
 188. 
 
 injury from weight of skirts on, 189. 
 Africa, 212. 
 Air sacs, where located, 126. 
 
 relation of, to capillaries, 127. 
 
 when inactive, 129. 
 
 Alcohol, effect of, on circulation, ni- 
 114. 
 
 adulteration of, 132-135. 
 
 why adulterated, 133. 
 
 examination of, 132, 134. 
 
 fishermen killed by, 135. 
 
 materials used in adulteration of, 
 132, 136. 
 
 effect of, on health, 136. 
 
 in patent medicines, 137, 138. 
 
 effect of, on the liver, 175-177. 
 
 effect of, on kidneys, 178, 179. 
 
 prohibition of, by Okushiri is- 
 landers, 192-195. 
 
 posters against use of, 197. 
 
 German attitude in regard to, 199. 
 
 protection against, in the United 
 States, 200, 201. 
 
 law against, in Japan, 200. 
 
 fight against, by Oklahoma, 202, 203. 
 American army, refusal of candidates 
 
 for, 64. 
 
 Anderson, Dr., 141. 
 Anti-alcohol leagues, 198. 
 Aorta, 82. 
 Arkansas, 202. 
 Arteries, early notions about, 77-80. 
 
 condition of, after death, 78. 
 
 Arteries, nature of blood flow from, 
 when ruptured, 81. 
 
 constricted by bandage, 84. 
 
 union of, with veins, 90. 
 Athletic leagues, object of, 60. 
 
 how conducted, 60, 61. 
 
 reasons for self-denial in connec- 
 tion with, 61, 62. 
 
 Athletics, for New York boys, 58. 
 Auricle, 86. 
 
 Beer, effect of, on kidneys, 179. 
 
 expense of, to the consumer, 196. 
 Bile, where manufactured, 174. 
 
 work of, 174. 
 Blood, circulation of, as understood by 
 
 Galen, 78-80. 
 
 as understood by Harvey, 80-83. 
 amount of, in human body, 82, 92. 
 pure and impure, 87. 
 rate of circulation of, 88. 
 movement of, through capillaries, 
 
 91. 
 supply of, controlled by exercise, 
 
 95, 96. 
 
 to secure drop of, 97. 
 characteristics of, 97, 98. 
 composition of, 99, 100. 
 value of, to the body, 100, 101. 
 character of, in arteries, 104. 
 character of, in veins, 104. 
 effect of slow movement on purity 
 
 of, no. 
 circulation of, affected by alcohol, 
 
 113, 114. 
 reason for rapid movement of, 120. 
 
 241 
 
242 
 
 THE BODY AT WORK 
 
 Blood, color of, affected by carbon 
 dioxid, 121. 
 
 when pure and when impure, 126. 
 
 treatment of, by the liver, 173, 174. 
 Blood vessels, in connective tissue, 29. 
 
 capacity and elasticity of, 92, 94. 
 
 when refilled with salted water, 94. 
 
 surroundings of, 105. 
 
 exchanges through walls of, in. 
 
 affected by alcohol, 114. 
 Body, shape of, influenced by exercise, 
 
 training of, to endure, 22. 
 changes in temperature of, 217,218. 
 Bones, measurement of, i, 2. 
 shaped by pressure, 3-6. 
 laws of growth of, 7. 
 records made by, 9. 
 influenced by habits at school desk, 
 
 I I, 12. 
 
 outside structure of, 34, 36. 
 
 internal structure of, 36. 
 
 when treated with acid, 36. 
 
 lime of, how secured, 36. 
 
 composition of, 36. 
 
 condition of, during youth and age, 
 
 37- 
 
 when pliable, 37, 38. 
 shapes of, 39. 
 how made larger and rougher, 41, 
 
 43- 
 
 of the foot, 45-47. 
 Bowlegs, cause of, 4. 
 Breathing, why best through nose, 131. 
 Breathlessness, description of, 117, 118. 
 
 relation of muscles to, 119. 
 
 three steps in production of, 120. 
 
 old notion about cause of, 120. 
 
 relation of, to exercise, 121. 
 
 cause of, 122. 
 
 how regulated, 123. 
 
 Cannon, Dr., 149, 150, 152-155, 160. 
 Capillaries', description of, 90-92. 
 
 Capillaries, when broken into, 97. 
 
 exchange of liquids and gases 
 through the walls of, 102-105. 
 
 destruction of, by electricity, 109. 
 
 when distended, 109, no. 
 
 in the lungs, 127. 
 
 condition of, during exercise, 209. 
 Carbohydrate, its nature, 143. 
 
 value of, to the body, 143, 146. 
 
 proportion of, in human body, 147. 
 
 effect of saliva on, 166, 167. 
 
 disposal of surplus of, 178. 
 Carbon dioxid, in lymph, 104. 
 
 production of, by exercise, 119. 
 
 amount of, given off under differ- 
 ing conditions, 121. 
 
 in arterial blood, 122. 
 
 expulsion of, from lungs, 127. 
 Cartilage, 4, 15. 
 Cats, study of, during digestion, 149- 
 
 155- 
 
 Chinese shoe and foot described, 44,45. 
 Chittenden, Professor, 139, 142, 146. 
 Chyle, where found, 158. 
 
 treatment of, by villi, 163. 
 treatment of, by food tube, 160. 
 acceptance of, by the villi, 162. 
 Chyme, passage of, through pylorus, 
 
 152. 
 
 on leaving the stomach, 157. 
 Cigarettes, why given up by school- 
 boys, 62. 
 
 to investigate effects of, 63. 
 Circulation of blood, discoveries about, 
 
 by Galen, 78-80. 
 discoveries about, by Harvey, 80- 
 
 83- 
 
 time required for, 88. 
 effect of alcohol on, 111-114. 
 Clothing, value of flannel as opposed 
 
 to cotton fabrics for, 217. 
 Cold, symptoms of, 209. 
 cause of, 210. 
 why objectionable, 210. 
 
INDEX 
 
 243 
 
 Cold, treatment of, 210-211. 
 
 to prevent taking, 216. 
 Connective tissue, where found, 29. 
 
 relation of, to tough and tender 
 
 meat, 30. 
 Corpuscles, under the microscope, 98, 
 
 99- 
 
 description of, 99, 100. 
 Corpuscles (white), behavior of, during 
 
 a cold, 209, 210. 
 Courtney, C. E., 65. 
 Cox, Dr. Hiram, 134. 
 Curvature, cases of, in different schools, 
 
 12, 13. 
 
 how secured at desk, 14, 15. 
 why objectionable, 15. 
 how prevented, 16, 17. 
 
 Debove, Professor, 197. 
 Dermis, description of, 207. 
 Diaphragm, location and structure of, 
 184, 185. 
 
 work of, 185. 
 
 effect of lacing on use of, 185, 186. 
 Digestion, study of, by X-Rays, 149- 
 
 155- 
 
 result when process of, is slow, 153. 
 effect of emotions on, 154, 155. 
 relation of mental condition to, 156. 
 how hindered by waste, 161. 
 how helped by mastication, 166- 
 
 168. 
 
 how helped by appetite, 170. 
 Dogs, food experiments with, 165, 169. 
 
 Edwards, Mr., captain of Princeton 
 
 football team, 65. 
 Elephant with sprained ankle, 51. 
 Epidermis, description of, 207. 
 Exercise, why taken between recita- 
 tions, 14. 
 
 curvature prevented by, 16, 17. 
 effect of, on shape of body, 18-23. 
 taken without apparatus, 24-27. 
 
 Exercise, effect of, on muscle fiber, 30. 
 effect of, on bones, 41, 43. 
 for flat feet, 47. 
 need of, in cities, 59. 
 secured through athletic leagues,6o. 
 to study effect of, on heart, 68-70. 
 in training of the heart, 71-75. 
 relation of, to blood supply, 95, 96. 
 advantage of, to flow of lymph, 107. 
 production of carbon dioxid by 
 
 means of, 119, 120. 
 relation of, to demand of muscles 
 
 for oxygen, 120, 121. 
 relation of, to breathlessness, 121- 
 
 123. 
 lung capacity increased by, 125, 
 
 129, 130. 
 
 effect of, on abdomen, 188. 
 effect of, on capillaries, 209. 
 relation of, to bodily temperature, 
 
 214. 
 
 effect of, on fat, 215. 
 cooling off after, 216. 
 
 Fat, a food substance, 144. 
 as reserve fuel, 215. 
 how reduced by exercise, 215. 
 Faisans, Dr., 197. 
 Five Civilized Tribes, treatment of, by 
 
 the United States, 200. 
 Food, experiments in use of, 139-141. 
 value of, 142. 
 
 different substances in, 143. 
 tables showing differing values of, 
 
 144, 145. 
 
 value of, as bulk, 148. 
 softened in the stomach, 152. 
 advantage of mastication for, 153, 
 
 166. 
 
 progress of, through tube, 160. 
 treatment of, by digestive juices, 
 
 1 60. 
 
 condition of, when absorbed by 
 villi, 163. 
 
244 
 
 THE BODY AT WORK 
 
 Food, preparation of, for villi, 162, 163. 
 
 mistakes in use of, 164. 
 
 advantages in cooking, 170, 171. 
 
 facts concerning the use of, 172. 
 
 change of, into glycogen, 173. 
 
 relation of, to bodily heat, 215. 
 Food tube, size and length of, 157. 
 
 nourishment passing through walls 
 of, 157. 
 
 contraction and relaxation of, 158. 
 
 when clogged, 161. 
 Foot, ligaments of, 47. 
 
 bones of, 47. 
 
 flat, test of, 47. 
 
 flat, exercise for, 47. 
 
 health requirements for, 48. 
 
 rules for treatment of, 48-50. 
 
 Galen, 77-80. 
 
 Gastric glands, location and work of, 
 
 1 68. 
 
 structure of, 169. 
 Gastric juice, effect of, on food, 
 
 !59- 
 
 flow of, affected by worry, 164. 
 power of, 1 68. 
 increased flow of, 169. 
 laws controlling flow of, 170. 
 Gelatin, how secured, 36. 
 Germany, agitation against alcohol in, 
 
 198, 199. 
 Gianini, Mr., New York Athletic Club, 
 
 66. 
 
 Good Health, references to, 126, 130, 
 207. ^ 
 
 Harvard Medical School, 149. 
 
 Harvey, William, 77, 80, 83. 
 
 Heart, as affected by tobacco, 62, 64. 
 
 importance of training in develop- 
 ment of, 71, 73, 74. 
 
 how injured, 72. 
 
 description of, 72. 
 
 how overtaxed, 73-75. 
 
 Heart, condition of, when overtaxed, 
 
 75- 
 
 of wild and caged animals, 75. 
 how strengthened, 74, 76. 
 belief of Galen about, 80. 
 work of, 82. 
 
 number of beats of, per minute, 82. 
 amount of blood pumped by, 83. 
 relation of, to veins and arteries, 
 
 85. 93- 
 
 structure of, 85, 86. 
 affected by alcohol, 113-116. 
 forced work of, 120. 
 when overworked, 121. 
 training of, 121. 
 Heart beat, relation of, to pulse beat, 
 
 68, 69. 
 
 affected by quick run, 69. 
 Heat, experiments with, in 1775, 204, 
 
 205. 
 
 importance of, to the body, 213. 
 radiation of, from the body, 214. 
 relation of exercise to, 214. 
 regulation of, by perspiration, 216. 
 use of newspaper in preventing 
 
 escape of, 217. 
 Hotel de Ville, 197. 
 Hygiene, definition of, 218. 
 
 Indian Territory, alcoholic legislation 
 
 for, 201-203. 
 
 Indians, flat heads secured by, 4. 
 Intestine, small, condition of, during 
 
 digestion, 160. 
 passage of food through lining of, 
 
 162. 
 effect of lacing on, 183. 
 
 Japan, law of, against alcohol, 200. 
 Joints, assistance from, 51-57. 
 
 where located, 54. 
 
 different kinds of, 54-56. 
 
 ball-and-socket, 55. 
 
 hinge, 56. 
 
INDEX 
 
 245 
 
 Kidneys, work of, 146, 178. 
 
 location and structure of, 177. 
 how overtaxed, 178. 
 effect of alcohol on, 179. 
 
 Lacing, harm done by, 182-184, 186, 
 188. 
 
 how to avoid, 189. 
 Ligaments, between vertebrae, 41. 
 
 of foot, 44. 
 
 when strained, 51. 
 
 of knee and hip, 55. 
 
 description of, 55, 56. 
 
 work of, 56. 
 Liver, a chemical laboratory, 173. 
 
 occupations of, 173, 174. 
 
 condition of, when raw, 174, 175. 
 
 effect of alcohol on, 175-177. 
 
 effect of lacing on, 182. 
 
 work of, helped by diaphragm, 186. 
 London, residence of William Harvey, 
 
 80. 
 Lungs, expansion of, 124. 
 
 how to permanently increase size 
 of, 125, 129, 130. 
 
 description of, 125, 126. 
 
 work of, 126, 127. 
 
 advantage of size and health of, 
 128, 130. 
 
 effect of lacing on, 186. 
 Lymph, where found, 103, 106. 
 
 nature and value of, 104. 
 
 relation of, to carbon dioxid, 104. 
 
 importance of, 104. 
 
 constituents of, 105. 
 
 office of, 105. 
 
 appearance of, 106. 
 
 exchanges of, with plasma, 106. 
 
 flow of, aided by exercise, 107. 
 
 what it receives from plasma, 107. 
 
 union of, with circulatory system, 
 1 08. 
 
 when fresh, 108. 
 Lymphatic tubes, origin of, 105, 107. 
 
 Lymphatic tubes, structure of, 107 
 size of, 1 08. 
 
 McBride, Mr., 65. 
 
 Meat, substitutes for, 147, 148. 
 
 Merrimac River, 170. 
 
 Microbes, relation of, to bodily waste, 
 
 162. 
 
 Milk, why swallowed in sips, 167, 168. 
 Muscles, of back, 18, 19. 
 
 influence of hard work on, 18, 19. 
 
 law of activity of, 20. 
 
 of arm elongated, 20. 
 
 of oarsman's back, 20. 
 
 in hand of piano player, 21. 
 
 how to change undesired shape of, 
 
 22. 
 
 of chest, how strengthened, 22, 23. 
 exhibitions of, by student, 24, 26. 
 the biceps, 25, 33. 
 development of, without apparatus, 
 
 26, 27. 
 examination of, with magnifying 
 
 glass, 28. 
 
 different shapes of, 28. 
 structure of, 28, 29. 
 hard when contracted, 32. 
 voluntary, 32. 
 involuntary, 32. 
 weight of, in human body, 33. 
 relation of, to tendon and bone, 
 
 52, 53- 
 
 biceps, work of, 53. 
 as affected by exercises, 119, 120. 
 call of, for oxygen, 123. 
 work of, to reduce fat, 215. 
 
 Nansen, Mr., views of, about alcohol, 66. 
 
 New Mexico, 201. 
 
 Nippon, island of, 191. 
 
 Nose, explanation of color of, no. 
 
 Oarsmen, straight and bent backs of, 
 how explained, 20. 
 
246 
 
 THE BODY AT WORK 
 
 Oklahoma, union of, with Indian Ter- 
 ritory, 201-203. 
 Okushiri, island of, 191. 
 Okushiri islanders, history of prohi- 
 bition experiment among, 191- 
 196. 
 
 Oporto, wine exported from, 135. 
 Oxygen, in the blood, 104. 
 
 need of, during exercise, 120. 
 in the lungs, 127, 128. 
 
 Paris, anti-alcohol posters in, 197. 
 Patent medicine, harmful ingredients 
 
 of, 137- 
 
 effect of, on patient, 137. 
 
 proportion of alcohol in, 137. 
 
 action of the United States govern- 
 ment in regard to, 137, 138. 
 Pawlow, Professor, 165, 169. 
 Peristaltic action, object of, 163. 
 Perspiration, manufacture of, 206. 
 
 composition of, 207. 
 
 insensible, 208. 
 
 sensible, 209. 
 
 relation of, to taking cold, 209. 
 Plants, source of nourishment of, 
 
 143- 
 Plasma, description of, 99. 
 
 what it receives from lymph, 106. 
 Posture, importance of, 7. 
 
 correct standing, 9, 10. 
 
 at school desk, IT. 
 
 Proteid, use of, in the body, 143, 146, 
 147. 
 
 disposal of surplus of, 178. 
 Pulse beat, testing of, 67. 
 
 to increase rapidity of, 68-70. 
 
 why followed by the doctor, 70. 
 
 what shown by, 81, 82. 
 Pylorus, location and work of, 152. 
 
 how affected by soft and hard food, 
 
 152, 153- 
 Redding, Cyrus, 135. 
 
 Ribs, shape of, changed by lacing, 182. 
 
 normal shape of, 183. 
 Rome, residence of Galen, 78. 
 Royal Society of London, Philosophical 
 
 Transactions of, 206. 
 Rugby, curvature among pupils of, 13. 
 
 St. Louis Wholesale Liquor Association, 
 
 133- 
 
 Sake, use of, 191. 
 Saliva, how increase flow of, 165. 
 
 value of, 1 66, 167. 
 Salivary glands, 165. 
 Schmidt, Dr. F. A., 12. 
 School desk, danger from, n. 
 Shoes, affecting shape of foot, 48. 
 
 size of, required, 48, 49. 
 Skeleton, dependence of, on muscle 
 
 and ligament, 34. 
 Skin, protected by, 204-211. 
 
 uninjured by heat, 204, 205. 
 
 structure of, 207. 
 
 work of, how interfered with, 207. 
 
 condition of, in health, 208. 
 
 power of, to heal itself, 208. 
 Soldiers, connection of, with eating ex- 
 periments, 139. 
 
 treatment of, 140. 
 
 condition of, at close of experi- 
 ments, 141. 
 
 Sphygmograph, value of, in, 112. 
 Spinal column, importance of, 39, 40. 
 Stagg, A. A., 65. 
 Starch, in beans and in potato, 171. 
 
 effect of cooking on, 171. 
 
 effect of saliva on, 171. 
 Stockholm, temperance gathering in, 199. 
 Stomach, study of, through the X-ray, 
 149. 
 
 appearance of, 150, 151. 
 
 action of, during digestion, 151. 
 
 contents of, after fifteen minutes, 
 152. 
 
INDEX 
 
 247 
 
 Stomach, effect of lacing on, 183. 
 
 effect of rhythmic action of dia- 
 phragm on, 1 86. 
 Sweat glands, work of, 206. 
 number of, 206. 
 value of, 216. 
 
 Sweden, attitude of royal family towards 
 alcohol, 199. 
 
 Temperature of body, slight variation 
 
 of, 212, 213. 
 
 Tendons, when strained, 51, 53. 
 relation of, to muscle, 52. 
 work of, 56. 
 
 Texas, reference to, 202. 
 Tobacco, use of, forbidden to athletes, 
 
 62, 65, 66. 
 
 effect of, on heart, 64. 
 Town and City, reference to, 137, 170, 
 
 177, 200. 
 
 Treves, Sir Frederick, 116, 
 Tuberculosis, frequent starting point of, 
 129. 
 
 United States, prohibition in, 200. 
 
 action of, in regard to alcohol and 
 the Indians, 200-203. 
 
 Veins, early notions about, 77-80. 
 
 condition of, after death, 78. 
 
 nature of blood flow from, when 
 ruptured, 81. 
 
 valves of, 83. 
 
 to hinder progress of blood through, 
 84, 85. 
 
 union of, with arteries, 90. 
 Ventricle, 86. 
 
 Vertebrae, wedge shape, how secured, 
 14, 42. 
 
 number and location of, 39. 
 
 shape of, 40. 
 
 effect of posture on, 40. 
 
 movements of, 41. 
 Villi, location of, 160. 
 
 work of, 161. 
 
 numbers of, 162. 
 
 description of, 162. 
 
 absorption of food by, 163. 
 
 food sent by, to liver, 173. 
 
 Warren, Dr., 132. 
 
 Waste, regular elimination of, 162. 
 
 X-ray, action of food tube shown by, 
 159- 
 

 
Y.C 
 
 
 
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