FIRST LESSONS 
IN 
Physiology and Hygiene. 
3pr tit* 4 
BY 
CHARLES K. MILLS, A.M., M.D., 
FELLOW OF THE COLLEGE OF PHYSICIANS OF PHILADELPHIA; LECTURER ON 
MENTAL DISEASES AND ELECTRO-THERAPEUTICS IN THE UNIVERSITY 
OF PENNSYLVANIA. ETC., ETC. 
Eldredge & Brother, 
Philadelphia •. 
No. 17 North Seventh Street. 
1883. Entered, according to Act of Congress, in the year 1882, by 
ELDREDGE & BROTHER, 
In the Office of the Librarian of Congress, at Washington. 
~j v 
J. FAGAN A SON, 
ELECTROTYPERS, PHILAD’A. The object of this book is to present concisely, 
clearly, and in logical order the most important 
elementary facts in Physiology and Hygiene. Suf- 
ficient anatomy has been given to render the 
physiology intelligible. 
As far as possible, technical language has been 
avoided. The author has aimed to make each 
paragraph complete in itself, embracing a definite 
subject. 
The “Syllabus” and “Questions for Review,” 
it is believed, will be found useful not only in 
the regular course of instruction, but also for ex- 
amination purposes. 
C. K. M. 
Philadelphia, January, 1883. CHAPTER I. 
PAGE 
Introduction . . . .11 
Physiology, 11. Anatomy, 12. Hygiene, 12. Tissues and 
Organs, 12. Divisions of the Body, 13. Cavities of the 
Body, 13. Coverings of the Body, 15. The Lining Skin, 
or Mucous Membrane, 16. Glands, 16. Connective Tissue 
and Fat, 16. 
CHAPTER II. 
The Bones . . . .20 
The Skeleton, 20. Humber of Bones in the Skeleton, 20. 
Structure of Bone, 20. Composition of Bone, 22. The 
Backbone, 22. General Facts about the Bones, 23. Move- 
ments of the Spine, 26. Movements of the Head, 26. 
Uses of the Bones, 26. One-sided Development, 27. Dis- 
eases of the Bones, 27. Softness of the Bones in Early 
Life, 28. Brittleness of the Bones in Old Age, 28. Broken 
Bones, 28. 
CHAPTER III. 
The Joints . . . .33 
A Joint, 33. The Joint-Juice, or Synovial Fluid, 33. Immov- 
able Joints, 33. Movable Joints, 34. Ligaments of the 
Joints, 34. Pressure of the Air upon the Joints, 35. Un- 
usual Motion in Joints, 36. Uses of the Joints, 36. Inju- 
ries of the Joints, 37. CONTENTS. 
CHAPTER IV. 
PAGE 
Muscles and Movements . . .40 
Motion, 40. The Machinery of the Body, 40. Movements 
of the Limbs, 41. Muscle, and the Muscles of the Body, 
41. The Names of the Muscles, 43. The Different Parts 
of a Muscle, 43. The Tendon of Achilles, 43. The Struc- 
ture of Muscle, 44. Contraction of Muscles, 44. The 
Biceps Muscle, 44. Levers, 45. Levers of the Third 
Order in the Limbs, 46. Action of the Muscles in gen- 
eral, 46. 
CHAPTER V. 
Muscular Exercise . . .50 
Exercise, 50. Muscular Exercise and Muscular Contractil- 
ity, 50. Effect of Exercise on Muscle, 51. Effect of Ex- 
ercise on the Bones, 51. Effect of Exercise on Various 
Tissues and Organs, 51. Results of Systematic Exercise, 
52. Deformities Prevented or Corrected by Exercise, 53. 
Fitness, Variety, and Moderation in Exercise, 53. Time 
for Exercise, 54. A Sound Mind in a Sound Body, 54. 
CHAPTER VI. 
Modes of Exercise . . .58 
Physical Educational Exercise, 58. Systematic Exercises 
without Apparatus, 58. Movements to Promote general 
Suppleness, 59. Gymnastic Apparatus, 61. How to Sit 
and Stand, 62. Out-door Exercises, 62. Walking, 62. 
Running, 63. Swimming and Bathing, 63. Rowing, 63. 
Riding, 64. Development of both Sides of the Body by 
Exercise, 64. Open-air Games or Recreative Exercises, 65. 
CHAPTER VII. 
The Nervous System . . .69 
Regulation of the Machinery of the Body, 69. The Parts 
of the Nervous System, 70. Gray and White Matter of 
the Nervous System, 70. Divisions of the Brain, 70. 
Membranes of the Brain, 71. Functions of the Brain, 72. 
The Spinal Cord, 73. The Nerves, 73. The Cranial Nerves, VI 
CONTENTS. 
PAGE 
or Nerves of the Brain, 75. The Spinal Nerves, 76. The 
In-coming and Out-going Nerves, 76. Sensory and Motor 
Nerves, 77. Reflex Action of the Spinal Cord and Brain, 
77. The Sympathetic System of Nerves, 78. Physiology 
of the Sympathetic System of Nerves, 78. 
CHAPTER VIII. 
Sensation and the Special Senses . . 85 
Sensation, 85. The Five Special Senses, 86. Feeling, or 
Touch, 86. The Media, or Clear Parts of the Eye, 86. 
The Coats or Coverings of the Eye, 88. The Nerve of 
Sight, 88. The Bending of Light in the Eye, 89. Pic- 
tures on the Retina, 89. The Process of Seeing, 90. The 
Organ of Hearing, 91. The Nerve of Hearing, 92. The 
Process of Hearing, 92. Taste, 98. Smell, 93. 
CHAPTER IX. 
Care of the Nervous System and Sense Organs 98 
Importance of Caring for the Nervous System, 98. Exer- 
cise of the Brain, 98. Causes of Disease of the Brain and 
Nervous System, 99. Paralysis, 99. Sleep, 100. Defects 
of Sight, 101. How to Preserve Good Sight, 101. Color- 
Blindness, 102. Care of the Ears, 102. Cultivation of 
the Senses, 103. 
CHAPTER X. 
The Blood .... 108 
What Blood Is, 108. Quantity of Blood in the Living Body, 
108. Composition of the Blood, 109. The Red Corpus- 
cles, 109. The White Corpuscles, 110. Clotting, or Co- 
agulation, 110. Clotting of Blood in the Living Body, 
111. Composition of Serum, 111. Composition of Fibrin, 
112. Water of the Blood, 112. Mineral Substances in the 
Blood, 113. Uses of the Blood, 113. 
CHAPTER XI. 
The Circulation of the Blood . .117 
Machinery for Distributing the Blood, 117. The Heart, 117. 
Valves of the Heart, 118. Arteries, 119. The Veins, 121. CONTENTS. 
PAGE 
The Capillaries, 121. Contractions of the Heart, 121. 
Description of the Course of the Circulation, 123. The 
Circulation through the Liver, 124. The Spleen, 124. 
How the Tissues are Supplied by the Blood, 124. 
CHAPTER XII. 
Food .... 128 
Why we Eat, 128. Food, 128. Digestion, 129. The Differ- 
ent Classes of Food-stuffs, 129. Remarks on the Different 
Kinds of Food, 130. Quantity of Food Required, 131. 
Cooking, 131. When and How to Eat, 132. Drinks, 132. 
Pure Water, 132. 
CHAPTER XIII. 
Digestion . . . .131 
The Organs of Digestion, 137. What Takes Place in the 
Mouth, 137. Digestion in the Stomach, 138. Digestion in * 
the Small Intestine, 139. Chyle, 140. Absorption, 140. 
Lacteals, 141. The Thoracic Duct, 141. Lymphatics, 142. 
Absorption directly into the Blood, 142. The Large In- 
testine, 143. 
CHAPTER XIV. 
Breathing .... 147 
The Air we Breathe, 147. The Blood needs Oxygen, 147. 
The Chief Organs for Breathing, 148. The Part played 
by the Hose in Breathing, 149. The Windpipe, 149. The 
Voice-Box, 149. The Vocal Chords, 150. The Lid of the 
Larynx, 151. Bronchial Tubes and Air-Cells, 151. In- 
spiration and Expiration, 152. The Lungs and the Chest, 
152. The Diaphragm, 152. Stationary Air and Tidal 
Air, 153. How the Oxygen of the Air gets into the 
Blood, 153. Oxidation, 154. 
CHAPTER XV. 
The Air and Health . . .160 
Pure Air and its Relation to Health, 160. How the Air is 
kept Pure in Nature, 160. How the Air may be Rendered 
Unwholesome, 161. Amount of Fresh Air Required for CONTENTS. 
PAGE 
Health, 162. Air Spoiled by One Man’s Breath, 162. 
Excess of Carbonic Acid in the Air, 162. Deadly Effects 
of Carbonic Acid, 163. Terrible Results of Crowding, 164. 
Diseases of the Lungs and Air-passages, 164. Clothing 
with Reference to the Lungs and Breathing, 165. 
CHAPTER XVI. 
Ventilation . . . .168 
Ventilation, 168. Objects to be Aimed at in Ventilation, 
168. Natural Ventilation, 169. The Walls of Buildings 
Permeable to Air, 169. Artificial Ventilation, 170. Re- 
lation of Inlets to Outlets in Ventilating, 171. Tempera- 
ture of the Air in Living Rooms, 171. Moisture of the 
Air in Living Rooms, 172. The Ventilation of School- 
rooms and Public Buildings, 172. The Ventilation of 
Bedrooms, 173. 
CHAPTER XVII. 
Excretion, or Getting Rid of Waste Matters . 176 
Wear and Waste, 176. Wasting and Destruction are not the 
Same, 176. The Principal Waste-products of the Body, 
177. Waste Water, 177. Carbonic Acid, 178. IJrea, 178. 
Excretion, 178. The Skin as an Organ of Excretion, 179. 
The Lungs as Organs of Excretion, 179. The Kidneys as 
Organs of Excretion, 180. Similarity of the Organs of 
Excretion, 180. 
CHAPTER XVIII. 
Hints on Hygiene, Accidents, and Poisons . 184 
Rules of Simple Hygiene, 184. Asphyxia, 186. Apparent 
Drowning, 187. Asphyxia from Noxious Gases, 188. 
Heat-stroke or Heat-exhaustion, 189. Fainting, 189. 
Convulsions, 190. Burns or Scalds, 191. Sprains, 191. 
Foreign Bodies in the Eye, 191. Insects in the Ear, 192. 
Foreign Bodies in the Throat, 193. Foreign Bodies in the 
Nose, 193. Bleeding from the Nose, 193. Bleeding from 
Wounds, 194. Poisons in general, 195. Different Classes 
of Poisons, 196. LIST OF ILLUSTRATIONS. 
PIG. PAGE 
1. Cavities of the Body 13 
2. Organs of the Chest and Abdomen 14 
3. The Human Skeleton 21 
4. A Section of a Bone 22 
5. The Spinal Column 23 
6. A Vertebra 23 
7. The Skull. 24 
8. Bones of the Arm 25 
9. Bones of the Fore-Arm 25 
10. Bones of the Wrist and Hand 25 
11. The Bones of the Foot 25 
12. The Elbow-Joint 34 
13. Section of the Hip-Joint 35 
14. Principal Muscles of the Front of the Body 42 
15. Muscle Slightly Magnified 44 
16. Lever of the First Order 45 
17. Lever of the Second Order 45 
18. Lever of the Third Order 45 
19. Lever of the Third Order in the Limbs 46 
20. Calisthenic Exercise 59 
21. Dumb-Bell 61 
22. Indian Club 61 
23. View of the Left Half of the Brain 71 
24. A Back View of the Brain, and of the Spinal Cord and its 
Branches 74 
25. The Base of the Brain 75 
26. A Section of the Spinal Cord 76 
27. Section of the Eyeball 87 
28. View of the Ear 91 
29. Red and White Corpuscles of the Blood Magnified 109 
30. The Heart and Large Blood-Vessels 118 
31. Chest, Showing the Heart, Lungs, and Large Blood-Vessels. ... 119 
32. The Aorta and its Branches 120 
33. Arteries of the Fore-Arm 121 
34. The Arteries of the Head and Face 122 
35. A Vein Opened so as to Show the Valves in Parts 123 
36. The Stomach and Intestines 138 
37. The Thoracic Duct and Lymphatics 141 
38. The Larynx, Trachea, Bronchi, and Lungs 148 
39. Air-Cells Magnified 151 
40. Vertical Section of the Skin (Highly Magnified) 179 “ The pi'oper study of mankind is man.” 
Pope. FIRST LESSONS IN PHYSIOLOGY. 
CHAPTER I 
1. Physiology.—The term Physiology is derived 
from Greek words which mean a story about nature. 
At first physiology included all kinds of natural study; 
but, as the word is now employed, it is the science 
which treats of the uses and actions of living objects. 
Human physiology is a study of what is done by and 
in the living human body. It is a study about our- 
selves, about the uses and actions of all parts of our 
bodies—head and trunk, hands and feet, brain and 
nerves, stomach, heart, and lungs. It teaches us about 
the movements of the body; about feeling, seeing, 
hearing, smelling, tasting, and thinking; about eat- 
ing, breathing, keeping warm, growing, wasting, and 
dying. Animals and plants represent living nature. 
Minerals represent lifeless nature. Animals and 
plants are born, live, grow, and pass away according 
to certain laws, which differ from those regulating 
INTRODUCTION. 12 
FIRST LESSONS IN PHYSIOLOGY. 
the existence of minerals. They have parts with 
particular functions. A function is the special work 
which any part has to perform. Physiology is a 
study of these functions. Human physiology is a 
study of the functions of the human body. 
2. Anatomy.—In order to understand physiology, 
we must have some knowledge of another science, 
called Anatomy, which may be defined as the study of 
the shapes of living things and of the parts of which 
they are made. The term Anatomy is made up from 
Greek words which mean a cutting through; and its 
real meaning is dissection, or the act of cutting an 
animal in pieces. Most of what is known about 
anatomy has been learned by dissection. 
3. Hygiene.—When something has been learned 
of the formation of the body, and of its uses and 
actions, it is natural next to inquire how to care for 
it and keep it in health. We learn this by study- 
ing Hygiene, which is the science of health. The 
ancient in a goddess, or guardian 
angel, whom they called Hygeia, whose duty it was 
to watch over the health of the people. The term 
Hygiene is formed from the name of this goddess. 
4. Tissues and Organs.—The word tissue means 
“ that which is woven.” The tissues of the body are 
its solid substances. These sometimes come together 
to form organs. An organ is a part of the body which 
has a special work or function. The body is made up 
of many tissues and organs. These tissues and organs 
are composed of minute bodies called cells. These IN TROD UCTION. 
13 
cells are too small to be seen with the naked eye, 
but they have been well studied with the microscope. 
It takes many thousands of them to occupy the space 
of a square inch. They may be roughly compared 
to minute bladders. Each cell has the power of 
taking from the blood what it 
needs to build up its own kind of 
tissue. 
5. Divisions of the Body.—The 
body, for the sake of convenient 
study, may be divided into the 
head, trunk, neck, and limbs. The 
head includes all above the neck. 
The trunk is the solid, heavy por- 
tion between the neck and the legs. 
The neck is the narrow cylinder 
between the head and the trunk. 
Although a small, it is a most im- 
portant region, for through it pass 
great nerves and vessels, and also 
tubes for the passage of air and 
food. The limbs are the two arms 
and the two legs, the upper and 
the lower extremities. Each upper 
extremity is divided into the arm, 
forearm, and hand; each lower 
extremity into the thigh, leg, and 
foot. 
6. Cavities of the Body.—In 
the head and trunk are cavities containing important 
organs. The bones of the upper back part of the 
head form the cavity of the skull, or cranium, in 
Fig. l. 
Cavities of the Body. 14 
FIRST LESSONS IN PHYSIOLOGY. 
which is lodged the brain. This cavity opens by a 
hole in its lower part into a long, narrow spinal canal, 
which runs down through the back-bone, or spinal 
column, and contains the spinal cord. In the lower 
front portion of the head is the cavity of the face, 
into which the nose and mouth open. The front of 
the trunk is divided by a great partition, called the 
diaphragm, into two large cavities; the upper of 
these is the chest, the lower is the abdomen. The 
chief organs in the chest are the heart and lungs. In 
Fig. 2—Organs of the Chest and Abdomen. 
the abdomen are the stomach, intestines, liver, and 
other organs. The organs contained in the larger 
cavities of the body are called viscera. These larger INTRODUCTION. 
15 
cavities are represented in Figure 1. Some of the 
organs of the chest and abdomen are represented in 
Figure 2. 
7. Coverings of the Body.—The chief covering of 
the body is the skin. It is composed of two layers. 
The outer layer is very thin, and is called the epi- 
dermis, which means “upon the skin.” It is so thin 
and fine that it is easily rubbed off'. It washes off 
when we take a thorough bath. It is constantly 
being shed in powder or scales; but new epidermis 
forms as fast as the old disappears. In some places, 
as on the soles of the feet, the epidermis becomes very 
thick. It contains neither nerves nor blood-vessels; 
hence, cutting it does not cause pain nor draw blood. 
The lower layer of the skin is named the dermis, or 
true skin. It is well supplied with nerves and blood- 
vessels, so that cutting it causes pain and bleeding. 
The nails and hair are sometimes termed the append- 
ages of the skin, that is, they are something added, 
but not absolutely necessary to the skin. The nails 
are epidermis which has become thick and horny. 
They are slowly but constantly growing. It has been 
calculated that a person dying in his eightieth year 
has changed his nails two hundred times at least. 
Nails grow by the addition of new matter to their 
under surface and roots. They protect the ends of the 
fingers and toes, and make the fingers more useful for 
seizing small objects. Even the hair, like the nails, 
is formed from the epidermis. The true skin sinks 
in, forming a depression, or hair sac, from which the 
hair grows. 16 
FIRST LESSONS IN PHYSIOLOGY. 
8. The Lining Skin, or Mucous Membrane.— 
When it gets near the mouth, the skin changes color, 
and we have the red lips. Looking into the mouth 
and down the throat, a red, moist surface is seen; 
we have the “red lane” as it is sometimes pleasantly 
called. This red, moist lining of the mouth, throat, 
and canals and cavities beyond, is mucous membrane. 
Any thin skin or film is a membrane, and this mucous 
membrane is in reality a continuation of the outside 
skin, so that 
“ There’s a skin without, and a skin within, 
A covering skin, and a lining skin; 
But the skin within is the skin without, 
Doubled inwards, and carried completely throughout.” 
The mucous membrane, or “lining skin,” is moister 
and redder than the “ covering skin,” because its outer 
layer is much thinner than the epidermis, so that red 
blood-vessels shine through it. Moisture easily escapes 
from these vessels, and from glands which are found 
everywhere in the membrane. 
9. Glands.—A gland is an organ which separates 
materials from the blood. The materials which are 
thus separated from the blood are called secretions. 
Glands of various sizes are found everywhere in the 
body. Sometimes glands are very simple in struc- 
ture, consisting only of thin membranes and minute 
blood-vessels. Sometimes they are large and com- 
plicated organs. 
10. Connective Tissue and Fat.—Widely diffused 
throughout the body is a substance called connective 
tissue, because it binds and connects together the SYLLABUS. 
17 
various organs. It is composed chiefly of whitish 
bands or cords. So completely does this tissue reach 
to all parts of the body, that if everything else could 
be dissected away, a model of the body, composed of 
it, would be left. In many places it takes the form 
of a loose web or network. Most of the fat of the 
body is lodged in the little spaces formed by this 
network. The organs are kept neatly in place, and 
the hollow and uneven places of the body are smoothed 
out by these two substances. 
Syllabus. 
The term Physiology is derived from Greek words which mean a 
story about nature. 
Physiology is the science which treats of the uses and actions of 
living objects. Human physiology treats of what is done by and 
in a living human body. 
Animals and plants have parts with particular duties or functions. 
Physiology is a study of these functions. 
Anatomy is the study of the shapes of living things and of the 
parts of which they are made. 
The term Anatomy is. derived from Greek words which mean a cut- 
ting through. 
Hygiene is the science of health. The word is derived from the 
name of the goddess Hygeia, who, according to the Greeks, watched 
over the health of the people. 
A tissue means that which is woven. The tissues are the solid sub- 
stances of the body. 
An organ is a part of the body which has a special work or func- 
tion. 
The tissues and organs are composed of minute cells. 
Each cell has the power of taking from the blood what it needs for 
its own tissue. 
The body is divided into the head, trunk, neck, and limbs, 18 
FIRST LESSONS IN PHYSIOLOGY. 
In the head and trunk are important cavities. 
The cavity of the skull, or cranium, is formed by the bones of the 
upper back part of the head. In it is lodged the brain. 
The spinal canal or cavity runs down through the backbone, or 
spinal column. It contains the spinal cord. 
The cavity of the face is in the lower front portion of the head. 
The diaphragm divides the trunk into.an upper cavity called the 
chest, and into a lower one known as the abdomen. 
The chief organs in the chest are the heart and lungs. 
The chief organs in the abdomen are the stomach, intestines, and 
liver. 
The organs contained in the large cavities of the body are called 
viscera. 
The chief covering of the body is the skin. It is composed of an 
outer thin layer called epidermis, which is constantly cast off and 
renewed, and of an inner thicker layer, the dermis, or true skin. 
The epidermis contains neither nerves nor blood-vessels; the 
dermis or true skin is supplied with both. 
The nails are epidermis which has become thick and horny. The 
hair is modified epidermis. 
The red, moist lining of the mouth, throat, and parts beyond is 
mucous membrane. It is in reality a continuation or doubling in- 
wards of the outside skin. 
The outer layer of the mucous membrane is much thinner than the 
epidermis of the skin, so that blood-vessels shine through it, and 
moisture readily escapes from these vessels and from glands in the 
membrane. 
A gland is an organ which separates materials called secretions, 
from the blood. 
Connective tissue is diffused throughout the body, binding to- 
gether its organs. Most of the fat of the body is lodged in the little 
spaces formed by a network of connective tissue. 
Questions for Review. 
What is the derivation of the term physiology ? 
What is physiology ? 
What is human physiology ? 
Mention some of the things studied in physiology. QUESTIONS FOR REVIEW. 
19 
What represent living and what lifeless nature ? 
How do animals and plants differ from minerals ? 
What is a function ? 
What does physiology study ? 
Define anatomy. 
From what is the term anatomy derived? 
What is the real meaning of the word anatomy ? 
Define hygiene. Give its derivation. 
What does the word tissue mean ? 
What are the tissues of the body ? 
What is an organ ? 
What are cells ? How large are they ? 
What power has each cell ? 
How can the body be conveniently divided ? 
Describe each of the divisions of the body. 
How is each upper extremity divided ? 
How is each lower extremity divided ? 
How is the cavity of the skull, or cranium, formed ? 
What is lodged in the skull ? 
What is the spinal canal ? What does it contain ? 
What is the cavity of the face ? 
How is the front of the trunk divided ? 
What are the chief organs in the chest ? 
What are the chief organs in the abdomen? 
What are the viscera ? 
Of how many layers is the skin composed ? 
What is the epidermis? 
Mention some facts about the epidermis. 
What is the dermis ? What does it contain ? 
What are the appendages of the skin ? 
What are the nails ? How do nails grow ? 
What are some of the uses of the nails ? 
What is the hair ? How does it grow ? 
What is the lining of the mouth, throat, and parts beyond called ? 
What is a membrane ? 
Of what is the mucous membrane a continuation ? 
Why is it moister and redder than the skin ? 
What is a gland? What are secretions? 
What is connective tissue? Of what is it chiefly composed? 
Where is most of the fat of the body lodged ? CHAPTER II. 
THE BONES. 
11. The Skeleton.—Every animal is formed after 
a certain pattern; it has a shape of its own, which de- 
pends mainly upon its frame-work of bone, or skeleton. 
The word skeleton means a dried-up body. As usu- 
ally seen, it consists of bones which have been cleaned, 
dried, and put together with wires. In Fig. 3 a front 
view of the human skeleton is given. It is not an 
attractive picture, but in the living body its ugliness 
is hidden beneath coverings of skin, fat, and muscle. 
12. Number of Bones in the Skeleton.—The skel- 
eton contains about two hundred and eight bones, of 
which thirty are in the head, fifty-four in the trunk, 
and one hundred and twenty-four in the limbs. The 
number varies a little at different ages. Some of the 
bones which are separate in the infant or little child, 
grow together as age advances, and thus the bones be- 
come fewer in number. 
13. Structure of Bone.—Bone is firm and dense 
outside, but it has canals and cavities within, which 
give it lightness as well as strength. The outer por- THE BOHES. 
21 
Fig. 3— The Human Skeleton. 22 
FIRST LESSONS IN PHYSIOLOGY. 
tion is sometimes called the compact substance, and the 
interior the spongy substance. They are both well 
Fig. 4—A Section of a Bone. 
represented in Fig. 4, which is a view of a section of 
bone. 
14. Composition of Bone.—Bones are composed 
of both animal and mineral matter. If about an 
ounce of muriatic acid is mixed with a pint of water, 
and a bone is placed in the mixture, in a day or two 
the mineral substance will be dissolved, leaving only 
the animal matter. The bone will still retain its form, 
but it will be so soft that it may be bent into different 
shapes, and, if a long bone, may even be tied into a knot. 
By putting the bone into an oven and carefully apply- 
ing heat, the animal matter can be burned out. The 
shape is still retained, but the bone is now hard and 
brittle. 
15. The Backbone.—The backbone, or spinal col- 
umn (Fig. 5), supports and holds together the rest of 
the body. It is a strong bony column, reaching down- 
wards from the skull, which is balanced on its summit. THE BONES. 
23 
It has four curves, two forwards and two backwards 
It is not, as the name backbone 
would indicate, a single bone, but 
is composed 
of many bones 
or vertebrae. 
The word ver- 
tebra comes 
from the Lat- 
in, vertere, to 
“turn.” One 
of these ver- 
tebrae is represented in Fig. 6. It 
has a heavy part in front, and at 
several points are projections or 
spines. By passing the hand up 
and down the back, some of these 
spines, which project backwards, can 
be felt through the skin. The dif- 
ferent parts of a vertebra are so put 
together as to leave an open space 
near the centre. In the backbone, 
the vertebrae lit neatly one above the 
other, so that when all are in place, 
the holes or spaces come together 
and form a long tube, the spinal 
canal. 
Fig. 6.-A Vertebra. 
16. General Facts about the 
Bones.—The only movable bone in 
the head (Fig. 7) is the lower jawbone, which works 
up and down when the mouth shuts and opens. The 
Pig. 5. 
The Spinal Column. 24 
FIRST LESSONS IN PHYSIOLOGY. 
bony chest is largely formed by long hoops of bone, 
called ribs, which run around from the backbone to 
the breast-bone in front. At the top and front of the 
chest on each side is a slender collar-bone, while at the 
top and behind is a broad, thin, three-sided shoulder- 
blade. In the lower part of the trunk is a basin or 
pelvis made up of several heavy bones. The bones 
of both the upper and lower limbs differ in size, but 
otherwise are similar. One long heavy bone is found 
in the upper arm and in the thigh, while the forearm 
and the leg below the 
knee contain each 
two bones. The wrist 
is composed of eight 
small bones, in two 
rows of four each. In 
the palm of the hand 
and in the fingers we 
have a series of slen- 
der bones parallel to 
each other. The bones 
of the upper extrem- 
ity are shown in Fig- 
ures 8, 9, and 10. 
The instep and heel 
are made up of seven bones. In the middle of the 
foot are five bones, so arranged with reference to the 
bones of the heel and the toes, as to give the foot the 
form of an arch. This arched form is represented in 
Fig. 11. This arching serves to break the force of 
falls and jars and to give spring to the step. In the 
toes, as in the fingers. a series of slender bones is 
Fig. 7-The Skull. THE BONES. 
25 
found. A small, thick bone, shaped somewhat like a 
Fig. 8. 
Bones of the Arm. 
Fig. 9. 
Bones of the Fore*arm. 
Fig. 10. 
Bones of the Wrist and Hand. 
Fig, 11.—The Bones of the Foot. 
chestnut, and called the knee-pan, passes over the knee- 
joint in front. 26 
FIRST LESSONS IN PHYSIOLOGY. 
17. Movements of the Spine.—Although we have 
this long bony pillar up our backs, it is surprising how 
readily we can bend and turn and twist. It is also 
wonderful how perfectly this column bears the weight 
of the head and protects the contents of the skull 
and spinal canal from blows and shocks. One bone 
does not rest upon the other in the spinal column of 
the living person, but between the vertebrae are little 
cushions of gristle or cartilage, which help to prevent 
jarring in sudden movements of the body. In front, 
behind, between, and around the separate bones of the 
column are bands or ligaments, which hold the ver- 
tebrae together, and yet, being elastic, they stretch 
more or less, and thus permit considerable freedom of 
motion. 
18. Movements of the Head.—The first two ver- 
tebrae at the top of the spine have peculiar shapes. 
In the middle of the first is a ring or hole. From 
the second a tooth or peg arises. This passes upwards 
through the hole in the first, and upon it the head 
turns and moves as upon a pivot. The first vertebra 
is called the atlas. According to an ancient fable the 
god Atlas carried the globe his shoulders, and 
hence the name atlas has been given to this bone 
which supports the globe-shaped head. The second 
bone is called the axis, an axis being the straight 
line or rod on which a revolving body turns. 
19. Uses of the Bones.—The bones preserve the 
general shape of the body. As we have seen, the skele- 
ton is the framework of the body. The soft parts 
cling to the supporting bones. The bones enable THE BONES. 
27 
us to stand erect and to perform the numerous move- 
ments of the body. They form grooves, canals, and 
cavities in which important organs are lodged and 
shielded. These bony passage-ways and compartments 
are beautifully adapted for the purposes of protection. 
The skull is arched or rounded, and will not break 
easily when struck, thus affording the best protection 
to the brain. The spinal column is strong and rugged, 
that it may play well its important part in guarding 
the delicate spinal cord and spinal nerves. The heart 
and lungs are free to move, and yet are well protected 
by the strong, elastic, bony chest. 
20. One-Sided Development.—Most people are 
“ right-handed.” Children are usually taught to 
use the right hand in preference to the left. The 
wisdom of this instruction is doubtful. Every child 
should learn to use both hands. The bones of the 
right side of the body become larger than those of 
the left, because the limbs of the former are used 
so much more than those of the latter. We should, 
as far as possible, give both sides of the body, bones 
and everything else, an equal chance for development. 
21. Diseases of the Bones.—In order that the 
bones shall be strong and healthy the animal and 
mineral matter which they contain must be in proper 
proportion. If they contain too much animal matter 
they will be too soft, and sometimes will actually bend 
out of shape. If they contain too much mineral mat- 
ter they will be too brittle. The disease from which 
one suffers when the bones contain too much animal 
and too little mineral matter is called rickets or rachitis, 28 
FIRST LESSONS IN PHYSIOLOGY. 
which term is derived from a Greek word meaning 
the “ spine.” The disease sometimes shows itself by 
some form of curvature of the spine; sometimes by 
bow-legs and badly-shaped arms and ribs. The best 
remedies for such a condition are life in the open air, 
plenty of nutritious food, cod-liver oil, and prepara- 
tions containing lime. 
22. Softness of the Bones in Early Life.—In in- 
fancy and childhood even healthy bones are much 
softer than in adult life, and they may be bent out of 
shape if they are used too soon or in an improper way. 
Some of the forms of spinal curvature are caused by 
children and young people holding their bodies too 
long in certain positions. Bending over too much 
when reading, writing, sewing, or doing similar work, 
will give the bones of the spine an unnatural twist. 
In youth the bones of the feet are sometimes pressed 
out of shape and position by tight shoes. 
23. Brittleness of the Bones in Old Age.—In old 
age the mineral matter of the bones, which is chiefly 
a form of lime, becomes excessive. They lose much 
of their toughness and become brittle. Old people 
require to be more careful of their movements as they 
are in more danger of breaking their bones than the 
young. In some diseases a similar brittleness of the 
bones is produced by an excess of mineral substance. 
24. Broken Bones.—When a bone is broken, and 
surgical help cannot at once be obtained, the whole 
limb should be carefully supported, and the patient 
kept perfectly quiet. When a broken limb is prop- SYLLAB US. 
29 
erly set it heals by a regular process. A soft sub- 
stance is first thrown out between and around the ends 
of the fragments. This gradually, but very slowly, 
becomes harder and harder. If the bone is not kept 
at rest, the process of healing and hardening is inter- 
fered with, and hence surgeons use supporting splints, 
and require the limb to be kept at rest. 
Syllabus. 
Every animal has a shape of its own, which depends mainly upon 
its skeleton. The word skeleton means a dried-up body. As usually 
seen, it consists of bones which have been cleaned, dried, and put 
together with wires. 
The skeleton contains about two hundred and eight bones, of 
which thirty are in the head, fifty-four in the trunk, and one hun- 
dred and twenty-four in' the limbs. 
Some of the hones which are separate in the infant, or little child, 
grow together as age advances. 
Bone is firm and dense outside, but it has canals and cavities 
within, which give it lightness as well as strength. 
Bones are composed of both animal and mineral matter. The 
mineral matter can be dissolved by muriatic acid; the animal mat- 
ter can be burned out. 
The backbone is a strong, bony column reaching downwards from 
the skull. It is composed of many little bones called vertebra, which 
fit neatly one above the other. 
When the vertebrae are all in place, holes or spaces in them come 
together so as to form a long tube,—the spinal canal. 
The lower jaw-bone is the only movable bone in the head. 
The bony chest is largely formed by ribs, which run around from 
the backbone to the breast-bone. 
At the top and front of the chest, on each side, is a slender collar- 
bone ; at the top, behind, is a broad, thin, three-sided shoulder-blade. 
In the lower part of the trunk is a basin, or pelvis, made up of 
several heavy bones. 
One long heavy bone is found in the upper arm and in the thigh, 30 
FIRST LESSONS IN PHYSIOLOGY. 
while the forearm and the leg below the knee contain each two 
bones. 
The wrist is composed of eight small bones, in two rows of four 
each. 
In the palm of the hand, and in the fingers, are a series of slender 
bones parallel to each other. Similar bones are found in the toes. 
The instep and heel are made up of seven hones. 
The bones in the middle of the foot are so arranged as to give the 
foot the form of an arch. 
A small, thick bone, called the knee-pan, passes over the knee-joint 
in front. 
Between the vertebrae are little cushions of gristle or cartilage, 
which help to prevent jarring in sudden movements of the body. 
Elastic bands or ligaments hold the vertebra together. They 
stretch more or less, and thus permit considerable freedom of move- 
ment. 
In the middle of the first vertebra is a ring or hole. Prom the 
second a tooth or peg arises, and passes upward through the hole in 
the first. Upon this the head turns and moves, as upon a pivot. 
The bones preserve the general shape of the body. The soft parts 
cling to them. They enable us to stand erect, and perform the 
numerous movements of the body. They form grooves, canals, and 
cavities for important organs. 
We should, as far as possible, give both sides of the body, bones, 
and everything else, an equal chance for development. 
If bones contain too much animal matter, they will be too soft; 
if they contain too much mineral matter, they will be too brittle. 
The disease from which one suffers when the bones contain too 
much animal and too little mineral matter is called rickets. 
Rickets shows itself by curvature of the spine ; sometimes by bow- 
legs or badly-shaped arms and ribs. It should be treated with 
nutritious food, cod-liver oil, and preparations containing lime, and 
the patients should be kept in the open air as much as possible. 
In early life even healthy bones are somewhat soft, and may be 
bent out of shape if they are used too soon or in an improper way. 
In old age, and in some diseases, the mineral matter of bones 
becomes excessive. The bones lose much of their toughness, a,nd 
become brittle. QUESTIONS FOR REVIEW. 
31 
Questions for Review. 
Upon what does the shape of an animal mainly depend ? 
What is the meaning of the word skeleton? 
As usually seen, of what does it consist? 
How many bones does the skeleton contain ? 
How many bones in the head, in the trunk, and in the limbs ? 
Why does the number vary at different ages? 
What is the structure of the outer portion of a bone ? 
What does a bone contain within ? 
What is the outer substance of bone called ? 
What name is applied to the inner substance ? 
Of what two kinds of matter is bone composed ? 
Describe an experiment for dissolving the mineral matter. 
How can the animal matter be removed ? 
What purpose is served by the backbone ? 
Describe the backbone. 
What are the vertebrae ? Describe a vertebra. 
How is the spinal canal formed ? 
What bone in the head is movable ? 
How is the bony chest formed ? 
Describe the situation of the collar-bone and shoulder-blade. 
What is found in the lower part of the trunk ? 
How many bones are present in the arm, thigh, forearm, and leg? 
Of how many bones is the wrist composed ? 
What bones are found in the hand and fingers ? 
How many bones are in the instep and heel ? 
How many bones are in the middle of the foot? 
How are they arranged ? 
What bones are found in the toes ? 
What is the knee-pan? 
What is present between the vertebrae? 
How are the vertebrae held together ? 
Describe the first two vertebrae at the top of the spine. 
What is the name of the first vertebra ? Why was it so named ? 
What is the name of the second vertebra? 
What was the origin of this name ? 
What are some of the uses of the bones ? 
What is the shape of the skull? FIRST LESSONS IN PHYSIOLOGY. 
Why is the skull arched or rounded ? 
How is the spinal column built ? 
How are the heart and lungs protected? 
Why do the bones of the right side become larger than those of 
the left? 
How should the two sides of the body be developed ? 
What is necessary in order that the bones shall be strong and 
healthy ? 
What is rickets or rachitis ? 
How does the disease show itself? 
What are the best remedies for rickets ? 
Why can even healthy bones be bent out of shape in early life ? 
Mention some of the ways in which deformity of the bones can be 
produced. 
Why are the bones of the aged brittle ? 
Why should old people be careful of their movements ? 
What effect has certain diseases upon the bones ? CHAPTER III. 
THE JOINTS. 
25. A Joint.—A joint is the arrangement which 
is found where the ends of two or more bones come 
together. The ends of the bones are smooth and 
moist. This can be seen by looking at the knuckle 
of a leg of mutton before it is cooked. 
26. The Joint Juice or Synovial Fluid.—The ends 
of the bones are coated with slippery gristle or carti- 
lage, which is kept constantly wet by a thick, sticky 
fluid, which is sometimes called “joint juice,” or “joint 
oil.” It has, however, a higher-sounding name, syno- 
vial fluid,, a term made up from Greek words which 
mean “ like the white of an egg.” It is poured out 
by a little sac or bladder which is placed between 
the ends of the bones. In this way the joint keeps 
itself well oiled. 
27. Immovable Joints.—In the head, all the joints 
except those of the lower jaw are immovable. Most 
of the bones of the skull have saw-like edges, so that 
one dove-tails into another very firmly. Some of the 34 
FIRST LESSONS IN PHYSIOLOGY. 
joints in the lower part of the trunk are also immova- 
ble. Some joints, as those of the spinal column, allow 
a little motion. Between the bones which form the 
immovable joints is a layer of tough tissue or mem- 
brane. When a bone is struck a hard blow the shock 
causes it to vibrate and sometimes to break. The 
tough membrane between the bones serves to deaden 
this shock and prevent breaking. 
28. Movable Joints.—Movable joints are those 
which allow motion of one part of the body upon 
another. They differ according to the 
kind of motion which they permit. A 
hinge-joint, such as is found at the elbow, 
knee, or ankle allows a forward and back- 
ward movement, like that of a door on its 
hinges. Figure 12 represents the elbow- 
joint. A ball-and-socket joint is .one in 
which a rounded surface on the end of one 
bone moves in a cup in another. Joints 
of this sort are found at the shoulder and 
hip. A pivot-joint is formed by one 
bone, shaped like a peg or pivot, fitting into a hole 
in another bone. The best example of this is fur- 
nished by the two bones at the top of the spinal 
column. 
Fig. 12. 
The Elbow-Joint. 
29. Ligaments of the Joints.—Bands or slips, 
called liyaments, from the Latin word ligare, “ to bind,” 
pass from one bone to the other at the joints. These 
ligaments prevent the bones from getting too far apart. 
They tie them together loosely, so that they can move 
upon each other to a certain extent. The sac or THE JOINTS. 
35 
bladder which secretes the “joint-juice,” or synovial 
fluid, also acts as a ligament, one side of it being 
attached around the end of one bone, and the other 
around the extremity of the opposite bone. 
30. Pressure of the Air upon the Joints.—The air, 
although invisible, is a great force and is always 
exerting pressure. It is supposed that this pressure 
of the air assists the ligaments in keeping the bones 
Fig. 13.—Section of the Hip-Joint. 
in place at the joints. The thigh-bone at the hip- 
joint is certainly kept in position partly by the pres- 
sure of the atmosphere. Figure 18 represents a 
section of the hip-joint. The head of the thigh-bone 
fits very closely in the socket. The cavity of the joint 
is, moreover, completely closed by the synovial sac. 
If, while the bones are in position, a hole be bored 36 
FIRST LESSONS IN PHYSIOLOGY. 
into the joint, so as to allow air to get into its cavity, 
the head of the- thigh-bone will at once fall partly out 
of the socket, the pressure of the air now acting both 
from within and without. 
31. Unusual Motion in Joints.—Some people have 
great freedom of motion in their joints. They can, 
for instance, bend their hands backwards, and their 
fingers backwards and sidewise. They are probably 
able to do this because the joint-ligaments are longer 
than usual, and hence allow more separation of the 
ends of the bones. Children for sport sometimes pull 
their fingers to “ make their joints crack.” This is a 
dangerous habit, for by so doing they may overstretch 
the ligaments of the joints, and cause an injury which 
it will be hard to remedy. 
32. Uses of the Joints.—Without our numerous 
movable joints we would be stiff and awkward crea- 
tures. The useful and graceful movements which we 
can now make would be impossible. The joints are 
so arranged as to allow each movable part of the body 
to perform its movements to the best advantage. At 
the elbow a forward and backward movement of the 
forearm upon the arm is all that is permitted by the 
hinge-joint, but this is all that is required to make the 
arm most useful. The cup of the ball-and-socket-joint 
at the shoulder is shallow, and movements of the arm 
can be made in almost any direction. The socket of 
the hip-joint is deep, an arrangement which allows 
less freedom of motion, but gives greater firmness and 
security. The pivot-joint of the spinal column is sup- 
plied with ligaments which permit the head to move SYLLABUS. 
37 
from side to side, but not far enough in any direction 
to damage the delicate nervous matter within the skull 
and spine. The superiority of man over other animals 
is largely due to the number and the perfection of the 
movements which can be performed by the hand and 
fingers; and these movements are made possible by 
numerous joints. 
33. Injuries of the Joints.—Sudden jars, falls, or 
blows may wrench a joint or put it out of place. The 
violent twisting and tearing of the ligaments and soft 
parts about a joint is called a sprain. A joint is put 
out of place, or dislocated, when the ends of the bones, 
which naturally work upon each other, are forced apart. 
Sometimes in ball-and-socket-joints the smooth round 
head of the bone is pulled entirely out of the socket 
in which it should always play. Remembering these 
facts, children should not be too rough in their sports. 
Injured joints should be promptly attended to or per- 
manent mischief may result. Dislocations should be 
set as soon as possible. 
Syllabus. 
A joint is the arrangement found where the ends of two or more 
bones come together. The ends of the bones are smooth and moist. 
The ends of the bones are coated with slippery gristle, which is 
kept constantly wet by the joint-juice, or synovial fluid. 
The synovial fluid is poured out by a little sac or bladder, which 
is placed between the ends of the bones. 
In the head, all the joints except those of the lower jaw are im- 
movable, 
Some of the joints in the lower part of the trunk are also immov- 
able. FIRST LESSONS IN PHYSIOLOGY. 
Some joints, as those of the spinal column, allow a little motion. 
A tough membrane between the bones which form the immovable 
joints serves to deaden the shock given to bones when they are struck. 
Movable joints are those which allow motion. They differ accord- 
ing to the kind of motion which they permit. 
A hinge-joint, such as is found at the elbow, knee, or ankle, allows 
a forward and backward movement. 
A ball-and-socket-joint is one in which a rounded surface moves 
in a cup. Such joints are found at the shoulder and hip. 
A pivot-joint, of which the best example is found at the top of the 
spinal column, is formed by a peg of bone, fitting into a hole in 
another bone. 
Ligaments pass from one bone to the other at the joints, and pre- 
vent the bones from getting too far apart. 
The sac which secretes the joint-juice acts also as a ligament. 
The pressure of the air assists the ligaments in keeping the bones 
in place. 
The thigh-bone at the hip-joint is certainly kept in position partly 
by the pressure of the atmosphere. 
If air is allowed to get into the cavity of the hip-joint, the head 
of the thigh-bone will at once fall partly out of its socket. 
Some people have great freedom of motion in their joints,' because 
the joint-ligaments are longer than usual. 
Pulling the fingers to “make the joints crack” is a dangerous 
habit, which may cause overstretching of the ligaments of the joints. 
A joint is so arranged as to allow each movable part to perform its 
movements to the best advantage. 
At the elbow a forward and backward movement is that which is 
most required and allowed. 
At the shoulder the cup of the ball-and-socket-joint is shallow to 
allow of movements in many directions ; at the hip it is deep to give 
greater firmness and security where these qualities are needed. 
The pivot-joint of the spinal column is supplied with strong liga- 
ments, which permit the head to move just as far as it is safe for it 
to go. 
The superiority of man over other animals is largely due to his 
numerous joints. 
Sudden jars, falls or blows may cause sprains or dislocations. 
Injured joints should be promptly treated. QUESTIONS FOR REVIEW. 
39 
Questions for Review. 
What is a joint? 
With what are the ends of the bones coated? 
How are they kept moist? 
What is the scientific name of the joint-juice? 
From what is the term “synovial” derived? 
By what is the synovial fluid secreted ? 
What are the only movable joints of the head? 
How are most of the bones of the skull united ? 
Where, besides in the head, are immovable joints found? 
How much motion do the joints of the spinal column allow? 
What is present between the bones which form the immovable 
joints? 
What is the effect of striking a bone a hard blow ? 
What purpose does the tough membrane between the bones serve ? 
What are movable joints ? How do they differ ? 
What is a hinge-joint? Where are hinge-joints found ? 
What is a ball-and-socket-joint? What joints are of this kind? 
What is a pivot-joint? What is the best example of a pivot-joint? 
What are the ligaments of the joints? 
From what is the word ligament derived ? 
How do the ligaments of the joints act? 
How does the sac or bladder which secretes the joint-juice act? 
What assists the ligaments in keeping the bones in place? 
How does the head of the thigh-bone fit in its socket? 
How is the cavity of the hip-joint closed? 
How can it be proved by experiment that the pressure of the air 
helps to keep the hip-joint in place ? 
Why have some people greater freedom of motion in their joints 
than others ? 
What dangerous habit have some children ? Why ? 
How are the joints arranged with reference to movements? 
What movement is permitted at the elbow ? 
Why is the socket at the shoulder-joint shallow? 
Why is the socket of the hip-joint deep ? 
How is the pivot-joint in the neck strengthened? 
To what is the superiority of man over other animals largely due ? 
What is a sprain ? What is a dislocation ? 
Why should injured joints be attended to promptly? CHAPTER IV. 
MUSCLES AND MOVEMENTS. 
34. Motion.—Motion exists everywhere. Every 
living animal is in some way blessed with motion. 
Sometimes a little motion is all that tells us that an 
animal is alive. We can study the forms of motion 
in animals in different ways. Sometimes the study is 
about the movement of the whole animal from place 
to place, as of a man walking, a fish swimming, or 
a bird flying; this we call locomotion. Sometimes 
it is about the movement of a part of the animal, 
as of a limb in striking or kicking, or of the eye 
when it turns from side to side. Sometimes it is 
about the movements of fluids or gases, as of blood 
in the vessels, and of the air in the lungs. 
35. The Machinery of the Body. — The body 
may be compared to a machine. Some machines are 
simple, both as regards the manner in which they are 
made and the work they have to do; others are com- 
plex, have more parts, and serve more purposes. The 
human body resembles the latter class. Mechanics is 
the science of machinery, and in studying the body MUSCLES AND MOVEMENTS. 
41 
we are, therefore, learning lessons in animal mechanics. 
The limbs have their levers and cords ; the jaw moves 
up and down on its hinges; the blood is distributed 
by its pump and pipes; the lungs act as bellows, 
drawing in and forcing out air; the food is pushed 
onward by the movement of the food-canal. For 
eating, drinking, seeing, hearing, thinking, and all 
other functions, a special machinery is provided. 
All these functions in some way involve motion. 
36. Movements of the Limbs.—We shall study 
in this Chapter chiefly about the machinery and move- 
ments of the limbs. Compared with some of the fine 
changes which are going on in the hidden places of 
the body, these movements are coarse and rough; and 
yet they are wonderful when deeply studied. The 
movements of our limbs are directly brought about 
by the help of bones and joints, which have just 
been considered, and of the muscles, wdiich we shall 
now study. The bones, and everything which clings 
to them, are moved by the muscles. The joints per- 
mit this motion. The muscles are the motors, or 
movers; in some way they do the pulling and push- 
ing which cause the motion. 
37. Muscle and the Muscles of the Body.— 
Muscle is the flesh or lean meat. When we eat lean 
beefsteak or mutton we are eating muscle. It com- 
prises a large part of the human body. It is arranged 
in many different masses or bundles, which form the 
muscles, of which the body contains more than five 
hundred. Fig. 14 exhibits the principal muscles of 
the front of the body. FIRST LESSONS IN PHYSIOLOGY. 
Fig. 14.—Frincipal Muscles of the Front of the Body. MUSCLES AND MOVEMENTS. 
43 
38. The Names of the Muscles.—Each muscle 
has its own name, which has been given to it because 
of something peculiar in its shape, size, or appear- 
ance. The pectoral muscle is the muscle of the breast 
or chest, pectus being the Latin for “breast” or 
“ chest.” Biceps means “ two-headed,” and triceps, 
“three-headed,” the first of these muscles beginning in 
two parts and the second in three. The large, thick 
muscle covering the shoulder-joint is called the deltoid, 
because of its likeness to the Greek letter a {delta). 
The oblique muscles have their fibres running in a 
slanting direction; while the fibres of the recti or 
straight muscles run more directly. The meaning of 
the word sartorius is, “ belonging to a tailor,” and the 
muscle crossing the thigh, which is the longest in the 
body, is so named because a tailor uses it in crossing 
his legs. The internal vastus muscle is of “vast” 
size. The soleus muscle, forming part of the “calf” 
of the leg, is so termed from a supposed resemblance 
to the sole of a foot or shoe. 
39. The Different Parts of a Muscle.—A muscle 
has a middle fleshy part, which is called the body, and 
two ends of tough, whitish material, called the sinews 
or tendons. Sometimes these tendons are short, some- 
times they are long, sometimes they are round, some- 
times flat. They are always strong. 
40. The Tendon of Achilles.—The strongest ten- 
don of the body is the tendon of Achilles (as shown in 
Fig. 11, page 25, and Fig. 14, page 42), which runs 
from the muscles of the calf to the heel. This tendon 
received its name in a curious way. The story is that 44 
FIRST LESSONS IN PHYSIOLOGY. 
Achilles, a famous Greek hero, when a babe, was 
dipped by his mother into the river Styx, the waters 
of which rendered the body invulnerable. When the 
dipping took place the child was held by the heel. 
Achilles passed unharmed through many wars, but 
finally came to his death from an arrow-wound in 
the heel. Anatomists, therefore, have called this ten- 
don of the heel the tendon of Achilles. 
41. The Structure of Muscle.—The body, or 
fleshy part, of the muscle is made up of a large num- 
ber of strings or fibres of flesh, running in the same 
direction. These are held together by a 
web of connective tissue, and they are 
arranged in bundles of different sizes, as 
shown in Fig. 15. 
42. Contraction of Muscles. — All 
muscle can contract or shorten itself. As 
muscles contract they become thicker; 
they spread out sidewise. Contractility 
belongs to muscle; it is one of its prop- 
erties. Muscles can be made to contract in various 
ways, for instance, by applying to them a current of 
electricity. When the arm, leg, hand, foot, mouth or 
eyelid, or any other part, is moved, it is through a mus- 
cular contraction. 
Pig. 15.—Muscle 
slightly Magnified. 
43. The Biceps Muscle.—Let us select one muscle 
and study its actions. When the forearm is bent, in 
bringing the hand up towards the shoulder, a distinct 
bulging occurs between the elbow and the shoulder. 
This is caused by the contraction of the large muscle 
on the front of the arm, called the biceps. Two cords MUSCLES AND MOVEMENTS. 
45 
go up from the body of the muscle to points above. 
A single cord goes to one of the bones of the fore- 
arm. The forearm can move freely on the arm at the 
elbow-joint, both of its bones moving together. The 
contraction or shortening of the biceps muscle must 
therefore pull the forearm up towards the arm, giving 
an illustration of the lever. 
44. Levers.—It may help us to understand better 
the movements of the limbs if we recall here a few facts 
about levers. A lever is simply a lifter or raiser. To 
carry out the act of lifting or raising, power must be 
used upon a weight; and the lever must have a place 
to rest, and a point called a prop or fulcrum, about 
which it can move. Levers are of three orders. In 
the first order the fulcrum is between the power, 
Fig, 16—Lever of the First Order. 
and the weight (Fig. 16). A crowbar applied to lift 
a stone is a lever of this kind. In the second, the 
weight is between the power and the fulcrum (Fig. 17). 
An oar is a lever of this sort. In the third, the power 
acts between the fulcrum and the weight (Fig. 18). 
mi. _ t— ji_i. • ’.l-i- _ |ong ro(j 0ften makes it a lever 
of this kind. He rests one 
end of the rod on the ground 
and thus gets his fulcrum; 
then, supporting it with one 
hand he applies his 'power with 
the other, and swings around the weight, which is made 
up of 'rod, line, and fish. 
Fig. 17.—Lever of the Second Order. 
Fig. 18. 
Lever of the Third Order. 46 
FIRST LESSONS IN PHYSIOLOGY. 
45. Levers of the Third Order in the Limbs.— 
In our limbs we have chiefly levers of the third order. 
Such a lever is beautifully illustrated in the move- 
ment of the forearm as shown in Fig. 19. The ful- 
Fig, 19.—Lever of the Third Order in the Limhs. 
crum is at the elbow; the weight is made up of the 
weight of the bones of the forearm and hand and the 
ball which is grasped by the latter; the power is in 
the biceps or flexor muscle, and is applied where its 
lower end is fastened to one of the bones of the forearm, 
and therefore between the fulcrum and the weight. 
46. Action of the Muscles in General.—Just as 
the biceps muscle has the power of contracting, so 
muscles everywhere have the power of contracting 
and producing movement. In contracting they act 
on the bones as on levers. Some organs, as the heart 
and blood-vessels, simply squeeze together as they 
contract. SYLLABUS. 
Syllabus. 
Motion exists everywhere. 
Locomotion is movement from place to place, as of a man walk- 
ing, a fish swimming, or a bird flying. 
The body may be compared to a complex machine. 
Mechanics is the science of machinery, and in studying the body 
we are learning lessons in animal mechanics. 
For all the functions of the body a special machinery is provided. 
The movements of our limbs are directly brought about by the 
help of bones, joints, and muscles. 
The muscles are the motors or movers. 
Muscle is the flesh or lean meat. 
Muscle is arranged in masses or bundles, which form the muscles, 
of which the body contains more than five hundred. 
The pectoral muscle is the muscle of the breast or chest. 
Biceps means “two-headed,” and triceps “three-headed,” the first 
of these muscles beginning in two parts and the second in three. 
The deltoid muscle is so called because of its likeness to the Greek 
letter a (delta). 
The fibres of the oblique muscles are slanting, those of the recti 
or straight muscles are straight. 
Sartorius means “ belonging to a tailor.” A tailor uses the sarto- 
rius muscle in crossing his legs. 
The internal vastus muscle is of vast size. 
The soleus muscle is so termed from a supposed resemblance to the 
sole of a foot or shoe. 
A muscle has a middle fleshy part called the body, and two ends 
of tough, whitish material, called sinews or tendons. 
The strongest tendon of the body is the tendon of Achilles, which 
runs from the muscles of the calf to the heel. This tendon received 
its name from Achilles, a famous Greek hero. 
The body of a muscle is made up of a large number of fibres of 
flesh running in the same direction. These are arranged in bundles 
of different sizes. 
Contractility is one of the properties of muscle. When a part of 
the body is moved it is through a muscular contraction. 
The forearm is bent on the arm by the contraction of the biceps 
muscle on the front of the arm. 48 
FIRST LESSONS IN PHYSIOLOGY. 
The forearm moves freely on the arm at the elbow-joint, the con- 
traction or shortening of the biceps pulling the forearm up towards 
the arm. 
We have in the movement of the forearm on the arm an illustra- 
tion of the lever or lifter. 
Levers are of three orders. In the first the fulcrum is between 
the power and the weight; in the second, the weight is between the 
power and the fulcrum ; in the third, the power acts between the ful- 
crum and the weight. 
Our limbs chiefly contain levers of the third order. 
In the movement of the forearm on the arm, the fulcrum is at the 
elbow; the weight is made up of the bones of the forearm and hand, 
and whatever is grasped by the latter; the power is in the biceps, 
and is applied where its lower end is fastened to one of the hones of 
the forearm, and therefore between the fulcrum and the weight. 
Just as the biceps muscle has the power of contracting, so muscles 
everywhere have the power of contracting and producing move- 
ments. 
In contracting, the muscles act on the bones as on levers. 
Some organs, as the heart and blood-vessels, simply squeeze to- 
gether as the muscles contract. 
Questions for Review, 
What is said about the existence of motion ? 
What alone sometimes tells us that an animal is alive? 
What is locomotion ? Give illustrations. 
What movements of the parts of an animal do we study ? 
What movements of fluids and gases do we study? 
To what may the body be compared ? 
What is mechanics ? What is animal mechanics ? 
Give some illustrations of the machinery of the body. 
What do all of the functions of the body involve? 
How are the movements of the limbs brought about ? 
What do the muscles do ? 
What do the joints permit ? 
What are the muscles with reference to motion ? 
What is muscle ? 
How are the muscles formed ? QUESTIONS FOR REVIEW. 
How many muscles does the body contain ? 
How did many of the muscles receive their names ? 
Define and give the derivation of the words pectoral, biceps, tri- 
ceps, deltoid, recti, sartorius, vastus, and soleus. 
What are the different parts of a muscle ? 
Which is the strongest tendon of the body ? 
Relate the story about the way in which this tendon received its 
name. 
Of what is the fleshy part of muscle composed ? 
How are the muscular fibres held together and arranged? 
What property is possessed by all muscle ? 
As muscles contract, how do they change in shape ? 
Mention one way in which muscles can be made to contract. 
Give illustrations of movements due to muscular contraction. 
When the forearm is bent on the arm what occurs between the 
elbow and shoulder ? What causes the bulging ? 
How is the biceps muscle attached above and below ? 
How does the forearm move on the arm ? 
Of what have we an illustration in this movement? 
What is a lever ? Levers are of how many orders ? 
Explain the three orders of levers. 
Give an illustration of each order. 
What kind of levers are chiefly found in the limbs ? 
In what movement is a lever of the third order beautifully illus- 
trated ? 
In the movement of the forearm on the arm, where is the fulcrum ? 
What constitutes the weight ? 
Where is the power ? How is it applied ? 
What power have all muscles? 
In contracting, how do they act on the bones ? 
What is the result of the contraction of some organs, as the heart 
and blood-vessels ? CHAPTER V 
MUSCULAR EXERCISE 
47. Exercise.—Any kind of muscular movement 
‘is physical exercise. The term exercise, however, 
is usually applied to the practice of muscular move- 
ments under the control of the will, with the view of 
developing certain parts of the body. The health 
of the body depends largely upon the proper exercise 
of its different parts. 
48. Muscular Exercise and Muscular Contrac- 
tility.—The ability to perform the movements which 
constitute muscular exercise depends upon the property 
of contractility which belongs to muscle. The muscle 
shortens by virtue of its contractility; but the shorten- 
ing cannot continue permanently. The muscle relaxes 
and lengthens again. Shortening and lengthening, or 
contraction and relaxation, follow each other, and thus 
the muscles are exercised. Just as muscular contrac- 
tion may be weak or strong, slow or rapid, simple or 
complicated, so exercise may be greatly varied. MUSCULAR EXERCISE. 
51 
49. Effect of Exercise on Muscle.—If the mus- 
cles are exercised frequently; in other words, if they 
are made to contract again and again, they increase 
in size and strength. We see illustration of this fact 
in the strong right arm of the blacksmith, and in the 
stout back of the porter. If the muscles are not used 
frequently they become small and weak. This is seen 
in those who from choice or necessity do not lead 
physically active lives. In those who suffer from the 
disease called paralysis the muscles waste away. 
50. Effect of Exercise on the Bones.—Strange 
as it may appear, the bones as well as the muscles 
may be changed in size and form by muscular exer- 
cise. The bones, particularly in early life, will yield 
in various ways to the force exerted by the muscles. 
Here and there on the bones are seen little elevations 
at points where the muscles are inserted. They have 
actually been pulled out little by little by the con- 
tractions of the muscles. Bones are sometimes given 
a twist because the muscles on one side are stronger 
than those on the opposite side. In time the whole 
bony framework can be strikingly changed by muscu- 
lar exercise. If this exercise is properly regulated, 
the change will be beneficial, 
51. Effect of Exercise on Various Tissues and 
Organs.—Besides muscle and bone, many tissues and 
organs can be favorably influenced by proper mus- 
cular exercise. As has already been shown, the 
tissues and organs are composed of innumerable 
minute bodies called cells, each of which has the 
power of taking from the blood what it needs to 52 
FIRST LESSONS IN PHYSIOLOGY. 
build up its own kind of tissue. These cells are 
born, die, pass away, and are replaced by others. 
Exercise of any part hastens their decay and death, 
but, at the same time, it gives vigor to the process of 
repair. It calls blood to the part, and new material 
of the best quality takes the place of the worn-out 
particles. The tissue is thus constantly renewed. 
The body is kept fresh and new. While the flow 
of blood is quickened, the organs which pump and 
carry it are strengthened and improved. Breathing 
is largely performed by muscular action, and ex- 
ercise causes the lungs thoroughly to expand and 
contract, and thus to get rid of impure air and replace 
it with that which is fresh and pure. When the brain, 
or thinking organ, is over-worked, muscular exercise 
relieves it by causing the blood to flow to other parts. 
Exercise brings sound sleep by causing a healthful 
fatigue and by calling away excitement from the brain. 
It gives a good appetite by creating a demand for food, 
and at the same time stimulating the organs which 
receive the food and prepare it for the blood. It keeps 
in healthy action the skin and other organs which 
carry off waste matter. 
52. Results of Systematic Exercise.—All mus- 
cular regions of tlie body can be developed, and even 
the height can be increased, by systematic exercise. 
Under such exercise, directed by Maclaren, author of 
a book on Physical Education, a pupil sixteen years 
old, in one year grew from 5 feet 2f inches in height 
to 5 feet 4f inches, and in weight increased from 108 
to 129 pounds. His girth of chest increased from 31 MUSCULAR EXERCISE. 
53 
to 36 inches; his forearm from 8 to 10 inches, and his 
upper arm from 9J to 11J inches. Many remarkable 
accounts of the value of systematic exercise have been 
published. Bryant, the poet, who lived in the enjoy- 
ment of good health to the great age of eighty-four 
years, was in the habit of rising early every morning, 
and going through a series of exercises designed to 
expand the chest, and call into action all the muscles 
and articulations of the body. He also regularly 
walked to and from his place of business, a distance 
of several miles. 
53. Deformities Prevented or Corrected by Exer- 
cise.—Certain deformities are either the direct result 
of insufficient exercise; or, they could by judicious 
exercise be largely remedied. Bounding or drooping 
shoulders, stooping, spinal curvature and a growing to 
one side, are among these deformities. Pigeon-breast, 
in which the breast-bone is too prominent, with flatness 
of the upper ribs; and hollow-chest, in which the 
breast-bone is sunk in, can both be much improved 
by proper exercise in youth. 
54. Fitness, Variety, and Moderation in Exer- 
cise.—Exercise should be regulated by its special 
fitness for the individual. The work of the strong 
should not be given to the weak. Variety should 
not be overlooked. Such exercises in turn should 
be used as will tell favorably on all parts. Exercise 
should never be carried to the point of fatigue or ex- 
haustion. It should be practised for health and not 
for strength alone. Strength will probably result 
from it, but this should not be the primary object. 54 
FIRST LESSONS IN PHYSIOLOGY. 
55. Time for Exercise.—About midway between 
the hours for meals is generally the best time for 
active exercise. In exceptional instances, however, 
when the strength fails rapidly between meals, vigor- 
ous exercise is better undergone in from one to two 
hours after taking food. Just before meal-time, when 
the stomach is empty, and the blood needs replenish- 
ing, much exertion may fatigue and depress the 
system. On the other hand, if the muscles be too 
actively exercised just after a meal the work of the 
stomach may be stopped or disturbed. Exercise in 
the earljT morning before breakfast, when the system 
has been refreshed by sleep, agrees with some people, 
but not with all. The wreak and delicate cannot stand 
it unless they have been gradually trained to it. 
56. A Sound Mind in a Sound Body.—Children 
who attend to their plays, games, and exercises, will 
be better fitted for their indoor mental work. Books 
and studies must not be neglected in the hours ap- 
pointed for them. The aim should be to train both 
mental and physical powers so as to insure a sound 
mind in a sound body. 
Syllabus. 
The term exercise usually is applied to the practice of muscular 
movements under the control of the will, with the view of develop- 
ing certain parts of the body. 
Muscular movements depend upon the property of contractility 
which belongs to muscle. 
Muscles shorten and lengthen, or contract and relax, and thus 
are exercised. SYLLABUS. 
Exercise, like muscular contractions, may be greatly varied. 
If the muscles are exercised frequently, they increase in size and 
strength; if they are not used frequently, they become small and 
weak. 
In those who suffer from paralysis the muscles waste away. 
The bones can be changed in size and form by muscular exercise. 
Here and there on bones are seen little elevations at the points 
where the muscles are inserted. They have been pulled out by the 
contractions of the muscles. 
Bones are sometimes given a twist by overaction of the muscles of 
one side. 
In time muscular exercise can change the whole bony framework. 
Proper exercise will change it for the better. 
Besides muscle and bone, many tissues and organs can be favorably 
influenced by proper muscular exercise. 
The tissues are composed of cells which are born, die, pass away, 
and are replaced by others. 
Exercise hastens the decay and death of these cells, but, at the 
same time, it gives vigor to the process of repair. It calls new blood 
to a part, and renews the youth of the tissue. 
While the flow of blood is quickened, the organs which pump and 
carry the blood, are also strengthened and improved. 
Exercise causes the lungs thoroughly to expand and contract, and 
thus to get rid of impure air and replace it with that which is fresh 
and pure. 
Muscular exercise relieves the brain by causing the blood to flow 
to other parts. 
Exercise brings sound sleep, gives a better appetite, and keeps the 
skin and other organs which carry off waste in healthy action. 
All muscular regions of the body can be developed, and even the 
height can be increased, by systematic exercise. 
Certain deformities are either the direct result of insufficient exer- 
cise, or, at least, by judicious exercise can be largely remedied. 
Rounding or drooping shoulders, stooping, spinal curvature, a 
growing to one side, pigeon-breast, and hollow-chest, are among 
these deformities. 
Exercise should always be in fitness, variety, and moderation. It 
should be practised for health and not for strength alone. 
About midway between the hours for meals is generally the best 
time for active exercise. 56 
FIRST LESSONS IN PHYSIOLOGY. 
Exercise in the early morning before breakfast, when the system 
has been refreshed by sleep, agrees with some people, but not with all. 
Children who attend to their plays, games, and exercises, will be 
better fitted for their indoor mental work. Books and studies must 
not be neglected. 
Questions for Review. 
What is physical exercise ? 
To what is the term exercise usually applied ? 
Upon what does the health of the body largely depend ? 
Upon what property does muscular exercise depend ? 
Explain how muscles are exercised by virtue of their contractility. 
What effect has frequent exercise on the muscles ? Give illustra- 
tions. 
What is the effect if muscles are not used frequently? 
In paralysis, what happens to the muscles? 
What effect has exercise on the bones ? 
What causes some of the elevations seen on bones ? 
How are bones sometimes given a twist to one side ? 
What is said of the effect of exercise on the whole bony frame- 
work ? 
Besides muscle and bone, can other tissues and organs be influenced 
by exercise ? 
Of what are the tissues and organs composed ? 
What power has each cell ? 
What happens to these cells ? 
What is the effect of exercise upon these cells ? 
How does exercise influence the blood ? 
How does it act upon the organs which carry the blood ? 
How is breathing largely performed ? 
What effect has exercise on the lungs and on their supply of air ? 
How does exercise relieve the brain? 
How does it bring sound sleep ? 
How does it give a good appetite ? 
What effect has exercise on the skin and other organs which carry 
off waste ? 
w nat can be accomplished by systematic exercise ? QUESTIONS FOR REVIEW. 
57 
Give an illustration from Maclaren. 
What is related of the poet Bryant ? 
What is said of deformities with reference to exercise ? 
Name some of these deformities. 
By what should exercise be regulated ? 
Should exercise be varied, and how ? 
What is said about fatigue and exhaustion from exercise ? 
Should exercise be for strength ? 
What is usually the best time for active exercise ? 
When the strength fails rapidly between meals, when is exercise 
better undergone ? 
Why is exercise not good just before a meal ? Why not just after 
a meal ? 
What is said about exercise in the early morning ? 
For what will children who exercise be better fitted ? 
Should books and studies be neglected ? 
What should be the aim in education ? CHAPTER VI. 
MODES OF EXERCISE. 
57. Physical Educational Exercises.—Physical 
educational exercises are those conducted in a system- 
atic way with the view of favoring the growth and 
developing the resources of the body. In ancient 
Greece physical exercises were carried on in schools, 
called gymnasia. The term gymnastics is now fre- 
quently applied to regulated exercises of the .body. 
These are usually performed with dumb-bells, clubs, 
weights, wands, bars, rings, ropes, ladders, and similar 
appliances. 
58. Systematic Exercises without Apparatus.— 
Many useful exercises can be performed without any 
apparatus, under a system designed to call out the 
physiological action of the muscles. The term calis- 
thenics, derived from two Greek words, meaning 
“beautiful” and “strength,” is sometimes applied to 
systematic exercise conducted without special appa- 
ratus. In Fig. 20 is a representation of one of the 
positions taken in an exercise of this kind. This 
particular exercise is calculated to develop the chest 
as well as the limbs. MODES OF EXERCISE. 
59 
59. Movements to Promote general Supple- 
ness.— Below is given a series of ten movements in- 
tended to promote general suppleness.* These move- 
ments are a good example of a useful and pleasant 
form of exercise without apparatus. They can be 
readily learned; and, if performed every day, will be 
of great benefit. They can be executed under the 
direction of the teacher, or of some pupil elected to 
the position of “leader.” A wand can be used to beat 
time for the movements. 
Fig, 20.—Calisthenio Exercise, 
Position.— Heels together (as near as the configuration of leg 
will permit); hips thrown back; chest forward; head erect, with 
eyes to front; arms falling easy, with back of hand turned slightly 
to the front. 
Exercise.— From this position bring hands to hips; thumbs back. 
Head.— Turn twice to right, twice to left, once to right, twice to 
* Contributed by Miss Mary E. Allen, of the Boston Gymnasium for 
Ladies and Children, to Wide Awake, for October, 1881, in a series of 
Health Papers prepared for this popular magazine for the young. 60 
FIRST LESSON'S IN PHYSIOLOGY. 
left, once to right, back to front; drop.hands to side and close to a 
fist. 
Shoulder.— Raise right shoulder as high as possible four times, 
raise left four times, raise right and left alternately four times (left 
going up as right comes down), raise both together four times; drop 
hands to side. 
Arm.— Throw right arm to horizontal at side (hand closed tight) 
four times, throw left four times, throw right and left alternately 
four times, throw both together four times, and bring fingers to 
tip of shoulders, upper arm horizontal, elbow pointing to front. 
Forearm.— Throw right forearm to front on the elbow as a pivot, 
until the whole arm is horizontal (closing the hand at the throw), 
four times, throw left four times, throw right and left alternately 
four times, throw both together four times; and carry arms to side, 
horizontally stretched out, with palms up, and fingers closed into a 
fist. 
Wrist.— Turn right fist up as far as possible four times (elbow 
stiff), turn left up four times, turn right and left up alternately 
four times, turn up together four times; and bring arms to hori- 
zontal stretch, front, palms down, fingers together and closed. 
Hand.— Open right hand and stretch every finger four times, 
open left hand four times, open right and left alternately four times, 
open together four times; and bring hands to hips. 
Trunk.— Turn as far as possible to right (holding trunk firm, 
turning face at same time, heels firmly planted), two times, turn to 
left two times, turn to right once, turn to left two times, turn to 
right once; and back to position. 
Thigh—Carry right leg across left (crossing left thigh as far up 
and as close as possible, knees stiff) four times, carry left leg across 
right four times, carry right and left across each other -alternately 
eight times. 
Leg— Raise right leg as high as possible behind (on the knee as 
a pivot) four times (thigh remaining vertical and firm), raise left 
leg four times, raise right and left alternately eight times. 
Foot.— Raise right foot on heel as high as possible four times, 
raise left four times, raise right and left alternately eight times. MODES OF EXERCISE. 
61 
The Position is very important, and the leader should insist upon 
it before the exercise begins. The body should hold the original 
position, with such changes as are indicated, firmly, so that only 
certain muscles are in use at once; thus, when the arm is used, the 
body should be stiff and firm. 
Head Movements should always be slow, but firm, never with 
sudden force. Hence they are taken on the first beat of a measure 
only, or on 1 when counting 1, 2, 3, 4. All other movements are 
done with a spasmodic action, faster, using every other beat of 2-4 
or 4-4 time, or on 1 and 3, in counting 4 That is, the movement 
is made on 1 and the return to position on 3. This exercise can be 
taken to any even 2-4 or 4-4 time, a pot-pourri of popular airs 
being pleasing, or any polka or quickstep. These movements aid 
in bringing muscles under the control of the will, and pronjote ease 
and grace of movement; also, as they force the mind and muscles 
to work together, they are a very valuable stimulus to the mental 
faculties; and, if enthusiastically and earnestly carried out, their 
influence will be felt in all mental work. 
60. Gymnastic Apparatus. — Dumb-bells consist 
of two globular masses, with an 
easily- grasped handle between 
them (Fig. 21). Indian clubs 
are bottle-shaped masses of wood, 
the narrow end being shaped as 
a handle (Fig. 22). Dumb-bells 
of about a pound weight are 
sufficient for children under ten 
years of age. For older children 
they may be somewhat heavier. 
The clubs also should be light. 
It is a mistake to use heavy in- 
struments too soon. The dumb- 
bells and Indian clubs are made 
to describe various curves and movements, 
Pig. 21. 
Dumb-Bell. 
Pig. 22. 
Indian Club. 62 
FIRST LESSONS IN PHYSIOLOGY. 
61. Howto Sit and Stand.— Children should early 
learn to sit and stand properly. Health, strength, and 
gracefulness will thus be acquired. The rule should 
be to hold the body as erect as possible both in sitting 
and standing. School-children often acquire bad habits 
of stooping over, or leaning too much to one side, 
while sitting at their desks or standing for recitations 
and other work. In this way they become ungainly, 
and sometimes deformed. An erect position favors 
the free action of the muscles, and also gives the in- 
ternal organs, such as the heart, lungs, stomach, and 
liver, the fullest opportunity to perform their func- 
tions. 
62. Out-Door Exercises.—The most healthful ex- 
ercises are those which can be performed out of doors. 
Such exercises are both profitable and pleasurable. 
They are sometimes called natural exercises. Among 
the most valuable of these are walking, running, swim- 
ming, rowing, and riding. Leaping, climbing, skating, 
sledding, and similar sports, belong to the same class 
of exercises. 
63. Walking.—Walking is an excellent form of 
exercise, developing many important muscles. It is 
chiefly performed by a series of complicated move- 
ments of the muscles of the legs; but when one walks 
properly, the muscles of the chest, abdomen, and upper 
limbs are also exercised. In walking, the entire 
weight of the body is supported first by one foot 
and then by the other, and thus each limb enjoys 
alternate rest. The trunk should be held erect, the 
head up, and the shoulders well back, while the arms MODES OF EXERCISE. 
63 
are swung to and fro. The foot should be well lifted, 
and the toes turned outwards. In coming down, the 
heel should first touch the ground lightly, then the 
rest of the foot to the toes, the heel being raised by 
the time the toes are reached. The whole foot should 
not be brought down flat upon the ground at once. 
Shoes should be worn broad enough to give every 
part of the foot its natural play. 
64. Running.—Running is not simply fast walking. 
In running, only one foot is on the ground at a time. 
At some instants both feet are entirely removed from 
the ground. It is really a succession of slight leaps. 
It is a valuable exercise both to train the muscles 
and to give lung-power. 
65. Swimming and Bathing.—Swimming is a 
useful exercise for development, and may prove to be 
a valuable art in time of danger. No real good can 
result, and harm may come, from reckless jumping, 
diving, swimming under water, and similar feats of 
daring sometimes indulged in by swimmers. The 
swimmer should not remain too long in the water; 
from a quarter to half an hour is usually enough. 
Surf-bathing serves to harden and strengthen the 
muscles and other organs. It should be practised 
with caution and moderation. 
66. Rowing.—The labor of rowing should not be 
performed too much by the muscles of the back. 
Those who row much sometimes get strong backs, 
while their chests in front remain hollow, and their 
shoulders become rounded. Arms, trunk, and legs 
should all take part in rowing. The stroke should be 64 
FIRST LESSONS IN PHYSIOLOGY. 
made by bringing the body to an upright position, 
and even carrying it a little beyond; 
67. Riding.—Horseback-riding brings into use a 
large number of muscles, in checking and guiding 
the movements of the horse and in preserving the 
equilibrium of the rider. It is a refreshing and in- 
vigorating exercise, adding not only to health and 
strength, but also to courage and presence of mind. 
It is not suitable for the weak, nor for invalids, 
who cannot stand the jarring, or who are unable to 
control even the gentlest animal. Those who are not 
strong should use it in moderation at first, and should 
gradually increase the amount and character of the ex- 
ercise. Heavy riding, such as hunting and steeple- 
chasing, is beneficial to the chest and chest muscles; 
but cannot be practised safely except by those who 
are strong. Carriage-riding is a good form of passive 
exercise, giving fresh air, change of scene, and pleasant 
occupation for the mind, but it does not call for suffi- 
cient muscular exertion to make it a means of devel- 
opment. Velocipede-riding and bicycle-riding have 
recently become popular, and are useful modes of ex- 
ercise if practised in moderation. 
68. Development of Both Sides of the Body by 
Exercise.—The tendency to one-sided development 
was referred to when speaking of the bones. It is 
by exercise that both sides of the body can be given 
an equal chance for development. Defective growth, 
and development of one side, can, with care, be pre- 
vented or remedied. Children should learn to bat, 
to throw, to lift, to use the hammer, etc., with either SYLLABUS. 
65 
hand. Boys should train themselves to kick a ball 
with one foot as well as with the other. Satchels 
and other burdens should not be carried too much in 
one hand or over one shoulder. Writing and sewing 
should be done with either hand. Whenever one 
limb is found to be weaker or less skilful than the 
other, the former should be exercised and trained 
until the inequality is overcome. 
69. Open-Air Games or Recreative Ex'ercises.— 
Open-air games, such, as foot-ball, cricket, base-ball, 
band-ball, tennis, jumping the rope, archery, etc., 
are important means of developing the body and 
keeping it strong and well. Wellington is reported 
to have said that England’s soldiers were made on her 
foot-ball fields. In most of our popular games, as 
foot-ball, cricket, and tennis, the lower limbs have 
much the largest share of work. This should be re- 
membered, and attention given to those games, such 
as archery, hand-ball, etc., in which the upper limbs 
take an active part. Gymnastic exercises afford the 
opportunity of developing the parts which are over- 
looked in work and games. 
Syllabus. 
Physical educational exercises are those conducted in a systematic 
way with the view of favoring the growth and developing the re- 
sources of the body. 
Gymnastics are regulated exercises of the body, usually performed 
with dumb-bells, clubs, etc. 
The term calisthenics is sometimes applied to systematic exercise 
conducted without apparatus. 66 
FIRST LESSONS IN PHYSIOLOGY. 
Dumb-bells are globular masses, with an easily-grasped handle 
between them. Indian clubs are bottle-shaped masses of wood, the 
narrow end being shaped as a handle. 
Both dumb-bells and Indian clubs should be light. 
By learning to sit and stand properly, children acquire health, 
strength, and gracefulness. The rule should be to sit and stand erect. 
School-children often acquire bad habits of stooping over, or lean- 
ing too much to one side. In this way they become ungainly, and 
sometimes deformed. 
An erect position favors the free action of the muscles, and also 
gives the internal organs the fullest opportunity to perform their 
functions. 
The most healthful exercises are those which can be performed 
out of doors: such as walking, running, swimming, rowing, etc. 
Walking, which develops many important muscles, is chiefly per- 
formed by the legs, but the muscles of the chest, abdomen, and upper 
limbs should also be exercised. 
In walking, the weight of the body is supported first by one foot 
and then by the other. The trunk should he held erect, the head up, 
and the shoulders well back, while the arms are swung to and fro. 
The foot should be well lifted, and the toes turned outwards; and, 
in coming down, the heel should first touch the ground lightly, then 
the rest of the foot to the toes. 
Shoes should be broad enough to give every part of the foot full 
Play. 
In running, only one foot is on the ground at a time. Sometimes 
both feet are removed from the ground, running being really a suc- 
cession of slight leaps. 
Bunning trains the muscles and gives lung power. 
No real good can result, and harm may come, from reckless jump- 
ing, diving, swimming under water, and similar feats of daring. 
From a quarter to half an hour is usually long enough for a swim- 
mer to remain in the water. 
Surf-bathing serves to harden and strengthen the muscles and 
other organs. 
The labor of rowing should not be performed too much by the 
muscles of the back; but arms, trunk, and legs should all take part. 
Horseback-riding brings into use a large number of muscles, in 
checking and guiding the movements of the horse, and in preserving 
the equilibrium of the rider. It is not suitable for some invalids. QUESTIONS FOR REVIEW. 
67 
Heavy riding, such as hunting and steeple-chasing, is beneficial to 
the chest and chest-muscles; but cannot be practised safely except by 
those who are strong. 
Carriage-riding is a good form of passive exercise; but it does not 
call for sufficient muscular exertion to make it a means of develop- 
ment. 
Velocipede-riding and bicycle-riding have recently become popu- 
lar, and are useful modes of exercise if practised in moderation. 
By exercise, both sides of the body can be given an equal chance 
for development. 
Whenever one limb is found to be weaker or less skilful than the 
other, the former should be exercised and trained until the inequal- 
ity is overcome. 
Open-air games are important means of developing the body and 
keeping it strong and well. 
In most of our games, the lower limbs, have much the largest share 
of work. Attention should be given to those games, etc., in which 
the upper limbs take an active part. 
Gymnastic exercises afford the opportunity of developing the parts 
which are overlooked in work and games. 
Questions for Review. 
"What are physical educational exercises ? 
What were the ancient Greek schools for physical exercise called ? 
What is meant by gymnastics ? 
With what are gymnastic exercises performed? 
Under what system can exercises be performed without apparatus? 
Define and give the derivation of the term calisthenics. 
What are dumb-bells ? What are Indian clubs ? 
Of what weight should dumb-bells and Indian clubs be for chil- 
dren ? 
How are dumb-bells and Indian clubs used? 
How should children sit and stand ? 
What bad habits are often acquired by school-children ? 
What are some of the results of these bad habits ? 
What does an erect position favor ? 
What are the most healthful of all exercises ? 68 
FIRST LESSONS IN PHYSIOLOGY. 
What are these exercises sometimes called ? Name some of them. 
How is walking chiefly performed ? 
What muscles are exercised when walking is performed properly ? 
In walking, how is the weight of the body supported ? 
How are the different parts of the body held ? 
How should the foot be used ? What sort of shoes should be worn ? 
What is said of the position of the feet in running ? 
What is running in reality? 
What are trained and developed by running ? 
When may swimming prove to be a valuable art? 
What feats sometimes indulged in by swimmers often lead to 
harm? 
About how long should a swimmer remain in water ? 
How is surf-bathing useful ? How should it be practised ? 
What muscles should not be over-used in rowing ? 
What defects of development are often observed in those who row 
much ? 
What portions of the body should take part in rowing ? 
How should the stroke be made? 
How does horseback-riding bring into use the muscles ? 
What can be said of horseback-riding as an exercise ? 
Is it suitable for the weak ? 
What parts are benefited by heavy riding ? 
By whom alone should it be practised ? 
What is said of carriage-riding, velocipede-riding, bicycle-riding ? 
How can both sides of the body be given an equal chance for de- 
velopment ? 
How should children learn to bat, throw, lift, etc.? 
How should a ball be kicked ? 
How should satchels and other burdens be carried? 
How should writing and sewing be done ? 
How can inequalities of the limbs be overcome ? 
Name some open-air games which are important for health and 
development. 
What is Wellington reported to have said? 
Which limbs have the largest share of work in our popular games? 
To what games should especial attention be given ? 
How can the parts overlooked in work and games be developed ? CHAPTER VII. 
THE NERVOUS SYSTEM. 
70. Regulation of the Machinery of the Body.— 
We have seen that the contraction of muscles results 
in the moving of bones and the parts attached to them. 
When the arm is stretched out, or bent upwards, why- 
does it not always so remain? Why does not the leg 
always rest in one position ? Why does not the eye 
always look in one direction ? Our arms, and legs, and 
eyes move in this way or in that, because we wish or 
will them so to move. Something within us directs 
and regulates these movements. All machinery must 
be guided and controlled, or it will do harm rather 
than good. In the case of ordinary machines, as loco- 
motives, steam-ploughs, etc., a human being sees that 
the boilers are properly filled with water, that the fires 
are neither too low nor too high, that the belts and 
wheels are well oiled, that the pipes and valves are all 
in proper condition. The machinery of the body, how- 
ever, is regulated by a part of the machine itself. A 
muscle moves because something tells it to move. This 
order must come from somewhere, and must have a road 
by which to travel. It comes from the brain, and jour- 
neys by way of the spinal cord and nerves to the muscle. 70 
FIRST LESSONS IN PHYSIOLOGY. 
71. The Parts of the Nervous System.—We 
have already learned that some of the bones of the 
head form a case or box, called the skull or cranium, 
and that a long, hollow tube is formed in the backbone, 
and is known as the spinal canal. The skull is filled 
with the organ called the brain, and the spinal canal 
with the spinal cord. The brain and spinal cord are 
connected; they are continuous masses of nervous 
matter. Running off from the brain and spinal cord to 
every part of the body are cords, called the nerves. The 
brain, spinal cord, and nerves, with little gray masses of 
nervous matter called ganglia, which are found here and 
there all over the body, make up the nervous system. 
72. Gray and White Matter of the Nervous 
System.—The nervous system is composed of two 
kinds of tissue, usually spoken of as gray matter and 
white matter. The outside of the brain is made up 
chiefly of gray substance, the interior mainly of white. 
The external portions of the spinal cord are composed 
of white matter, the internal of gray. In the brain 
are some isolated masses of gray matter. Ganglia are 
also scattered here and there throughout the body. 
The nerves are formed of white matter. The gray 
substance of the nervous system is its active portion, 
the source of force or power. The white matter is 
made up of fibres or tracts for conveying impressions. 
These fibres transmit the messages which are sent to 
and fro throughout the body. 
73. Divisions of the Brain.—Fig. 23 is a view of 
the left half of the brain. The large mass above, 
which shows many windings upon its surface, is the THE NERVOUS SYSTEM. 
71 
cerebrum, or greater brain. It comprises about six- 
sevenths of the entire brain. It conforms to the shape 
Fig, 23,—View of the Left Half of the Brain, 
of the skull. Its external surface is made up of con- 
volutions and fissures; that is, instead of being one 
uniform, smooth surface, it is composed of a curious 
system of hills and hollows. Underneath the cere- 
brum is a smaller mass, the cut surface of which pre- 
sents a beautiful tree-like appearance. This is the 
cerebellum, or lesser brain. Two parts, called the me- 
dulla oblongata, or oblong marrow, and pons Varolii, 
are also seen in the picture. The medulla oblongata 
is about one inch long. By some it is regarded as the 
uppermost portion of the spinal cord. Pons Varolii 
means the bridge of Varolius, an Italian anatomist, 
named Yarolius, having first described it. 
74. Membranes of the Brain.—The brain is en- 
closed by two coats or membranes. The outer mem- 72 
FIRST LESSONS IN PHYSIOLOGY. 
brane is called the dura mater, from dura, “ hard,” and 
mater, “ mother.” The name dura was applied to it 
because of its great hardness, or toughness. The term 
mater was given because the ancients had a fanciful 
notion that this membrane was the mother of all the 
other membranes of the body. The inner membrane, 
which is in close contact with the brain, is called the 
pia, mater, or “ delicate mother.” Compared with the 
dura mater it is a very thin and delicate. Some 
anatomists speak of a third membrane, which is called 
the arachnoid, from Greek words meaning “ resem- 
bling a spider’s web.” It is composed of two layers, 
one on the inside of the dura mater, and the other on 
the outside of the pia mater. These so-called layers 
of the arachnoid may be considered as parts of the 
other membranes. 
75. Functions of the Brain.—The parts of the 
brain just described have many divisions and subdi- 
visions, each of which probably has its own special 
use or function. The gray matter of the cerebrum is 
the chief organ of the Mind. It is hard to give a 
definition of mind; but we know it is that something 
within us by means of which we become conscious of 
sensations,, by which we can fix our attention, and by 
which we can remember, think, judge, reason, and 
govern. We know that the cerebrum is the chief 
organ of mind, because when it is injured, diseased, or 
imperfectly developed, the mind is more or less un- 
sound. Different parts of the cerebrum are probably 
concerned with different functions of the mind. In 
one portion we become aware of sensations of touch, THE NERVOUS SYSTEM. 
73 
sight, hearing, taste, smell, pain, etc.; in another, at- 
tention, memory, judgment, reason, and other mental 
faculties, are seated; in still another, are centres from 
which go forth the orders or impulses which cause the 
muscles to move. The functions of the cerebellum 
have not been very clearly made out by physiologists. 
One of them seems to be to harmonize movements, 
that is, to cause the muscles to move in a steady and 
regular manner. It has been observed that when the 
cerebellum has been injured or diseased, walking or 
other movements of the limbs became unsteady and 
disorderly. The pons Yarolii serves chiefly to con- 
nect the medulla oblongata with the cerebellum and 
cerebrum. Some important nerves arise in large part 
in its substance. In the medulla oblongata arise the 
nerves which are most essential to life, those which 
go to the face, throat, neck, lungs, heart, and stomach. 
A wound or disease of a very small portion of the 
medulla oblongata will sometimes cause death. 
76. The Spinal Cord.—The spinal cord is con- 
nected with the medulla oblongata above, and extends 
downwards through the cavity or canal in the back- 
bone. It is from fifteen to eighteen inches long, and 
has cracks or fissures running its whole length and 
dividing it into different parts. 
77. The Nerves.—Nerves are given off from the 
brain and from the spinal cord in pairs. These are 
called the cerebrospinal nerves—those coming directly 
from the brain being the cranial nerves, because they 
come from within the cranium or skull, and those 
from the spinal cord being the spinal nerves. (Fig. 24.) FIRST LESSONS IN PHYSIOLOGY. 
Fig, 24—A Back View of the Brain and of the Spinal Cord and its Branches, THE NERVOUS SYSTEM. 
75 
78. The Cranial Nerves, or Nerves of the Brain. 
—Twelve pairs of nerves go off directly from tire base 
of the brain. Figure 25 is a picture of the base of 
Fig, 25.—The Base of the Brain. 
the brain. As here seen, the nerves have been cut off 
before going into the openings in the skull. After 
passing through these holes they send branches off in 
various directions, some to the nose, some to the eyes, 
some to the ears, some to the scalp, forehead, and 
cheeks, some to the mouth, tongue, throat, and neck, 
some to the windpipe, lungs, heart, and stomach, and 
other organs of the abdomen. 76 
FIRST LESSONS IN PHYSIOLOGY. 
79. The Spinal Nerves.—In the sides of the back- 
bone or spinal column are numerous little holes, 
through which nerves pass to all parts of the trunk 
and limbs. These spinal nerves are connected indi- 
rectly with the brain as well as with the spinal cord. 
This is important to know; otherwise, it may not be 
understood how the brain receives messages from and 
controls all parts of the body. The spinal nerves 
appear to end when they reach the spinal cord; but 
the truth is, that in the spinal cord are tracts or roads 
along which messages can go up from the spinal nerves 
to the brain, and come down from the brain to the 
spinal nerves. 
80. The In-coming and Out-going Nerves.—The 
nerves have been spoken of as if they all went out 
from the brain and spinal 
cord. More properly, some 
come in and some go out. 
In the spinal cord some 
nerve-fibres are running 
upwards, others down- 
wards. Both the out-going and in-coming nerves are 
in the same bundle up to a point near the spinal cord, 
where they divide. The middle part of Fig. 26 gives 
an idea of what would be seen if the spinal cord were 
cut across with a knife. In the central portion are two 
sets of horns. Between and outside of these are spaces, 
which look black in the picture but in reality are white, 
the horns being gray. The nerves, or their continua- 
tions, pass up and down the white parts or columns. 
The gray horns are centres of nerve force. 
Fig, 26—A Section of the Spinal Cord. THE NERVOUS SYSTEM. 
77 
81. Sensory and Motor Nerves.—The in-coming 
nerves, those which carry news from all parts of 
the body to the brain, are also called sensory nerves; 
through them the brain gets acquainted with what is 
going on in and around the body. They are the 
nerves which bring about the sensations of touch, 
pain, temperature, etc. The out-going nerves, those 
which carry impulses or messages from the brain to 
all parts of the body, are also called motor nerves, be- 
cause they chiefly go to muscles, and carry orders about 
movements. Each muscle or group of muscles has its 
own motor nerves. Certain parts of the brain are all 
the time in direct communication with certain muscles. 
Through some kind of an action in the brain, which 
we cannot fully comprehend, it is willed in the brain 
that a muscle shall move. Instantly the message goes 
to that muscle by way of the nerve tract in brain, 
spinal cord, and nerve, and the muscle obediently con- 
tracts. How the message is carried we cannot exactly 
say. Some think that it is simply by a sort of motion 
conveyed along the little molecules of the nerve tissue. 
It certainly is mysterious, and yet not much more so 
than the sending of messages along telegraph wires. 
82. Reflex Action of the Spinal Cord and Brain. 
—Every movement performed by muscles is not di- 
rected by the brain. Sometimes muscular actions 
occur without the will or mind seeming to have 
anything to do with them. If your foot is tickled 
while you are asleep, you may draw it up without 
awaking. Here the mind does not seem to act, at 
least not in the ordinary way. Such a movement 78 
FIRST LESSONS IN PHYSIOLOGY. 
is called a reflex action. The term reflex is de- 
rived from words meaning “to flow back again.” 
Impressions are taken up by the sensory nerves, the 
ends of which are in the skin, and are carried by these 
nerves to nerve-centres in the gray horns of the spinal 
cord. From these centres they are reflected or thrown 
back along a motor nerve or nerves to the muscles of 
the foot and leg, and movement is the result. The 
brain is asleep and off guard, and does not take any 
note of such actions. Some reflex actions, such as 
coughing, sneezing, winking, etc., are performed 
through the brain. Walking, standing, piano-play- 
ing, and similar actions are also sometimes accom- 
plished in a reflex manner, that is, without the inter- 
position of the will. 
83. The Sympathetic System of Nerves.—One 
set of nerves and ganglia found in the body is usually 
called the sympathetic system of nerves. One part of 
this system consists of a chain of gray ganglia, joined 
by a long cord, and situated on each side of the front 
of the spinal column in the neck, chest, abdomen, and 
pelvis. On or near the great organs, which are in the 
large cavities of the trunk, are networks of nerves and 
ganglia which belong to this system. Scattered here 
and there in little nooks and corners of the skull are also 
some of its ganglia. The different parts of the system 
are all connected, and are also united with the spinal 
cord or brain. 
84. Physiology of the Sympathetic System of 
Nerves.—Nerves which go to blood-vessels are called 
vaso-motor nerves. Yaso-motor nerves are found in SYLLABUS. 
79 
all parts of the nervous system. They come some- 
times directly from the brain and spinal cord, without 
getting mixed with the sympathetic system. Many 
of them, however, pass to the blood-vessels by way 
of the sympathetic ganglia. Blood-vessels have mus- 
cular tissue in their walls. The messages which 
travel along the vaso-motor nerves to the vessels cause 
them sometimes to contract or squeeze together, some- 
times to dilate or become wider. In this way the 
supply of blood to different parts of the body, and 
particularly to the internal organs, is largely regulated 
through the sympathetic system. 
Syllabus. 
Our arms, and legs, and eyes move in this way or in that, because 
we wish or will them so to move. Something within us directs and 
regulates these movements. 
All machinery must be guided and controlled. 
The machinery of the body is regulated by a part of the machine 
itself. A muscle moves because something tells it to move. 
The order to move comes from the brain, and journeys by way of 
the spinal cord and nerves to the muscle. 
The skull is filled with the brain, and the spinal canal with the 
spinal cord. 
Running off from the brain and spinal cord to every part of the 
body are cords, called the nerves. 
The brain, spinal cord, and nerves, with little gray masses of ner- 
vous matter called ganglia, which are found here and there all over 
the body, make up the nervous system. 
The nervous system is composed of gray matter and white matter. 
The outside of the brain is made up chiefly of gray matter, the in- 
terior of white; the external portions of the spinal cord are com- 
posed of white matter, the internal of gray. 80 
FIRST LESSONS IN PHYSIOLOGY. 
Isolated masses of gray matter are found in the brain, and ganglia 
are scattered throughout the body. 
Nerves are formed of white matter. 
The gray substance is the source of force or power; the white is 
made up of fibres or tracts, which convey impressions or messages. 
The cerebrum, or greater brain, comprises about six-sevenths of 
the entire brain. Its external surface is made up of convolutions 
and fissures. 
Underneath the cerebrum is the cerebellum, or lesser brain, the cut 
surface of which presents a beautiful tree-like appearance. 
The medulla oblongata, or oblong marrow, is about one inch long, 
and is situated where the brain and spinal cord come together. 
Between the medulla oblongata and the other portions of the brain 
is the pons Varolii, or bridge of Varolius. 
The outer membrane of the brain is called the dura mater, or 
“ hard mother.” The inner membrane is called the pia mater, or 
“ delicate mother.” 
Some anatomists speak of a third membrane, which is called the 
arachnoid, from Greek words meaning “ resembling a spider’s web.” 
It is composed of two layers, one on the inside of the dura mater 
and the other on the outside of the pia mater. 
Each division and sub-division of the brain probably has its own 
special function. 
The gray matter of the cerebrum is the chief organ of the mind. 
The mind is that something within us by means of which we be- 
come conscious of sensations, by which we can fix our attention, and 
by which we can remember, think, judge, reason, and govern. 
We know that the cerebrum is the chief organ of mind, because 
when it is injured, diseased, or imperfectly developed, the mind is 
more or less unsound. 
Different parts of the cerebrum are probably concerned with differ- 
ent functions of the mind. 
One of the functions of the cerebellum seems to be to harmonize 
movements. 
The pons Varolii serves chiefly to connect the medulla oblongata 
with the cerebellum and cerebrum. Some important nerves arise in 
its substance. 
In the medulla oblongata arise the nerves which are most essential 
to life. SYLLABUS. 
81 
The spinal cord is from fifteen to eighteen inches long, and has fis- 
sures running its whole length and dividing it into different parts. 
Nerves are given off from the brain and spinal cord in pairs, and 
are called the cerebro-spinal nerves. 
The nerves which come directly from the brain are called the cra- 
nial nerves, those from the spinal cord the spinal nerves. 
Twelve pairs of nerves go off directly from the base of the brain, 
passing through holes in the skull to the nose, eyes, ears, scalp, fore- 
head, cheeks, mouth, tongue, throat, neck, windpipe, lungs, heart, 
stomach, and other organs of the abdomen. 
Spinal nerves pass through little holes in the backbone to all parts 
of the trunk and limbs. 
In the spinal cord are tracts or roads, along which messages can go 
up from the spinal nerves to the brain, and come down from the 
brain to the spinal nerves. 
In the spinal cord some nerve-fibres are running upwards, others 
downwards. 
In the central portion of the spinal cord are two sets of gray horns. 
Between and outside of these horns are the tracts or columns of 
white matter. 
The gray horns of the spinal cord are centres of nerve force. 
The in-coming nerves, those which carry news from all parts of the 
body to the brain, are also called sensory nerves. They bring about 
the sensations of touch, pain, temperature, etc. 
The out-going nerves, those which carry impulses or messages from 
the brain to all parts of the body, are also called motor nerves, be- 
cause they chiefly go to muscles and carry orders about movements. 
Certain parts of the brain are in direct communication with cer- 
tain muscles. It is willed in the brain that a muscle shall move, and 
instantly the message goes to that muscle by way of the nervous sys- 
tem. 
It is thought that impulses or messages are conveyed by motion 
of the little molecules of the nerve tissue. 
Sometimes muscular actions occur without the will or mind seem- 
ing to have anything to do with them ; these are reflex actions. 
Impressions are taken up by the sensory nerves, the ends of which 
are in the skin, and are carried by these nerves to spinal centres. 
From these centres they are reflected or thrown back along a motor 
nerve or nerves to the muscles. 
SQme reflex actions, such as coughing, sneezing, winking, etc., are 82 
FIRST LESSONS IN PHYSIOLOGY. 
performed through the brain ; while walking, standing, piano-play- 
ing, and similar actions are also sometimes accomplished in a reflex 
manner. 
The sympathetic system of nerves consists of a chain of gray gan- 
glia, joined by a long cord, and situated on each side of the front of 
the spinal column in the neck, chest, abdomen, and pelvis. 
In the large cavities of the trunk, and within the skull, are nerves 
and ganglia which belong to this system. The different parts of the 
system are all connected, and are also united with the spinal cord or 
brain. 
Nerves which go to blood-vessels are called vaso-motor nerves, and 
are found in all parts of the nervous system. Many of them pass to 
the blood-vessels by way of the sympathetic system of nerves. 
Messages which travel along the vaso-motor nerves cause the ves- 
sels to contract or dilate, and thus help to regulate the supply of 
blood to different parts of the body. 
Questions for Review. 
What results from the contraction of muscles ? 
Why do our arms, legs, and eyes move in certain directions ? 
What directs and regulates these movements ? 
Why must machinery be guided and controlled ? 
How are ordinary machines managed ? 
By what is the machinery of the body regulated? 
Why does a muscle move ? 
Whence comes the order to move, and by what road does it travel 
Where is the brain situated ? 
Where is the spinal cord situated ? 
What are the nerves ? 
What parts make up the nervous system ? 
Of what two kinds of tissue is the nervous system composed? 
Where is the gray matter of the brain found ? 
Where is the white matter found ? 
Of what are the external portions of the spinal cord composed? 
Of what are the internal parts composed ? 
What isolated masses are found in the brain ? 
Where are ganglia found ? QUESTIONS FOR REVIEW. 
83 
Of what kind of tissue are the nerves formed ? 
What portion of the nervous system is the source of force’or power ? 
What portion conveys impressions or messages ? 
What is the greater brain called ? 
How much of the entire brain does it comprise ? 
To what shape does it conform ? 
What are seen upon its external surface? 
What is situated underneath the cerebrum ? 
What is the length of the medulla oblongata? 
How do some regard the medulla oblongata ? 
What is the meaning of pons Varolii? 
How many coats or membranes has the brain ? 
What is the outer membrane called? 
Why were the terms “ dura ” and “ mater” applied to it? 
What is the inner membrane called ? 
What is the characteristic of this membrane ? 
What third membrane is sometimes spoken of by anatomists ? 
What is the derivation of the word arachnoid ? 
Of what layers is it composed ? 
Of what may these so-called layers of the arachnoid be considered 
as parts ? 
What is the chief organ of the mind ? 
What is the mind? 
How do we know that the cerebrum is the chief organ of the mind ? 
With what are different parts of the cerebrum concerned? 
Of what sensations do we become aware in one portion ? 
What faculties are seated in another part ? 
What centres are located in still another region ? 
What seems to be one of the functions of the cerebellum ? 
What has been observed when the cerebellum has been injured or 
diseased? 
What purpose does the pons Varolii serve? 
What arise in its substance? 
What nerves arise in the medulla oblongata ? 
What would be the effect of a wound or disease of a very small 
portion of the medulla oblongata ? 
How long is the spinal cord ? 
How is the spinal cord divided ? 
How are nerves given off from the brain and spinal cord? 
What is meant by the cerebro-spinal nerves ? 84 
FIRST LESSONS IN PHYSIOLOGY. 
Which are the cranial nerves? 
Which are the spinal nerves ? 
How many pairs of nerves go off from the brain ? 
To what do the cranial nerves send branches? 
Through what do the spinal nerves pass ? 
With what are the spinal nerves indirectly connected? 
What tracts or roads are found in the spinal cord ? 
Do all the nerves go out from the brain and spinal cord ? 
In what direction do the nerve-fibres in the spinal cord run ? 
Up to what point are the out-going and in-coming nerves together ? 
What is situated in the central portion of the spinal cord ? 
Where are the white columns of the cord situated ? 
What is the function of the gray horns ? 
By what name are the in-coming nerves known ? 
Why are they so called ? 
What is brought about by them ? 
What are the functions of the out-going nerves? 
What are they sometimes called, and why ? 
With what is each muscle or group of muscles supplied? 
With what are certain parts of the brain in direct communication ? 
Explain the process by which the brain causes the muscle to con- 
tract. 
How are messages probably conveyed along the nerve tracts ? 
Are all movements performed by muscles directed by the brain ? 
Give illustrations of movements occurring without the control of 
the will or mind. 
What is a movement which occurs independently of the will or 
mind called ? 
Give the derivation of the term reflex. 
Explain the process by which reflex actions take place. 
Mention some reflex actions performed through the brain. 
What set of nerves and ganglia is found in the body ? 
Of what does one part of the sympathetic system of nerves consist ? 
Describe the other portions of the sympathetic system. 
With what is the sympathetic system connected? 
What are vaso-motor nerves, and where are they found? 
How do many of these nerves pass to the blood-vessels ? 
What sort of tissue is found in the walls of blood-vessels? 
How is the supply of blood to different parts of the body largely 
regulated ? CHAPTER VIII. 
SENSATION AND THE SPECIAL SENSES 
85. Sensation.—An impression made npon any 
part of the body to such an extent that the mind rec- 
ognizes that something has been done, is a sensation. 
Through the nervous system impressions are received 
and given out, and we are put in communication with 
other beings and objects. If, for instance, we are struck, 
tickled, pinched, rubbed, cut, or burned, we have sen- 
sations of sticking, tickling, pinching, etc.; if we see a 
tree we have a sensation of sight; if we hear a voice or 
music we have a sensation of sound. For all sensations 
the individual must have (1) an apparatus to receive 
impressions, that is, sense-organs in the skin, eye, ear, 
etc.; (2) an apparatus to carry impressions to the brain, 
the in-coming or sensory nerves spoken of in the last 
chapter; and (3) an apparatus in the brain to convert 
the impressions into what becomes sensation to the 
mind. When the skin is touched, when light strikes 
the eye, or a sound the ear, when the tongue comes 
in contact with anything sweet, or the nose is greeted 
with an odor, sense-organs receive the impressions, and 
sensory nerve-tracts carry them to the brain, where 
we become conscious of a sensation. 86 
FIRST LESSONS IN PHYSIOLOGY. 
86. The Five Special Senses.—The five special 
senses are feeling, seeing, hearing, tasting, and smell- 
ing. These are the five ways or channels by which 
the mind becomes acquainted with the outside world. 
Sometimes all or several of the senses act; sometimes 
only one is brought into service. We hear an apple 
fall, we look in the direction of the sound and see it, 
we touch it, picking it up, we smell its fragrance, and 
finally we taste it. Each and all of the senses have 
given some information about the apple. The blind 
man uses touch alone when he feels a piece of cloth 
to determine what it is. 
87. Feeling or Touch.—The skin is the great 
organ of the sense of touch. Immense numbers of 
nerve filaments are found in the true skin. The ends 
of these take up impressions which arise from contact 
of the skin with any object. These impressions finally 
get into the brain as sensations of touch. By this 
sense of touch we learn whether bodies are hot or 
cold, rough or smooth, wet or dry. In some parts of 
the body, in the fingers and hands, for instance, the 
sense of touch is very delicate. If the skin is burned, 
pain is caused. The reason of this is that the nerves, 
which usually are only slightly excited by touch, are 
greatly excited by contact causing pain. When the 
skin comes in contact with a hot or cold body a pecu- 
liar sensation is caused, which some think is entirely 
distinct from touch. When a weight is raised, the 
sensation seems also to be not altogether one of touch. 
88. The Media or Clear Parts of the Eye.—The 
organ of sight is the eye. Cutting through the mid- SENSATION AND THE SPECIAL SENSES. 
87 
die of the eyeball from above downwards, and from 
before backwards, we get the appearance seen in Fig. 
27. Going from before backwards, we first see the 
Fig. 27. —Section of the Eyeball. 
clear part of the eye, or cornea, what is sometimes 
called, but wrongly, the “ sight of the eye.” The word 
cornea comes from cornu, “ a horn,” and this part of 
the eye is so called because it bears some resemblance 
to very thin horn. Next comes a little room or cavity, 
the front or anterior chamber, which contains a fluid 
known as the aqueous or watery humor. Hanging in 
this chamber is a circular curtain, the ms, which has 
a hole in it called the pupil. The word iris means 
“ rainbow ; ” it is this curtain which gives the eye its 
peculiar color. The iris contains muscular fibres, 
which contract and expand, and so alter the size of 
the pupil. In bright light the pupil is small, in the 
dark it is large; and thus the amount of light ad- 
mitted to the eye is regulated. Just behind the iris 
you come to a hard body, the crystalline lens, which is 88 
FIRST LESSONS IN PHYSIOLOGY. 
perfectly clear, and has two sides curved outwards. 
Back of this lens is the posterior chamber of the eye, 
which is filled with a jelly-like mass, called the vit- 
reous or glassy humor. The cornea, aqueous humor, 
pupil, crystalline lens, and vitreous humor are the 
media of the eye, placed between the outside light and 
the nerve of sight. 
89. The Coats or Coverings of the Eye.—Be- 
sides the cornea in the front of the eye, this organ has 
three distinct coats or coverings. The outer protect- 
ing one is the sclerotic or hard coat; it forms, so far 
as it is visible, the “ white of the eye.” To this the 
muscles of the eyeball are attached. The middle coat 
is called the choroid, a word which means “ like the 
skin; ” it is like the true skin in that it contains a 
great number of blood-vessels. It is a very dark 
membrane, containing many pigment or paint cells. 
The object of these dark cells is to absorb some of 
the rays of light. If all the rays of light which 
strike the eyeball were allowed to enter the eye, and 
affect the nerve of sight, vision would be dazzled and 
confused. The third, inner coat of the eye is the 
retina. The word rete means a “net,” and the retina 
has been compared to a network spread out over the 
inner surface of the eye. It is the sensitive, nervous 
coat of the eye. 
90. The Nerve of Sight.—On page 75 is a picture 
of the base of the brain, to which attention was called 
in the last chapter. Near the front of this picture 
two tracts of nerve tissue can be seen crossing each 
other, somewhat like the letter X. These are the SENSATION AND TEE SPECIAL SENSES. 
89 
optic nerves, or nerves of sight, forming at this point 
what is called the optic chiasm or commissure. Chiasm 
comes from a Greek verb, which means “ to make the 
letter X;” and commissure signifies “a joining to- 
gether;” and hence it can be seen why these names 
are given. Back of the place of crossing one of these 
nerve tracts goes to one side of the brain, while the 
other passes to the opposite side; in front of the 
chiasm one nerve proceeds through an opening in one 
of the bones of the head to the right eye, the other 
goes to the left. The nerve passes through the two 
outer coats of the eye, and becomes continuous with 
the inner coat or retina. 
91. The Bending of Light in the Eye.—When 
light passes from one clear substance to another of 
different density, it is bent from the straight course 
which it has been taking. These clear substances will 
cause more or less bending of the rays of light accord- 
ing to their shape. A curved surface will cause a 
very considerable bending. A piece of glass with a 
double curve, like that of the crystalline lens, has a 
very decided refracting power. It will bend rays of 
light to a point. When rays of light come to the eye 
they strike first upon the curved cornea, which bends 
them a little from their course. After awhile they 
reach the crystalline lens, which bends them very de- 
cidedly ; so much so as to actually cause the rays to 
fall upon the retina in such a way as to produce an 
image upside down. 
92. Pictures upon the Retina.—When the pho- 
tographer takes a picture he places his subject before 90 
FIRST LESSONS IN PHYSIOLOGY. 
a box, with a hole in the front part of it. This is 
what is called the camera obscura, or dark chamber; 
it is coated or painted inside with some dark sub- 
stance. At the end next to the person who is being 
photographed is an opening, containing a lens. At 
the other end is a piece of glass coated with a chemical 
substance, on which light acts very quickly. The 
rays of light coming from the subject strike the lens, 
and are bent by it in such a way that they fall right 
upon the chemical substance, and form there a picture. 
The eye may be compared to a camera obscura. The 
retina has, during life, a red color, due to a peculiar 
coloring matter, which is called retinal red. It is 
probably a chemical substance of extreme delicacy 
and sensitiveness, on which light waves from different 
objects, or objects of different colors, so act as to give 
rise to different changes in it. According to the kind 
of change effected will be the impression made on the 
nerve-ends, and conveyed back to the brain. 
93. The Process of Seeing.—Rays of light pass 
through the beautifully clear media of the eye and 
through the pupil; they are bent by the crystalline 
lens so that they fall directly upon the retina. They 
cause a picture of the object from which they come 
to be made upon the retina. They produce a stir in 
the retina. They probably set up in it some kind of 
minute motion. We commonly say that light makes 
an impression on the retina. This stir, or motion, or 
impression, travels from the retina back along the optic 
nerves to the brain ; and in the brain, in some way not 
fully understood, it becomes the sensation of sight, and 
the object is seen right side upwards. SENSATION AND THE SPECIAL SENSES. 
91 
94. The Organ of Hearing.—Only second to sight 
in importance is the sense of hearing. The organ of 
hearing is the ear, of which you have a view (Fig. 28). 
It consists of three parts, the external ear, the middle 
ear, and the internal ear. The external ear includes 
the projecting and curiously curved part commonly 
called the ear and the little tube or canal, the external 
auditory canal, which can be seen extending inwards 
from the outside. This canal is about one inch long. 
At its inner end it is closed by a membrane called the 
membrane of the tympanum. The middle ear is a little 
cavity just inside of this membrane. This cavity is 
called the tympanum or drum. A canal or tube about 
one and a half inches long runs from this middle ear or 
tympanum to the throat. It is called the Eustachian 
tube, after an anatomist, Eustachius, who first described 
it. Both the Eustachian tube and middle ear are lined 
with delicate mucous membrane. The internal ear is 
Fig. 28—View of the Ear. 92 
FIRST LESSONS IN PHYSIOLOGY. 
also called the labyrinth, because of its complex char- 
acter. This internal ear or labyrinth is made up of 
curiously shaped canals and cavities in the bones. 
95. The Nerve of Hearing.—The auditory nerve, or 
nerve of hearing, is one of the nerves given off directly 
from the brain. It proceeds from the base of the brain 
by bony passages to the internal ear, in the cavities 
and canals of which it is distributed, ending in minute 
plates and hair-like filaments. This nervous portion 
of the organ of hearing is bathed all the time in a 
fluid which is within the labyrinth. 
96. The Process of Hearing.—A sound like that 
of a voice, a bell, or a cannon sets the air around into 
vibration. This vibration is carried as a wave of sound 
to the external ear. It passes into the external audi- 
tory canal, and strikes against the membrane of the 
tympanum, which is also made to vibrate. These vi- 
brations are communicated to little bones within the 
ear, by which they are carried along to the labyrinth 
or internal ear. The liquid in the labyrinth, and 
finally the little nerve ends, take up the motion, which 
is conveyed along the trunk of the auditory nerve to 
the brain and becomes there the sensation of hearing. 
This is the usual process. Sound, however, instead 
of coming through the external canal of the ear, may 
reach the labyrinth by the bones of the head. If a 
watch is placed against the forehead, or against the 
teeth, its ticking can be heard very distinctly, the 
sound being carried by way of the bones of the head 
to the internal ear. SENSATION AND THE SPECIAL SENSES. 
97. Taste.—If salt, sugar, vinegar, or a bitter med- 
icine is placed on the tongue, it produces a peculiar 
sensation—it is tasted, for the tongue is the organ of 
taste. The tongue is supplied by two nerves, branches 
from one going to the front, and from the other to the 
back part of the organ. Impressions are carried by 
one or both of these nerves to the brain. The mucous 
membrane which covers the tongue is raised into little 
points or papillae, and to these go little nerve filaments 
and blood-vessels. Through these points impressions 
of taste and other impressions also are received. 
98. Smell.—The sense of smell is brought about 
by an arrangement very similar to that for the other 
senses. The nose, as has already been learned, is lined 
with mucous membrane. At the front part of the 
base of the brain are the nerves of smell, or olfactory 
nerves, one on each side. They are of large size 
and club-shaped (Fig. 25). From these nerves of 
smell a large number of little nerve branches go down 
through minute holes in the floor of the skull to the 
mucous membrane which lines the nostrils and the 
cavities connected with them. This membrane, like 
the tongue, has scattered all over it little papillae or 
projections, in which the delicate nerve-branches end, 
or, perhaps, more properly, begin. Odors carried by 
the air enter the nose, act upon the nerve-ends, and 
the impressions made are hurried back to the great 
nerves of smell in the brain, and the sensation of smell 
results. 94 
FIRST LESSONS IN PHYSIOLOGY. 
Syllabus. 
Impressions are received and given out through the nervous system. 
A sensation is any impression made upon any part of the body to 
such an extent that the mind recognizes that something has been done. 
Sensations require (1) an apparatus to receive impressions; (2) an 
apparatus to carry impressions to the brain; (3) an apparatus in the 
brain to convert the impressions into what become sensations to the 
mind. Sense-organs in the skin, eye, ear, etc., receive the impressions, 
and sensory nerves carry them to the brain. 
The five special senses are feeling, seeing, hearing, tasting, and 
smelling. Sometimes all or several of the senses act; sometimes only 
one is brought into service. 
The skin is the great organ of the sense of touch. 
Nerve-ends in the true skin take up impressions of contact. These 
impressions finally get into the brain as sensations of touch. 
If the skin is acted upon by cutting, burning, etc., pain is caused. 
The nerves which are only slightly excited by touch are greatly 
excited by contact causing pain. 
The organ of sight is the eye. 
The media of the eye are the cornea, the watery humor in the front 
chamber of the eye, the pupil, the crystalline lens, and the glassy 
humor in the posterior chamber. 
The iris is a circular curtain hanging in the watery humor. The 
pupil is a hole in this curtain. The iris gives the eye its color. It 
contains muscular fibres, which by contracting and expanding alter 
the size of the pupil. 
The eye has three coats—(1) the outer sclerotic or hard protecting 
coat; (2) the middle or choroid coat, containing many dark pigment 
cells, which prevent too much light from entering the eye; (3) the inner 
coat or retina, which is the sensitive or nervous portion of the eye. 
The optic nerves, or nerves of sight, which go to the retina cross 
at the base of the brain, one nerve-tract going to one side of the brain, 
while the other passes to the opposite side. 
When rays of light come to the eye they strike first upon the curved 
cornea, which bends them a little from their course. The crystalline 
lens bends them still more, so as to actually cause them to fall upon 
the retina in such a way as to produce an image upside down. 
The eye can be compared to the photographer’s camera obscura, or 
dark chamber, SYLLABUS. 
95 
The retina has during life a red color, due to a peculiar coloring 
matter, which is called retinal red. 
Retinal red is probably a chemical substance of extreme delicacy 
and sensitiveness, on which light waves from different objects so act 
as to give rise to different impressions. 
Rays of light cause a picture of the object from which they come 
to be made upon the retina. They make an impression on the retina, 
which travels back along the optic nerves to the brain. 
The organ of hearing is the ear, which consists of three parts—the 
external, middle, and internal ear. 
The external ear includes the part commonly called the ear, and 
the little canal which can be seen extending from the outside inwards. 
The inner end of this canal is closed by a membrane called the mem- 
brane of the tympanum. 
The middle ear is a little cavity called the tympanum or drum. 
The Eustachian tube runs from it to the throat. 
The internal ear is called the labyrinth, because of its complex 
character. It is made up of curious canals and cavities in the bones. 
The auditory nerve, or nerve of hearing, proceeds from the base 
of the brain by bony passages to the internal ear. 
A sound sets the air into vibration. This wave of sound passes 
into the external ear canal and causes the membrane of the tympanum 
to vibrate. 
The vibrations of the membrane of the tympanum are communi- 
cated to little bones within the ear, by which they are carried along 
to the labyrinth or internal ear. The liquid in the labyrinth, and 
finally the auditory nerve, take up the motion, which is conveyed to 
the brain and becomes there the sensation of hearing. 
Sound sometimes reaches the labyrinth by the bones of the head. 
The tongue is the organ of taste. 
In the tongue are branches from two nerves, those from one to the 
front, those from the other to the back part of the organ. 
The mucous membrane which covers the tongue is raised into little 
points or papillae, and to these go little nerve filaments and blood- 
vessels. Through these points impressions of taste, and other impres- 
sions also, are received. 
From the nerves of smell at the base of the brain branches go down 
through holes in the skull to the mucous membrane of the nostrils. 
Pdors act upon the jaerve-ends in the mucous membrane. 96 
FIRST LESSONS IN PHYSIOLOGY. 
Questions for Review. 
What are the functions of the nervous system ? 
What is a sensation ? Give illustrations. 
What three things are necessary in order that sensations may be 
produced ? 
Give illustrations of the forms of apparatus for sensations. 
What are the five special senses ? 
What are the functions of these senses ? 
How many Of the senses may act at one time ? 
Give an illustration of the action of all the senses. 
Give an illustration of the use of only one sense. 
What is the organ of the sense of touch ? 
What are found in the true skin ? 
How are sensations of touch brought about through the nerves of 
the skin ? 
Of what do we learn by the sense of touch? 
Where is the sense of touch very delicate ? 
Explain the difference between the sensation of touch and that of 
pain. 
What results when the skin is touched by a hot or cold body ? 
What results when a weight is raised ? 
What is the organ of sight ? 
What is the cornea ? Why is it so called ? 
What is the name of the little room or cavity in the front of the eye ? 
What fluid does the anterior chamber of the eye contain? 
What curtain hangs in this chamber ? 
What is the pupil of the eye ? 
What is the meaning of the word “ iris”? 
What does the iris give to the eye ? What does the iris contain ? 
How is the admission of light to the eye regulated ? 
Where is the crystalline lens ? Describe it. 
Where is the posterior chamber of the eye ? What does it contain ? 
What are the media of the eye ? 
How many coats or coverings has the eye ? 
What is the outer coat of the eye called ? 
What does this coat form and what are attached to it ? 
What is the middle coat of the eye called ? Why ? 
What does the choroid coat contain ? 
What is the object of the dark cells of the choroid, i QUESTIONS FOR REVIEW. 
97 
What is the inner coat of the eye called ? Why ? 
What is the function of the retina ? 
Where do the optic nerves cross ? 
What is the meaning of the words chiasm and commissure ? 
What is the course of the optic nerve tracts behind the chiasm ? 
With what coat of the eye is the optic nerve continuous? 
What happens to a ray of light when it passes from one clear sub- 
stance to another ? 
What is the effect of a curved surface ? What of a double curve 
like that of the crystalline lens ? 
Describe the course of rays of light after reaching the eye. 
Describe a camera obscura. 
To what is the red color of the retina during life due ? 
What is the probable nature of retinal red? How does it act? 
Describe the process of seeing. 
What is the organ of hearing ? 
Of what three parts does the ear consist? 
What does the external ear include ? 
What is the membrane of the tympanum ? 
What is the middle ear ? What is its cavity called ? 
What tube runs from the middle ear to the throat ? 
With what are the Eustachian tube and middle ear lined ? 
What is the internal ear also called ? Why ? 
Of what is the internal ear or labyrinth composed ? 
What is the name of the nerve of hearing ? 
Where does the nerve of hearing originate? Describe its course. 
In what is the nervous portion of the organ of hearing bathed ? 
Describe the usual process of hearing. 
Instead of coming through the external auditory canal, in what 
other way may sound reach the internal ear? Give an illustration. 
What is the organ of taste ? 
What nerve branches are found in the tongue ? 
What are their functions ? 
What are the papillae of the tongue? 
How is the sense of smell brought about ? 
With what is the nose lined ? 
Where are the nerves of smell situated and what are they called ? 
Describe the course of the branches of the nerves of smell. 
Describe the process of smelling. CHAPTER IX. 
CARE OF THE NERVOUS SYSTEM AND 
SENSE ORGANS. 
99. Importance of Caring for the Nervous Sys- 
tem.—The importance of carefully guarding the 
nervous system is very evident. The brain, being the 
governing part of the body, must be kept in good 
health, or the machinery of the system, which it di- 
rects, will be allowed to jangle and get out of tune. 
The spinal cord, along which some of the messages to 
and from the brain centres are carried, and which 
contains centres of its own, must also be sound, or 
the performance of its functions will not be properly 
effected. The sensory nerves must not be broken or 
injured, or impressions will not be conveyed smoothly 
upwards to the spinal cord and brain. The motor 
nerves must be intact in order to receive and convey 
the messages from the brain as they are sent. 
100. Exercise of the Brain.—As the brain is the 
chief organ of the mind, its regular exercise will 
improve the mental powers. Much can be done in 
childhood towards establishing good habits of mind. 
Careful training of the senses will help in this direc- CARE OF THE NERVOUS SYSTEM. 
99 
tion, as our knowledge really comes from sensations. 
Even the higher faculties of the mind, such as atten- 
tion, will, memory, and judgment, are improved by 
exercise of the brain. Children sometimes seem to 
look without seeing, and to listen without hearing; 
they should learn to observe closely and attend to 
what they observe. In reading, they should try to 
understand clearly every word and thought. Study 
will improve the mind, and will not injure the body, 
if proper care is taken to preserve the health by regu- 
lar habits of eating, sleeping, exercise, and recreation. 
Mental labor must not be carried to excess. 
101. Causes of Disease of the Brain and Nervous 
System.—Alcoholic drinks, such as whiskey, brandy, 
gin, wine, beer, ale, etc., are often the cause of serious 
diseases of the nervous system. When large quanti- 
ties of alcohol are taken in a short time, drunkenness 
is produced, chiefly through its effects upon the brain. 
If its use is continued, the faculties of the mind be- 
come impaired. Sometimes the tissues and vessels of 
the brain become so altered that they cannot properly 
perform their functions. We should learn from this 
that, while alcohol may have its uses, it should not be 
abused. Continued care, anxiety, or excitement will 
also have a tendency to weaken and depress the brain. 
Prolonged exposure to the sun, or to excessive heat, 
with fatigue, is also a cause of disease of this organ. 
102. Paralysis.—A condition known as paralysis, 
or palsy, is sometimes the result of disease or injury 
of some part of the nervous system. The term pa- 
ralysis comes from a Greek word meaning to “loosen” 100 
FIRST LESSONS IN PHYSIOLOGY. 
or “disable.” It is an affection characterized by a 
loss or diminution of power. The arm that is com- 
pletely paralyzed cannot.be lifted from the side; the 
palsied leg will drag like a dead weight. The mus- 
cles no longer act as they do in health. The disease 
or injury which causes the paralysis may be situated 
in the brain, in the spinal cord, or in the nerves. A 
vessel may break in the brain, causing a blood-clot to 
form, and this clot destroys the centres which govern 
and direct muscular movements. The spinal cord 
may be crushed, or may be diseased, so that messages 
cannot travel up and down it, or so that its centres 
cannot act, and spinal paralysis results. Disease or 
injury of a nerve causes paralysis by cutting off com- 
munication between the muscles and the brain or 
spinal cord. When the serious nature of paralysis 
is considered, the importance of carefully guarding 
the nervous system from harm and overstrain will 
be recognized. 
103. Sleep.—Sleep has well been called “tired na- 
ture’s sweet restorer.” Without sleep the brain would 
soon wear out. The work and turmoil of the day- 
keep the brain in a state of constant activity. Wear 
and waste always go hand in hand with activity; hence, 
the brain becomes exhausted. Sleep helps to renew 
and rebuild. During sleep the voluntary muscles are 
at rest, and breathing, circulation, and temperature 
are diminished. About eight hours out of the twenty- 
four is the proper allowance of sleep for most adults. 
Children, and those who are weakly or hard-worked, 
will generally require more than eight hours. CARE OF THE NERVOUS SYSTEM. 
101 
101. Defects of Sight.—Two of the most common 
defects of vision are short-sight and long-sight, which 
are generally due to a faulty shape of the eyeball. 
In short-sight, or near-sightedness, the globe of the 
eye is too long, and rays of light are bent to a focus 
in front of the retina. Objects can then only be 
seen clearly when they are close to the eye. Concave 
glasses are employed to correct this defect. In long- 
sight, or far-sightedness, the globe of the eye is too 
short, and hence rays of light from an object at an 
ordinary distance come to a focus behind the retina. 
Convex glasses must be used. Sometimes, instead of 
the eyeball being simply too long or too short, it is 
irregular in shape. Glasses made with special curva- 
tures in different directions are then necessary. The 
eye can be adjusted to see near or distant objects by 
what is called the function of accommodation, which 
is performed by the crystalline lens, the curvature of 
this body increasing or diminishing. As age advances, 
however, the lens becomes less elastic and its curva- 
ture cannot well be increased, so that convex glasses 
are also required for this condition. 
105. How to Preserve Good Sight.—The sight 
often becomes poor because the eyes are sadly abused, 
especially in childhood and youth. Near-sightedness, 
in particular, which is said to be rapidly increasing in 
all civilized countries, is frequently acquired during 
school-life. At home and at school every precaution 
should be taken to counteract the injurious effects of 
protracted use of the eyes at a near point, as, in 
reading, writing, drawing, sewing, and similar work. 102 
FIRST LESSONS IN PHYSIOLOGY. 
Study-rooms should be well lighted. The light should 
be abundant, steady, and not glaring, and should en- 
ter from the left side! Desks should be inclined, so 
as not to compel the pupil to bend over too much 
when at work. School-books should be printed in 
large, clear type, and the pages should not be too 
broad. Whenever defective vision is suspected, the 
eye should at once be examined. If the condition of 
the sight was determined before entering school, much 
misery in after life would often be saved. 
106. Color-Blindness.—A peculiar defect of sight 
is called color-blindness. Usually, those who are color- 
blind are not able to distinguish between certain 
colors. The most frequent form of color-blindness is 
that for red; that for green comes next in frequency; 
rarely that for blue will be found. The term “ Dal- 
tonism” is applied to color-blindness, after Dalton, a 
famous English chemist, who was red-blind, and was 
the first to call scientific attention to the subject, de- 
scribing his own case in 1794. Children should be 
taught early to attend to colors. The color-sense can 
be improved by training, and sometimes the defect is 
apparent rather than real. 
107. Care of the Ears.—The ears, like the eyes, 
should be watched and guarded. They are often in- 
jured by introducing too much cold water, and by bor- 
ing and working at them. The ears can be cleaned 
with a soft, dry towel, or with a little warm water. The 
introduction of solid instruments, such as pins, probes, 
and ear-spoons, may injure the auditory canal, or even 
the drum of the ear. The ear may be injured even CARE OF THE NERVOUS SYSTEM. 
103 
by probing it roughly with the finger. If a foreign 
body gets into the ear, it can usually best be removed 
by gentle, steady syringing with warm water. When- 
ever the hearing is affected, when noises are heard in 
the ears, or when a discharge from this organ is no- 
ticed, a physician should be called. 
108. Cultivation of the Senses.—All of the senses 
can be improved by cultivation. Great delicacy of 
touch can be acquired by practice, as is seen in musi- 
cians, sculptors, mechanics, and sometimes to a re- 
markable extent among the blind. A girl, named 
Laura Bridgman, through severe sickness occurring 
in her infancy, lost sight, hearing, taste, and smell; 
but she was taught to write, and to read and talk 
with her fingers, learning more with her one sense 
of touch than some do with all their senses. The eye 
can be trained to see farther and better. The hearing 
can be improved by listening carefully, and trying to 
distinguish different sounds. The Indian, who de- 
pends so largely on his senses, usually has acute sight 
and hearing. Persons with “musical ears” can tell 
the slightest differences in notes. Even taste and 
smell can be improved by cultivation. If the senses 
are the inlets or channels by which knowledge enters 
the mind, those who cultivate most thoroughly each 
and all of them will, in the end, have acquired the 
most knowledge. 104 
FIRST LESSONS IN PHYSIOLOGY. 
Syllabus. 
The nervous system should be carefully guarded. 
Regular exercise of the brain will improve the mental powers. 
The senses should be carefully trained. 
Children should learn to observe closely and attend to what they 
observe. In reading, they should try to understand clearly every 
word and thought. 
Mental labor must not be carried to excess. 
Alcoholic drinks are often the cause of serious diseases of the ner- 
vous system. Continued care, anxiety, or excitement, and exposure 
to the sun, or to excessive heat, with fatigue, are also causes of ner- 
vous diseases. 
Paralysis sometimes comes on as the result of disease or injury to 
the nervous system. It is an affection characterized by loss or dimi- 
nution of power. 
The disease or injury which causes the paralysis may be situated 
in the brain, in the spinal cord, or in the nerves. , 
Without sleep the brain would soon wear out. Sleep helps to re- 
new and rebuild the brain worn and wasted by active work. 
During sleep the voluntary muscles are at rest, and breathing, cir- 
culation, and temperature are diminished. 
About eight hours out of the twenty-four is the proper allowance 
of sleep for most adults; but children, and the weakly or hard-worked, 
will sometimes require more. 
In short-sight the globe of the eye is too long, and rays of light 
are bent to a focus in front of the retina. Concave glasses are em- 
ployed to correct this defect. 
In long-sight the globe of the eye is too short, and rays of light 
come to a focus behind the retina. Convex glasses must be used. 
Sometimes the eyeball is irregular in shape, and glasses made with 
special curvatures are necessary. 
The eye can be accommodated for near or distant objects by the 
curvature of the crystalline lens increasing or diminishing. As age 
advances the lens becomes less elastic and its curvature cannot well 
be increased, so that now convex glasses are also required for this 
condition. 
The sight often becomes poor because the eyes are abused in child- 
hood and youth. Near-sightedness is often acquired during school-life. QUESTIONS FOR REVIEW. 
105 
Study-rooms should be well lighted. The light should enter from 
the left side. 
Desks should be inclined, so as not to compel the pupil to bend 
over too much when at work. School-books should be printed in 
large, clear type, and the pages should not be too broad. 
Whenever defective vision is suspected, the eye should at once be 
examined. Before entering school, the condition of sight should be 
determined. 
The most frequent form of color-blindness, or “ Daltonism,” is for 
red ; that for green comes next; rarely that for blue will be found. 
Children should be taught early to attend to colors. The color- 
sense can be improved by training, and sometimes the defect is ap- 
parent rather than real. 
The ears should be watched and guarded. They are often injured 
through ignorance and carelessness. 
The ears are injured by introducing too much cold water into them 
and hy boring and working at them too much. 
The ears can be cleaned with a soft, dry towel, or with a little warm 
water. If a foreign body gets into the ear it can usually best be re- 
moved by gentle, steady syringing with warm water. 
Whenever the hearing is affected, when noises are heard in the ear, 
or when a discharge from this organ is noticed, a physician should be 
called. 
All of the senses can be improved by cultivation ; and if the senses 
are the inlets or channels by which knowledge enters the mind, those 
who cultivate them most thoroughly will, in the end, have acquired 
the most knowledge. 
Questions for Review. 
Why should the brain be kept in good health ? 
Why should the spinal cord be sound ? 
Why must the sensory nerves not be broken or injured ? 
Why must the motor nerves be intact ? 
What will be the effect of regular exercise of the brain on the 
mental powers ? 
When can much be done towards establishing good habits of mind ? 
What is said of careful training of the senses ? 
What is said of the higher faculties of the mind ? 106 
FIRST LESSONS IN PHYSIOLOGY. 
How should children learn to observe ? 
How should they read ? 
What effect will study have upon the mind and body ? 
What diseases are often caused by alcoholic drinks ? 
How is drunkenness produced ? 
What effect has alcohol on the tissues and vessels of the brain ? 
Name some other causes of diseases of the nervous system. 
From what is the term paralysis derived? 
By what is it characterized ? 
Give some illustrations of forms of paralysis. 
Where may the disease or injury which causes the paralysis be 
situated ? 
Give an example of the manner in which paralysis may be caused 
by brain disease. 
How is spinal paralysis produced ? 
How does disease or injury of a nerve cause paralysis ? 
What does the serious nature of paralysis teach ? 
What has sleep been called ? 
What would be the effect of going without sleep ? 
What organs are at rest and what functions are diminished during 
sleep ? 
What is the proper amount of sleep for most adults ? 
How much sleep do children and the weakly or hard-worked re- 
quire? 
What are two of the most common defects of vision ? 
To what are they frequently due ? 
What is the condition in short-sight ? 
What kind of glasses is employed to correct short-sight ? 
What is the condition in long-sight ? 
What kind of glasses are used to correct this defect ? 
What other defect of the eyeball besides its being too long or too 
short is sometimes found ? 
How is this defect corrected ? 
How is the crystalline lens adjusted to see near or distant objects ? 
What effects has age on the function of accommodation ? 
What kind of glasses is required to correct the defect of sight 
which results from advancing years ? 
How does sight often become defective ? 
When is near-sightedness frequently acquired ? 
What precaution should be taken with reference to the eyes ? QUESTIONS FOR REVIEW. 
107 
How should study-rooms he lighted ? 
How should desks he inclined ? Why ? 
How should school-books be printed ? 
What should be done when defective vision is suspected ? 
What should be done before entering school ? 
What is color-blindness ? 
What is the most frequent form of color-blindness ? 
What is the origin of the term “ Daltonism”? 
What is said about teaching children to attend to colors ? 
How are the ears often injured ? 
How can the ears he cleaned ? 
Should solid instruments be introduced into the ear ? 
What course should be taken when any serious affection of the ear 
is present? 
Can the senses be improved by cultivation ? Give illustrations. 
Who in the end will have acquired the most knowledge ? CHAPTER X. 
THE BLOOD. 
109. What Blood Is.—The blood of living man 
is a red, warm fluid. It has been well called the vital 
or life-giving fluid. Good blood in proper quantity 
usually means good health. It is found almost every- 
where in the body; only a few tissues, such as the 
nails and hair, will not bleed when stuck or cut. 
Blood cannot be seen coursing along in the human 
body, even in rosy cheeks, where much of it is near 
the surface. In order to study it in a living animal, 
however, physiologists sometimes look at the web of 
a frog’s foot, which is very thin and contains many 
blood-vessels. 
110. Quantity of Blood in the Living Body.—The 
quantity of blood in the human body is about one- 
thirteenth or one-fourteenth of the weight of the body. 
If a man weighs one hundred and fifty-six pounds, 
about twelve pounds of this weight will be blood. 
About one-fourth of this blood is distributed in the 
heart, lungs, large arteries, and veins; one-fourth in 
the liver; one-fourth in the muscles; and one-fourth 
in other organs. THE BLOOD. 
109 
111. Composition of the Blood.—When blood 
first flows, it appears to the naked eye like a perfectly 
simple red fluid. It is not, however, as simple in com- 
position as it appears, as can be learned by looking at 
a drop of blood under the microscope. It will then 
be seen to be made up of a solid and a liquid portion. 
The liquid, which is colorless, is called plasma; the 
solid part is composed of corpuscles. These corpus- 
cles, or “ little bodies,” are of two kinds—the red cor- 
puscles and the white corpuscles. In Fig. 29 is a view 
Fig. 29.—Red and White Corpuscles of the Blood Magnified, 
of some of the appearances presented by these cor 
puscles, red and white. 
112. The Red Corpuscles.—The red corpuscles 
are flat, circular disks, dimpled on each side like a 110 
FIRST LESSONS IN PHYSIOLOGY. 
shirt-button. In the figure are views of them look- 
ing at them in front and edgeways. They have a 
curious fashion of sometimes sticking together like a 
roll of pennies, as is also shown. A single red corpus- 
cle really looks yellowish; but when many of them 
are seen together they look red. They give to the 
blood its red color. The blood has been compared to 
a stream of water filled with an immense number of 
very little red fishes, the red corpuscles. One drop of 
blood contains as many as a million. 
113. The White Corpuscles.—The white cor- 
puscles are somewhat larger than the red. They are 
usually globular. They will, however, even while 
one is looking at them with the microscope, change 
their shape several times—one moment being globu- 
lar, the next pear-shaped, the next three-cornered, 
and so on. They are colorless, and are less numerous 
than the red corpuscles, healthy blood containing only 
one white corpuscle to about four or five hundred red. 
It is supposed that the white corpuscles become in 
time changed into the red. When the proportion of 
white corpuscles to red is much increased, a serious 
disease is the result. 
114. Clotting or Coagulation.—If fresh blood is 
put into a bowl, it soon becomes like jelly. If it is 
left standing for some hours, it will separate into two 
parts—one a red, solid mass, the clot, and the other a 
clear liquid, which is called serum. The whole proc- 
ess is spoken of as clotting or coagulation. In the 
plasma, or liquid part of blood, a substance called 
fibrin forms. This is made up of very delicate THE BLOOD. 
threads or filaments. These run in all directions like 
an extremely fine net-work. The corpuscles get 
caught in this net-work, and in this way the clot is 
formed. The serum is the plasma with its fibrin 
removed; the clot is equivalent to the corpuscles 
with fibrin added. It is not yet known exactly where 
the fibrin, which plays such an important part in clot- 
ting, originates. It forms in the blood after it has 
left the body. It has been thought probable that it 
is in part, at least, made out of the white corpuscles 
breaking in pieces. 
115. Clotting of Blood in the Living Body.—In 
health, blood does not clot in the living body. It is 
fortunate that this is the case. The smallest islet of 
flesh becomes barren and dead without its supply of 
blood. If a vessel should be stopped by a clot, the 
parts to which the vessel goes would not receive this 
supply. This clotting sometimes occurs in grave dis- 
eases. Clotting sometimes serves a useful purpose 
when blood-vessels are cut or otherwise injured. The 
bleeding is checked by the clots plugging the open 
mouths of the vessels. 
116. Composition of Serum.—Even the serum, or 
liquid part of the blood which separates from the clot, 
is not a simple fluid. It contains more than water. 
It is largely made up of albumen, the same substance 
that is found in the white of egg. This albumen is 
composed of the four great elements carbon, hydro- 
gen, nitrogen, and oxygen, sometimes called albumin- 
oids. Albumen, and substances like it, are found here 
and there all over the body. Our food, out of which 112 
FIRST LESSONS IN PHYSIOLOGY. 
the blood is made, contains also the albuminoid ele- 
ments. Vegetables are largely made up of oxygen, 
hydrogen, and carbon; while most animal food con- 
tains all these, and nitrogen in addition. Some parts 
of vegetables, however, contain all four elements, and 
the fat of animals is composed only of the oxygen, 
hydrogen, and carbon. The serum of the blood can 
be dried, and it will then readily burn. The part 
which burns is chiefly albumen; and in burning, this 
substance gives rise to carbonic acid, water, and am- 
monia. Carbonic acid contains carbon and oxygen; 
water contains hydrogen and oxygen; and ammonia 
contains nitrogen and hydrogen. In burning, the 
albumen breaks up into its different elements, some 
of which unite with oxygen from the air, and, as 
stated, carbonic acid, water, and ammonia are formed. 
Albumen is, as the chemists would say, a body which 
can be burned or oxidized. 
117. Composition of Fibrin.—Fibrin is a sub- 
stance very similar in composition to albumen, al- 
though the two are not identical. It is an albuminoid; 
like albumen, it is composed of carbon, hydrogen, 
nitrogen, and oxygen. Fibrin, albumen, and other 
albuminoids, largely make up the important tissues of 
the body, muscle, nerve, gland, etc. 
118. Water of the Blood.—In one hundred parts 
of serum about ninety parts are water; and in one 
hundred parts of wet corpuscles about fifty-six or fifty- 
seven parts are water. The entire blood contains 
nearly eighty per cent, of water. It is “ thicker than 
water” chiefly because of the immense numbers of THE BLOOD. 
113 
corpuscles which it contains; although the solid mat- 
ters dissolved in the plasma also help to render it 
thicker and heavier. 
119. Mineral Substances in the Blood.—In addi- 
tion to the corpuscles, the fibrin, the albumen, and 
the water, the blood also contains minute quantities 
of minerals or salts. When blood is dried and then 
burned, a small amount of ash will always be left. 
This ash, if examined carefully, will be found to con- 
tain numerous mineral substances, the most important 
of them being iron, potassium, sodium, calcium, chlo- 
rine, sulphur, and phosphorus. These substances, 
although present in such very small quantities, are 
essential to healthy blood. 
120. Uses of the Blood.—The feeding of the tis- 
sues of the body is carried on chiefly by the fluid part 
of the blood. The tissues take nutritive material from 
the blood, and the blood itself is fed from the food 
taken into the stomach. This blood builds bone and 
brain, liver and lungs, marrow and muscle; from it 
are derived bile, tears, saliva, and other secretions. 
Even the vessels which carry the blood are made from 
it. It supplies each tissue with the kind of material 
it needs. It carries oxygen to every part which re- 
quires oxygen. The blood also collects the waste 
matters of the body and conveys them to the organs 
which cast them out. 114 
FIRST LESSONS IN PHYSIOLOGY. 
Syllabus. 
Good blood in proper quantity Usually means good health. 
Only a few tissues, such as the nails and hair, will not bleed when 
stuck or cut. 
Blood can be studied in a living animal in the web of a frog’s 
foot. 
The quantity of blood in the body is about one-thirteenth or one- 
fourteenth of the body-weight. 
Blood is made up of a solid and a liquid portion. The liquid is 
called plasma; the solid part is composed of red and white corpuscles. 
Red corpuscles are flat, circular disks, dimpled on each side. They 
sometimes stick together like a roll of pennies. They give to the 
blood its red color. One drop of blood contains as many as a million. 
White corpuscles are usually globular; but often change their 
shape. 
Healthy blood contains one white corpuscle to about four or five 
hundred red. 
If blood is left standing in a bowl for some hours, it will separate 
into a red, solid mass, the clot, and a clear liquid called serum. 
A substance called fibrin forms in the plasma. This fibrin is made 
up of delicate threads, which constitute a fine net-work, in which the 
corpuscles get caught, and in this way the clot is formed. The serum 
remains behind. 
It has been thought probable that fibrin in part, at least, is made 
out of the white corpuscles breaking in pieces. 
In health, blood does not clot in the living body. 
Clotting sometimes serves a useful purpose when blood-vessels are 
cut or otherwise injured. The bleeding is checked by the clots plug- 
ging the open mouths of the vessels. 
Serum contains more than water. It is largely made up of al- 
bumen. 
Albumen is composed of carbon, hydrogen, nitrogen, and oxygen— 
elements sometimes called albuminoids. 
Food, out of which the blood is made, contains the albuminoid 
elements. 
The serum of the blood can be dried and burned. The part which 
burns is chiefly albumen; and in burning, this substance gives rise 
to carbonic acid, water, and ammonia, partly through union of its 
elements with the oxygen of the air. QUESTIONS FOR REVIEW. 
115 
Fibrin is an albuminoid. 
Fibrin, albumen, and other albuminoids, largely make up the im- 
portant tissues of the body. 
The entire blood contains nearly eighty per cent, of water. 
Blood contains minute quantities of minerals or salts, the most im- 
portant of them being iron, potassium, sodium, calcium, chlorine, 
sulphur, and phosphorus. 
The blood feeds the tissues, and the food taken into the stomach 
feeds the blood. It supplies each tissue with the kind of material it 
needs. 
The blood collects the waste matters of the body and conveys them 
to the organs which cast them out. 
Questions for Review. 
"VVhat is blood ? What has it been called ? 
Where is it found ? 
How do physiologists study blood in a living animal ? 
To what is the quantity of blood- in the body equal ? 
How is this blood distributed ? 
Of what two portions is the blood composed ? 
What are the two kinds of corpuscles called? 
Describe the red corpuscles. 
In what manner do the red corpuscles often come together ? 
What is the color of a single red corpuscle ? 
To what has the blood been compared ? 
How many red corpuscles does one drop of blood contain? 
How do the white corpuscles compare in size with the red? 
What is the shape of the white corpuscles ? 
What is said about the white corpuscles changing shape? 
What is said about their color ? 
How do the white corpuscles compare in number with the red ? 
What becomes of the white corpuscles ? 
What is the result when the white corpuscles increase out of pro- 
portion to the red ? 
What happens if fresh blood be allowed to stand in a bowl? 
Into what two parts does the blood separate ? 
What is the process of separation called ? 116 
FIRST LESSONS IN PHYSIOLOGY. 
What substance is found in the plasma, or liquid part of blood? 
Describe the process by which a clot is formed. 
To what is the serum equivalent ? 
To what is the clot equivalent ? 
What is known about the origin of fibrin ? 
Does blood clot in the healthy living body ? 
What would happen if blood clotted in the living body ? 
What useful purpose is sometimes served by clotting ? 
Of what is serum largely composed ? 
Of what elements is albumen composed ? 
What are these elements sometimes called ? 
Where is albumen found ? 
Does the food contain albuminoid elements ? 
Of what are vegetables largely composed ? 
What does animal food contain ? 
What is said of drying and burning serum ? 
What substance chiefly burns ? 
In burning, to what does albumen give rise ? 
What is the composition of carbonic acid, of water, and of am- 
monia? 
How would the chemists describe albumen ? 
What is fibrin ? Of what is it composed ? 
What are largely made up by the fibrin, albumen, and other 
albuminoids ? 
What is the proportion of water in serum ? 
What is the proportion of water in wet corpuscles ? 
What is the per cent, of water in the entire blood ? 
What makes blood “ thicker than water ” ? 
What is contained in the ash of blood ? 
How are the tissues fed ? 
How is the blood fed ? 
Name some of the uses of the blood. 
What is collected by the blood ? CHAPTER XI 
THE CIRCULATION OF THE BLOOD 
121. Machinery for Distributing the Blood.— 
As the blood builds every tissue, the body must have 
machinery to distribute this blood. The heart is the 
pump which propels, and the blood-vessels are the pipes 
which convey, the red fluid of life to every little parti- 
cle of tissue. The blood is constantly travelling round 
and round to every part of the system. This journey 
of the blood through the body is called the circulation, 
the word circulate meaning to “move round.” In 
ancient times it was said that “ all roads led to Rome,” 
because Rome was the centre of the world’s activities. 
In like manner, in regard to the circulation, all roads 
lead to the heart. The roads by which the blood travels 
are blood-vessels of three kinds,called arteries,veins, and 
capillaries. The blood goes out of the heart and finds 
its way through these vessels back to the heart again. 
122. The Heart.—The heart (Figs. 80,81) is a hollow 
organ, situated in a space in the chest between the two 
lungs. It is conical in shape, its pointed end, or apex, 
hanging downwards. Its usual weight is ten to twelve 
ounces. It is not a single chamber or cavity. It is di- 
vided, in the first place, from above downwards into a 118 
FIRST LESSONS IN PHYSIOLOGY. 
right and left half; and then each of these halves is again 
subdivided into an upper 
and lower cavity. If 
the head is placed on 
the left side of the chest, 
a peculiar double sound, or 
rather two sounds, some- 
thing like lubb dup, lull 
dup, can be heard. To 
hear these sounds best, 
the listening ear should 
be about on a level with 
the fifth rib, or over the 
space between the fifth 
and sixth ribs, and a lit- 
tle to the left of the 
breast-bone. These are 
the sounds of the heart, 
which is ceaselessly working. 
Fig. 30. 
The Heart and Large Blood-vessels. 
123. Valves of the Heart.—The word vabecomes 
from a Latin word which means “ folding-doors.” A 
valve is usually a little lid or door of some kind, so 
made as to permit a fluid to pass in one direction, hut 
not to come back. In the common pump is a valve 
which allows the water to come up, and then closes to 
prevent its return, so that it is compelled to flow out 
of the spout. Between the upper and lower cavities 
on each side of the heart, and also between the lower 
cavities and the vessels which go out from them, are 
valves, which allow the blood to flow forward, but 
prevent it getting back again, so that the circulation 
is kept up steadily in one direction. THE CIRCULATION OF THE BLOOD. 
119 
124. Arteries.—The term artery comes from Greek 
words meaning “ to contain air.” The ancients be- 
lieved that the arteries were air-tubes, because they 
usually found them empty after death. The first and 
largest of the arteries is given off directly from the 
Fig, 31.—A View of the Chest, Showing the Heart, the Lungs, and the Large 
Blood-vessels. 
left lower cavity of the heart. It is called the aorta, 
from Greek words meaning to “ support,” because it is 
supported or suspended from the heart. It goes up 
from the heart, makes a great curve from right to 
left, and then descends through the trunk in front of 120 
FIRST LESSON’S IN PHYSIOLOGY. 
the backbone. It sends off branches to all parts of 
the body. In Fig. 32 is a view of the aorta and 
some of its branches. The first 
of these go to the organs in the 
chest, abdomen, and pelvis. A 
large artery goes to each leg, 
dividing and subdividing until 
the toes are reached. Each arm 
is supplied with a main artery 
also, which divides at the elbow 
into two branches, and these 
subdivide again and again down 
to the very finger-tips. In Fig. 
33 is a view of the arteries of 
the arm and forearm and their 
subdivisions. If the ends of the 
fingers are placed along the front 
of the wrist, near its thumb 
side, a steady beat will be felt. 
This is the impulse of the 
blood in an artery. It is the 
“ pulse ” which the doctor feels. 
On the temples this impulse can 
also be made out. It could be 
felt in hundreds of places, if 
the blood-vessels were not so 
covered by the tissues. A large 
artery goes up each side of the 
neck, and this has an internal 
branch which passes through a hole in the skull to the 
brain, and an external branch which supplies the neck 
and face, as shown in Fig. 34. 
Fig. 32. 
The Aorta and its Branches. THE CIRCULATION OF THE BLOOD. 
121 
125. The Veins.—The vessels which bring the 
blood back to the heart are called 
veins, the Latin vena meaning a 
“ pulse,” or “ vein.” The arteries 
begin in one great vessel, the aorta; 
the veins end in two great vessels, 
both of which open into the right 
upper chamber of the heart. Veins, 
like arteries, are found in all parts 
of the body. Instead of starting as 
large vessels, like the arteries, they 
begin as minute tubes, and come 
together to form larger and larger 
trunks. They have thinner walls 
than the arteries. The veins have 
valves, like little watch-pockets, 
along their inner walls. They open 
the way the blood travels (Fig. 35). 
Their mouths are always towards 
the heart. 
126. The Capillaries.—Arte- 
ries do not open into veins, nor 
veins into arteries; but commu- 
nication between them is made 
by another set of very fine vessels, 
the capillaries, from the Latin capil- 
lus, a hair. All the arteries of the body may be 
said to end, and all the veins to begin, in these capil- 
laries. 
Fig. 33. 
Arteries of the Forearm. 
127. Contractions of the Heart.—The heart is a 
muscular organ, and it is the property of a muscle to 122 
FIRST LESSONS IN PHYSIOLOGY. 
contract. The muscular fibres which compose the 
walls of the heart run in various directions around 
its cavities. When these fibres contract, they squeeze 
together the heart-walls. If a hollow India-rubber 
ball, with a hole in it, is filled with water, and is 
firmly grasped and twisted in the hand, the water 
Fig. 34—The Arteries of the Head and Face. 
will be driven out through the opening. The hand 
and fingers contain many muscles, and it is through 
their contractions that the force which expels the 
water is exerted. During the passage of blood 
through the heart, a series of squeezings or contrac- 
tions takes place. THE CIRCULATION OF THE BLOOD. 
123 
128. Description of the Course of the Circulation. 
—All the blood from the capillaries of the 
body is collected by veinlets and veins, and is 
carried to the upper cavity of the right side 
of the heart. As soon as this cavity is full, its 
walls begin to contract, and the blood within 
is squeezed through the valve into the lower 
cavity of the same side. The valve between 
the two cavities is composed of little flaps, 
and, as the blood fills the lower cavity, it 
gets behind these flaps and pushes them 
shut. From the right lower cavity of the 
heart a large vessel, called the pulmonary 
or lung artery, goes out and sends branches 
to both lungs. Where this artery begins, 
the opening is guarded also by a valve. The walls 
of the heart-cavity squeeze together, and the blood 
rushes forward into the artery, and is prevented 
by the valve from reflowing. Carried by the pul- 
monary artery and its branches, the blood is distrib- 
uted to millions of capillaries in the lungs. From 
these it passes into pulmonary or lung veins, the 
largest of which finally convey it to the upper of the 
two cavities of the left side of the heart. The journey 
through the left heart is very much like that through 
the right. The upper cavity contracts and forces the red 
stream onward through a valve into the lower. This 
left lower cavity next contracts. The blood cannot flow 
back, so it pushes forward with a great wave into the 
aorta, the opening into which is also guarded by a valve. 
On and on the blood travels until the capillaries of all 
parts of the body, except the lungs, are reached. 
Fig. 35.— A 
Vein Open- 
ed so as to 
Show the 
Valves in 
Parts. 124 
FIRST LESSONS IN PHYSIOLOGY. 
129. The Circulation through the Liver.—The 
liver is supplied with blood for its nourishment by 
branches of the aorta. In addition, the blood which 
circulates in the stomach, intestines, and some other 
organs, is collected by a large vein and carried into 
the liver. The liver acts upon the blood, so as to 
render it better fitted for the uses of the body. It 
is thought that the liver destroys a poisonous mate- 
rial which forms in the blood in other parts of the sys- 
tem. The liver also manufactures sugar to be used by 
the system. After the blood has been changed in the 
liver, it is collected by veins and conveyed to the right 
side of the heart. 
130. The Spleen.—The spleen, a dark, red organ, 
about five inches long, and weighing about six or seven 
ounces, is situated to the left of the stomach. It has 
no ducts or canals. Its exact functions are not known. 
Things are carried to the spleen by blood-vessels, and 
after they have been changed in the spleen they are 
probably carried away in the blood again. 
131. How the Tissues are Supplied by the 
Blood.—The walls of the capillaries are very thin. 
Everywhere these capillaries surround little islets of 
tissue. Nutritive materials from the blood soak 
through the thin walls of the capillaries into these 
little islets. If a bladder containing water, in which 
sugar has been dissolved, is placed in a vessel of pure 
water, the water in the vessel after a short time will 
taste of the sugar. The dissolved sugar has passed 
through the membrane. In a similar way materials 
pass out of the blood into the tissues. SYLLABUS. 
125 
The blood is distributed to the tissues by the heart and blood- 
vessels. 
The journey of the blood through the body is called the circulation. 
Blood-vessels are of three kinds, called arteries, veins, and capil- 
laries. 
The heart is a hollow organ in the chest between the two lungs. 
It is divided into a right and left half, and each of these halves is 
subdivided into an upper and lower cavity. 
The sounds of the heart can be best heard about on a level with 
the fifth rib, or between the fifth and sixth ribs, a little to the left of 
the breast-bone. 
Between the upper and lower cavities on each side of the heart, 
and also between the lower cavities and the vessels which go out 
from them, are valves. 
The ancients believed that the arteries were air-tubes, because they 
usually found them empty after death. 
The largest artery, called the aorta, is given off directly from the 
left lower cavity of the heart. It sends off branches to all parts of 
the body—to chest, abdomen, pelvis, legs, arms, neck, face, brain, etc. 
Veins bring the blood back to the heart. 
The veins end in two great vessels, both of which open into the 
right upper chamber of the heart. 
Veins have thinner walls than the arteries. 
The veins have valves like little watch-pockets along their inner 
walls. 
Communication is made between the arteries and veins by a set of 
very fine vessels called capillaries. 
The muscular fibres which compose the walls of the heart contract 
and squeeze together the heart-cavities, and thus force onwards the 
blood. 
All the blood from the capillaries is collected by veins and carried 
to the right side of the heart; it passes from the right upper to the 
right lower cavity, and thence by way of the pulmonary artery to 
the lungs ; from the lungs it is conveyed by the pulmonary veins to 
the left upper cavity of the heart; it moves onward through the left 
cavities of the heart into the aorta, and thence to the general system. 
The blood which circulates in the stomach, intestines, and some 
Syllabus. 126 
FIRST LESSONS IN PHYSIOLOGY. 
other organs is collected by the portal vein and carried into the 
liver. 
The liver destroys a poisonous material which forms in the blood 
in other parts of the system. It is also a source of sugar. 
The spleen, a dark, reddish organ, about five inches long, and 
weighing about six or seven ounces, is situated in the upper part of 
the abdomen, to the left of the stomach. Its exact function is not 
known. 
The tissues take from the fluid portion of the blood what they need 
for their nourishment. 
Nutritive materials soak through the thin walls of the capillaries 
into little islets of tissue. 
Questions for Review. 
What propels the blood ? 
What conveys it to the tissues ? 
What is the journey of the blood through the body called? 
What are the three kinds of blood-vessels ? 
What is the heart ? 
Where is it situated ? 
What is its usual weight ? 
Into how many cavities is it divided ? 
Describe the sounds of the heart. 
Where are these sounds best heard ? 
From what is the word valve derived ? 
What is a valve ? Give an example of a valve. 
What valves are found in the heart ? 
From what is the term artery derived ? 
Where is the first and largest artery ? 
Why is it called the aorta ? 
Describe the course of the aorta. 
To what organs do the first branches of the aorta go ? 
How are the legs and arms supplied with arteries ? 
Where can the impulse of the blood in an artery be felt most 
readily ? 
At what other points can it be felt ? 
Why cannot the pulse be felt in hundreds of places where arteries 
are found ? QUESTIONS FOR REVIEW. 
127 
Describe the course of the arteries which go to the brain, neck, 
and face. 
What are the vessels which bring the blood back to the heart 
called? 
How do the veins end ? How do they begin and increase ? 
How do their walls compare with those of the arteries ? 
Describe the valves of the veins. 
What are the capillaries ? 
Of what sort of tissue is the heart composed ? 
How do the muscular fibres of the heart run ? 
What is the effect of the contraction of these fibres ? 
Illustrate by a hollow India-rubber ball the method in which mus- 
cular action causes fluid to be expelled from a cavity. 
What takes place during the passage of blood through the heart ? 
How is the blood from the capillaries of the body collected ? 
To what cavity of the heart is the blood carried by the veins ? 
Describe the journey of the blood through the right side of the 
heart. 
What large vessel goes out from the right lower cavity of the heart 
to the lungs ? 
How is the opening of this vessel guarded ? 
Describe the distribution of the blood to the capillaries of the 
lungs. 
Into what does the blood pass from the capillaries of the lungs ? 
To what cavity of the heart do the pulmonary veins convey the 
blood ? 
Describe the journey of the blood through the left side of the 
heart and the general system. 
How is the liver supplied with blood for its nourishment? 
What is done by the portal vein ? 
What are some of the functions of the liver? 
What becomes of the blood after it has been changed in the liver ? 
What is the spleen ? Where is it situated ? 
What is known about its functions? ■ 
Describe the manner in which nutritive materials get into the 
tissues from the capillaries. 
Illustrate by a bladder containing water in which sugar has been 
dissolved, CHAPTER XII 
FOOD. 
132. Why we Eat.—A witty writer has said that 
some people eat to live and others live to eat. It is 
certain that unless we eat we cannot live. Our tissues 
are constantly wasting, because every part of the body 
is constantly at work. Walking, writing, breathing, 
thinking, lead to waste. This waste must be made 
good by what we eat and drink, by what we take into 
the system. We eat that we may make blood, and 
from the blood each part of the body takes something 
to keep it alive and growing. What we eat does not 
go at once into the blood; it must first be got ready. 
It is true that doctors sometimes throw medicine, 
liquid food, or even fresh blood itself, directly into a 
patient’s blood; but this is something unusual and 
unnatural, and it is only done in extreme sickness, 
and when food cannot be taken in ordinary ways. 
133. Food.—Anything which goes to nourish the 
body, which is used to make good its wear and waste, 
is food. It might be said that food is anything we 
eat or drink, were it not that we sometimes take 
substances into our mouths and stomachs which are FOOD. 
129 
not food; and some, indeed, which do more harm than 
good to the body. Eggs, milk, meat, bread, sugar, 
butter, salt, and water are well-known articles which 
contain the essentials of a real food; on them one 
could live, grow, and develop. 
134. Digestion.—Digestion must be performed be- 
fore food, of whatever kind it may be, becomes blood. 
The word digestion means the act of dissolving or 
separating into parts. It is a process of breaking up 
and changing the food until it gets just right for the 
blood. 
135. The Different Classes of Food-Stuffs.— 
We have learned that albumen, of which the serum 
of the blood is mainly composed, contains the four 
great elements, carbon, hydrogen, nitrogen, and oxygen; 
and also that the food which makes the blood, and the 
tissues and organs of the body, are largely formed of 
these elements. Foods, or food-stuffs, are of different 
kinds, according to the proportions or arrangement of 
these elements. Nitrogenous food-stuffs contain these 
four elements ; but they are most important because of 
their nitrogen. They are the only forms of food which 
contain nitrogen. They are sometimes called albu- 
minoids, because of the albumen which abounds in 
them. The best examples of nitrogenous food are found 
in lean meat, eggs, and milk. Sugars and starches, 
which constitute another class of food-stuffs, contain 
carbon, hydrogen, and oxygen, with a large proportion 
of the last. Sugar is chiefly obtained from fruits and 
vegetables, but sometimes comes from the animal world, 
as when obtained from honey and milk. Starch is abun- FIRST LESSONS IN PHYSIOLOGY. 
dant in such food as wheat, corn, rye, rice and pota- 
toes. Fats and oils, a third kind of food, also contain 
carbon, hydrogen, and oxygen, but comparatively 
little of the last. They also are derived both from 
the animal and vegetable world; for example, the fat 
of meats, of butter, and of milk from the animal 
kingdom; from the vegetable, olive oil, palm oil, and 
cocoa butter. Mineral substances, such as common 
salt, lime, and iron, form a necessary part of food, 
although they are not needed in large quantities. 
Our chief drink, water, is one of the most important 
articles of food. It makes up the greater part of 
the weight and bulk of the body. 
136. Remarks on the Different Kinds of Food.— 
Food-stuff’s get into the blood after undergoing cer- 
tain changes. Our food should contain different 
articles in proper proportion. Milk, and food prepared 
from it, are among the best articles of diet, because 
milk contains every one of the different classes of 
food,—nitrogenous, sugary, fatty, and mineral, and a 
good supply of water. It is usually easy of digestion. 
If compelled to live on a single article, milk would 
be the best. The term “flesh-food” is sometimes 
applied to the different kinds of meat—beef, mutton, 
pork, fowl, fish, etc. These, like eggs, abound in nitro- 
genous material. Breads supply us with plenty of 
sugary and starchy matters. They, however, contain 
also gluten, which is a form of nitrogenous or albu- 
minous food. The potato is composed of water, starch, 
and a little albumen. Fruits are largely made up of 
water and sugar, and are useful as food, as well as FOOD. 
131 
agreeable to the taste. What is called a “mixed 
diet” is the best. Body and mind are kept in the best 
condition by using both animal and vegetable food. 
137. Quantity of Food Required.—The quantity 
of food required to maintain health varies greatly ac- 
cording to certain circumstances, such as age, activity, 
season, and climate. The young need more than the 
old. Those who are active, who work hard either 
physically or mentally, require a large supply of good 
food. In cold weather and cold climates more food, 
and of a stronger quality, is needed than in warm 
seasons and hot climates. Animal food should not 
be taken oftener than twice daily. The amount of 
animal and vegetable food combined, should not ex- 
ceed thirty ounces in the twenty-four hours; and for 
the majority of persons an average of twenty-four 
ounces of mixed solid food, a third only of which 
should be animal, is sufficient. The amount of fluid 
taken in any form should not exceed the average of 
twenty-four ounces daily.* 
138. Cooking.—Good cooking is of great impor- 
tance. The best food may be rendered almost worth- 
less by bad preparation. Articles are cooked to fit 
them for digestion and improve them in taste. Some- 
times cooking is necessary to make food safe. A 
minute worm called the trichina spiralis, or “spiral 
hair-like worm,” sometimes is present in different 
forms of pork, and in beef. If the pork or beef is 
eaten raw or underdone, this worm may get into the 
human body and produce a painful disease. 
* B. W. Kichardson’s “ Diseases of Modern Life.” 132 
FIRST LESSONS IN PHYSIOLOGY. 
139. When and How to Eat.— Persons in ordi- 
nary health should eat at regular intervals. Three 
meals a day, from five to six hours apart, should be 
taken. Eating between meals should be avoided. 
The stomach needs to rest between its efforts at 
digestion. We should eat slowly, carefully chewing 
solid food. We should be cheerful while eating. 
The brain and the stomach cannot both be worked 
hard at the same time without injury to one or the 
other; therefore, we should not think deeply, nor allow 
our minds to be excited, while eating. Pleasant con- 
versation assists digestion. The old saying that one 
should leave the table feeling hungry is not true; 
but, on the other hand, we should not eat until we are 
uncomfortable. A disease known as dyspepsia, which 
means “ difficult digestion,” is usually caused by errors 
of diet—by taking food at irregular hours, or of im- 
proper quality or quantity, or by not devoting suffi- 
cient time to eating and drinking. 
140. Drinks.—Tea, coffee, and cocoa, when prop- 
erly used, are admirable drinks and very serviceable, 
particularly for grown people. They soothe and stim- 
ulate the nervous system, and prevent the tissues 
from wasting too rapidly. They should not be taken 
in excess. One cup of each a day is enough. Alco- 
holic drinks, such as wine, ale, beer, brandy, and 
whiskey, have their uses, but should not be employed 
as common drinks. When the system is much re- 
duced by disease or by accident, they may be of much 
service. Their use should be directed by physicians. 
141. Pure Water.—Of all drinks, pure water is the SYLLABUS. 
best. By pure water we mean water free from in- 
jurious impurities. Absolutely pure water is not 
found in nature, but can be obtained by carefully con- 
densing steam. Rain-water, where it falls in the 
country, is a good example of a soft and comparatively 
pure water. If water is acted upon by sewer-gas, or 
receives foul matters of any kind, it becomes a source 
of disease. Water obtained from lakes or rivers 
should be carefully filtered before being used. 
Syllabus. 
The tissues of the body are constantly wasting because every part 
of the body is constantly at work. This waste is made good by what 
we eat and drink. 
We eat that we may make blood. 
Anything which goes to nourish the body, which is used to make 
good its wear and waste, is food. 
Eggs, milk, meat, bread, sugar, butter, salt, and water contain the 
essential of a real food. 
Digestion is a process of breaking up and changing the food until 
it gets just right for the blood. 
Foods, or food stuffs, are of different kinds, according to the pro- 
portion or arrangement in them of the four great elements, carbon, 
hydrogen, nitrogen, and oxygen. 
Our food should contain the different food-stuffs in proper propor- 
tion. 
If compelled to live on a single article of diet, milk would be the 
best, because it contains every one of the different classes of food- 
stuffs, and is usually easy of digestion. 
“ Flesh-food,” such as beef, mutton, pork, fowl, and fish, abounds in 
nitrogenous material. 
Breads supply us with plenty of sugary and starchy matters, and 
contain also gluten, which is a form of nitrogenous food. 
The potato is composed of water, starch, and a little albumen. 134 
FIRST LESSONS IN PHYSIOLOGY. 
Fruits are largely made up of water and sugar. 
A mixed diet, one containing both animal and vegetable food is 
the best. 
The young need more food than the old; the active require a large 
supply. 
In cold weather and cold climates, more food, and of a stronger 
quality, is needed than in warm seasons and hot climates. 
Nitrogenous food-stuffs contain these four elements ; but they are 
most important because of their nitrogen. They are sometimes 
called albuminoids, because of tbe albumen which abounds in them. 
Lean meat, eggs, and milk are the best examples of nitrogenous 
food. 
Sugars and starches, another class of food-stuffs, contain carbon, 
hydrogen, and oxygen, with a large proportion of the last. 
Sugar is chiefly obtained from fruits and vegetables, but some- 
times from honey, milk, and other animal sources. 
Fats and oils also contain carbon, hydrogen, and oxygen, but com- 
paratively little of the last. They also are derived both from the ani- 
mal and vegetable world, from milk, butter, olive oil, etc. 
Mineral substances, such as common salt, lime, and iron, form a 
necessary, but small part of our food. 
Water is one of the most important articles of food. 
Animal food should not be taken more than twice daily. 
The amount of animal and vegetable food combined should not 
exceed twenty-four to thirty ounces in the twenty-four hours, a 
third only of which should be animal. 
The amount of fluid taken in any form should not exceed the av- 
erage of twenty-four ounces daily. 
Good cooking is of great importance. 
Articles are cooked to fit them for digestion and improve them in 
taste. 
Sometimes cooking is necessary to make food safe. A minute worm, 
called the trichina spiralis, sometimes is present in raw meat; and if 
the meat is eaten raw or underdone, this worm may get into the 
human body and produce a painful disease. 
Three meals a day, from five to six hours apart, should be taken. 
We should eat slowly, and we should be cheerful while eating. 
We should neither leave the table hungry, nor should we eat 
until we are uncomfortable. 
Dyspepsia is a disease usually caused by errors of diet. QUESTIONS FOR REVIEW. 
135 
Tea, coffee, and cocoa are admirable and serviceable drinks, but 
should not be taken in excess. 
Alcoholic drinks should not be employed, except for special pur- 
poses, and under the direction of physicians. 
Of all drinks, water free from injurious impurities is the best. 
Questions for Review. 
Why are the tissues of the body constantly wasting ? 
How is this waste made good ? 
Why do we eat? 
What must take place before what we eat gets into the blood? 
Are substances ever introduced directly into the blood ? 
Give illustrations. 
Define the word food. 
Why do we not define food as anything that we eat or drink ? 
Name some well-known articles which contain the essentials of a 
real food. 
What is the meaning of the word digestion? 
What is the process of digestion ? 
What four elements does the albumen of the blood contain ? 
Does the food also contain these elements? 
What different kinds of food or food-stuffs are known ? 
What do nitrogenous food stuffs contain ? 
What are they sometimes called, and why? 
What do sugar and starches contain ? 
From what is sugar obtained? 
In what kind of food does starch abound? 
What do fats and oils contain ? 
From what are fats and oils derived? 
What is said of mineral substances as articles of food ? 
What is said of water ? 
To be most useful, what should our food contain ? 
Why is milk one of the best articles of diet? 
To what is the term “ flesh-food ” applied ? 
In what material does “ flesh-food” abound? 
What sort of matters are supplied by breads? 
What form of nitrogenous food is found in breads ? 136 
FIRST LESSONS IN PHYSIOLOGY. 
What is the composition of fruits ? 
What is the best diet ? 
How is the quantity of food required to maintain health varied ? 
Do the young or old need most food ? 
What do the active require? 
What effect has weather and climate ? 
How often daily should animal food be taken? 
What amount of animal and vegetable food combined should be 
taken in twenty-four hours ? 
What amount of fluid should be taken daily ? 
Why are articles cooked ? 
Is cooking ever necessary to make food safe ? Illustrate. 
How many meals a day should be taken ? 
Why should eating between meals be avoided ? 
How should we eat ? 
What should be our condition of mind while eating ? 
What is the meaning of the word dyspepsia ? How is it usually 
caused ? 
What is said of tea, coffee, and cocoa ? 
What is said of alcoholic drinks ? 
What is the best of all drinks ? 
Is absolutely pure water found in nature ? 
What is a good example of a soft and comparatively pure water? 
How may water become a source of disease ? 
What should be done with water obtained from lakes and rivers 
before using it ? CHAPTER XIII. 
DIGESTION. 
142. The Organs of Digestion.—The organs of 
digestion are the different parts of the alimentary or 
food canal, and the glands communicating with it. 
This canal is a long tube, which is at some places 
wide and at others narrow, at some straight and at 
others twisted. It begins as the mouth and throat. 
In the back part of the chest it is a narrow, straight 
tube, the gullet or oesophagus, the word oesophagus 
meaning “food-carrier.” It continues into the abdo- 
men as the large bag or pouch called the stomach, and 
as the intestines it becomes a long tube, wound and 
turned upon itself in a curious fashion. 
143. What Takes Place in the Mouth.—When 
liquid food is taken into the mouth, it leaves it very 
quickly, passing by way of the throat and gullet to 
the stomach. If the food is solid or partly solid, it is 
chewed by the teeth and acted upon by the secretions 
of the mouth. The mucous membrane of the mouth 
is full of little glands which pour out a watery fluid 
which mixes with the food. Three pairs of large 138 
FIRST LESSONS IN PHYSIOLOGY. 
glands also pour their secretion, called saliva, into the 
mouth. The largest of the three is the parotid gland, 
which is beneath the skin in front and below each ear. 
The word parotid means “ near the ear.” One of the 
other two is situated just 
beneath the back part of 
the lower jaw, and the other 
in the floor of. the mouth 
under the tongue. Saliva 
has the peculiar property 
or function of converting 
starch into sugar. This turn- 
ing of starch into sugar is 
one of the useful processes of 
digestion. Sugar, being more 
soluble than starch, will go 
through the membranes 
and get into the blood more 
readily than starch. After 
the food has undergone di- 
gestion in the mouth, it 
is swallowed, and passes 
through the gullet to the 
stomach. This gullet or 
oesophagus has a muscular 
coat which contracts around the food, forcing it onward 
and preventing it from returning. 
an, cu 'T . 
The Stomach and Intestines. 
144. Digestion in the Stomach.—The stomach is 
a large bag or pouch situated in the upper part of the 
abdomen. In the walls of the stomach are numerous 
glands. Most of these glands secrete an acid fluid DIGESTION. 
139 
which is called the gastric juice, or juice of the stomach. 
"When the food reaches the stomach an active flow of 
this juice takes place. The food breaks up and dis- 
solves more than it did in the mouth. This breaking- 
up process is partially due to the action of the gastric 
juice, and partly to a churning movement of the 
stomach. The saliva acts particularly on the starchy 
food. The gastric juice acts most rapidly and strongly 
on nitrogenous or albuminoid substances, such as 
meats, eggs, etc. It is supposed also that some saliva 
flows down into the stomach, and acts upon such 
starchy food as may have escaped its action above. 
The food, after undergoing these processes in the 
stomach, becomes a soft, pulpy, grayish mass, which 
is often called chyme, from a Greek word meaning 
“juice.” While the food is digesting in the stomach, 
it is prevented from escaping by two rings, one at the 
entrance and the other at the outlet of the stomach. 
The ring at the outlet of the stomach, at the end 
which opens into the intestines, is called the pylorus, 
this word meaning “gate-keeper.” It guards the gate 
from the stomach to the intestines. 
145. Digestion in the Small Intestine.—As diges- 
tion in the stomach is completed, the pylorus relaxes, 
and allows the food to pass into the small intestine, a 
tube much twisted upon itself and about twenty-five 
feet long. In the walls of the small intestine are little 
glands which secrete an alkaline fluid, the intestinal 
juice. The intestinal juice keeps the food-pulp moist, 
and probably helps to remove an excess of acidity. 
Stretching across the abdomen, behind the stomach, is 140 
FIRST LESSONS IN PHYSIOLOGY. 
a long, thin gland, the pancreas or sweet-bread. It 
secretes the pancreatic juice, which is poured by a 
duct into the small intestine near the stomach. This 
j uice acts strongly upon the fats and oils of the food. 
Like saliva, it also has some power of converting 
starch into sugar, and acts upon nitrogenous food, 
but not with the same energy as gastric juice. Still 
another digestive j uice, and a very important one, acts 
upon the food-pulp in the small intestine. This is a 
greenish-yellow liquid, called bile. It is secreted by 
the liver, the largest gland in the body, which is situ- 
ated in the upper part of the right side of the abdo- 
men. A duct or canal from the liver unites with 
the duct from the pancreas, and the pancreatic juice 
and bile are poured into the small intestine at the 
same place. The bile, like the pancreatic juice, acts 
particularly upon the fats and oils, and to some extent 
upon starchy food. Sweet oil and water will not mix 
well, but if they are shaken up with a little pancreatic 
juice and bile a uniform creamy mixture is produced. 
A similar effect is brought about by the action of 
pancreatic juice and bile upon the food in the small 
intestine. 
146. Chyle.—The food, which left the stomach as 
chyme, after it has been acted upon by the intestinal 
juice, the pancreatic juice, and the bile, becomes con- 
verted into a thick, milky fluid which is called chyle, 
a name derived from a Greek word meaning “juice.” 
The nutritious portions of the food are now ready to 
be taken into the blood. 
14:7. Absorption.—Absorption is tire process by DIGESTION. 
141 
which substances are 
taken up and carried 
into the blood. Absorp- 
tion is performed chiefly 
by two sets of vessels, (1) 
the lacteals or lymphatics, 
and (2) the blood-vessels. 
148. Lacteals.—The 
mucous or lining coat of 
the small intestine is cov- 
ered with little projec- 
tions or eminences called 
villi, from the Latin 
word villus, which means 
a “ tuft of hair.” In these 
villi minute tubes called 
lacteals, from lac, “milk,” 
terminate. Thousands of 
these little pipes open 
into the intestines by way 
of the villi. They absorb 
from the creamy mass 
which is passing through 
the intestine what is 
needed, to strengthen the 
blood. 
149. The Thoracic 
Duct.—Leaving the in- 
testine, the lacteals pass 
through numerous glands 
in the abdomen, and then 
Fig. 37. 
The Thoracic Duct and Lymphatics. 142 
FIRST LESSONS IN PHYSIOLOGY. 
come together into one common duct called the thoracic 
duct, which is a feeding-pipe to the blood. This duct, 
which is about as large as a goose-quill, and eighteen 
to twenty inches long, passes upward through the 
abdomen and chest in front of the backbone. It is 
called the thoracic duct because its course is chiefly 
in the back part of the chest or thorax. It pours 
its contents into a big vein a little above the heart. 
150. Lymphatics. — The lacteals are a part of a 
system of vessels called lymphatics. These lymphatics 
are tubes or vessels distinct from arteries, veins, and 
capillaries. They usually run along near the veins. 
They do not start, like the blood-vessels, from a great 
pumping heart; but they spring up here and there all 
over the body, uniting from time to time to form larger 
vessels. They carry a colorless fluid called lymph. 
The arteries and capillaries sometimes convey to the 
tissues more nutritive material than the tissues can at 
the time use. The lymphatics take up this surplus, 
but valuable, material; and thus keep it from doing 
harm or going to waste. They finally join with the 
lacteals to empty into the thoracic duct. Along the 
course of the lymphatics are little roundish or flattened 
bodies called lymphatic glands. When one has a 
cold, the lymphatic glands near the surface sometimes 
swell and become hard lumps. 
151. Absorption Directly into the Blood.—Some 
things get into the blood from many places besides 
through the lacteals and lymphatics. Sugar, for in- 
stance, may pass into blood-vessels almost anywhere 
along the alimentary canal, because it dissolves so SYLLABUS. 
143 
readily and thoroughly. Water also, which is a very 
necessary part of our food, can slip into the blood 
almost anywhere. Little thin-walled blood-vessels, 
which are in the villi, take up some of the chyle. 
152. The Large Intestine.—The last portion of 
the alimentary canal is the large intestine. It is from 
two to two and a half inches wide and about five feet 
long. Some things which are taken into the alimen- 
tary canal as food and drink are not made use of at 
all; they cannot be or are not digested and taken up 
so as finally to enter the blood. These pass off by way 
of this large intestine. Water is certainly absorbed 
by the large intestine, and some digestion may go on 
in it, but mostly it acts as a channel and temporary 
receptacle for undigested matters, which are finally 
cast out. 
Syllabus. 
The organs of digestion consist of the different parts of the ali- 
mentary or food canal and the glands communicating with it. 
The different parts of the alimentary canal are the mouth and 
throat, the gullet or oesophagus, the stomach, and the intestines. 
Liquid food passes quickly, by way of mouth, throat, and gullet, 
to the stomach. 
Solid or partly solid food is chewed by the teeth and acted upon by 
the secretions of the mouth. 
The secretions of the mouth are a watery fluid poured out by little 
glands in the mucous membrane of the mouth, and a fluid called 
saliva, which is secreted by three pairs of large glands. 
Saliva converts starch into sugar; and sugar, being more soluble 
than starch, will go through the membranes and get into the blood 
more readily than starch. 144 
FIRST LESSONS IN PHYSIOLOGY. 
After the food has undergone digestion in the mouth, it is swal- 
lowed, and passes through the gullet, or oesophagus, to the stomach. 
In the walls of the stomach are numerous glands, most of which 
secretes an acid fluid called the gastric juice. 
The gastric juice acts particularly on nitrogenous or albuminoid 
substances, such as meat, eggs, etc. 
While the food is digesting in the stomach, it is prevented from 
escaping by two rings, one at the entrance and the other at the out- 
let of the stomach, the latter being called the pylorus, or “ gate- 
keeper.” 
The food passes from the stomach into the small intestine, in the 
walls of which are little glands which pour out an alkaline fluid, the 
intestinal juice. This juice keeps the food-pulp moist, and probably 
helps to remove an excess of acidity. 
The pancreas, or sweet-bread, secretes the pancreatic juice, which 
is poured into the small intestine near the stomach. 
The pancreatic juice acts strongly upon the fats and oils of the 
food, and to some extent upon starch and nitrogenous food. 
A greenish-yellow liquid called bile is secreted by the liver, and 
poured into the small intestine at the same place as the pancreatic 
juice. 
The bile also acts particularly on the fats and oils, but also has some 
power to digest starchy food! 
The food which left the stomach as chyme, after it has been acted 
upon by the intestinal juice, the pancreatic juice, and the bile, 
becomes converted into a thick, milky fluid, which is called chyle. 
Absorption, the process by which substances are taken into the 
blood, is performed either by lacteals or lymphatics, or by the blood- 
vessels themselves. 
The mucous or lining coat of the small intestine is covered with lit- 
tle projections or villi, in which minute tubes called lacteals terminate. 
The lacteals absorb from the chyle nutritious material for the 
blood. 
After passing through numerous glands, the lacteals come together 
into the thoracic duct, which is a feeding-pipe to the blood. 
The thoracic duct passes upwards, and pours its contents into a big 
vein a little above the heart. 
The lacteals are a part of a system of vessels called lymphatics, 
which usually run along near the veins, and carry a colorless fluid 
called lymph. QUESTIONS FOR REVIEW. 
145 
The arteries and capillaries sometimes convey to the tissues more 
nutritive material than the tissues can at the time use. The lymph- 
atics take up this surplus, but valuable, material. 
The lymphatics finally join with the lacteals to empty into the 
thoracic duct. Along the course of the lymphatics are little round- 
ish or flattened lymphatic glands. 
Some substances, as sugar, water, some of the chyle, etc., are ab- 
sorbed directly into the blood through thin-walled blood-vessels. 
Water is certainly absorbed in the large intestine, and some di- 
gestion may go on in it, but mostly it acts as a channel and temporary 
receptacle for undigested matters, which are finally cast out. 
Questions for Review. 
What are the organs of digestion ? 
What is the alimentary or food canal ? 
How does it begin ? 
What is the gullet or oesophagus ? 
What are the parts of the alimentary canal in the abdomen ? 
What becomes of liquid food taken into the mouth ? 
What happens to solid or half-solid food in the mouth ? 
What glands are present in the mucous membrane of the mouth ? 
How many large glands pour their secretion into the mouth ? 
What is this secretion called ? 
What is the name of the largest of these glands ? 
Where is it situated ? 
What does the word parotid mean ? 
Where are the other two glands situated ? 
What peculiar property is possessed by saliva ? 
In what way is the turning of starch into sugar a useful process in 
digestion ? 
What becomes of food after it has undergone digestion in the 
mouth ? 
How is the food forced onward through the gullet or oesophagus ? 
What is the stomach ? Where is it situated ? 
What are present in the walls of the stomach ? 
What do the glands of the stomach secrete ? 146 
FIRST LESSONS IN PHYSIOLOGY. 
What takes place when the food reaches the stomach ? 
To what two things is the breaking up and dissolving of the food 
in the stomach due ? 
On what class of food-stuffs does the gastric juice act most rapidly 
and strongly ? 
What does the food become after undergoing the digestive proc- 
esses in the stomach ? 
How is food prevented from escaping from the stomach during di- 
gestion in the stomach ? 
What is the ring or valve at the outlet of the stomach called ? 
What glands are present in the walls of the small intestine ? 
What are the functions of the intestinal juice? 
What long, thin gland is situated behind the stomach ? 
What is secreted by the pancreas ? 
Into what is the pancreatic juice poured ? 
Upon what does the pancreatic juice act most strongly ? 
Does the pancreatic juice act upon starch and upon nitrogenous 
food ? 
What is bile ? 
By what organ is bile secreted ? 
Into what part of the alimentary canal is bile poured ? 
Upon what does the bile particularly act? 
Give an illustration to show the action of bile and pancreatic juice 
upon fats and oils. 
What is chyle ? 
From what is the word chyle derived ? 
What is absorption ? 
By what two sets of vessels is it chiefly performed? 
With what is the lining-coat of the small intestine covered ? 
What are the lacteals ? What is their function ? 
What is the thoracic duct ? 
Of what system of vessels are the lacteals a part ? 
How do they usually run ? What do they carry ? 
What is the function of the lymphatics ? 
Into what do the lymphatics empty ? 
What are found along the course of the lymphatics ? 
Name some substance absorbed directly into the blood. 
What are the functions of the large intestine ? CHAPTER XIV 
BREATHING 
153. The Air we Breathe.—The air is composed 
chiefly of two gases, oxygen and nitrogen, elements 
which also enter largely into our food. Oxygen is the 
great life-supporter. An animal deprived of it would 
soon die. When a candle burns, the substances in it 
unite with the oxygen of the air, and thus its burning 
is supported. When a lighted candle is put under a 
jar containing air, it will burn for a while and then 
go out, because it has used up all the oxygen and 
left only nitrogen. Nitrogen is necessary to man, but 
not in the same way as oxygen. In the air it acts to 
dilute or weaken the oxygen. Pure oxygen would be 
too much of a good thing. A candle in pure oxygen 
burns very brightly, but it soon burns itself out; so 
life would soon burn out if we breathed pure oxygen. 
154. The Blood Needs Oxygen.—The blood must 
have oxygen, and it gets most of what it needs from 
the air we breathe. The blood in the arteries gen- 
erally is of a bright red hue. The pulmonary or 
lung arteries, however, which carry blood from the 148 
FIRST LESSONS IN PHYSIOLOGY. 
right side of the heart to the lungs, contain dark blue 
or purple blood. The bright redness is due to the 
oxygen present. If air is kept out of the lungs of a 
living animal—by compressing the windpipe, for in- 
stance—the blood in the arteries will lose its redness; 
it will become dark, like venous blood. The oxygen 
attaches itself in some way to the red corpuscles of 
the blood. It can actually be pumped out of arterial 
blood. 
Fig. 38.—The Larynx, Trachea, Bronchi, and Lnngs. 
155. The Chief Organs for Breathing.—The chief 
organs for breathing are the trachea or windpipe, BREATHING. 
149 
which includes the larynx or voice-box, and the lungs. 
The nose, mouth, and throat also act as 
and passage-ways for the air; and the diaphragm and 
certain muscles of the chest help in the act of breath- 
ing. 
156. The Part Played by the Nose in Breathing. 
—The part played by the nose in breathing is by no 
means unimportant. The external air is first drawn 
through the nostrils. Inside the nose are thin plates 
of bones coiled upon themselves and covered with 
mucous membrane containing many blood-vessels. 
These are really “ warming plates,” like the plates of 
a stove.* The air passing over them is warmed before 
going to the lungs. Air should not be breathed in 
through the mouth, because it does not contain these 
“warming plates.” Colds are sometimes caught by 
taking cold air into the chest through the mouth. 
157. The Windpipe.—In the front of the neck is 
the trachea or windpipe, the large tube or pipe by 
means of which the air gets down into the lungs. It 
is firm and hard and made up of a number of rings 
of gristle placed one above the other. Behind it is 
the food-pipe or oesophagus. By running the fingers 
along the front of the neck, the rough windpipe can 
be felt through the skin. 
158. The Voice-Box.—The windpipe widens out 
at its upper part to form a sort of box, which opens 
above into the throat. This box is called the larynx, 
a harsh-sounding word, which is derived from a Greek 
* Fothergill’s “Animal Physiology for Schools.” 150 
FIRST LESSONS IN PHYSIOLOGY. 
word meaning “to shout.” The hard swelling seen 
on the outside of the upper portion of the neck, es- 
pecially in thin people, and sometimes called “Adam’s 
apple,” is produced by the bulging outwards of the 
larynx. Mucous membrane, vessels, nerves, muscles, 
ligaments, and cartilage all go to make up this won- 
derful little box in which the voice is formed. Ves- 
sels supply it with blood; nerves serve to regulate its 
actions, and the muscles and ligaments are the agents 
for moving it and holding it together. Several carti- 
lages, or pieces of gristle, are so arranged as to give 
the larynx a peculiar shape and fit it better to be a 
good voice-box. 
159. The Vocal Chords.—Voice is made in the 
larynx with the help of the vocal chords. These 
“chords,” as they are called, are not free bands or strings 
running across the cavity of the larynx. They are rather 
elastic lips or cushions fixed to the sides of the larynx, 
and having sharp free edges, between which is a 
narrow chink, the glottis, a Greek term which means 
the “mouth-piece of a flute.” In ordinary breathing, 
a current of air passing through this chink produces 
no sound. When air is forced out of the lungs in 
voice-making, however, the vocal chords become tight, 
and are drawn in and made to shake or vibrate. This 
shaking or vibration makes the sound of the voice, 
just as sound comes from the tight fiddle-string when 
the bow sets it to vibrating. Speech is more than 
voice. It is the voice changed into sounds which 
have a meaning by the action of the throat, palate, 
tongue, teeth, and lips. BREA THING. 
151 
160. The Lid of the Larynx.—A little lid of 
gristle or cartilage is placed over the top of the larynx. 
It is just behind the tongue at the lower and front part 
of the throat. When it is down, it covers the glottis 
or chink between the vocal chords. It is called the 
epiglottis, from epi, which means “ upon.” When we 
breathe, this little lid lifts up; but when we swallow, 
it drops, and thus food or drink is prevented from 
getting into the voice-box and windpipe. Occasionally, 
especially if we talk or laugh at the same time that we 
are swallowing, the epiglottis does not shut down 
quickly enough, and food goes down the wrong way, 
causing us to cough or choke. Life has been lost in 
this way. 
161. Bronchial Tubes and Air-Cells.—At the 
bottom of the windpipe, tubes or pipes branch to each 
side; from these others of smaller size proceed, and 
from the latter others still 
smaller. These are the 
bronchi or bronchial tubes. 
We have already spoken of 
the trachea as the windpipe; 
in the Greek, however, bron- 
chus means “windpipe,” and 
bronchus is an old term, 
now not often used, for the 
trachea or windpipe. The 
bronchi, then, are smaller 
windpipes, branches of the large windpipe. Some of 
the final bronchi are very small, but they are all hol- 
low, just as much as are the trachea and large bronchi, 
Fig. 39—Air-Cells Magnified. 152 
FIRST LESSONS IN PHYSIOLOGY. 
into which sticks might be thrust. Away out at the 
ends of the very finest bronchial tubes are little round 
bladders called air-cells. The lungs are made up 
largely of millions of these air-cells and fine bronchial 
tubes. 
162. Inspiration and Expiration.—Air drawn in 
through the nose or mouth, or both, passes into the 
larynx and windpipe, and then into the bronchi and air- 
cells. This drawing of air into the lungs is inspira- 
tion. After it has done its part, the air is driven out 
again from the air-cells through bronchi, windpipe, 
larynx, throat, and mouth or nose, this being expira- 
tion. The whole process of breathing, including both 
inspiration and expiration, is called respiration. In 
the case of an adult in good health, this breathing in 
and breathing out takes place about seventeen or 
eighteen times every minute. 
163. The Lungs and the Chest.—The lungs are 
within the cavity called the chest or thorax. It is 
an air-tight chamber. The diaphragm is its lower 
boundary. It has the sternum or breast-bone in its 
front and the back-bone or spine behind; and from 
back-bone to breast-bone run around the ribs. They 
are firmly attached to the breast-bone by gristle, but 
each rib is connected with the back-bone by a joint, 
which allows a little motion. Between the ribs are 
muscles; and when these muscles contract they pull 
up the ribs and cause the breast-bone to bulge forward, 
and thus more room is made for the lungs during in- 
spiration. 
164. The Diaphragm.—Between the chest and the BREA THING. 
153 
abdomen is the strong muscular partition, the dia- 
phragm. The lungs come plump down upon this 
diaphragm. When they are empty, or nearly so, that 
is, just after expiration, this diaphragm arches upward, 
following them as they shrink. When air is drawn 
into the lungs, the air-cells everywhere fill out; room 
must be made; the diaphragm moves downwards 
before the swelling air-cells. The organs below the 
diaphragm—the liver, stomach, spleen, intestines, and 
kidneys—are also pushed downwards. The diaphragm 
being a muscle, its fibres contract during in-breathing, 
causing it, as a whole, to flatten and descend. When 
next air is breathed out, it is relaxed and at rest, and 
it is drawn up by the lungs, to which it closely clings. 
165. Stationary Air and Tidal Air.—The lungs 
are not entirely emptied at each expiration or entirely 
filled at each inspiration. A certain amount of air, 
called stationary air, always remains in the air-cells 
of the lungs. Fresh air, or tidal air as it is called, is 
breathed in through the windpipe and bronchi, and 
this mixes with the stationary air of the air-cells and 
makes it purer. Breathing out or expiration then 
takes place, and some of the impure stationary air 
mixed with tidal air is driven out. 
166. How the Oxygen of the Air gets into the 
Blood.—Around the millions of air-cells of the 
lungs is a network of millions of capillary blood- 
vessels. Pumped by the heart, the dark venous 
blood gathered from all parts of the body, rushes 
through the lung arteries into these little vessels. This 
purple blood is loaded with poisonous carbonic acid 154 
FIRST LESSONS IN PHYSIOLOGY. 
gas, which leaks through the very thin walls of the 
blood-vessels and air-cells and mingles with the air, 
and is breathed out. At the same time oxygen from 
the air that has just been drawn into the lungs finds 
its way through cell-walls and vessel-walls into the 
blood. The blood gains oxygen and loses carbonic 
acid; the air gains carbonic acid and loses oxygen. 
167. Oxidation.—In candles, lamps, and burning 
or combustible substances in general, are elements 
called carbon and hydrogen. The oxygen which is 
in the air unites with the carbon or hydrogen of the 
burning body, and this process is called oxidation. 
Heat is given out when bodies burn ; a student’s lamp, 
or even a candle, will give out a very perceptible 
amount of heat. One of the results of oxidation is 
the production of warmth or heat. Oxidation is con- 
stantly going on in the body. In the food which we 
eat are the same elements which are in the fuel burned 
in the stove or furnace, or in the candle, or the oil of 
the lamp. We breathe in the oxygen of the air. 
This oxygen gets into the blood and unites with the 
elements of food, which have also found their way 
into the blood. The food is oxidized. In this way 
animal heat is produced and life is sustained. Breath- 
ing is one of the chief means of keeping the body 
warm. Much of physiology relates to this subject of 
oxidation. Oxygen is breathed in by the lungs and 
filters into the blood; it is carried hither and thither 
by the blood; it unites in the blood or tissues with the 
elements of the food. Oxidation is going on when we 
move, feel, will, think, or carry out any other function. SYLLABUS. 
155 
Syllabus. 
The air we breath is composed chiefly of oxygen and nitrogen, 
elements which also enter into onr food. 
Oxygen is the great life-snpporter. Nitrogen acts to dilute or 
weaken the oxygen. Pure Oxygen is too strong, and life would soon 
be burned out if we breathed it in the pure state. 
The blood needs oxygen, and it gets most of what it needs from 
the air. 
The bright red hue of arterial blood is due to the oxygen in it. 
The oxygen attaches itself in some way to the red corpuscles of the 
blood. 
The chief organs for breathing are the trachea or windpipe, which 
includes the larynx or voice-box, and the lungs. 
Inside the nose are thin plates of bones coiled upon themselves, 
and covered with mucous membrane containing many blood-vessels. 
These are really “ warming-plates.” The air passing over them is 
warmed before going to the lungs. 
Colds are caught by taking cold air into the chest through the 
mouth. 
In the front of the neck is the trachea or windpipe, a large tube 
firm and hard, and made up of a number of rings of gristle placed 
one above the other. This is the tube or pipe by means of which the 
air gets down the lungs. 
The windpipe widens out at its upper part to form the voice-box 
or larynx. 
Several cartilages are so arranged as to give the larynx a peculiar 
shape, and fit it better to be a good voice-box. 
Voice is made in the larynx with the help of the vocal chords, 
which are elastic lips or cushions fixed to the sides of the larynx, and 
having sharp, free edges, between which is a narrow chink, the glottis. 
When air is forced out of the lungs in voice-making, the vocal 
chords become tight, and are drawn in and made to shake or vibrate. 
Speech is voice changed into sounds which have a meaning by the 
action of the throat, palate, tongue, teeth, and lips. 
A little lid of gristle or cartilage, called the epiglottis, is placed 
over the top of the larynx. 
When we breathe, this little lid lifts up; but when we swallowi 
it drops, and thus food or drink is prevented from getting into the 
voice-box and windpipe. 156 
FIRST LESSONS IN PHYSIOLOGY. 
Bronchi or bronchial tubes branch off from the trachea or wind- 
pipe. 
Some of the final bronchi are very small, but they are all hollow. 
Away out at the ends of the very finest bronchial tubes are little 
round bladders called air-cells. The lungs are made up largely of 
millions of these air-cells and bronchial tubes. 
The drawing of air into the lungs is inspiration ; driving it out 
again is expiration ; the whole process of breathing is respiration. 
An adult in good health breathes in and out about seventeen or 
eighteen times every minute. 
The lungs are within the cavity called the chest or thorax, which 
is an air-tight chamber. The diaphragm is its lower boundary; it 
has the breast-bone in front, the back-bone behind, and from back- 
bone to breast-bone run around the ribs. 
Between the ribs are muscles; and when these muscles contract, 
they pull up the ribs and cause the breast-bone to bulge forward, 
and thus more room is made for the lungs during inspiration. 
Between the chest and abdomen is the diaphragm, upon which 
the lungs rest. 
When the lungs are empty, or nearly so, the diaphragm arches up- 
wards ; when air is drawn into the lungs, the diaphragm moves 
downward before the swelling air-cells. 
A certain amount of air, called stationary air, always remains in 
the air-cells of the lungs. 
Fresh air, or tidal air, as it is called, is breathed in through the 
windpipe and bronchi, and this mixes with the stationary air and 
makes it purer. 
When expiration takes place, some of the impure stationary air 
mixed with tidal air is driven out. 
Pumped by the heart, the dark venous blood gathered from all 
parts of the body rushes through the lung arteries into the mill- 
ions of capillary blood-vessels that surround the air-cells of the 
lungs. 
This purple blood is loaded with carbonic acid gas, wrhich leaks 
through the very thin walls of the blood-vessels and air-cells, and 
mingles with the air and is breathed out. At the same time, oxygen 
from the air finds its way through cell-walls and vessel-walls into the 
blood. 
The blood gains oxygen and loses carbonic acid; the air gains car- 
bonic acid and loses oxygen. QUESTIONS FOR REVIEW. 
157 
The oxygen which is in the air, unites with the carbon or hydro- 
gen of burning bodies, and this process is called oxidation. 
One of the results of oxidation is the production of warmth or 
heat. 
Oxidation is constantly going on in the body. 
In the food which we eat are the same elements which are in the 
fuel burned in the stove or furnace, or in the candle, or in the oil of 
the lamp. 
The oxygen of the air gets into blood and unites with the elements 
of the food which have also found their way into the blood. 
The food is oxidized; and in this way animal heat is produced and 
life is sustained. 
Breathing is one of the chief means of keeping the body warm. 
Much of physiology relates to this subject of oxidation. 
Oxidation is going on when we move, feel, will, think, or carry out 
any other function. 
Questions for Review. 
Of what is the air composed ? 
Which constituent of the air is the great life-supporter ? 
How is the burning of a candle supported ? 
Why does a lighted candle put under a jar go out? 
How does the nitrogen act? 
Where does the blood get the oxygen which it needs ? 
What in general is the color of blood in the arteries ? 
What arteries alone contain dark blue or purple blood ? 
To what is the bright redness of arterial blood due ? 
How can the blood in arteries be made to turn dark ? 
To what in the blood is the oxygen attached? 
What are the chief organs for breathing ? 
What part is played by the nose in breathing ? 
What “warming plates” are found inside of the nose? 
Why should air be breathed into the mouth ? 
How are colds often caught ? 
Where and what is the trachea or windpipe ? 
What is the larynx? Describe its structure. 
How is the voice made in the larynx ? 158 
FIRST LESSONS IN PHYSIOLOGY. 
What are the vocal chords ? 
What is the glottis ? 
What happens to the vocal chords in voice-making ? 
What is placed over the top of the larynx ? 
What is the lid of the larynx called, and why ? 
What happens to the epiglottis when we breathe ? 
What occurs when we swallow ? 
What accidents sometimes happen from talking or laughing at the 
same time that we are swallowing ? 
What are the bronchial tubes ? 
What is the meaning of the word bronchus ? 
What are found away out at the ends of the very finest bronchial 
tubes ? 
Of what are the lungs largely composed ? 
What is the process of inspiration ? 
What is expiration ? 
What is the whole process of breathing called ? 
How often does breathing in and breathing out take place in a 
healthy adult? 
Describe the chest or thorax. 
What is the action of the muscles situated between the ribs ? 
What is the diaphragm ? 
How are the lungs placed with reference to the diaphragm just 
after expiration ? 
What happens to the diaphragm when air is drawn into the lungs, 
and the air-cells everywhere expanded ? 
Are the lungs entirely emptied at each expiration ? 
Are the lungs entirely filled at each inspiration ? 
What is the air that always remains in the air-cells called ? 
What is the air breathed in at each inspiration called ? 
What net-work surrounds the air-cells of the lungs ? 
Describe the manner in which the venous blood gets into the capil- 
laries of the lungs. 
With what is the purple venous blood loaded? 
What becomes of the carbonic acid gas ? 
At the same time that carbonic acid leaves, how does oxygen enter 
the lungs ? 
What does the blood gain ? What does it lose ? 
What does the air gain ? What does it lose ? 
What elements are found in burning or combustible substances ? QUESTIONS FOR REVIEW. 
159 
What is oxidation ? 
What is given out when bodies burn ? 
What is one of the results of oxidation ? 
What is constantly going on in the body ? 
What elements are found in the food which we eat ? 
How is animal heat produced ? 
What is one of the chief means of keeping the body warm ? 
To what subject does much of physiology relate ? CHAPTER XV, 
THE AIR AND HEALTH 
168. Pure Air and Its Relation to Health.— 
Pure air is essential to health; the blood calls for enough 
of it to give a full supply of oxygen. In the last 
Chapter, we learned that the lungs were never entirely 
emptied at expiration, nor filled at inspiration, but that 
a certain amount of stationary air always remained. 
This stationary air in the lungs needs to be constantly 
changed and renewed by fresh or tidal air, that it may 
be kept pure. The stationary air has been estimated 
at two hundred and fifty cubic inches; and the tidal 
air, which comes in at each breath, at twenty-six 
cubic inches. The tidal air is, therefore, continually 
renewing and purifying the stationary air. Sickness, 
and other evils, result from an imperfect supply of 
pure air, or from a supply of impure air, to the lungs. 
169. How the Air is kept Pure in Nature.— 
The open air is kept pure and wholesome by certain 
natural processes. It is washed by the dew and rain. 
The sun warms and dries it. Its supply of oxygen 
and carbonic acid is largely regulated by the vegetable 
world—by the gardens, fields, and forests. Oxygen is THE AIR AND HEALTH. 
161 
given out by plants; carbonic acid is absorbed by them. 
Animals, on the other hand, give out carbonic acid, 
and absorb oxygen; and thus a proper balance is pre- 
served. All gases have a tendency to spread or diffuse 
themselves in all directions; so that carbonic acid, 
oxygen, or nitrogen, will not collect in one place. This 
diffusive power helps to keep the air pure. The winds 
increase the diffusion. 
170. How the Air may be Rendered Unwhole- 
some.—The air may be rendered impure and unwhole- 
some in various ways. The total amount of air 
supplied to a given space may be too small. Some of 
the ingredients of the air may be wanting or in excess. 
We have learned that the air is chiefly composed of 
oxygen and nitrogen; but, besides these, pure air also 
contains a nearly fixed amount of carbonic acid, and 
a variable amount of watery vapor. As the amount 
of carbonic acid may be influenced by many special 
causes, variations in the quantity of this gas often 
render the atmosphere impure. The temperature of 
the air may be too high or too low. The air may 
contain too much or too little moisture or watery 
vapor. Sometimes impurity in the form of dust, often 
unseen, is in the air. It is supposed that the dust of 
our rooms frequently contains the germs of disease. 
Exhalations from decaying animal or vegetable mat- 
ters sometimes poison the air. The air of our houses, 
particularly of our city houses, is not infrequently 
rendered impure by sewer-gas, which escapes from the 
drain-pipes which are intended to carry off waste and 
foul matters. 162 
FIRST LESSONS IN PHYSIOLOGY. 
171. Amount of Fresh Air Required for Health. 
—An individual should be supplied with two thousand 
cubic feet of fresh air per hour. It has been calculated 
that every man ought to have at least eight hundred 
cubic feet of space to himself, and that the atmosphere 
ought to have free access directly or indirectly to that 
space. A cubical room, a little more than nine feet in 
each of its dimensions, would give this amount of 
space. A little thought will show us how seldom this 
requirement is met in our homes, school-rooms, and 
public halls. 
172. Air Spoiled by One Man’s Breath.*—A 
man, by his breath, will spoil in twenty-four hours 
about three hundred and fifty cubic feet of air; as 
much, that is, as would be contained in a room a 
little more than, seven feet square, with a ceiling- 
seven feet high. Could all the carbonic acid exhaled 
by a man in that number of hours be collected, and its 
carbon extracted from it, the latter would be equal to 
half a pound or more of charcoal, besides the organic 
matter given off, whose amount is not easily estimated. 
173. Excess of Carbonic Acid in the Air.—Some- 
times the air contains too much carbonic acid. This 
poisonous gas is constantly being given off by the 
lungs in breathing. Decaying animal and vegetable 
matter and burning bodies also produce it. Too 
* Our Homes, by Henry Hartshorne, A.M., M.D. One of the series 
of American Health Primers edited by W. W. Keen, M.D., and 
published by Presley Blakiston, Philadelphia, 1880. Many valuable 
facts and ideas with reference to the air and ventilation have been 
obtained from this book. THE AIR AND HEALTH. 
163 
many people should not be gathered together in a 
small or badly aired room, or carbonic acid will collect 
in large amounts, and cause depression and languor. 
In mines, carbonic acid, and other poisonous gases, 
sometimes form, which injure or cause the death of 
the miners. 
174. Deadly Effects of Carbonic Acid.—Many 
striking illustrations might be given of the deadly 
effects of an excess of carbonic acid in the air. In 
Italy is a cave or grotto through which a man may 
pass without danger, but a dog on entering it is in- 
stantly suffocated. Carbonic acid gas is here con- 
stantly issuing from the earth, and, on account of its 
weight, accumulates at the bottom of the cavern, 
while the air above is comparatively pure. In the 
Island of Java is a “Valley of Poison,” where the 
ground is covered with the skeletons of birds and 
animals which have been suffocated by carbonic acid, 
which is present in large quantities. In Italy, also, is 
the Lake of Avernus, surrounded on every side but 
one by steep and densely wooded hills. The word 
“Avernus” is derived from Greek words meaning 
“ without birds.” According to the story, birds fly- 
ing over the lake are poisoned by carbonic acid, and 
fall dead into the water. The ancients believed that 
this lake was the entrance to the infernal regions. 
Carbonic acid gas is sometimes used to suffocate 
butterflies and other insects when it is desired to pre- 
serve their colors perfect. In some of our large cities 
it is used to kill the dogs at the pounds, death by this 
method being painless, 164 
FIRST LESSONS IN PHYSIOLOGY. 
175. Terrible Results of Crowding.—When hu- 
man beings are crowded together, they breathe not 
only the carbonic acid and impure matters exhaled by 
others, but also rebreathe their own impure exhala- 
tions. The blood is poisoned, and the effects are 
sometimes terrible. The story of the “ Black Hole of 
Calcutta ” is often told to illustrate this fact. During 
a war in India, in the hot month of June, 1756, one 
hundred and forty-six Englishmen were shut up in a 
little room which contained only two very narrow 
windows. In eight hours all but twenty-three died. 
A steamer was overtaken at sea by a storm; the cap- 
tain ordered all the passengers below, and then fas- 
tened down the hatches to prevent the water from 
getting into the vessel. In six hours, seventy-two 
died of suffocation. 
176. Diseases of the Lungs and Air-Passages.— 
That common form of indisposition or sickness called 
a “ cold,” is sometimes caught by breathing through 
the mouth instead of the nose. Cold air is thus taken 
directly into the lungs instead of being tempered by 
the “ warming-plates ” in the nose. Colds are taken 
in many other ways, however; as, by exposure, par- 
ticularly when heated, to draughts of air; by remain- 
ing too long in wet clothes; or by an insufficient or 
excessive amount of clothing. Croup, an affection of 
the larynx and windpipe ; bronchitis, an inflammation 
of the mucous membrane which lines the bronchial 
tubes ; and pneumonia, or inflammation of the lungs, 
are some of the diseases which result from improper 
exposure to cold and dampness. Consumption, or SYLLABUS. 
165 
phthisis, that much dreaded chronic disease, which 
causes destruction of the lungs, is often induced by 
impure air. A life in the open air, with plenty of 
good food and sufficient exercise, are among the best 
means of warding off or treating this disease. 
177. Clothing with Reference to the Lungs and 
Breathing.—Clothing should be so worn as to allow 
the lungs and chest full chance to expand, or sufficient 
air will not enter the lungs to purify the blood. In 
children especially, while the bones are soft and yield- 
ing, the clothing should not be too tight. The bony 
frame-work of the chest is by nature somewhat wider 
below than above. Tight-lacing turns this natural 
state of things around, causing deformity. 
Syllabus. 
Pure air is essential to health, because the blood calls for a full sup- 
ply of oxygen. 
Fresh or tidal air is continually renewing and purifying the sta- 
tionary air. 
The open air is kept pure and wholesome by certain natural pro- 
cesses. It is washed by the dew and rain; it is warmed and dried 
by the sun; the vegetable and animal world help to preserve the 
proper balance between oxygen and carbonic acid ; and gases having 
a tendency to spread or diffuse themselves, too much of one gas will 
not collect in one place. 
The total amount of air supplied to a given space may be too small, 
or some of its ingredients may be wanting or in excess. 
Variations in the quantity of carbonic acid gas often render it im- 
pure. 
The temperature of the air may be too high or too low. 
The air may contain too much or too little moisture. 166 
FIRST LESSONS IN PHYSIOLOGY. 
Dust, exhalations from decaying animal or vegetable matters, and 
sewer-gases, are other sources of impurity of the air. 
An individual should be supplied with two thousand cubic feet of 
fresh air per hour. He ought to have at least eight hundred cubic 
feet of space to himself, and the atmosphere ought to have free access 
to this space. 
In twenty-four hours, a man will spoil by his breath about three 
hundred and fifty cubic feet of air. 
Sometimes the air contains too much carbonic acid. 
Carbonic acid gas is constantly given off by the lungs in breath- 
ing ; and decaying animal and vegetable matter and burning bodies 
also produce it. 
In a small or badly-aired room, carbonic acid will collect in large 
amounts and cause depression and languor. In mines, it and other 
poisonous gases sometimes form. 
When human beings are crowded together, they breathe not only 
the carbonic acid and impure matters exhaled by others, but also 
re-breathe their own impure exhalations. 
A “cold” is sometimes caught by breathing through the mouth 
instead of the nose. Cold air is thus taken directly into the lungs, 
instead of being tempered by the “warming-plates” in the nose. 
Colds are also taken by exposure to draughts of air, by remaining 
too long in wet clothes, or by an insufficient or excessive amount of 
clothing. 
Croup, bronchitis, and pneumonia are some of the diseases which 
result from improper exposure to cold and dampness. 
Consumption, or phthisis, is often induced by impure air. Life in 
the open air, with plenty of good food and sufficient exercise, are the 
best means of preventing or treating this disease. 
Clothing should be so worn as to allow the lungs and chest full 
chance to expand. 
Tight-lacing is injurious. 
Questions for Review. 
Wliy is pure air essential to health ? 
Why does the stationary air in the lungs need to be constantly 
changed and renewed? 
To how much does this stationary air amount ? QUESTIONS FOR REVIEW. 
167 
How much tidal air comes in at each breath ? 
What result from an imperfect supply of pure air ? 
How is the open air kept pure and wholesome ? 
By what is it washed? What warms and dries it? 
How is its supply of oxygen and carbonic acid largely regulated ? 
What is given out by plants ? What is absorbed by them ? 
What is given out by animals ? What is absorbed by them ? 
What tendency have all gases ? 
What does the diffusive power of gases help to do ? 
How do the winds act ? 
Mention some of the methods by which the air may be rendered 
impure and unwholesome. 
What is said of carbonic acid rendering the air impure ? 
What is said of temperature, moisture, dust, organic exhalations, 
and sewer-gas ? 
How much fresh air per hour should be supplied to an individual ? 
How many cubic feet of space should he have to himself? 
How many cubic feet of air will a man spoil by his breath in 
twenty-four hours ? 
How much carbon could be extracted from the carbonic acid ex- 
haled by a man in twenty-four hours ? 
Mention some of the ways in which an excess of carbonic acid 
originates. 
Give some illustrations of the deadly effects of an excess of carbonic 
acid in the air. 
Give some illustrations of the terrible results of crowding. 
How are colds sometimes caught ? 
Name some diseases of the air-passages and lungs which result 
from improper exposure to cold and dampness. 
How is consumption often induced ? 
What are among the best means of preventing or treating this 
disease ? 
How should clothing be worn ? 
What is said about tight-lacing ? CHAPTER XVI. 
VENTILATION. 
178. Ventilation.—The word ventilation is derived 
from the Latin, ventus, “ air ” or “ wind.” To “ venti- 
late” a place literally is to “cause the air to pass 
through it.” Ventilation is the process by which the 
air to be breathed is kept pure. The buildings in 
which we live, and the lungs with which we breathe, 
should always be kept well ventilated. The tidal air 
ventilates the stationary air of the lungs. When we 
speak of ventilation, however, we generally have ref- 
erence to the processes employed to keep our houses, 
churches, school-rooms, and public halls supplied with 
pure air. 
179. Objects to be Aimed at in Ventilation.— 
The objects to be aimed at in ventilation are: 1. To 
move uniformly through a building the required 
amount of pure, fresh air. 2. Duly to distribute this 
air to the different apartments in the house. 3. Prop- 
erly to diffuse it in each .room. 4. To remove the 
vitiated air from every room in the building. 5. To VENT TLA TION. 
169 
warm the air sufficiently in winter. 6. To supply it 
with an appropriate amount of moisture.** 
180. Natural Ventilation.—The term natural or 
accidental ventilation is applied to that ventilation 
which is brought about by the ordinary construction 
of our dwelling-houses and public buildings—chiefly 
by doors, windows, and open fireplaces. Doors and 
windows which can be opened and shut at pleasure 
answer very well in some seasons and climates. Open 
fireplaces, when constructed properly, are efficient 
aids to ventilation. A fireplace with a wide-throated 
chimney, and either a coal-grate or a wood-fire burn- 
ing in it, seldom needs any inlets or outlets for venti- 
lation besides the cracks which unintentionally exist 
in windows and doorways. 
181. The Walls of Buildings Permeable to Air. 
—Natural ventilation is accomplished in part by the 
walls of our buildings, through which more or less air 
will find its way. Brick, sandstone, and mortar can 
be penetrated by the air. The air which passes 
through walls may not be felt, because currents of air 
moving at a rate less than about twenty inches a second 
are not sensibly perceived. A scientist, named Petten- 
kofer, devised a curious experiment to show how air 
penetrates through gravel. He half filled a glass 
cylinder with gravel, over which a wire netting was 
placed; in this a canary bird was put, over him another 
wire netting, and above that the cylinder was filled to 
the top with gravel. The bird lived all day without 
* The facts in this and several succeeding paragraphs have been 
chiefly obtained from Dr. Hartshorne’s book. 170 
FIRST LESSONS IN PHYSIOLOGY. 
seeming to be incommoded for want of air. The 
warmth of its body induced a gentle ascending and 
descending current of air around it through the two 
layers of gravel, the upper one communicating with 
the atmosphere. Without such a movement to renew 
the air for it to breathe, it would have been fatally 
poisoned in a very few hours. 
182. Artificial Ventilation.—Artificial ventilation 
is that winch is afforded by special apparatus or arrange- 
ments. To admit pure air to a room, one of the sim- 
plest plans is the insertion of a piece of wood made to 
fit under the lower sash of a window raised a few 
inches. Air then enters upwards between the two 
sashes at their place of junction. Another arrange- 
ment * is to place a piece of cloth or paper on the 
lower ten or twelve inches of the window-frame, and 
then raise the lower sash more or less, according to the 
weather. To get an upward-directed draught, a good 
method is to fix an upward-sloping board about six 
or eight inches below the top of a window, and then 
let down the upper sash a few inches. To allow air 
to come in slowly and without draught, another 
plan is to remove a pane from a window, and in its 
place to introduce wire gauze, or a piece of zinc per- 
forated with a number of small holes. An ingenious, 
but not complicated, apparatus is that known as 
Maine’s elbow-tube ventilator, which consists of a 
board (made in two parts sliding on each other, so as 
to be adjusted to different windows) to be placed under 
a raised sash, but having passed through it two pipes 
* Suggested by Dr. W. W. Keen, of Philadelphia. VENTILATION. 
171 
or tubes, about six inches in diameter, each bent up- 
ward in an elbow'—the top of each tube being open 
above, and supplied with a regulating valve. 
183. Relation of Inlets to Outlets in Ventilating. 
—To ventilate a room thoroughly, it is necessary to 
have outlets as well as inlets for the air. For rooms 
warmed by heated air, various arrangements for allow- 
ing air to enter and pass out have been invented. 
Generally, warm air enters near or in the floor, and 
escapes above near or in the ceiling. The outlet may 
be situated at various points with reference to the 
inlet—sometimes directly above, sometimes on the 
opposite side of the room, sometimes in the middle of 
the ceiling, the inlet being at one end or side. One 
good plan for small rooms is to have a warm-air regis- 
ter near the floor on one side, and a ventilating outlet 
near the ceiling on the other side ; another is to have 
tw'O registers, one on each side of a room, the outlet 
being in the ceiling. In the northwestern part of 
Philadelphia several blocks of houses have been built 
with an improved arrangement for ventilation. Each 
house has an air-chamber between the roof and upper 
floor. Narrow openings for air are placed in the 
walls at the sides of this chamber; and a ventilator 
is placed between it and the room below. The outlet 
to the chamber is a ventilating-pipe in the roof. 
184. Temperature of the Air in Living Rooms. 
—For a school-room or sitting-room a temperature of 
about 68° to 70° Fahrenheit is the best in our climate. 
For a workshop, gymnasium, or any room in which 
active exercise is being taken, a lower temperature 172 
FIRST LESSONS IN PHYSIOLOGY. 
will be better. For a sick-chamber, a temperature 
above 70° may sometimes be desirable. Over-heated 
or unequally-heated rooms are injurious to health. 
185. Moisture of the Air in Living-Rooms.— 
The air of a living room, to be healthy, should always 
contain a certain amount of moisture. Stoves and 
furnaces sometimes cause undue dryness of the atmos- 
phere. The proportion of moisture or aqueous vapor 
in the atmosphere may vary greatly. The possible 
amount present depends largely on the temperature. 
The higher air is heated the more watery vapor it is 
able to contain. When the rooms of a house are kept 
at a high temperature by means of heated air, some 
special arrangements should be made to evaporate 
water in them. A shallow pan of water placed over 
a stove or near a register will answer. Many heaters 
are supplied with an evaporating pan, by means of 
which moisture is supposed to be supplied to a whole 
house; but this alone will not do, as different apart- 
ments may be heated unequally, and the degree of 
humidity, as just stated, varies with the tempera- 
ture. 
186. The Ventilation of School-Rooms and 
Public Buildings.— School-rooms, where growing 
children spend so many hours at their tasks, should 
be thoroughly ventilated. The mind cannot be bright 
when the air is impure. Good authority asserts that 
from one to two thousand cubic feet of pure air should 
be supplied hourly to every child confined in school, 
in order that perfect health may be sustained. Very 
much less than this is usually furnished. Too often SYLLABUS. 
173 
little or no attention is paid to ventilation; pupils 
become listless and stupid; and their health is under- 
mined. Our churches, theatres, and public halls are 
equally neglected. 
187. The Ventilation of Bedrooms.—Fresh air 
should not be excluded from bedrooms. Some people, 
believing night-air to be unhealthy, keep the rooms 
in which they sleep as close as possible; they try to 
shut out every breath of air as if it were poison. Un- 
less a house is very loosely built, it is better, as a rule, 
to open the windows of a sleeping-room a little, even 
in cold weather; although most people cannot stand 
to have a draught of air blowing directly upon them 
while asleep. The old fashion of surrounding a bed 
with curtains, or putting it in a curtained recess, was 
a very bad one, but fortunately is now but little in 
vogue. The sleeper was thus compelled to breathe 
over and over again his own poisonous breath. 
Syllabus. 
Ventilation is the process by which the air to be breathed is kept 
pure. 
The tidal air ventilates the stationary air of the lungs. 
When we speak of ventilation, we generally have reference to the 
processes employed to keep our houses, churches, school-rooms, and 
public halls supplied with pure air. 
The objects to be aimed at in ventilation are: 1. To move uni- 
formly through a building the required amount of pure, fresh air, 
2. Duly to distribute the air to the different apartments in the house, 
3. Properly to diffuse it in each room. 4. To remove the vitiated air 
from every room in the building. 5. To warm the air sufficiently 174 
FIRST LESSONS IN PHYSIOLOGY. 
in winter. 6. To supply it with an appropriate amount of moist- 
ure. 
Natural or accidental ventilation is that brought about by the 
ordinary construction of our dwelling-houses and public buildings— 
chiefly by doors, windows, and open fireplaces. 
Natural ventilation is accomplished in part by the walls of our 
buildings, through which more or less air finds it way. 
Artificial ventilation is that which is afforded by special apparatus 
or arrangement. 
In ventilating a room warmed by heated air, generally warm 
air enters near or in the floor, and escapes above near or in the 
ceiling. 
The outlet may be situated at various points with reference to the 
inlet—directly above, on the opposite side of the room, in the middle 
of the ceiling, the inlet being at one end or side. 
One good plan for small rooms is to have a warm-air register near 
the floor on one side, and a ventilating outlet near the ceiling on the 
other side. Another is to have two registers, one on each side of a 
room, the outlet being in the ceiling. 
For a school-room or sitting-room, a temperature of about 68° to 
70° F. is the best in our climate. 
For a workshop, gymnasium, or any room in which active exercise 
is being taken, a temperature lower than 68° will be better. 
For a sick-chamber, a temperature above 70° may sometimes be 
desirable. 
Over-heated or unequally-heated rooms are injurious to health. 
The air of a living-room, to be healthy, should always contain a 
certain amount of moisture. 
The higher air is heated, the more watery vapor it is able to 
contain. 
When the rooms of a house are kept at a high temperature by 
means of heated air, some special arrangements should be made to 
evaporate water in them. 
School-rooms, churches, theatres, and other public buildings, should 
always be thoroughly ventilated. 
Fresh air should not be excluded from bedrooms. It is better to 
open the windows of sleeping-rooms. 
Surrounding a bed with curtains, or putting it in a curtained re- 
cess, is a bad fashion, because the sleeper is thus compelled to breathe 
over and over again his own poisonous breath. QUESTIONS FOR REVIEW. 
175 
Questions for Review. 
From what is the word ventilation derived ? 
Define ventilation. 
By what is the stationary air of the lungs ventilated ? 
When we speak of ventilation, to what do we generally refer ? 
What six objects should be aimed at in ventilation? 
To what is the term natural or artificial ventilation applied ? 
How is natural ventilation usually accomplished ? 
What is said of doors, windows, and open fireplaces ? 
Does air penetrate the walls of our buildings ? 
At what rate must currents of air move in order to he sensibly 
perceived ? 
Describe an experiment to show how air penetrates through 
gravel. 
What is artificial ventilation ? 
Mention some of the best methods of admitting air into a room. 
Describe Maine’s elbow-tube ventilator. 
What is said of outlets for air ? 
In general, where does warm air enter, and where does it leave a 
room ? 
Mention some of the situations in which outlets may be placed 
with reference to inlets in ventilating. 
Describe an improved arrangement for ventilating some houses 
recently built in Philadelphia. 
What is the best temperature for a school-room or sitting-room ? 
What is the best temperature for a workshop or a gymnasium ? 
What temperature may sometimes be desirable for a sick-room ? 
What is said about moisture in the air of a living-room? 
What is sometimes the effect of stoves and furnaces ? 
Upon what does the possible amount of moisture in the atmosphere 
largely depend ? 
When the rooms of a house are kept at a high temperature, what 
should be done to insure a proper amount of moisture ? 
How many cubic feet of air should be supplied hourly to every 
child in school ? 
Is proper attention paid to ventilation of school-rooms and public 
buildings ? 
Mention some facts about the ventilation of bedrooms. CHAPTER XVII 
EXCRETION, OR GETTING RID OF WASTE 
MATTERS. 
188. Wear and Waste.—The body is wearing and 
wasting, as well as growing and repairing, all the 
time. We eat and drink a number of times each 
day, and, besides, we are constantly breathing in oxy- 
gen, which is a real food to the blood. Food, as we 
have learned, makes the blood rich, and the blood 
feeds the tissues—bone, muscle, nerve, glands, etc. 
The blood is constantly building these tissues. The 
parts of the body are, however, always at work, and 
everything that works must wear and waste, so that 
tissues are as constantly breaking down as they are 
building. Our bodies are always being made and 
unmade. It is a curious fact that the blood, which is 
the chief agent in building the tissues, also receives 
the products of their wasting. It takes up the useless 
particles, and carries them to the organs which cast 
them out of the body. 
189. Wasting Destruction are not the Same. 
—The different parts of the body waste through the EXCRETION. 
177 
process of oxidation, but they are not destroyed. 
They change into other forms. When a frame house 
burns, it disappears as a house and as wood, but in the 
smoke and in the ashes are the same elements which 
were in the wood at first, with the addition of the 
oxygen which was taken from the air during the 
burning. This is similar to what takes place in the 
body. Substances which the blood gets from the 
food are oxidized or burnt up; tissues also are oxi- 
dized ; but their elements are not destroyed. 
190. The Principal Waste-Products of the 
Body.—These waste-products of the body usually be- 
come in the blood either water, carbonic acid, or urea, 
with small quantities of certain salts. Water is com- 
posed of hydrogen and oxygen; carbonic acid, of car- 
bon and oxygen ; urea, of carbon, hydrogen, nitrogen, 
and oxygen; and most of the salts contain oxygen, 
metals, and such substances as sulphur and phosphorus. 
In our food and tissues we have carbon, hydrogen, 
nitrogen, oxygen, phosphorus, sulphur, etc. ; in the 
air is all-important oxygen. It is in great measure 
through the process of oxidation—through other sub- 
stances seizing oxygen or oxygen seizing them—that 
waste-products are formed. 
191. Waste Water.—Water is taken into the 
body, or is formed there in many ways. Much is 
taken in by drinking, much in our solid food. Oxy- 
gen seizes hydrogen in many places where tissues are 
breaking up into their elements, and thus also water 
is formed. 178 
FIRST LESSONS IN PHYSIOLOGY. 
192. Carbonic Acid.—The oxygen which is being 
constantly breathed in by the lungs goes, as we have 
learned, all through the body; the red corpuscles of 
the blood acting as oxygen-carriers. They carry the 
oxygen into the tissues, wherever it is needed. The 
tissues all contain carbon. In some way, not yet fully 
understood, this carbon unites with the oxygen; and 
carbonic acid gas is formed. The blood, if examined 
chemically, can be shown to contain this carbonic 
acid. 
193. Urea.—Urea is a substance in some respects 
like ammonia or hartshorn, but more complicated in 
composition. Many tissues, such as muscle and nerve, 
contain nitrogen in large amounts. Urea results 
largely from the wasting of these nitrogenous tis- 
sues ; but it is also partly derived from other tissues 
containing carbon and hydrogen. It also springs partly 
from the action of some of the fluids of the alimen- 
tary canal upon nitrogenous food. It is really pro- 
duced by a partial oxidation—the same process of 
oxidation which gives carbonic and water, only the 
process does not go far enough for carbonic acid and 
water to be formed. 
194. Excretion.—The process by which these waste- 
products of the body are taken from the blood and 
cast out of the system is called excretion, which means 
the “act of sifting out.” The waste-products them- 
selves are called excretions. Excretions differ from se- 
cretions, such as saliva, bile, gastric juice, and the like, 
in that the latter have a purpose to serve in the body, 
while the former are simply refuse and waste matters. EXCRETION: 
179 
Excretion is carried on chiefly by the skin, the lungs, 
and the kidneys. 
195. The Skin as an Organ of Excretion. In 
Chapter I. the skin was described as consisting of an 
outer very thin layer called the epidermis, and of an 
inner and thicker layer, the dermis, or true skin. 
Running through both epidermis and dermis is an open 
channel, the sweat-duct, which in the latter coils up 
into a knot. This knotted end of the tube is a sweat- 
gland, (Fig. 40.) It is surrounded by a 
mesh or network of thin-walled capillary 
blood-vessels. The sweat-glands, which 
are exceedingly numerous, excrete waste 
water from the system as sweat or perspi- 
ration. Some chemical salts, in very small 
quantity, are dissolved in the sweat or per- 
spiration, which passes off by the skin. We 
are really sweating more or less all the time. 
Physiologists speak of two kinds of per- 
spiration, sensible and insensible. Sensible 
perspiration is that which we can see and 
feel, the ordinary sweat; insensible perspi- 
ration is that which is going on without 
being seen. The reason it is not recog- 
nized is because it passes off as steam or 
vapor as soon as it is formed. 
Fig. 40. 
Vertical Sec- 
tion of the 
Skin. (Highly 
magnified.) 
196. The Lungs as Organs of Excretion.—The 
blood loaded with poisonous carbonic acid gas comes 
to the capillary vessels of the lungs. This gas finds 
its way through the thin walls of the vessels and air- 
cells and is breathed out. Much water also leaks 180 
FIRST LFSSONS IN PHYSIOLOGY. 
from the blood and is exhaled with the breath. Glass 
can be moistened by breathing on it. 
197. The Kidneys as Organs of Excretion.—The 
kidneys are two in number, and are situated in the 
lower back part of the abdominal cavity, one on each 
side of the spinal column. Each kidney is between 
four and five inches long and from two to three inches 
in breadth. Blood-vessels enter the kidneys. The 
blood brought to the kidneys contains some of the 
waste-products of the tissues, particularly the urea. 
These waste matters, in the form of a liquid, are 
secreted or filtered from the blood into little tubes 
in the kidneys. This liquid, which consists mainly 
of urea dissolved in a very large quantity of water, 
with, however, small quantities of other animal and 
mineral substances, is finally collected by the body, 
and then cast out of the body. 
198. Similarity of the Organs of Excretion.— 
The skin chiefly excretes water in the form of sweat, 
but small quantities of carbonic acid, and even of urea, 
are also passed off by it. The lungs are mainly con- 
cerned with casting out carbonic acid and water, but 
urea in small amount is also found in expired air. 
The kidneys have for their chief function the excre- 
tion of water and urea, but they also get rid of some 
carbonic acid. These three sets of organs, working 
together, prevent the machinery of the body from 
becoming clogged and choked with impurities. We 
should constantly aim to keep them in good working 
condition, in order that they may be able to carry out 
their functions. SYLLABUS. 
181 
Syllabus. 
The body is wearing and wasting, as well as growing and repairing, 
all the time. 
The parts of the body are always at work, and everything that 
works must wear and waste, so that the tissues are as constantly 
breaking down as they are building. 
The blood takes up the useless particles, the products of the wasting 
tissues, and carries them to the organs which cast them out of the body. 
Substances which the blood gets from the food are oxidized or burnt 
up ; tissues also are oxidized ; but their elements are not destroyed. 
The waste-products of the body usually become in the blood either 
water, carbonic acid, or urea, with small quantities of certain salts. 
Water is composed of hydrogen and oxygen; carbonic acid, of 
carbon and oxygen; urea, of carbon, hydrogen, nitrogen, and oxy- 
gen ; and most of the salts contain oxygen, metals, and such sub- 
stances as sulphur and phosphorus. In our food and tissues are 
these elements; in the air is oxygen. It is in great measure through 
other substances seizing oxygen or oxygen seizing them that waste- 
products are formed. 
Much water is taken into the body by drinking, much in our solid 
food. 
Oxygen seizes hydrogen in many places where tissues are breaking 
up into their elements, and thus also water is formed. 
The red corpuscles of the blood carry the oxygen wherever it is 
needed. The tissues all contain carbon. This carbon unites with the 
oxygen, and carbonic acid gas is formed. 
Urea results largely from the wasting of tissues which contain 
nitrogen in large amounts, such as muscle and nerve. 
It also springs partly from the action of some of the fluids of the 
alimentary canal upon nitrogenous food. 
Urea is really produced by a partial oxidation. 
Excretion is the process by which the waste-products of the body 
are taken from the blood and cast out of the system. It is carried on 
chiefly by the skin, the lungs, and the kidneys. 
Bunning through both the outer and inner layer of the skin is an 
open channel, the sweat-duct, which in the latter coils up into a knot, 
called the sweat-gland. 
The sweat-gland is surrounded by a network of thin-walled capil- 
lary blood-vessels. 182 
FIRST LESSONS IN PHYSIOLOGY. 
The sweat-glands, which are exceedingly numerous, excrete waste 
water from the system as sweat or perspiration. Some chemical salts, 
in very small quantity, are dissolved in the perspiration. 
Sensible perspiration is that which we can see and feel; insensible 
perspiration is that which is going on without being seen, is passing 
off as steam or vapor as soon as it is formed. 
Carbonic acid finds its way through the thin walls of the capillary 
vessels of the lungs into the air-cells, and is breathed out. Water 
also leaks from the blood and is exhaled with the breath. 
The blood brought to the kidneys contains some of the waste-pro- 
ducts of the tissues, particularly the urea; and these waste matters, 
in the form of a liquid, are finally cast out of the body. 
The skin chiefly excretes water in the form of sweat, but small 
quantities of carbonic acid, and even of urea, are also passed off by it. 
The lungs are mainly concerned with casting out carbonic acid and 
water, but urea in small amount is also found in expired air. 
The kidneys have for their chief function the excretion of water 
and urea, but they also get rid of some carbonic acid. 
The skin, the lungs, and the kidneys working together, prevent the 
machinery of the body from becoming clogged and choked with im- 
purities. 
Questions for Review. 
What is happening to the body all the time? 
What is the chief agent in building tissues? 
What receives the products of the wasting of the tissues ? 
What does the blood do with the useless particles ? 
Through what process do the different parts of the body waste ? 
What happens when a frame house burns ? 
What substances are oxidized? 
Are the tissues also oxidized? 
Are the elements of the food and of the tissues destroyed when 
oxidation takes place? 
What are the principal waste-products of the body? 
What is the composition of water, of carbonic acid, of urea, and 
of the salts? 
What elements enter into our food and tissues ? QUESTIONS FOR REVIEW. 
183 
What important element is in the air ? 
How is water taken into the body ? 
How is it formed-in the body ? 
Describe the process by which carbonic acid is formed in the body. 
What substance does urea resemble ? 
What tissues contain nitrogen in large amounts ? 
How is urea largely produced ? 
From what, also, does it partly spring ? 
What is the real nature of the process by which urea is produced ? 
Define excretion. 
What is the difference between excretions and secretions ? 
What are the organs of excretions ? 
What channel runs through the skin ? 
What is the knotted end of the sweat-duct called ? 
What do the sweat-glands excrete ? 
What is sensible perspiration ? 
What is insensible perspiration ? 
What excretions are cast out by the lungs ? 
Describe the kidneys. 
What waste matters are excreted by the kidneys ? 
Explain the similarity between the organs of excretion. 
What do the three sets of excretory organs accomplish ? CHAPTER XVIII. 
HINTS ON HYGIENE, ACCIDENTS, AND 
POISONS. 
199. Rules of Simple Hygiene.*—The following 
rules of simple hygiene will be found useful: 
Wash ‘the whole body, at least twice in every week, either with 
cold or slightly warmed water, and rub thoroughly dry with a 
rough towel. 
The least one can do, with any attention to cleanliness or health, 
is to sponge the face, chest, and back with water, and dry rub the 
rest of the body at least once every day. 
For a thorough wash of the hands, use warm water, and* before 
soaping them, steep them well in the water for a minute or'two, rub- 
bing them the while, then use soap and a nail-brush. End by hold- 
ing the hands under a tap of cold water, and “ give them a shower- 
bath : ” it is refreshing and strengthening to the fingers; or dip 
them into cold water and rub them dry as quickly as possible. 
* These “rules of simple hygiene” are from Hints and Remedies 
for the Treatment of Common Accidents and Diseases, and Rules of 
Simple Hygiene, compiled by Dawson W. Turner, D.C.L.: Macmillan 
& Co., New York. The rules are given with omissions, additions, and 
changes in language and arrangement. Dr. Turner’s book has been 
drawn upon for other material for the present chapter. We have also 
made use of a valuable little book by Dr. Charles W. Dulles, entitled 
What to do First in Accidents or Poisoning, published by Presley 
fllakiston, Philadelphia, 1880; and of a larger volume of Plain Di- 
rections for Accidents and Poisons, distributed by the Mutual Life 
Insurance Company of New York. HINTS ON HYGIENE. 
185 
If possible, get that most cleansing thing, a hot bath, once a 
week ; use plenty of soap, with a flannel, over the whole body, and 
scour with a pretty hard bath-brush ; then soak for a few minutes, 
and come out “ as clean as a new shilling.” 
Use a flesh-brush, or rough towel, on the skin once a day. The 
best time is at night. 
Brush the teeth the last thing every night before going to bed, 
and comb and brush the hair the wrong way, or any way but the 
right way, so as to let the air in upon the head. 
Rinse out the mouth, or, better still, brush the teeth after every 
meal. 
Tooth-brushes cannot be too soft. Hard brushes make the gums 
recede from the teeth, and produce premature decay by causing the 
soft bone of the tooth to be exposed to the air, beyond the part of 
the tooth protected by the enamel. 
Do not plaster down the hair with pomatum or pomade; the hair 
is meant to assist in carrying off perspiration, and should not be 
clogged with grease. Ho appreciable mischief results from oiling 
it occasionally ; nor does sweet-oil do any harm to any part of the 
body, if it is rubbed into the skin before a fire, but, on the contrary, 
it does good, as it renders the limbs supple and more capable of 
strong'muscular exertion. 
Beware of drinking any very hot fluids. After fatigue and long 
fasts, hot fluids, only not too hot, are valuable, and a few mouth- 
fuls, taken in such cases before beginning to eat, are useful, espe- 
cially for elderly people. 
Avoid much use of sweets, tarts, pastry, confectionery, and sugar. 
All clothing, particularly that which is worn next to the skin, 
should be turned inside out before going to bed, and hung up to air 
above the level of the head. 
Open the bed entirely in the morning, lifting the sheet and blan- 
ket so as to let the air get underneath ; and leave the windows open 
top and bottom. 
Never sit down to breakfast without first going out into the 
open air for a few minutes. Make the walk longer or shorter, 
according to health and strength. 
If any one is ill with fever, or with any infectious-disease, do not 
visit him the first thing in the morning before eating, but take a 186 
FIRST LESSON’S IN PHYSIOLOGY. 
mouthful of coffee or tea, and a crust of bread, before entering his 
bedroom. 
In order to avoid infection, or any low fever, look sharp after all 
drains and cesspools. Keep them in good repair and working 
order, and flush all sewers and drains now and then with plenty of 
water. In a dry season pour a pailful or two of water, with about 
a quarter of a pint of carbolic acid in it, into all drains and cess- 
pools every other day, to take away any bad smell. If carbolic 
acid cannot be had, use chloride of lime, or something of the same 
sort. Copperas (sulphate of iron) is a cheap but very efficient dis- 
infecting agent. A handful of this salt thrown down the water- 
closet three or four times a week answers every purpose. 
If troubled with cold feet at night, rub them well before getting 
into bed; and if that does not answer, sponge them with cold water, 
and, while drying them, rub the toes and ankles upwards, and not 
doAvnwards. In case this plan fails, as it does sometimes, and the 
feet still remain cold, try putting them in a mustard foot-bath before 
stepping into bed, and put on a pair of thick, dry woollen socks di- 
rectly afterwards. The socks can be removed as soon as the feet 
are warm. Feet that are constantly cold at night are never found 
in persons in the enjoyment of good health. 
Avoid all hot and heavy suppers, unless desirous of an attack 
of nightmare. A so-called “ severe tea ” late at night is usually 
unwholesome. Never go to bed, however, with an entirely “empty 
stomach.” This is often the cause of “insomnia,” or sleeplessness, 
especially in elderly persons. 
If troubled with sleeplessness, sponge the whole body before 
going to bed, and rub dry with a Turkish towel; use the dumb 
bells or any other gymnastic exercise, and jump into bed warm, 
and banish unpleasant thoughts. 
Finally, try to keep a clear conscience, an even temper, a light 
heart, and a good digestion. 
200. Asphyxia.—The word asphyxia, now com- 
monly applied to cases of suspended animation or ap- 
parent death from various causes, is a term derived 
from the Greek, and really means an “ absence of pulse.” 
The lungs, as we have learned, convert the dark and HINTS ON HYGIENE. 
187 
poisonous venous blood into life-renewing arterial 
blood. This change is effected through the pure tidal 
air which is breathed in by the lungs. In asphyxia, 
the supply of tidal air is in some way cut off. When 
the head is under water, as in drowning; when foul 
gases are inhaled, or when a foreign body stops up the 
air-passages, asphyxia may result. Death in such 
cases may be prevented by taking prompt measures 
that will insure the admission of abundance of fresh 
air into the lungs. 
201. Apparent Drowning.—In apparent drowning, 
the body should be taken from the water as soon as 
possible, and turned over upon its face for a moment. 
A finger should be swept around in the mouth to 
bring away any mucus or other substances that 
may be present. The body should be laid out flat on 
the back, wfith something a few inches high under the 
shoulders. The tongue should be drawn well forward 
and held out of the mouth by means of a handker- 
chief, and the effort to secure artificial respiration 
begun as follows: Some one should place himself on 
his knees behind the patient’s head, seize both arms 
near the elbows and sweep them around horizontally, 
away from the body and over the head till they 
meet above it, when a strong pull should be made 
upon them, and kept up two or three seconds. This 
effects an inspiration—fills the lungs with air, by 
drawing the ribs up and so enlarging the cavity of 
the chest. The second manoeuvre consists simply in 
returning the arms to their former position alongside 
the chest, and then making firm pressure against the 188 
FIRST LESSONS IN PHYSIOLOGY. 
lower ribs, so as to drive the air out of the chest and 
effect an act of expiration. This need occupy but a 
second of time. If this plan is regularly carried out, it 
will make about sixteen complete acts of respiration 
in a minute. It should be kept up for a long time, 
until a competent person has ascertained that the heart 
has ceased to beat. Warmth should be applied by 
heated flannels, or in any other convenient way ; and a 
stimulant should be given as soon as it can be swal- 
lowed. A teaspoonful to a tablespoonful of whiskey 
or brandy should be given every few minutes, until a 
decided effect is produced. As natural respiration 
begins to be attempted, it should be aided as much as 
possible by timing the artificial to it. When resusci- 
tation is accomplished, the person should be put in a 
warm bed, being carried carefully, with the head low, 
and a watch kept to see that the breathing does hot 
suddenly stop. 
202. Asphyxia from Noxious Gases. — Certain 
poisonous gases are given off’ during the burning of 
charcoal. Anthracite and bituminous coal, when 
burned in a close room, as a kitchen shut up for the 
night with an open stove of these burning coals, also 
give oft' noxious gases. Persons sleeping in such a 
room, unless awakened as the air becomes fouled, will 
be found senseless or dead soon after. Persons retiring 
at night may leave the gas “ turned down ; ” the flame 
becomes extinguished, and enough gas escapes to poison 
the inmates of the room. Asphyxia, or suffocation, 
from these or other noxious gases, calls for removal to 
the open air, dashing with cold water, stimulants, and HINTS ON HYGIENE. 
189 
the employment of artificial respiration, as described 
in speaking of apparent drowning. Risk of poison- 
ing from these sources can be obviated by leaving the 
window down from the top, and raising it a few inches 
from the bottom, thus securing proper ventilation. 
203. Heatstroke or Heat-Exhaustion.—Intense 
heat, either from the sun or from artificial sources, 
produces one of two conditions, either heatstroke or 
heat-exhaustion. Heatstroke, sometimes called sun- 
stroke, appears to be decidedly favored by intemper- 
ance, want of acclimatization, and debility. The skin 
is hot and dry, the pulse rapid, and the patient uncon- 
scious. The person attacked should at once be carried 
to a cool, airy spot. Unnecessary bystanders must be 
kept at a distance, as the person in this, as in every 
other accident, needs all the pure air he can get. The 
clothing should be removed, and the patient placed on 
his back, with the head raised a couple of inches by a 
folded garment. The entire body, particularly the 
head and chest, should be dashed with cold water in 
profusion, should be rubbed with ice, and ice should 
be applied to the head and spine. Physicians usually 
inject quinine beneath the skin. For heat-exhaustion, 
in which the body is cool, the skin moist, the pulse 
small, and the muscles relaxed, or sometimes convulsed, 
a few drops of laudanum in a tablespoonful of whiskey 
or brandy will be very useful. In these cases it has 
been found by physicians that morphia injected beneath 
the skin gives immediate relief. 
204. Fainting.—Persons sometimes fall in what is 
called a swoon or faint. An attack of fainting is ordi- 190 
FIRST LESSONS IN PHYSIOLOGY. 
narily not dangerous to life; although sometimes at- 
tacks which look like a simple faint are the result of 
serious disease of the heart or brain. The fainting 
person suddenly becomes pale, loses consciousness, and 
usually falls, the pulsations of the heart and the move- 
ments of breathing becoming diminished. In a faint, 
the brain is commonly deprived temporarily of its 
proper supply of blood. The individual in the faint 
should be carefully placed flat on the back, and the 
clothing loosened. In some cases it is well to raise 
the body and limbs a little above the level of the 
head; especially is this procedure called for when 
unconsciousness has been produced by a blow or any- 
thing giving rise to a decided shock. In this way the 
circulation will be given the best possible chance to 
right itself. Sprinkling cold water on the face, and 
applying ammonia water to the nostrils and warmth 
to the extremities and over the stomach, will also 
assist in bringing about reaction. 
205. Convulsions.—In convulsions, or “fits,” which 
are usually epileptic, movements calculated to injure 
the person must be controlled. It is useless to 
struggle against such as will do no injury; they had 
better be simply regulated, and no attempt made to 
entirely prevent them; but a folded towel or a piece 
of soft wood may be, when possible, thrust between 
the teeth, to prevent the usual biting of the tongue. 
If the clothing constricts any portion of the body 
sufficiently to interfere with the breathing, or the 
circulation of the blood, it should be loosened. 
When the height of the convulsion is passed, rest in HINTS ON HYGIENE. 
191 
the flat position, quiet, and sometimes a moderate 
stimulation, may be required. 
206. Burns or Scalds.—When clothes are on fire, 
the wearer must not run about, but should be made 
to lie down, and should be covered with a rug, or car- 
pet, or shawl, or coat—anything that will exclude the 
air and smother the flame. Afterward, the burned 
part must be disturbed as little as possible, and the 
patient may be enveloped in lint soaked in a mixture 
of equal parts of linseed-oil and lime-water. Stimulants 
and anodynes should be administered. Medical advice 
should always be taken in such grave circumstances. 
Slight burns are best treated by applying a cloth soaked 
in a strong solution of baking soda—the bicarbonate 
of soda. Linseed-oil and lime-water is also a good 
application for such burns. 
207. Sprains.—In a sprain the joint is twisted, 
and its ligaments are stretched or even torn. Sprains 
most frequently occur at the wrist and ankle-joints. 
The injury is rapidly followed by inflammation of the 
joint and adjacent parts, with great pain and often 
swelling. Sprains must be treated by rest, and heat 
or cold, as is best suited to each case. Sprains of the 
finger or wrist usually require cold and moist appli- 
cations. A lotion of lead-water and laudanum is use- 
ful to allay inflammation. To promote absorption of 
any inflammatory products that may be left, painting 
over the joint with tincture of iodine, and rubbing and 
kneading, are useful. 
208. Foreign Bodies in the Eye.—Particles of 
cinder, dust, or fragments of metal often get into the 192 
FIRST LESSONS IN PHYSIOLOGY. 
eye and cause trouble. A good plan is to hold a 
knitting-needle, or thin lead-pencil, over the upper 
lid; then, while the person looks, or turns his eye 
downward, seize the lashes of that lid by the fingers 
of the disengaged hand, and gently turn the lid up- 
ward and backward over the needle or pencil. Usually 
the intruder can be seen and removed. Should the 
foreign body be imbedded in the eyeball or the eyelid, 
the case should be left to a surgeon. The foreign 
body often cannot be seen, but the person assures us 
that he feels it. Often he does not really feel the 
body, but the roughness left by it. In such a case, 
or even if the body has been seen and removed, a 
soothing application to the injury is as useful as the 
same thing applied to a wound of the hand. A good 
eyewash is made by dissolving eight grains of borax 
in a mixture of one-half ounce of infusion of sassafras, 
and one ounce and a half of camphor water. Never 
draw a handkerchief, or anything else, between the 
eyelids to remove a foreign body. We know of one 
case in which the sight was almost destroyed as the 
result of an inflammation set up by dragging the for- 
eign body across the eyeball in this way. In fact, it 
is better not to meddle with the eye at all if a physi- 
cian can possibly be secured. 
209. Insects in the Ear.—Insects sometimes get 
into the ear. The best way of getting them out is to 
till the cavity of the ear with sweet-oil or glycerine. It 
drowns the animal by closing up its breathing pores, 
and in a short time it floats to the surface of the fluid 
used. The tube of the ear is somewhat curved, and HINTS ON HYGIENE. 
193 
when straightened by catching hold of the upper tip, 
and gently pulling it upward toward the crown of the 
head, the liquid flows in more readily. 
210. Foreign Bodies in the Throat.—Foreign 
bodies sometimes get lodged in the throat. A crust 
of. bread, or a bone, or some other object, may be 
lodged where it can be reached, when it is best re- 
moved with the fingers. Forceps may be used if at 
hand. If a piece of food is caught in the windpipe, 
owing to the epiglottis not shutting down quickly 
enough, usually it will be coughed out. If, how- 
ever, it remains, an effort should be made to re- 
move it with the fingers, and a physician should be 
called at once. Tickling the ear with a feather, or 
slapping the back with the hand, will sometimes excite 
coughing. 
211. Foreign Bodies in the Nose.—If a foreign 
body, such as a pebble or grain of coffee, gets into a 
nostril, the first thing to do is to try to expel it by 
gently blowing the nose. The nose should never be 
blown violently, for this may set up inflammation of 
the middle ear, and greatly impair the hearing. If 
ordinary blowing does not succeed, the child should 
be made to take a full breath ; then closing the other 
nostril and the mouth, when the lungs empty them- 
selves by expiration the foreign body may be driven 
out of the nostril. If it should not be expelled by 
either of these methods, a physician must be called. 
212. Bleeding from the Nose.—Bleeding from 
the nose can usually be stopped by application of cold 
water or ice to the outside and inside of the nostrils; 194 
FIRST LESSONS IN PHYSIOLOGY. 
but sometimes the bleeding is profuse and obstinate. 
Vinegar, or a strong solution of alum in warm water, 
can be snuffed up the nose; or cotton, soaked in vinegar 
or alum-water, may be used as a plug. The bleeding 
may frequently be stopped by pressing the finger with 
moderate firmness over the upper portion of the upper 
lip to the outer side of the nostril from which the 
blood proceeds. A small, hard roll of paper passed 
well up beneath the upper lip in the same situation is 
often sufficient. Water as hot as can be borne, carried 
into the bleeding nostril by gentle efforts at inspira- 
tion, while the mouth and opposite nostril are closed, 
in many cases is promptl}" effectual. Do not blow the 
nose during or soon after the bleeding; keep the mouth 
shut, and breathe through the nose. 
213. Bleeding from Wounds.—Capillary hemor- 
rhage follows every cut. The color of the blood is 
bright red; the flow is generally slow and not very 
considerable. It usually stops of itself. If it does 
not, cold water, ice, or vinegar may be applied. For 
oozing from a large raw surface, a towel may be folded, 
dipped in water as hot as the hand can bear, lightly 
squeezed, so as not to drip, and laid upon the bleeding 
surface. Bleeding from the veins is also generally slow 
and steady, the blood being of a darker color. The 
application of cold and continuous pressure upon and 
below the wound are the proper methods of treatment. 
Hemorrhage from the arteries is very dangerous. In 
such a case the blood is bright red, and spurts in a stream 
or leaps in jets from the divided vessel. For wounds 
of the arteries of the hand, raising the. hand above HINTS ON HYGIENE. 
195 
the head, and making firm pressure with the thumbs 
just above and in front of the wrist, will usually stop 
the bleeding. If this fails, and for wounds below the 
elbow, first grasp the upper part of the arm with both 
hands and squeeze as hard as possible; then let some 
one make a thick, hard knot, as big as an egg, in the 
middle of a handkerchief, place it over the middle of 
the front of the arm, immediately above the elbow, 
tie the ends tight at the back, and- bend the forearm 
up so as to press hard against the knot. This, if 
successfully done, will obstruct the main bloodvessel, 
which in this place lies in the middle line of the bend 
of the elbow. For wounds in the upper arm, a knot 
as big as a fist may be made in any piece of cloth, and 
shoved hard up into the armpit, and the elbow then 
brought straight down and held firmly against the side 
of the chest. The principal object is to obstruct the 
bloodvessel above the cut, and this can be effected 
by a knot placed, in the several cases, in front of the 
bend of the elbow, in the armpit; or for the lower 
extremity, behind the bend of the knee, or just below 
the groin, against which the nearest part of the limb 
is to be firmly pressed. 
214. Poisons in General.—Some knowledge of 
poisons and of the substances used to counteract their 
effects (antidotes) will frequently save valuable lives. 
Many poisonous substances are in common use as med- 
icines, for domestic purposes, or in the mechanic arts. 
Bottles or packages containing poisons should be care- 
fully labelled and kept out of the way of children. 
When a poison has been swallowed, it is a good plan 196 
FIRST LESSONS IN PHYSIOLOGY. 
to empty the stomach as speedily as possible. Vom- 
iting can be effected by several methods. Simple 
warm water, given cup after cup, is often all that will 
be necessary. A tablespoonful of ground mustard or 
of common salt can be mixed with a large tumblerful 
of water, and this can be given and repeated several 
times until vomiting is produced. After vomiting has 
commenced, warm water, flaxseed tea, or gum-arabic 
water may be given to continue the vomiting and 
soothe the stomach. Fat, oils, milk, raw eggs beaten 
up—all in moderate quantities—are especially valuable 
when the poison has been of an irritant character. If 
the sufferer is much depressed or cold, some stimulant, 
as hot tea, hot coffee, brandy, whiskey, or wine, may 
be administered. Warmth should also be applied. 
215. Different Classes of Poisons.—Poisons can 
be arranged into different classes: some are acids, some 
are alkalies; some are irritant mineral poisons, such 
as arsenic, sugar of lead, corrosive sublimate, tartar 
emetic, phosphorus, and lunar caustic; and some 
are special vegetable poisons, such as strychnia, opium, 
aconite, Jamestown weed, hemlock, nightshade, toad- 
stool, tobacco, etc., etc. Certain general principles of 
treatment apply for all the poisons of each special class. 
Acid Poisons.—The strong acids, such as sulphuric, nitric, and 
muriatic, are violent poisons, and yet are in common use, particu- 
larly in certain mechanical pursuits. The proper treatment for 
poisoning by any of these mineral acids is to give an alkali, as 
magnesia, lime, baking soda, whitewash, chalk, hartshorn mixed 
with plenty of water, etc. Vomiting should be provoked and bland 
liquids given. A little calcined magnesia in a case like this might be 
the means of saving a life. For oxalic acid, lime-water, chalk, white- HINTS ON HYGIENE. 
197 
wash, or even plaster crushed and stirred up in water, will answer. 
Carbolic Acid is a substance now much used as a medicine and 
as a disinfectant, and cases of poisoning from it occasionally occur. 
This odor, which is like that of creasote, should serve to put a per- 
son on guard with reference to the substance. Strong carbolic acid 
will corrode or burn the skin. If it should be accidentally poured 
or spilled upon the skin, the burn produced should be treated with 
cooling lotions, oils, or salves, as other burns. Taken internally, 
carbolic acid is a very poisonous substance. Besides the caustic 
or burning effect upon the mucous membrane of the mouth, throat, 
and alimentary canal, it exerts a peculiar effect upon the system, 
which shows itself by nausea or vomiting, sweating, lividity, labored 
breathing, feeble pulse, tremor, and paralysis. A good antidote for 
carbolic acid is the common Epsom salt or sulphate of magnesium. 
In case of poisoning by carbolic acid, therefore, after having tried 
to provoke vomiting, and after giving draughts of oil or milk to 
relieve the burning of the mouth and throat, a large quantity of 
Epsom salt should be dissolved in water and given freely to the 
sufferer. To accomplish the purpose for which it is given, the anti- 
dote must be administered early and in large amounts. 
Alkaline Poisons.—The strong alkalies are ammonia, or harts- 
horn, potash and soda, the latter two usually dissolved in water, 
the solution being generally called lye. Liniments sometimes con- 
tain ammonia, and are swallowed by mistake. Alkalies burn skin 
or mucous membrane rapidly and severely. The proper antidotes 
are mild acids, such as lemon juice or vinegar, which should be 
given in large quantity. 
Arsenic.—When arsenic has been taken, an antidote must be 
administered immediately, if life is to be saved. It can be obtained 
in the following manner: Take tincture of iron or Monsel’s solu- 
tion, and into it pour ammonia-water or some strong alkali; a 
precipitate will be obtained, which should be strained and given 
immediately, with large doses of calcined magnesia. Vomiting 
should be provoked or continued, and a dose of castor-oil should 
be given. Dialyzed iron, a preparation which can now be obtained 
from any drug-store, may be given in tablespoonful doses, following 
each dose by a tablespoonful of common salt in a teacupful of 
water. Paris green is an arsenical preparation. 198 
FIRST LESSONS IN PHYSIOLOGY. 
Sugar of Lead—For poisoning by sugar of lead, to produce 
vomiting, give Epsom salt, milk, eggs, and castor-oil. 
Corrosive Sublimate.—Corrosive sublimate dissolved in whiskey 
is an article frequently used to destroy vermin. If it should be 
swallowed by mistake, the stomach should be emptied by means 
of mild emetics; plenty of eggs and flour in soothing drinks should 
be given, and, later, sweet-oil. To relieve pain, and strengthen, 
opium in some form, and whiskey might also be required. 
Tartar Emetic.—By mistake, an overdose of tartar emetic may 
be administered. A strong decoction of good green tea, or oak 
bark, if taken soon, will change the tartar emetic into a harmless 
compound. 
Phosphorus.—Phosphorus is sometimes sucked from matches by 
children. It is a poison which acts slowly, and affords ample time 
for securing medical advice; but five-grain doses of sulphate of 
copper, dissolved in water, may be given at intervals of ten min- 
utes, until vomiting comes on. Then a dose of magnesia should be 
administered, but no fat oil. 
Lunar Caustic.—Lunar caustic is sometimes swallowed. The 
antidote for this is a very strong solution of salt and water given 
again and again; and vomiting should be provoked until the vom- 
ited matters cease to have a look like thin milk. 
Copper.—Vessels of copper often give rise to poisoning. Though 
the metal undergoes but little change in a dry atmosphere, it is 
rusted if acids be present, and its surface becomes covered with a 
green substance—one of the salts of copper,—a poisonous compound. 
It has sometimes happened that a mother has, for want of knowl- 
edge, thus poisoned her family. For poisoning with copper, milk, 
eggs, or baking soda should be given. 
Nux Vomica, or Strychnia.—For poisoning by nux vomica, or 
strychnia, use emetics or stomach-pump; chloral hydrate and bro- 
mide of potassium in large doses; chloroform to relieve spasm of 
glottis; stimulants, if needed; and morphia in one-grain doses, re- 
peated if necessary. 
Opium.—Opium, and its preparations, such as laudanum, pare- 
goric, black drop, many quack-medicines sold as soothing-syrups, 
etc., when taken in poisonous amounts, cause deep sleep, with 
narrowing of the pupil of the eye to a small circle, which does not SYLLABUS. 
199 
enlarge in the dark. Emetics must be used promptly and persist- 
ently, and frequent vomiting produced. Strong coffee must be 
freely given as a stimulant. So long as the breathing does not 
fall below ten to the minute, there is no immediate danger of 
death; but opium is a treacherous poison, and requires all the skill 
that can be obtained to combat it. The important matter is to 
keep up the breathing. If an electrical battery can be obtained 
and used, it is the best thing that can be done. The next is to 
lay the patient upon a lounge and slap his skin with the back of 
a broad brush or with a slipper. This is all the rousing that is 
necessary, so long as the breathing keeps above ten to the minute. 
Should it fall below this, or if the breathing should cease, artificial 
respiration should be employed. 
Special Vegetable Poisons.—Aconite, hemlock, deadly night- 
shade, the Jamestown weed, monk’s-hood, toadstools, and tobacco, 
in poisonous doses, all produce deep depression, and persons poi- 
soned by them must be treated with vomiting, followed by stimu- 
lation and warmth. 
Syllabus. 
Asphyxia is a term applied to cases of suspended animation or 
apparent death, caused by the supply of tidal air being in some way 
cut off from the lungs. 
When the head is under water, as in drowning, when foul gases are 
inhaled, or when a foreign body stops up the air-passages, asphyxia 
may result. 
In apparent drowning, the body should be taken from the water 
as soon as possible, and turned over upon its face for a moment; a 
finger should be swept around in the mouth ; the body should be laid 
on the back, with something a few inches high under the shoulders; 
the tongue should be drawn well forward and held out of the mouth, 
and the effort to secure artificial respiration should be attempted. 
When artificial respiration has been accomplished, warmth should 
be applied and stimulants given. 
Asphyxia is sometimes produced by noxious gases, and calls for 
removal to the open air, dashing with cold water, stimulants, and 
the employment of artificial respiration. 200 
FIRST LESSONS IN PHYSIOLOGY. 
Intense heat sometimes produces heat-stroke or sun-stroke, in which 
the skin is hot and dry, the pulse rapid, and the patient unconscious. 
The person attacked with heat-stroke should be carried to a cool, 
airy spot, his clothing should be removed, and his body should be 
dashed with cold water or rubbed with ice. 
Heat-exhaustion, also, results sometimes from intense heat. The 
body is cool, the skin moist, the pulse small, and the muscles relaxed 
or sometimes convulsed. A few drops of laudanum in a tablespoonful 
of whiskey or brandy will be found very useful. 
In a faint, as the brain is commonly deprived temporarily of its 
proper supply of blood, the individual should be placed on the back 
and the clothing loosened; in some cases it is well to raise the body 
and limbs a little above the level of the head. 
Sprinkling cold water on the face, ammonia to the nostrils, and 
warmth to the extremities and over the stomach will also assist in 
bringing about reaction from a faint. 
In convulsions which are usually epileptic, the patient should be 
prevented from injuring himself. 
When clothes are on fire, the wearer should be made to lie down, 
and should be covered with anything that will exclude the air and 
smother the flame. Afterward, the burned part must be disturbed 
as little as possible, and the patient may be enveloped in lint soaked 
in a mixture of equal parts of linseed-oil and lime-water. Stimu- 
lants and anodynes should be administered. 
Slight burns are best treated by applying a cloth soaked in a strong 
solution of baking soda—the bicarbonate of soda. Linseed-oil and 
lime-water is a good application for such burns. 
Sprains must be treated by rest and heat or cold, as is best suited 
to each case. Sprains of the finger or wrist usually require cold and 
moist applications. A lotion of lead-water and laudanum is useful 
to allay inflammation. To promote absorption of any inflammatory 
products that may be left, painting over the joint with tincture of 
iodine and rubbing and kneading are useful. 
When foreign bodies get into the eye, a good plan is to hold a knit- 
ting-needle, or thin lead-pencil, over the upper lid while the person 
looks, or turns his eyes downward; then seize the lashes of that lid 
by the fingers of the disengaged hand, and gently turn the lid up- 
ward and backward over the needle or pencil. Usually the intruder 
can be seen and removed. Should the foreign body be imbedded in 
the eyeball or the eyelid, the case should be left to a surgeon. SYLLABUS. 
201 
A good eyewash is made by dissolving eight grains of borax in a 
mixture of one-half ounce of infusion of sassafras and one ounce and 
a half of camphor water. 
Never draw a handkerchief, or anything else, between the eyelids 
to remove a foreign body. 
When insects get into the ear, the best way of getting them out is 
to fill the cavity of the ear with sweet-oil or glycerine. It drowns 
the animal by closing up its breathing pores, and in a short time it 
floats to the surface of the fluid used. 
When foreign bodies get lodged in the throat, they may sometimes 
be removed with the fingers or with forceps. 
If a piece of food is caught in the windpipe, owing to the epiglottis 
not shutting down quickly enough, it will usually be coughed out. 
Tickling the ear with a feather, or slapping the back with the hand, 
will sometimes excite coughing. If, however, it remains, an effort 
should be made to remove it with the fingers, and a physician should 
be called at once. 
If a foreign body, such as a pebble or grain of coffee, gets into a 
nostril, the first thing to do is to try to expel it by gently blowing 
the nose. If ordinary blowing does not succeed, the child should be 
made to take a full breath, then closing the other nostril and the 
mouth, when the lungs empty themselves by expiration, the foreign 
body may be driven out of the nostril. 
Bleeding from the nose can usually be stopped by application of 
cold water or ice to the outside and inside of the nostrils; but some- 
times the bleeding is profuse and obstinate. Vinegar, or a strong 
solution of alum in warm water, can be snuffed up the nose; or 
cotton soaked in vinegar or alum-water may be used as a plug. 
The bleeding may frequently be stopped by pressing the finger 
with moderate firmness over the upper portion of the upper lip to 
the outer side of the nostril from which the blood proceeds. A small, 
hard roll of paper passed well up beneath the upper lip, in the same 
situation, is often sufficient. Water as hot as can be borne, carried 
into the bleeding nostril by gentle efforts at inspiration while the 
mouth and opposite nostril are closed, in many cases is promptly 
effectual. Do not blow the nose during or soon after bleeding. 
Keep the mouth shut and breathe through the nose. 
Capillary hemorrhage follows every cut. It usually stops of itself. 
If it does not, cold water, ice, or vinegar may be applied. For oozing 
from a large raw surface, a towel may be folded, dipped in water as 202 
FIRST LESSONS IN PHYSIOLOGY. 
hot as the hand can bear, lightly squeezed, so as not to drip, and laid 
upon the bleeding surface. 
Bleeding from the veins is also generally slow and steady The 
application of cold and continuous pressure upon and below the 
wound are the proper methods of treatment. 
Hemorrhage from the arteries is very dangerous. The blood is 
bright red, and spurts in a stream or leaps in jets from the divided 
vessel. 
For wounds of arteries of the hand, raising the hand above the 
head, and making firm pressure with the thumbs just above and in 
front of the wrist, will usually stop the bleeding. If this fails, and 
for wounds below the elbow, first grasp the upper part of the arm 
with both hands and squeeze as hard as possible ; then let some one 
make a thick, hard knot, as big as an egg, in the middle of a hand- 
kerchief ; place it over the middle of the front of the arm, immediately 
above the elbow; tie the ends tight at the back, and bend the forearm 
up so as to press hard against the knot. 
For wounds in the upper arm, a knot as big as a fist may be made 
in any piece of cloth, and shoved hard up into the armpit, and the 
elbow then brought straight down and held firmly against the side 
of the chest. 
The principal object in arterial bleeding is to obstruct the blood- 
vessel above the cut, and this can be effected by a knot placed, in the 
several cases, in front of the bend of the elbow, in the armpit; or, for 
the lower extremity, behind the bend of the knee, or just below the 
groin, against which the nearest part of the limb is to be firmly pressed. 
When a poison has been swallowed, it is a good plan to empty the 
stomach as speedily as possible. Vomiting can be effected by sev- 
eral methods. Simple warm water, given cup after cup, is often all 
that will be necessary. A tablespoonful of ground mustard or of 
common salt can be mixed with a large tumblerful of water, and this 
can be given and repeated several times until vomiting is produced. 
After vomiting has commenced, warm water, flaxseed tea, or gum- 
arabic water may be given to continue the vomiting and soothe the 
stomach. 
Fats, oils, milk, raw eggs beaten up—all in moderate quantities— 
are especially valuable when the poison has been of an irritant char- 
acter. If the sufferer is much depressed by cold, some stimulant, as 
hot tea, hot coffee, brandy, whiskey, or wine, may be administered. 
Warmth should also be applied. QUESTIONS FOR REVIEW. 
203 
Poisons can be arranged into different classes: some are acids, some 
are alkalies; some are irritant special mineral poisons, such as ar- 
senic, sugar of lead, corrosive sublimate, tartar emetic, phosphorus, 
lunar caustic ; and some are special vegetable poisons, such as strych- 
nia, opium, aconite, Jamestown weed, hemlock, nightshade, toadstool, 
tobacco, etc., etc. Certain general principles of treatment apply for 
all the poisons of each special class. 
Questions for Review. 
How often should the whole body be washed ? 
What is the least that one can do with any attention to cleanliness 
or health ? 
Describe the best process for a thorough wash of the hands. 
How often should a hot bath be taken ? 
What is said about the use of a flesh-brush or rough towel ? 
When should the teeth be brushed ? 
How should the hair be combed and brushed at night ? 
When should the mouth be rinsed out? 
Should tooth-brushes be soft or hard ? Why ? 
Wtiat is said about pomade? 
What is said about oiling the hair? 
How may sweet-oil be of service to the body ? 
Should hot fluids be drunk? 
How should sweets, tarts, pastry, confectionery, and sugar be used ? 
What should be done to the clothes before going to bed ? 
What should be done to the bed and bedroom in the morning? 
What should always be done before sitting down to breakfast ? 
When and how should those sick with fever, or any infectious dis- 
ease, be visited ? 
What precaution should be taken to avoid infection or any low 
fever ? 
Mention some good disinfectants and the methods of using them. 
How should cold feet at night be treated ? 
Why should hot and heavy suppers be avoided? 
What does going to bed with an entirely empty stomach often 
cause ? 204 
FIRST LESSONS IN PHYSIOLOGY. 
Mention some good rules of hygiene for those troubled with sleep- 
lessness. 
To what is the word asphyxia now commonly applied ? 
What is the derivation of the word ? 
In asphyxia, what happens to the tidal air ? 
Mention some of the ways in which asphyxia is produced. 
How may death be prevented in cases of asphyxia ? 
Describe what should he done in apparent drowning. 
Name some of the noxious gases which may produce asphyxia. 
What is the treatment for asphyxia or suffocation from noxious 
gases ? 
How may risk of poisoning from noxious gases be obviated ? 
What two conditions may be produced by intense heat ? 
By what is sunstroke decidedly favored ? 
What are the symptoms of heatstroke or sunstroke ? 
What treatment should be adopted for a person attacked with sun- 
stroke ? 
How should a case of heat-exhaustion be treated ? 
Is an attack of fainting ordinarily dangerous to life ? 
Describe a faint. 
What happens to the brain in a faint ? 
What should be done to the individual in a faint ? 
What movements should be controlled in a case of convulsions ? * 
What are the suggestions with reference to the treatment of a 
convulsion ? 
When clothes are on fire, what should the wearer do ? 
Afterward, how should the burned part be treated? 
What should be given internally ? 
How are slight burns best treated ? 
What is the condition in a sprain ? 
Where do sprains most frequently occur? 
By what is the injury followed ? 
How should sprains be treated ? 
What is a good plan for removing foreign bodies from beneath the 
eyelids ? 
What advice is given when the foreign body is imbedded in the 
eyeball or eyelid ? 
What should be done for the irritation remaining after the removal 
of a foreign body ? 
How can a good eye-wash be made ? QUESTIONS FOR REVIEW. 
205 
Should a handkerchief ever be drawn between the eyelids to re- 
move a foreign body ? 
What is the best method of getting an insect out of the ear ? 
Mention some of the methods of removing foreign bodies from the 
throat. 
Mention some of the methods of removing foreign bodies from the 
nose. 
How can bleeding from the nose usually be stopped ? 
If the bleeding is profuse and obstinate, how may it be stopped ? 
What sort of hemorrhage follows every cut ? 
If capillary hemorrhage does not stop of itself, how may it be con- 
trolled ? 
How can bleeding from the veins be controlled ? 
What is the most dangerous form of hemorrhage ? 
How can bleeding from wounds of the arteries of the hand usually 
be stopped ? 
Give the methods of controlling arterial hemorrhage from wounds 
below the elbow. 
Give the methods for wounds in the upper arm, and for wounds in 
the lower extremities. 
What are antidotes ? 
When a poison has been swallowed, what should be done at once ? 
How can vomiting be effected ? 
After vomiting has commenced, what should be given ? 
What are especially valuable when the poison has been of an irri- 
tant character ? 
What should be done if the sufferer is much depressed or cold ? 
Name some of the classes into which poisons can be arranged. 
What is the proper treatment for the strong mineral acid poisons ? 
What is the treatment for oxalic acid poisoning ? 
How will strong carbolic acid act on the skin ? 
How should a burn produced by it be treated ? 
What is a good antidote for carbolic acid ? 
Give the entire plan of treatment in poisoning by carbolic acid. 
Mention some of the alkaline poisons. 
What are the proper antidotes for alkaline poisons ? 
Describe the method of making an antidote for arsenic. 
What should be done besides administering an antidote ? 
What is the name of a common arsenical preparation ? 
For poisoning by sugar of lead, what should be done ? FIRST LESSONS IN PHYSIOLOGY. 
Give the treatment for corrosive sublimate poisoning. 
Give the treatment for tartar emetic poisoning. 
How are children sometimes poisoned by phosphorus? 
How should such cases be treated ? 
What is the antidote for lunar caustic ? 
How do vessels of copper often give rise to poisoning ? 
For poisoning with copper, what should be given? 
What is the treatment for poisoning by nux vomica, or strychnia? 
What are some of the preparations of opium ? 
What symptoms are caused by opium preparations when taken in 
poisonous amounts? 
What is the treatment for opium poisoning? 
What symptoms are produced by poisonous doses of aconite, hem- 
lock, deadly nightshade, the Jamestown weed, monk’s-hood, toad- 
stools, and tobacco ? 
How should persons poisoned by these substances be treated ? 
The 
End.