THE 
ESSENTIALS OF HEALTH 
a Ceft»Boofi 
ON 
ANATOM physiology, hygiene, 
AIXOHol, and narcotics 
BY 
CHARLES H. JTOWELL, M.D. 
LATE PROF£ SfoR eftfl9T6l$$r> MICROSCOPY, AND ASSISTANT PROFESSOR OF 
UNIVERSITY OF MICHIGAN. 
AUTHOR OF “STuP£teTs MANUAL OF HISTOLOGY,” “MICROSCOPICAL DIAGNOSIS,” “THE 
STRUCTURE OF TEETH,” “a HEALTHY BODY,” “A PRIMER OF HEALTH,” ETC. 
LATE EDITOR OF “ THE MICROSCOPE” 
EDITOR OF “THE NATIONAL MEDICAL REVIEW.” 
FULLY ILLUSTRATED 
WITH ORIGINAL SKETCHES BY THE AUTHOR 
SILVER, BURDETT & COMPANY 
New York . . . BOSTON . . . Chicago 
1893 3finiJors*ment. 
TATE have examined the schoool text-book entitled “The Essentials 
' ' of Health,” by Doctor Charles H. Stowell. 
As it faithfully teaches the nature of alcoholic drinks and other 
narcotics in connection with relative physiology and hygiene, and in 
language well adapted to grade, we heartily commend and indorse it 
for Grammar Grade pupils or schools. 
National and International Supt. Dept, of Scientific Temperance 
Instruction of the Woman’s Christian Temperance Union. 
MARY H. HUNT, 
Albert H. Plumb, D.D., N 
Daniel Dorchester, D.D., 
Hon. William E. Sheldon, 
Rev. Joseph Cook. 
Advisory Board 
for 
United States of America. 
Copyright, 1892, 
By Silver, Burdett and Company. 
Press: 
John Wilson and Son, Cambridge. PREFACE. 
This book has been prepared for pupils who have 
studied the preceding number of this series, A Healthy 
3ody, or a work of like grade. It will meet the require- 
ments for advanced study in public and private schools, 
n high schools and academies, and is well adapted to 
:he needs of the general reader. 
The illustrations are from original pen sketches drawn 
by the author. In nearly every instance these sketches 
were made from specimens especially prepared by the 
author for this series of books. 
The treatment of the subject of anatomy is sufficient 
to form the foundation for physiological study; physi- 
ology is given with sufficient fullness to elucidate the 
principal features of the subject, and to enable the pupil 
to comprehend easily the laws for the preservation of 
health; hygiene is dwelt upon with such completeness 
that the ordinary laws of health need not be ignorantly 
broken; while the subjects of alcohol and tobacco are 
discussed with such care and in such detail as to show 
that the use of these narcotics by the young may not 
only diminish their powers and dwarf them physically, 
but may even altogether arrest the mental, moral, and 4 
PREFACE. 
physical development. No thoughtful person can study 
the effects of alcohol and tobacco on the growing body 
without becoming seriously impressed with the great 
power for evil which these drugs possess. The evi- 
dence is already convincing, and is daily accumulating, 
that the future welfare of our youth, and, therefore, the 
future welfare of our country, demands that both these 
poisons be placed beyond the reach of the young. 
A knowledge of the fundamental principles of an- 
atomy and physiology, together with a knowledge of 
those things which are desirable and of those which 
should be shunned, will do much toward the develop- 
ment of a noble manhood and womanhood. 
Charles H. Stowell. 
Washington, D. C., 
July, 1892. CONTENTS. 
Chapter Page 
I. Cells 11 
H. Foods 17 
III. The Nitrogenous Foods 23 
IY. The Non-Nitrogenous Foods. — Cooking ... 31 
Y. Alcohol 40 
YI. Additional Facts about Alcohol 50 
VII. Digestion 57 
VIII. Digestion in the Stomach and Intestine ... 70 
IX. Absorption 84 
X. The Blood 93 
XI. The Circulation 103 
XII. Respiration 124 
XIII. Ventilation 140 
XIV. The Kidneys 151 
XV. The Bones 156 
XVI. The Skeleton 164 
XVII. The Muscles 180 
XVIII. Exercise . . . 191 
XIX. The Skin «... 202 
XX. Bathing.—Clothing 215 
XXI. Animal Heat 224 
XXII. The Eppects op Tobacco 233 
XXIII. What Tobacco costs: in Body; in Mind; in 
Morals; and in Monet 240 6 
CONTENTS. 
Chapter Page 
XXIY. Opium. — Chloral 250 
XXY. The Anatomy of the Nervous System . . . 253 
XXVI. The Physiology of the Nervous System . . . 267 
XXVII. The Hygiene of the Nervous System .... 277 
XXVIII. Alcohol and the Nervous System 283 
XXIX. The Sense of Sight 296 
XXX. The Senses of Taste and Smell 306 
XXXI. The Sense of Hearing 316 
XXXII. The Senses of Touch; Temperature; Weight; 
Pressure; Common Sensation; and Pain . . 323 
XXXIII. Additional Testimony against Alcohol and To- 
bacco 329 
XXXIV. Emergencies 343 
INDEX 347 INTKODUCTION. 
The anatomist teaches that the body is composed of 
tissues and fluids. A number of tissues are often so 
united that the part can best perform some special work 
or function. Such a part is called an organ ; as, the eye 
is the organ of sight, and the ear, the organ of hearing. 
Tissues which have a similar structure are grouped to- 
gether into systems. Thus we have the muscular sys- 
tem, and the nervous system. Tissues are also grouped 
according to their functions, each group receiving the 
name of an apparatus. To illustrate, we have the di- 
gestive apparatus, and the respiratory apparatus. 
The histologist teaches that each tissue is composed 
of most minute parts. These are in the form of fibrils 
and cells. To study these anatomical elements requires 
the aid of the highest powers of the microscope. Yet a 
study of the life history of a single cell often reveals 
many of the wonderful phenomena of the whole body. 
The microscope brings man in closest relations with 
nature, and renders clear many of her mysterious 
processes. 
The chemist teaches that the body is composed of a 
number of chemical elements. These include such well- 8 
INTRODUCTION. 
known elements as carbon, hydrogen, oxygen, and nitro- 
gen, together with a number of others. These elements 
form certain combinations and give rise to certain 
chemical processes. The chemist also informs us that 
the arrangement of these elements can be disturbed by 
certain forces and a new arrangement formed, by which 
entirely new substances appear. Thus we find that the 
growing plant can take carbonic acid gas (which is com- 
posed of carbon and oxygen) and water (which is 
composed of hydrogen and oxygen), break up the ar- 
rangement of their elements, and rearrange them so 
that starch (which is composed of carbon, oxygen, and 
hydrogen) is deposited in the leaves. Starch is ap- 
parently unlike the two elements from which it is 
formed; yet it is composed of the same chemical ele- 
ments, only these are differently arranged and in dif- 
ferent proportions. The proportions are different 
because when the growing plant breaks up the car- 
bonic acid gas it sets the oxygen free, and unites the 
carbon with the hydrogen and oxygen of the water. 
By adding more hydrogen and oxygen to the starch, the 
living plant can change the starch to sugar. 
The physiologist teaches of the active phenomena pre- 
sented by living beings. The peculiar action of a par- 
ticular organ is called its function. It is evident that 
physiology is best studied by carefully observing living 
creatures, — by the direct observation of nature. From 
the study of a dead tissue we are unable to infer, by any 
process of reasoning, what its living actions were. For 
instance, there is nothing about the structure of a nerve INTRODUCTION. 
9 
from which we can reason that it conveys a sensation of 
pain, or a stimulus for the contraction of a muscle. 
Neither is there anything in the structure of the gastric 
glands from which we might reason that they secrete 
a digestive fluid. Physiological properties are not as- 
certained by anatomical examination. 
The hygienist teaches a system of principles and 
rules, based upon a knowledge of anatomy, physiology, 
and chemistry. These rules have for their main object 
the preservation of the health; it may be the health of the 
individual, or that of an entire community. Hygiene is 
the practical result obtained from a study of the science 
of medicine. By a proper observance of its laws, the 
individual is enabled to accomplish his best work; while 
he is also able to prevent much sickness and to reduce 
its severity when present. 
The laws of health should inform us not only con- 
cerning those things which tend directly to the promo- 
tion of health, but also concerning those which must he 
avoided if health is to be maintained. As the evidence 
is overwhelming that alcohol and tobacco exert a most 
pernicious influence on the growing body, the effects 
of these drugs should be carefully and fully set forth, 
that the individual may be informed of the danger which 
attends their use. These drugs are specifically named 
because it is believed that the very wide use they have 
gained is largely due to ignorance of their nature. 
What is said of alcohol and tobacco may with propriety 
be said of several other narcotics, as opium, the use of 
which is not so prevalent in this country. All these INTRODUCTION. 
10 
stimulants and narcotics tend to sap the vital forces, 
weaken the will, and undermine the moral character. 
The great value of sound health, of the individual and 
of the community, has given rise to organized effort in 
the form of Boards of Health in all our large cities, and 
in most if not all of the States of the Union. These 
Boards and Sanitary Commissions have done much, not 
only to arrest the spread of disease but to prevent its 
appearance. The subject is one of such vital importance 
that it appeals to intelligence everywhere. It has en- 
listed the best thought of the wisest men and women 
for many years. Manifestly, therefore, it is unnecessary 
to offer any apology for the prominence given to the 
essentials of health in the pages of this volume. THE 
ESSENTIALS OF HEALTH. 
CHAPTER I. 
CELLS. 
General Description. The whole body is composed 
largely of cells ; while each individual part consists 
of cells quite characteristic in shape and size. By 
studying these cells we learn much of the anatomy 
and physiology of the whole system. 
Some cells are so minute that very high powers of the 
microscope are required to see them, while others are 
nearly large enough to be seen with the unaided eye. 
In shape, there is the greatest variation. There are 
spherical, oval, and spindle-shaped cells; cells wTith 
branches extending in various directions ; and still 
other cells with six equal sides. In color, there are 
the extremes from the black to the colorless ; and from 
the brown to the yellowish green. There exists, there- 
fore, a great variety in the shape, size, and color of 
cells. 
Their Structure. Living cells consist of a transparent, 
jelly-like material, called protoplasm. The microscope 
shows that there are two parts to a cell: the body, or the 12 
THE ESSENTIALS OF HEALTH. 
greater part of the cell ; and the nucleus, or the smaller 
part in the centre. The nucleus is usually spherical 
or oval, and, with few exceptions, is found in all cells. 
In rapidly growing cells two or more nuclei are often 
found. The nucleus of a cell can be shown very clearly 
by adding a carefully prepared solution of carmine, and 
then examining with the microscope. The carmine 
stains each nucleus bright red, but does not affect the 
body of the cell. 
The accompanying colored plate illustrates the results 
of carmine-staining on a variety of cells : (1) mucous 
cells, found wherever mucus is secreted; (2) columnar- 
cells, surrounding the villi of the small intestine; 
(3) cells from connective tissue; (4) ciliated cells from 
the trachea; (5) flattened epithelium from the mucous 
membrane of the mouth; (6) liver cells; (7) cells 
from the surface of the body; these cells have no 
nuclei; (8) cells from the salivary glands ; (9) cells 
lining the cavities of the heart; (10) pigment cells from 
the eye. 
The Life of a Cell. It is probable that the great ma- 
jority of cells are, comparatively speaking, short-lived. 
We must remember that the body is constantly and 
rapidly changing. Each movement of the body, each 
activity of a part, must cause a wear and waste of 
tissue ; and this loss must be replaced by new mate- 
rial within a short time. 
There are many ways of showing that the body is ever 
wasting away. If a drop of saliva be placed under the 
microscope, a vast number of thin cells can be seen. 
These cells come from the mucous membrane lining the 
mouth. The motion of the tongue, lips, and cheeks, as PLATE I. CELLS. 
13 
in speaking, eating, and drinking, remove vast numbers 
of these bodies. Then again, the surface of the whole 
body is covered with cells, many layers deep. The 
outer cells are easily removed, by the friction of the 
clothing, and by the use of the sponge and towel at 
the daily bath. In this way immense numbers of cells 
are being constantly destroyed, while new ones are as 
rapidly being formed beneath the surface to take their 
places. 
A more familiar example will illustrate this point. 
The finger nails are composed of cells so minute that 
a high power of the microscope is required to see them. 
Each paring of the nail, therefore, must remove vast 
numbers of these cells ; and yet, how rapidly even this 
hard structure grows. Thus we learn that the body is 
ever changing; the old, worn-out, and useless material 
being constantly cast off, and the new as regularly tak- 
ing its place. 
Some cells are much longer-lived than others. It is 
probable that the cells found in such hard tissues as 
bone and cartilage undergo comparatively slow changes, 
while the cells in some of the glands change with great 
rapidity. In fact, the whole life history of a cell in 
some of the most active glands may be covered by 
a few hours. 
Growth and Development. Cells increase both in size 
and number. After reaching certain dimensions, how- 
ever, they cease to grow. They may then either maintain 
that size for the remainder of their life, or they may, 
by a peculiar process of division, become temporarily 
smaller. This process is called cell division. When a 
cell is about to divide, its nucleus becomes constricted in 14 
THE ESSENTIALS OF HEALTH. 
the center, assuming a dumb-bell shape. This con- 
striction increases until the nucleus becomes divided 
into two nuclei. Then the body of the cell under- 
goes the same change in form until it has divided 
Fig. 1. Diagram illustrating the division of cells : (1, 2, 3, 4, 5,) by 
cell division ; (6, 7, 8,) by budding. 
into two cells, with one nucleus for each cell. Another 
method of division is that where a process, or bud, 
protrudes from the body of the cell. Soon this sepa- 
rates from the original cell, and a nucleus is developed 
within it. 
Some Cells have Motion. The great majority of the 
cells in the body are fixed and cannot alter their shape 
or position. There are some, however, that not only 
have the power to change their shape, but also to move 
from place to place. These movements are known as 
the “ amoeboid movements,” so named from an animal 
called the amoeba. 
The amoeba is the lowest form of animal life. It 
is of jelly-like consistence, and averages from the 
to the 25V0 an diameter. It is found in 
stagnant water, and in water in which there is decay- 
ing animal matter. The amoeba is an object of intense 
interest to all physiologists, because it represents both 
a single cell and a whole individual. It is remark- 
able for its constant and rapid changes of form, CELLS. 
15 
causing it to move about in any direction. The amoeba 
is an animal, the lowest in the scale; yet it moves ; 
Fig. 2. Various forms assumed by an amoeba. These sketches were 
made from the same amoeba, at intervals of a few seconds. 
it takes nourishment; it reproduces its own kind ; 
and it dies. 
The Function of Cells. Certain cells are set apart 
to perform certain work, and they can do no other. 
These groupings are called glands, tissues, and organs. 
The cells of the salivary glands can take digested food 
from the blood, and change it into the tissue of the sal- 
ivary glands. The cells of muscle can take something 
from the blood and build from it true muscular tissue. 
The cells of the skin take the same nourishment from 
the blood, and make from it the soft covering for the 
body. Thus, while a person may eat only one kind of 
food, it is possible for this food to be changed into all 
the various structures of the body. 
This is not the work of any one organ ; it is the 
combined work of the cells of all the organs and tis- 
sues of the body. Each cell, therefore, can take ma- 
terial from the blood, and change it into its own 
structure. But the cell can do even more than this; 
it can take material from the blood and change it into 
a substance unlike its own. For instance, a cell in 
one of the salivary glands can take some material 16 
THE ESSENTIALS OF HEALTH. 
brought to it by the blood, and completely change it 
mto saliva; or a cell in one of the glands of the stom- 
ach can take material from the blood and change it 
into gastric juice. We learn that each cell in the 
body has its own work to do, and that this work is 
constant and rapid. 
ALCOHOL AND TOBACCO. 
It must be evident that deficiency of food, or any in- 
jurious substance brought into contact with the cells, 
must seriously interfere with the health of the body. 
Any substance which will contribute to the normal 
growth and activity of the cells is greatly to be desired, 
while anything which would impair these should be 
avoided. We should remember, also, that all young 
and rapidly growing cells are much more sensitive to 
foreign substances than are those which are fully devel- 
oped. Alcohol and nicotine, being foreign substances 
and poisons, retard the healthy action and growth of 
the cells. 
QUESTIONS. 
1. What is said about the size, shape, and color of cells? 
2. Give the structure of cells. 
3. Give illustrations proving that the body is ever wasting away. 
4. How do cells increase in number ? 
5. Give a description of the amoeba. 
6. What is the work of the cells? 
7. What can each individual cell do ? 
8. How do alcohol and tobacco affect the growth of the cells ? FOODS. 
17 
CHAPTER II. 
FOODS. 
Waste and Repair. We must keep in mind that each 
activity of the body is followed by a waste of material, 
and that this change is constant throughout life. As 
the body is always wasting away, so should it always be 
undergoing repair. The processes of waste and repair 
do not always bear the same relation to each other. 
Early in life the building up greatly exceeds the break- 
ing down; more material is supplied than is worn out 
and removed; the processes of repair exceed those of 
waste, and the body grows and develops. Later in life 
the repair and waste are nearly balanced, and for a 
number of years the form and weight remain about the 
same. As old age comes on, the weight diminishes and 
all the forces of man become less active. The waste 
now exceeds the repair. 
From the food we eat, the body must obtain the mate- 
rials for building its structure and for keeping it in re- 
pair. It is clear, viewed in this light, that the subject 
of foods is of the -utmost importance. 
Uses of Foods. The first use of foods, therefore, is to 
supply material from which the body may be built up 
and kept in repair. Other uses are, to supply heat for 18 
THE ESSENTIALS OF HEALTH. 
the body; to give strength ; and to dissolve substances 
and aid in their distribution. If it is the nature of a 
substance to injure a healthy organ, or in any way 
interfere with its action, it cannot be called a food. 
Classification of Foods. All three of Nature’s kingdoms 
are called upon to furnish articles of food. The princi- 
pal articles obtained from the mineral kingdom are water 
and salt; from the vegetable kingdom, such cereals as 
wheat, corn, and oats, and a large number of vegeta- 
bles, such as potatoes and fruits ; from the animal king- 
dom, the various meats, milk, and eggs. 
For purposes of study, foods are divided into the 
organic and inorganic. The organic foods are obtained 
from living substances, or from things which once had 
life. The inorganic foods are derived from such inor- 
ganic substances as the air, the earth, and the water. 
THE INORGANIC FOODS. 
The two principal inorganic foods are water and salt. 
These are used by themselves, or are added to the food 
in cooking. 
Salt. Salt is found in all the tissues and organs of 
the body, except the enamel of the teeth. It is esti- 
mated that there is nearly one quarter of a pound of 
salt in the entire body. In a small amount, salt is pres- 
ent in nearly all the organic foods in use, but not in 
sufficient quantity to meet the demands of the system. 
That salt is a necessary food is indicated by the natural 
craving for it, not only in man, but in the lower animals 
as well. Animals on the prairies, like the buffalo for FOODS. 
instance, will travel many miles in search of salt; while 
the sheep come quickly to the farmer’s call, expecting 
some of this necessary food. These animals, together 
with others living upon the grasses, do not obtain a suf- 
ficient supply of salt with their food; while those ani- 
mals living principally upon meats receive a proper 
amount, as it is already in the meat itself. Such animals 
may even have a repugnance for salted meats. 
19 
Salt gives a flavor to the food. Food may be very 
nutritious, yet if it be tasteless it is not eaten readily, 
and is digested with difficulty. Salt stimulates the ap- 
petite, excites a flow of the saliva and gastric juice, and 
thus aids in the whole process of digestion. 
Water. Water constitutes nearly three fourths of the 
weight of the entire body. It is universally present 
in all the tissues and fluids of the body. There are 
many reasons why water is so important. All the food 
must be dissolved before the processes of digestion and 
absorption can be completed. The water in the tissues 
holds in solution numerous substances, which represent 
some of the waste materials of the body. 
Water gives elasticity to the bones, the muscles, the 
tendons, and the other tissues. Through the blood and 
tissues it becomes a circulating medium for conveying 
the foods, which are held in solution, to all parts of the 
body, and for taking away from the tissues the worn- 
out and useless ingredients. It is due to the presence 
of water that each tissue has its special consistency. 
Water is the most important substance used as food, as 
it is the one universal solvent. It thus becomes the 
medium for carrying dissolved materials from place to 
place, leaving and taking, as nature directs. The crav- 20 
THE ESSENTIALS OF HEALTH. 
ing for water is greater than for any other food, and 
a person will die sooner, if deprived of it, than if de- 
prived of solid food. 
A large quantity of water is taken into the system 
during each day. Some of this is taken purposely, as 
a drink, while a large amount is taken with the food. 
To prove the truth of this latter statement, we have 
only to recall the fact that one half the weight of beef, 
three fourths the weight of potatoes, and nine tenths 
the weight of milk, consist of water. A healthy man 
takes, on an average, about two quarts of water each day. 
Sources of Water. Rain water most closely resembles 
distilled, or chemically pure water; it usually contains 
a small amount of carbonic acid gas. Spring water 
contains a considerable amount of mineral substances 
and carbonic acid gas, the latter giving to spring water 
its fresh taste. The carbonic acid aids in dissolving the 
mineral substances as the water permeates the soil. 
Spring water contains but little oxygen ; therefore vege- 
table organisms usually flourish in it, while animal life, 
which requires much oxygen, is poorly represented. 
Spring water may bubble to the surface of the earth, 
or some mechanical device, as a pump, may be neces- 
sary to bring it within reach. 
The running water of rivers does not contain so much 
mineral matter as does spring water. When brought 
to the surface, spring water rapidly gives off its carbonic 
acid, causing a deposit of some of the mineral sub- 
stances. Running water absorbs oxygen readily from 
the air, and being deficient in carbonic acid and rich in 
oxygen, it affords the necessary conditions for animal 
life. Drinking water is obtained chiefly from springs, FOODS. 
21 
and usually some form of a pump is necessary to bring 
it to the surface. 
The Purity of Drinking Water. Drinking water should 
be colorless and without the slightest odor. Chemically 
pure water,, however, is not pleasant to the taste; it 
lacks the snap and tartness of spring water. Then, 
too, the presence of some minerals in solution is useful 
to the system. Lime is important in the formation of 
teeth and bone, and when drinking water does not 
contain lime in excess, then it must be regarded as 
beneficial, especially so in early life, when the tissues 
are developing. 
On the other hand, lead is a very dangerous ingredi- 
ent of water. Water that has stood in lead pipes should 
never be used for drinking purposes. If it is neces- 
sary to use lead pipes, then the water should be kept 
running, or a large quantity drawn off before any is 
taken for use. There is no reason for supposing, sim- 
ply because water has no odor and looks clear, that it 
does not contain in solution substances of a most poi- 
sonous nature. 
Organic matter may be present in a state of de- 
composition. When there is any danger of this, it is 
much better to boil the water for a long time, and 
thereby destroy the minute germs. During an epi- 
demic of typhoid fever it is a wise precaution to drink 
no water that has not been so treated. When cool, 
after boiling, a little lime juice may be added to the 
water to correct the insipid taste, as the boiling drives 
off the carbonic acid gas. Do not use water that may 
be near some source of filth, and be sure that the well or 
spring is located at a safe distance from any decaying 
organic matter. 22 
THE ESSENTIALS OF HEALTH. 
While the system daily demands a large amount of 
water, yet too much is injurious, especially if taken 
with the meals. When the body is in a healthy condi- 
tion, the demand for water is easily satisfied. Re- 
member it is best to drink sparingly at mealtime, and 
more freely between meals. It is very unwise to use 
ice-cold water at any time, and it is especially bad to 
take it with a meal. 
There are other inorganic foods besides water and 
salt, — as the various chemical salts, such as the salts 
of soda, potassa, and lime. 
QUESTIONS. 
1. What relation do waste and repair bear to each other at dif- 
ferent periods of life ? 
2. Give some of the uses of foods. 
3. Name foods derived from each of the kingdoms. 
4. How are foods classified? 
5. Where is salt found in the body ? In what foods ? 
6. Give some of the uses of salt. 
7. What proportion of the body is composed of water ? 
8. Why is water so important ? 
9. What does rain water contain ? Spring water? 
10. Which form of life flourishes best in spring water ? 
11. From what source is drinking water usually obtained? 
12. Is a small amount of lime in drinking water beneficial ? Why ? 
13. How can the germs in water be destroyed ? THE NITROGENOUS FOODS. 
23 
CHAPTER III. 
THE NITROGENOUS FOODS. 
The organic foods, derived from the animal and 
vegetable kingdoms, are divided into twro classes, de- 
pending upon the presence or absence of nitrogen. 
They are called, therefore, the nitrogenous and the 
non-nitrogenous foods. 
The Nitrogenous Foods. The nitrogenous foods are 
also called the albuminoids, from their resemblance to 
albumen. They include such foods as the meats, eggs, 
and milk. Albumen, as found in the white of eggs, is 
in nearly a pure state. It forms the chief part of mus- 
cle, and is found in nearly all the fluids of the body, 
including the blood and lymph. As the albuminoid 
substances are so abundant, entering largely into the 
formation of the animal tissues and fluids, so their 
absence from food is soon felt. 
No diet can be nutritious, when long continued, un- 
less it contains some of these foods. The nitrogenous 
foods need not necessarily be from the animal king- 
dom, as the cereal grains contain nitrogen, but in these 
the relative quantity is much smaller. The nitrogenous 
foods are capable of sustaining life much longer than 24 
THE ESSENTIALS OF HEALTH. 
the foods consisting of starch, fat, or sugar. Yet even 
these foods, when taken alone, are not capable of sup- 
porting life. Animals that have been fed on such ex- 
clusive diet become enfeebled, refuse food, and finally 
die. Their continued use, by man, results in a great 
dislike for them, showing that other materials are neces- 
sary to supply all the demands of the system. 
It follows, therefore, that while the albuminous foods 
are the first in importance, yet we must not depend 
upon one kind of food to sustain life. Foods contain- 
ing starch and oil are as necessary as are the inorganic 
substances. The body must be supplied with the same 
variety of ingredients as that found in its tissues. To 
deprive it of any one of these will slowly but surely 
bring on disease and death. 
Milk. The “ model food ” is the name often given to 
milk; no ideal food can surpass it. As it contains all 
the food elements necessary for the support of the body, 
it will, therefore, support life longer than any other 
single article of diet. It contains a large amount of 
water, nearly nine parts in ten; a considerable amount 
of fat, as butter ; a sugar, known as milk sugar ; miner- 
als ; and albumen. The mineral matter consists largely 
of lime, so essential to the formation of the bones when 
they are growing rapidly. 
The nitrogenous matter consists almost entirely of 
albumen and caseine. If any acid be added to milk 
the caseine is thrown down in a coagulated form, and 
the milk is said to be curdled. The milk curdles spon- 
taneously if exposed to the air for a few hours and in 
a warm room. This is because of the development of 
lactic acid in the milk. The action is the same as if THE NITROGENOUS FOODS. 
25 
the acid were added intentionally, and the caseine thus 
coagulated. From this coagulated mass, or curd, cheese 
is made. The fat of milk consists of vast numbers of 
minute oil drops. These appear, under the microscope, 
as small round globules floating in water. 
Fig. 3. Milk, highly magnified. 
Milk readily absorbs gases ; therefore special care is 
required to keep it sweet and pure. It must be kept 
in a room that is very clean and free from all odors. 
Milk may be the means of communicating disease, either 
by the use of impure water with which the milk was 
adulterated, or by the milk having absorbed injurious 
gases. 
Milk should be the principal diet for children, while THE ESSENTIALS OF HEALTH. 
26 
for adults it may be used as a drink with the ordinary 
meals. Warm milk can take the place of the cup of 
coffee, while cool milk is a good substitute for ice water. 
Some people claim they cannot use milk, as it disagrees 
with the stomach and interferes with the action of the 
liver. These troubles are easily prevented by using only 
a moderate amount, and by adding to it a small quantity 
of lime water. 
Eggs. Eggs are easily digested and very nutritious. 
They are the most digestible when soft-boiled in the 
shell, or when broken into boiling water. The principal 
differences between the white and the yolk of the egg 
are these: the white contains no fat, but a considerable 
quantity of water; while the yolk contains a consider- 
able amount of fat, and but little water. Nearly thirty 
per cent of the yolk consists of this fat, or yellow oil. 
Meats. The meats used for food are rich in nitroge- 
nous ingredients, together with fat and mineral matter. 
Their nutritious properties and pleasant taste make 
them very desirable as articles of diet. The meats dif- 
fer in their digestibility, and in their nutritive value. 
Beef is regarded as the best meat for general use. 
When tender beef is properly cooked, it is easily digested 
and very nutritious. Mutton ranks next to beef, although 
its flavor is not agreeable to all. 
Yeal is not easily digested, neither is it so nourish- 
ing as either beef or mutton. Pork is not readily di- 
gested ; the fibers of the lean meat are too compact, and 
the fat is likely to be in excess. A large class of peo- 
ple, however, eat it freely. To those who exercise 
much, and who have strong digestive powers, pork ap- 
pears to do no harm. Oysters are very nourishing, are THE NITROGENOUS FOODS. 
27 
easily digested, and are very pleasant to those who have 
acquired a taste for them. Oysters are most easily 
digested when eaten raw, furnishing in this particular 
a striking exception to the general rule for all animal 
substances. 
The Cereal Grains. The cereal grains, as wheat, oats, 
corn, and rice, are most important foods. They consist 
of nitrogenous material, starch, sugar, salts, and fat. 
The starch is seen as the white center of the grain, 
surrounded by a husk. The husk consists of a wbody 
material and is quite indigestible. The nitrogenous por- 
tion of the grain is situated between the husk and the 
starchy center. Wheat flour would be much more nu- 
tritious if only the husk, or bran, were removed, and the 
layer containing the nitrogenous matter and the gluten, 
oil, and salts retained with the starch. The flour would 
not be so white, neither would the bread, but it would be 
more wholesome. The gluten, or the adhesive, jelly-like 
quality of the cereals, is very abundant in wheat, forming 
about twenty per cent of the whole grain. 
The grains vary in their proportions of nitrogen and 
starch; but their value as a food does not depend alone 
upon the amount they contain of any single nutritive 
ingredient. There should be such a variety of substances 
as will form the best combination for the nourishment 
of the body. 
Wheat leads all the cereals in nutritive value. It is 
easily digested and, with the exception of milk, it comes 
nearest to the standard of a perfect food. It contains 
but a small proportion of water; has a large amount of 
starch; is well supplied with nitrogenous material; con- 
tains fat; and considerable mineral matter. There is, 28 
THE ESSENTIALS OF HEALTH. 
however, a deficiency in the amount of fat it contains; 
therefore this must be supplied by putting butter on the 
bread. The proportion of water is so small that a given 
bulk of wheat is richer in solids than any other food. 
Probably the best test there is for a good wheat is the 
kind of bread it will make. 
Bread. Bread is often called the staff of life, because 
it contains so many nutritious elements, being deficient 
only in fat. Thus it follows that bread and butter 
make a very complete diet. In making bread the flour 
is mixed with water until a dough is formed. Then salt 
and yeast are added. This is set aside in a warm place 
until fermentation is well established. The nitrogenous 
ingredients begin to decompose and act as a ferment on 
the starch, which becomes, in part at least, changed to 
sugar. The sugar is further decomposed into carbonic 
acid and alcohol. 
The carbonic acid forms bubbles; these force their 
way through the dough, or sponge, making the bread 
rise. The dough is now placed in an oven hot enough 
to stop fermentation at once. The alcohol is all driven 
off by the heat, and much of the water also. The bread 
is then said to be baked. But yeast is not essential to 
the making of bread. Unfermented bread is made by 
mixing with the dough a powder composed of an acid 
and an alkali, so that after the powder is moistened in 
the bread the acid and alkali form a new compound, 
and carbonic acid is set free. 
In aerated bread the carbonic acid is forced into 
water, and the flour mixed with this water under pres- 
sure. When the dough is heated the carbonic acid ex- 
pands and makes the bread spongy. THE NITROGENOUS FOODS. 
29 
Bread made from unbolted flour is very nourishing, 
but the presence of the bran makes it difficult to digest, 
so that it should not be used by persons with weak 
digestive powers. Hot bread is likely to form a paste in 
the mouth, and thus its digestion becomes difficult. 
Oats, Corn, Rice. Oatmeal contains a large amount of 
nitrogenous material, ranking in this regard nearly or 
quite equal with wheat. But it contains a considerable 
amount of woody or fibrous material, which interferes 
with the digestion of it and lowers its nutritive value. 
It also lacks adhesive qualities, so that it cannot be 
made into bread. Yet it is a wholesome food, and to 
most persons agreeable. 
Corn contains less nitrogenous material than oats, 
but it has more starch. Rice consists of ninety per 
cent of starch with scarcely any nitrogenous material. 
When taken with some albuminous food, as meat of any 
kind, it is a valuable article of diet; it is easily digested 
and is also very cheap. Peas and beans are very nour- 
ishing, for they contain a good amount of albumen and 
starch. They would be valuable as food were it not that 
they consist of such solid matter that they are not easily 
digested. When used, they should be cooked a long 
time, and be thoroughly masticated. 
Potatoes consist of from seventy to eighty per cent of 
water; the remainder being nearly all starch, together 
with a small amount of mineral matter, albumen, and 
salts. Although they consist so largely of water, yet 
they are the most generally used of all vegetables. They 
are. used extensively because they can be obtained at all 
seasons of the year, are very cheap, and agree with most 
persons. They should never form the exclusive diet; 30 
THE ESSENTIALS OF HEALTH. 
but, when used with some fat, as butter or meat-gravy, 
and salt, together with some food rich in nitrogenous 
matter, they form a most valuable adjunct to the table. 
Turnips, cabbage, parsnips, onions, and other vegeta- 
bles, are added to the list of foods in order to give suit- 
able variety. Their nutritive value is low, and they are 
not easily digested. 
Apples, peaches, pears, and other fruits are valua- 
ble foods in many ways. They contain a considerable 
amount of sugar and mineral matter, while their acids 
give them a characteristic taste. These acids stimulate 
the appetite and promote the flow of gastric juice, while 
the great amount of water they contain serves to quench 
the thirst. Ripe fruits in their season are most bene- 
ficial ; while overripe and unripe fruits are often the 
cause of serious trouble. Much of the danger, however, 
of unripe fruits is removed by cooking. 
QUESTIONS. 
1. How are the foods from the animal and vegetable kingdoms 
divided ? 
2. The nitrogenous foods include what ? 
3. Where is albumen found ? 
4. What is said about supporting life with one kind of food ? 
5. Of what is milk composed ? 
6. Is beef nutritious and easily digested? Is mutton? Veal? 
Pork ? Are oysters ? 
7. Of what do the cereal grains consist ? 
8. Which is the most nutritive of the cereals? 
9. In what is it deficient ? How is this supplied ? 
10. Why is bread a valuable food ? 
11. What cereal ranks next to wheat? 
12. What is said about potatoes as a food? THE NON-NITROGENOUS FOODS. 
31 
CHAPTER IV. 
THE NON-NITROGENOUS FOODS. 
COOKING. 
Fats. The non-nitrogenous foods consist of starch, 
sugar, and the fats. There is a natural craving in the 
system for these foods, and they cannot be dispensed 
with for any great length of time without serious injury 
to the system. 
Experiments have proved that some fat must enter 
into the diet if the bodily health be maintained. This 
seems to be especially true when the body is growing 
rapidly. Some individuals do not digest the fat of 
meats readily, yet they can use butter and milk. Oth- 
ers are able to digest such fatty foods as bacon or 
the fat of other meats. Fat has great heat-producing 
power, therefore it is most used where the climate is 
cold and severe. 
It is probable that some of the fat in the body is 
derived directly from the fat of the food; that is, it 
becomes absorbed and redeposited in the tissues; but 
it is equally true that fat may be formed in the body 
from foods which are without fat. This is proved to 
be a fact, because the amount of fat, or butter, found 
in the milk of the cow far exceeds the amount of fat 
taken as food. THE ESSENTIALS OF HEALTH. 
32 
Some persons become very fleshy, while others, with 
the same diet, remain lean. In many families there is 
an inherited tendency to accumulate fat in the body. 
It is probable also that, in some cases at least, more 
food is taken than is necessary for the normal uses of 
the body. A deposit of too much fat is attended with 
inconvenience and no little danger. 
Starch. Pure starch is a fine, white powder, consisting 
of minute granules. When examined under the micro- 
scope, the granules are seen to vary in size and form, ac- 
Fig. 4. Wheat starch, or wheat flour, highly magnified. 
cording to the kind of starch. Thus it becomes possible 
to tell from what vegetable the starch was obtained by the 
appearance of the granules. The four illustrations here 
given show these marked differences. Each starch is 
magnified the same number of times, or about five hun- 
dred diameters. The granules are very minute, those of THE NON-NITROGENOUS FOODS. 
33 
rice starch being not over g of an inch in diameter. 
A study of the starches is very fascinating work to 
those who have a microscope. When mixed with water 
the granules swell and form a paste; when boiled with 
a large amount of water they expand greatly, and can 
Fig. 5. Oat starch, highly magnified. 
no longer be seen. The destruction of these granules 
is a great aid to their digestion. Prolonged cooking 
changes the starch into a substance called dextrine. 
This is easily changed by the digestive juices into glu- 
cose or grape sugar. The brown crust of the bread is 
the starch of the flour, changed into dextrine by the 
prolonged exposure to beat. It is more easily digested 34 
THE ESSENTIALS OF HEALTH. 
than the softer parts of the bread. In order that the 
starch granules may be completely broken up, all starchy 
foods should be thoroughly cooked. A too exclusive 
Fig. 6. Corn starch, highly magnified 
Fig. 7. Potato starch, highly magnified. 
diet of starchy foods is likely to impair the digestive 
powers; for the digestive juices are unable to promptly THE NON-NITROGENOUS FOODS. 
35 
change large quantities of starch into sugar, and the 
sugar is slowly absorbed if present in too large quan- 
tities. This gives rise to the formation of gases and 
acids, and then dyspepsia follows. 
Sugar. Sugar is closely allied to starch, both in its 
chemical and physiological relations. In the living- 
plant the sugar and the starch represent the same nu- 
tritive material, though under different conditions; the 
sugar is in the form of a liquid, and the starch is in the 
form of a solid. 
There are three principal varieties of sugar, — cane 
sugar, grape sugar, and milk sugar. Cane sugar is that 
obtained from the juice of the sugar cane. It is the 
variety in ordinary use. It is also made from the juice 
of the maple tree, and is called maple sugar. It is the 
most soluble and the sweetest of the sugars. Grape 
sugar is found in great abundance in the juice of ripe 
grapes. It is generally distributed in the sweet juices 
of many fruits and flowers. This is the reason it is 
found in honey, although cane sugar is also present. 
Grape sugar, also called glucose, is found in some of the 
animal tissues and fluids, as in the liver and the blood. 
This is the form of sugar which is made in the body by 
the digestion of starch. The third variety, the sugar 
of milk, is found only in milk. Its sweet taste is not 
very marked. 
While it is true that a considerable quantity of sugar 
is likely to disturb the stomach, yet it is equally true 
that a certain amount is very desirable. The natural 
desire for sweet things is so universal in the young 
that it can indicate nothing else than a demand of the 
system for this food. The impure and highly colored 36 
THE ESSENTIALS OF HEALTH. 
candies in the store do not represent a definite amount 
of sweet food. It is better to satisfy the craving by 
eating ripe fruit. But if candies are desired, let them 
be made at home, from pure sugar. There is no danger 
of the teeth being injured by the use of sweet foods, 
if they be cleansed each day, as they should be under 
all circumstances. 
The Amount and Kind of Food. No rule can be laid 
down saying positively just how much of each kind of 
food must be taken; but if the body be in a healthy 
condition, an amount should be taken sufficient to sat- 
isfy the appetite. The appetite, however, is not always 
a safe guide, because by irregular habits, by overeating, 
and by eating improper articles of food, it becomes vari- 
able, and is then an unreliable test. Persons are liable 
to eat too much at a time when some particular article 
of diet is especially pleasing, and in this way weaken 
the digestive functions. 
•The quantity of food must vary with the amount and 
kind of exercise. A good rule is this : Learn what are 
wholesome foods, how they should be cooked, and that 
a mixed diet is best; then decide what and how much 
to eat. Some persons require only a small amount of 
food to keep them in good health, while others require 
much more. Yet sickness is caused by overeating, as 
well as by eating things which are harmful. Habit and 
custom have a great deal to do with determining the 
kind and amount of food. 
Cooking is absolutely necessary for some kinds of 
food, in order that they may be properly digested. It 
either softens the food or aids in dividing it into small 
particles. It also brings out distinct and agreeable fla- COOKING. 
37 
vors, and thus pleases the taste. If the temperature 
employed in the cooking be too high, the natural flavors 
will be destroyed, and disagreeable odors will be pro- 
duced ; while if the temperature be too low, the flavors 
are not developed. 
Cooking coagulates the albumen in the foods : it ren- 
ders the fatty tissues more fluid ; it changes the starchy 
foods into a pulpy mass, and it breaks up the harder 
tissues of the vegetables. Thus the foods are softened, 
and are more easily masticated. 
Methods of Cooking. Nearly all the articles of food 
are cooked before eating, the principal exceptions being 
oysters and certain ripe fruits. 
In broiling, roasting, or boiling meat it is desirable 
to retain in the meat as much of the nutritive properties 
as possible. This can be done by applying great heat 
at first, producing a rapid coagulation of the albumen 
on the surface. This forms a crust, through which the 
nutritive juices of the meat cannot escape. Afterwards 
the cooking should proceed with a less degree of heat, 
until the meat is cooked to please the taste. 
When meats are cooked too thoroughly their natural 
juices are driven off by the prolonged heat, and their 
albuminous matter is hard and dry. Such meats are 
masticated with difficulty and digested slowly, while 
much that is nutritious is lost. The only argument 
advanced in favor of such thorough cooking of meat 
is that it destroys all parasites; but there is little 
if any danger of these in any of the meats, if pork be 
discarded. 
Broiling is the best method of cooking meat, while 
roasting is nearly as good. Vegetables and the coarser 38 
THE ESSENTIALS OF HEALTH. 
meats can be made very tender by prolonged boiling, 
remembering that they should be placed at once into 
boiling water, when after the first application of heat 
the temperature should be considerably lowered. Even 
potatoes would be more nutritious if boiled with at least 
a portion of their skins on, as the skins would aid in 
retaining some of the nutritious materials that would 
otherwise be lost. 
Frying is about the worst of all the methods of pre- 
paring meats and other foods for the table. The fat in 
the meats, or the fat in the frying-pan, penetrates the 
lean portions and surrounds each particle with a layer of 
oil. As oil is not digested in the stomach, it follows 
that the meat with its oily covering must pass out of 
the stomach before the outer coat of oil can be com- 
pletely removed. Certain fatty acids are also developed 
during the frying process which are likely to prove inju- 
rious. If food must be fried, the fat should be boiling 
hot when the articles are put into it, and it should be 
kept boiling during the entire cooking. Thus by form- 
ing a hard outer coat at once, the fat is not so likely to 
penetrate deeply. 
In making soups it is desirable that all the juices be 
extracted from the meat, — a result just the opposite of 
the one desired in broiling or roasting. Therefore the 
meat should be cut into small pieces and placed in cold 
water at first, and the water gradually allowed to come 
to a high temperature. In this way no layer of coagu- 
lated albumen is formed on the outside, and all the 
juices are gradually brought out by the water. 
Enough has been said to show that healthy, whole- 
some cooking depends upon well-known laws of chemis- COOKING. 
39 
try and physiology. A knowledge of these sciences is 
necessary to fully understand and master the mysteries 
of this art. But it is one of the happy circumstances of 
early life that if there is a healthy body to begin with, 
it does not become necessary to study the articles of 
food as they are placed on the table. We eat heartily 
of the good things provided for us; enter into all the 
labors and pleasures of the day with much earnestness; 
sleep soundly at night; awake in the morning with 
rested body and clear brain; and begin again a new 
day. Thus should it be all through life. 
QUESTIONS.1 
1. What are the non-nitrogenous foods? 
2. Are these foods necessary ? 
3. What especial power has fat ? 
4. The fat of the body is derived from what? 
5. Give a description of starch. 
6. What is said of the different forms of starch grains ? 
7. How does cooking affect starch ? 
8. What non-nitrogenous food is closely allied to starch ? 
9. Name the varieties of sugar. 
10. Where is cane sugar obtained ? 
11. Where is grape sugar found ? 
12. How does cooking affect the food ? 
13. What is desirable in broiling meats? 
14. How can this be accomplished ? 
15. Why is frying a poor method of cooking meats ? 
16. How can all the juices be extracted from meat ? 40 
THE ESSENTIALS OF HEALTH. 
CHAPTER V. 
ALCOHOL. 
The microscope of modern times reveals to us many 
wonderful things. It shows the existence of the most 
minute forms of living objects ; so minute that the high- 
est powers of the microscope and the greatest skill of 
the observer are necessary to see them. These forms 
are so minute that they are often spoken of as “ micro- 
organisms.” The germs or spores of these micro- 
organisms float about in the air in a dry state, and are 
carried with the dust and deposited upon objects every- 
where. 
Whenever any dead animal or vegetable substance is 
left in a moist state in moderately warm air, these 
minute forms enter it and begin at once to take it to 
pieces. It has been conclusively proven that no putre- 
faction or decay ever occurs without the presence of 
some of these micro-organisms, and that they are the 
cause of such decay. To illustrate the power which they 
have, it is only necessary to notice any dead animal or 
vegetable substance. When left to itself such material 
gradually changes its appearance, becomes softer, the 
liquids evaporate, the gases escape, and only a little 
earthy matter is left. This is all the work of these ALCOHOL. 
41 
microscopic objects. They have succeeded in completely 
changing the character of the animal or vegetable 
substance. 
Let us experiment something like this: Boil a piece 
of meat in some water and then strain the mixture, so 
that only a clear liquid or infusion remains. Now if 
this clear solution be boiled and placed in a bottle while 
at the boiling point, and the bottle tightly sealed, the 
solution will remain clear indefinitely. A similar result 
is shown in the canning of fruits; the boiling fruit is 
placed in cans, whicli are at once tightly sealed. Why 
do not these canned fruits decompose ? Because the 
heat applied to them destroys all the micro-organisms, 
and because no others can gain entrance through the 
tightly sealed vessels. 
Suppose, however, that we open the can of fruit or 
the bottle of meat infusion. In a few days the liquid 
will become cloudy, a scum will gather on the surface, 
and a disagreeable odor will be given off. What is the 
cause of these changes ? Micro-organisms have entered 
and decomposition is taking place. It is not necessary 
to add these minute objects to dead substances in order 
that they decay. The germs or spores that cause decay, 
as has been stated, float about in the air, though invisi- 
ble. In fact they are distributed almost everywhere 
throughout nature. 
There are many varieties of these minute organisms, 
each of which takes its food from a different kind of 
dead substance, and in so doing, causes that substance to 
decay or go to pieces. Some of these micro-organisms 
are called “ bacteria/’ from a Greek word signifying 
staff or rod., They are so named from their resem- 42 
THE ESSENTIALS OF HEALTH. 
blance, as seen through a microscope, to minute staves 
or rods. Other organisms are known as ferments. 
Still other organisms are called molds. 
Whenever a dead substance is acted upon by these 
micro-organisms a change takes place which is called 
fermentation. During this change the elements which 
compose the fermenting substance are separated. These 
elements, thus set free, enter into other combinations, 
forming new substances. The first substance may be 
very simple and wholesome; but after the elements, as 
carbon, hydrogen, nitrogen, and oxygen, have been sep- 
arated by the process of fermentation, they may unite 
again in a very different manner, producing a highly 
poisonous compound. 
To illustrate this, let us take sugar, which is com- 
posed of carbon, hydrogen, and oxygen, combined in a 
certain exact proportion, and dissolve it in the right 
amount of water, and add some ferment, as yeast. This 
ferment, which cannot work on dry sugar, causes the 
union of the carbon, hydrogen, and oxygen to break to 
pieces and new compounds to be formed. Some of the 
carbon and oxygen unite to form carbonic acid gas which 
escapes in bubbles ; while the remaining carbon and oxy- 
gen, and all the hydrogen are left so united that a liquid 
is formed which is called alcohol. Alcohol, therefore, 
is a result of one kind of fermentation. 
There are many kinds of fermentation. For instance, 
when meat decays, the process is called putrefactive fer- 
mentation ; it is caused by a certain species of bacteria 
which do not thrive upon preserves, or other substances 
not adapted to their growth. The souring of milk is 
called lactic fermentation; it is caused by>another spe- ALCOHOL. 
43 
cies of bacteria, which changes the sugar of the milk to 
lactic acid. 
The decay of fruits is also caused by micro-organisms, 
many of which we are familiar with in the form of 
molds. The microscope shows that these molds are 
minute plants, the spores or germs of which are float- 
ing everywhere in the air. 
The spores of other micro-organisms called ferments 
float in the air, and fall upon the surface of fruits. With 
them are also the spores of ferments, which are also 
plants. But between the sweet juices of the fruits, and 
the ferments there is a sound and complete membrane 
which we call the skin. While the juice remains in the 
fruits, the ferments can do no harm. They are harmless 
if taken as we eat the fruit; but when the juices are 
pressed from the fruits, these ferments, lodged on the 
surface, are washed into the liquid. If this mixture be 
allowed to remain in a moderately warm atmosphere, 
the spores of the ferments soon begin to grow and 
multiply with great rapidity. 
We know that ripe fruits contain more or less sugar 
dissolved in the water or juice of the fruit. As we have 
already seen, the ferments begin at once to take oxygen 
from the sugar, causing the sugar to break to pieces, and 
to form two new substances, — carbonic acid gas which 
escapes in bubbles, and alcohol which remains. 
Alcohol is the product of this process of fermentation. 
Although sugar and water are such harmless foods, yet 
by the action of the minute ferments, a narcotic poison 
is obtained from them. Alcohol is called a narcotic 
poison because of its power to deaden or paralyze the 
brain and nerves. Like opium, tobacco, and other nar- 44 
THE ESSENTIALS OF HEALTH. 
« 
cotics, its chief danger lies in its power to set up a 
continual and ever-increasing demand for itself. It is 
more dangerous, therefore, than some other poisons, 
which, taken in quantities too small to cause death, 
may pass off without doing appreciable injury. 
From what has been said, it is evident that alcohol is 
not a natural part of fruits or grains. With these facts 
in mind it is easy to understand why beer, wine, and cider 
are poisonous liquors, although obtained from whole- 
some fruits and grains. For we must remember that it 
is a law pervading nature that fermentation entirely 
changes the character of the substance it works upon. 
It is another illustration of this law that the fruit juices 
which have undergone alcoholic fermentation will, if left 
to themselves in warm air, be entered by another kind 
of ferment which changes the alcohol to acetic acid. 
This change, which is called acetous fermentation, is the 
one that turns cider to vinegar. 
Cider. The juice of apples when first pressed from 
the fruit, consists simply of water, more or less sugar, 
and a small amount of acid. Thus, in ordinary cider- 
making, the proper conditions are present for alcoholic 
fermentation to take place. These conditions are: water, 
sugar, warm air, and the ever present ferment germs 
which float in the air, and those which were washed 
from the surface of the fruit while it was being ground 
and pressed. Thus it follows that within a few hours 
after the juice has been pressed from the apples the 
process of fermentation is well under way. 
When obtained from the mill all fresh cider is ordi- 
narily more or less contaminated with the fermented 
juices which remained in the mill or vats from the pre- ALCOHOL. 
45 
vious grinding. It is therefore difficult to obtain cider, 
even directly from the mill, which does not contain more 
or less alcohol. Certainly there is no sharp line between 
sweet and sour cider. If cider does not contain alcohol 
it is harmless ; if it does, it is injurious. 
As nearly all so-called “ sweet cider ” may contain 
more or less alcohol, and as alcohol even in small quan- 
tities has the power to create an appetite for more, and 
as the delicate tissues of the human system are easily im- 
pressed, the testimony of science is strongly against the 
use of cider in any quantity. It is certainly true that the 
continuous drinking of old cider makes the person irrita- 
ble, blunts the finer sensibilities, and weakens the will. 
Wine. When the juice is pressed from the grape, the 
currant, or the elderberry, the ferments on the surfaces 
of these fruits are carried into the juice and there begin 
to change the sugar of the juice as in the case of cider. 
If a small amount of sugar be added to the juice there 
is then so much more material on hand to be converted 
into alcohol. For this reason it is true that homemade 
wines often contain more alcohol than the wines of com- 
merce. Homemade wines may be “ pure ” as to their 
freedom from adulteration by drugs, yet the one great 
poison, alcohol, is present; and for this reason they are 
pernicious. 
Wine is the earliest known and most extensively used 
of the alcoholic liquors. Its occasional or moderate use 
is never safe, although it has been so considered by those 
who were ignorant of the power a little wine has to 
create an appetite for more. No one can tell how soon 
such an appetite may be formed, nor how soon it may 
become an uncontrollable craving, to gratify which is to 46 
THE ESSENTIALS OF HEALTH. 
invite destruction. Ignorance of these facts, or a mis- 
taken confidence in this beverage, has not prevented the 
evil results that follow its use. 
The notion is quite prevalent in many sections of the 
country that a greater abundance of “ light wines ” would 
prevent the use of stronger liquors, and thus diminish 
intemperance. But the steady growth of intemperance, 
with its attendant evils of immorality, insanity, and other 
nervous diseases, in wine-growing countries, where light 
wines are cheap, plentiful, and universally used, proves 
the fallacy of this idea. 
A recent alcoholic commission, appointed by the 
French Minister of Finance, reported that alcoholism 
threatens the people of France with rapid degenera- 
tion ; that it is one of the most serious dangers of the 
times. Not only men but women and children are 
affected. Mental diseases hitherto unknown have be- 
come common. 
Dr. J. G. Holland, after spending some time in Swit- 
zerland, gave the following testimony as to the effects of 
light wines there : — 
“ We have been told in America, and I fully believed it, 
that if a people could be supplied with cheap wine, they 
would not get drunk, — that the natural desire for some 
sort of a stimulant would be gratified in a way that would 
not only be harmless to morals, but conducive to health. 
I am thoroughly undeceived. The people drink their cheap 
wine here to drunkenness. A boozier set than hang around 
the multitudinous cafes here it would be hard to find in 
any American city. 
“ The steady old white-wine topers come into blossom. 
If you can image a cauliflower of the color of the ordinary ALCOHOL. 
47 
red cabbage you can achieve a very adequate conception of 
faces that are not uncommon in all this wine-growing 
region. So this question is settled in my mind. Cheap 
wine is not the cure for intemperance. The people here 
are just as intemperate as they are in America, and what is 
more, there is no public sentiment that checks intemper- 
ance in the least. The wine is fed freely to children, and 
by all classes is regarded as a perfectly legitimate drink. 
“ I firmly believe that the wines of Switzerland are of 
no use, except to keep out whiskey, and that the advan- 
tages of wine over whiskey are not very obvious. It is 
the testimony of the best people of Switzerland — those 
who have the highest good of the people at heart — that 
the increased growth of the grape has been steadily and 
correspondingly attended by the increase of drunkenness. 
They lament the planting of a new vineyard as we at 
home regret the opening of a new grog-shop. They expect 
no good of it to anybody. They know and deeply feel 
that the whole wine-growing enterprise is charged with 
degradation for their country.” 
Beer. Although beer is made from grain which con- 
sists principally of starch, this starch is readily changed 
to sugar in the process of growing and sprouting. It is 
only necessary to dissolve out the sugar from grains 
which have sprouted in order to have a sweet liquid; and 
this will produce alcohol if the right kind of ferments 
are added. Therefore, to this sweet liquid, yeast, which 
is an alcoholic ferment, is added. The ferments, or 
yeast, begin at once to work upon the sugar, taking 
oxygen from it and leaving carbonic acid gas and alco- 
hol. The former bubbles up through the liquid and 
passes into the air; while the latter stays in the beer. 
Hops also are added, which give the beer a bitter taste. 48 
TIIE ESSENTIALS OF HEALTH. 
The food value of grain is almost entirely lost in this 
fermenting process, while the resulting alcohol has its 
ever present power to injure and degrade the drinker. 
Beer so undermines the physical system that beer- 
drinkers are peculiarly susceptible to disease, and have 
weakened powers of recovery. A celebrated physician 
says : “ The diseases of beer-drinkers are always of a 
dangerous character, and in case of an accident they 
can never undergo the most trifling operation with the 
security of the temperate.” 
Distillation. In such mixtures as cider or wine, the 
alcohol forms only a certain per cent of the whole 
liquid. To separate the alcohol from the other ingredi- 
ents it is only necessary to take advantage of the fact 
that some liquids evaporate much more easily than 
others. We already know that alcohol is driven off by 
a low degree of heat, even before the water in the mix- 
ture is warm enough to boil. Therefore, if a ce7’tain 
degree of heat be applied to wine, the alcohol will 
be expelled, as a vapor, before much of the water is 
given off. Some water, however, escapes with the 
alcohol, together with some aromatic substances. This 
is brandy, which consists of about fifty per cent, or 
one half, alcohol. 
Brandy is also distilled from the fermented juice of 
many other fruits. Whiskey is distilled from the fer- 
mented grains. In Ireland it was formerly called by a 
very characteristic name, the translation of which gives 
“ madness of the head.” 
Understanding the principle of fermentation and dis- 
tillation, it is easily seen how a large number of highly 
intoxicating drinks can be obtained from a great variety ALCOHOL. 
49 
of sources. For instance, by steeping roots of plants or 
trees, thus extracting their flavor, and adding sugar and 
yeast, it becomes an easy matter to obtain a product of 
fermentation. Some of these are called homemade beers. 
The fact that they contain alcohol is their condemnation. 
By distillation the alcohol and aromatic qualities can 
be separated, and powerful drinks obtained. In all 
parts of the world large numbers of intoxicating drinks 
are obtained in this way, from sweet grasses, from 
roots, and from nearly all kinds of fruits and grains. 
That evil results follow their use in all lands is odvi- 
ous to even the casual observer. 
1. What does the microscope reveal ? 
2. How do these micro-organisms affect dead animal and vege- 
table matter ? 
3. What is necessary for decay ? 
4. flow can we illustrate the power of these micro-organisms ? 
5. Describe the experiment of boiling meat in water. 
6. Why do not canned fruits decompose ? 
7. Where are the spores or germs found? 
8. Name some of the varieties of these micro-organisms. 
9. How does fermentation affect a substance ? 
10. How is alcohol made from sugar, water, and yeast? 
11. Give illustrations of some of the fermentations. 
12. How do molds cause fruit to decay ? 
13. Why is alcohol called a narcotic poison? 
14. Why is it dangerous ? 
15. What is said of the fresh juice from fruit ? 
16. Why is there likely to be alcohol in so-called sweet cider? 
17. Why are homemade wines and pure wines not harmless ? 
18. How does beer affect the system ? 
19. What are some of the distilled liquors? 
20. How are they obtained from cider or wine ? 
QUESTIONS. 50 
THE ESSENTIALS OF HEALTH. 
CHAPTER VI. 
ADDITIONAL FACTS ABOUT ALCOHOL. 
It Creates an Appetite. There are only a few sub- 
stances which have the power to create an uncontrol- 
lable appetite for themselves. The most marked of these 
are, opium, tobacco, Indian hemp, and alcohol. The 
peculiarity of these drugs is that when once used there 
is a strong, almost irresistible desire to use them again. 
The amount of alcohol in cider, beer, or ale, is sufficient 
to create this desire. A few glasses of wine will make 
such an impression on some people that a strong desire 
for more of the stimulating effect is established. This 
is due entirely to the presence of alcohol. One drink 
creates a desire for another, until, as the system be- 
comes more and more under the influence of the alco- 
hol, the desire becomes greater and greater. A small 
quantity no longer satisfies, and the amount is gradually 
but steadily increased. Often the entire body is ren- 
dered stupid or insensible by the effort to satisfy the 
demands of this powerful appetite. 
In some instances a very little is sufficient to arouse 
a desire for drink of which the person was wholly un- 
conscious, while another person may take many glasses ADDITIONAL FACTS ABOUT ALCOHOL. 
51 
before he is aware that he has acquired a fondness for 
it. One of the weighty charges science lias to bring 
against alcohol is, that it has the power to create an 
ever-increasing appetite for its use. We know of only 
one way to escape this power: avoid all drinks which 
contain the smallest quantity of alcohol. 
Brandy sauce or wine jelly may seem like very inno- 
cent dishes, yet they may be the first step toward 
creating this appetite. This statement does not come 
from the imagination of the writer; it is based upon 
the scientific fact that alcohol has the power to create 
an appetite for itself, and that this appetite increases 
as the years go by. It is also based on the testimony 
of hundreds of people. 
The Appetite may be Inherited. It is generally accepted 
that the continued use of alcoholic beverages, for a con- 
siderable period of time, produces marked changes in 
the whole system. These will be brought out as we 
study the various organs and tissues. It is safe to 
assert, therefore, that alcohol produces a disease, known 
as acute or chronic alcoholism, and also that this disease 
may cause changes in certain organs and tissues. 
Now, we know there are some diseases which are he- 
reditary. We can even go farther than this and state 
that certain peculiarities and irregularities, the so-called 
minor ailments, are also hereditary. For instance, in 
families who have a “ nervous history ” there are an 
unusual number of headaches, attacks of indigestion, 
sleeplessness, and neuralgia. Certain families, for a 
number of generations, exhibit peculiarities of tem- 
per, likes and dislikes, fondness for certain kinds of 
work, etc., which are doubtless inherited. 52 
THE ESSENTIALS OF HEALTH. 
The various forms of insanity are striking examples 
of the power of disease to descend from one generation 
to another. There is nothing strange or unusual, there- 
fore, in the fact that the love of strong drink may de- 
scend from one generation to another. 
Not only is the liking for alcoholic liquors a legacy 
which the drinker’s innocent children often inherit, but 
the irritability of temper, the lack of energy, the weak- 
ened will, the untruthfulness, and the propensities to 
crime which the confirmed drinker brings upon him- 
self, these also may be an inheritance passed on to his 
children. 
It is a Poison. There are some people who claim that 
alcohol should not be called a poison. What is a poi- 
son ? Webster says a poison is “any substance which 
when introduced into the animal organism is capable of 
producing a morbid, noxious, or deadly effect upon it.” 
Let us study this definition more carefully, and obtain 
the full meaning of the three qualifying adjectives. 
Webster defines them as follows: “morbid,” not sound 
and healthful; “ noxious,” hurtful, harmful, injurious ; 
“ deadly,” capable of causing death, fatal. 
Jndged b)r such analysis, there can be no hesitation in 
classing alcohol with the poisons. But more than this ; 
in a work before us entitled, “ Poisons and Their Anti- 
dotes,” we notice that one of the poisons given is “ alco- 
hol, including brandy, wine, and all spirituous liquors.” 
In addition to this we have the testimony of a large 
number of noted physicians, chemists, and men of wide 
experience and learning, all testifying that “ alcohol is a 
powerful poison.” 
It Shortens Life. The fact that total abstinence low- ADDITIONAL FACTS ABOUT ALCOHOL. 
53 
ers the death rate was first shown by a Mr. Neison, 
of England. He based his conclusions upon statistics 
which he had been collecting for many years. His fig- 
ures showed that total abstinence tended to lengthen the 
probable life of mankind over twelve years. 
For many years a large life insurance company kept 
a separate account of the death rate among the total 
abstainers. They lately reported that the deaths have 
been 29 per cent less than among the others insured. 
Another company asserts that the death rate among total 
abstainers is from 80 to 40 per cent less than among 
those not so classed. Then, too, we have the combined 
statement of twelve presidents of life insurance com- 
panies, that “ alcohol tends greatly to shorten life.” 
We must not be confused by noting an occasional ex- 
ception to this rule. The physiological effects of the 
continued use of alcohol are such that there can be but 
one general result, — a weakening of all the powers of 
man, lowering his ability to withstand disease, produc- 
ing disease itself, and thereby shortening his days. 
It is a Source of Crime. In England, commissions 
have carefully investigated and reported the effects of 
the liquor traffic on the morals of men; in our country, 
eminent judges, who have extensive experience in the 
trial of criminals and in the investigation of crime, add 
their testimony; the “ London Times ” and eminent 
journals in our own country give the results of special 
investigations; and the keepers of various prisons send 
in their reports. From such source of information we 
learn that four fifths of all the crimes committed in this 
country are caused, directly or indirectly, by the use of 
alcoholic drinks. 54 
THE ESSENTIALS OF HEALTH. 
It is a Cause of Poverty. From such sources as the 
above, and from official reports of various State, munici- 
pal, and charitable organizations, we learn that fully 
one half of all the taxes paid by the people is required 
for the support of institutions made necessary by the use 
of alcoholic drinks. It is estimated that over half a mil- 
lion of persons are so affected, mentally and physically, 
by the use of alcohol that they are actually unable to 
labor, or attend to their business. These same authori- 
ties tell us that strong drink is the cause of three fourths 
of the pauperism in this country. 
It is Dangerous in Small Quantities. One of the argu- 
ments used in favor of drinking beer is this : the amount 
of alcohol in the beer is so small that no harm follows 
its use. On this point Dr. S. H. Burgen says : “ I think 
beer kills quicker than any other kind of liquor. My 
attention was first called to its effects when I began 
examining for a life insurance company. I passed as 
unusually good risks five men, who seemed in the best of 
health, and to have superb constitutions. In a few years 
I was surprised to see them drop off, with what ought 
to have been mild and easily curable attacks of disease. 
Beer had greatly reduced their power to resist disease.” 
Dr. S. S. Thorn testifies as follows : “ Adulterants are 
not, in my estimation, the important thing; it is the 
beer itself. Beer accumulates and gathers certain per- 
nicious agencies in the system, until they become de- 
structive. Every man who drinks beer begins to load 
himself with soft, unhealthy fat.” 
Dr. Parmelee says: “ The majority of beer-drinkers 
die from dropsy, arising from liver and kidney diseases, 
a direct result of their habits of life,” ADDITIONAL FACTS ABOUT ALCOHOL. 
55 
The president of a large life insurance company says: 
“ Beer-drinking in every case is peculiarly deceptive at 
first, and thoroughly destructive at last.” 
It is not a Food. We have shown that “alcohol and 
all spirituous liquors ” are poisonous. For this reason 
alone, we should not expect to find them valuable for 
food. Indeed, there is nothing about alcohol that gives 
us any idea it has food value. It cannot build up any of 
the tissues of the body, while it is often the cause of 
their breaking down. It contains no albuminous, starchy, 
or mineral ingredients; while the water existing in the 
alcoholic beverages can be obtained much purer else- 
where. Then again, close observation of its effects on 
man does not warrant us in believing that it has any 
value whatever as a food. 
This latter statement might not seem true, at first 
sight, in the case of beer; for heavy beer-drinkers are 
very likely to be fleshy. But what is the true condition 
of such, a body ? Certainly not one of health. For, 
while the fat is being deposited beneath the skin so that 
the whole body looks plump and well kept, the fat is also 
being deposited in the deeper parts of the body. 
In the muscular tissue of the heart and in the cells 
of the liver this unhealthy accumulation of fat is also 
deposited. The heart is thereby greatly weakened, so 
that it cannot do its work well. This causes poor circu- 
lation, shortness of breath, and often sudden death. 
The liver cannot perform its full work, and the usual 
results of such trouble follow. The blood vessels be- 
come weakened from a deposit of fat in their walls, 
making them much more liable to rupture in the brain, 
causing death from apoplexy. Then, too, the whole 56 
THE ESSENTIALS OF HEALTH. 
muscular system becomes greatly weakened; and at the 
same time all the more important organs and tissues in 
the body lose their proper structure and become more or 
less changed into fat. Any agent which is capable of 
bringing about such changes in the system has no place 
in the list of foods. 
Alcohol in whatever quantity or form taken, never 
aids in the building up of muscle, while its tendency is 
to destroy ; it never furnishes nourishment to the brain, 
but tends to weaken and dethrone the reason; it never 
relieves the heart of any work, but often so weakens it 
that the work is accomplished with great difficulty. 
QUESTIONS. 
1. What substances have the power to create an appetite for 
themselves ? 
2. What is a peculiarity of these drugs? 
3. Is a large amount of alcohol necessary to arouse this desire ? 
*4. What is one of the strongest charges against alcohol ? 
5. How can we escape this power ? 
6. The continued use of alcoholic beverages produces what ? 
7. What disease is produced by alcohol ? 
8. What is said about hereditary diseases? 
9. May the desire for alcoholic liquors be hereditary ? 
10. What proof have we that alcohol is a poison ? 
11. How does alcohol affect the length of life? 
12. Does it cause crime ? Poverty ? 
13. Are large quantities necessary for it to do harm ? 
14. What is said of alcohol as a food ? 
15. Repeat the eight sub-heads in this chapter, — the eight 
charges against alcohol. DIGESTLON. 
57 
CHAPTER VII. 
DIGESTION. 
Digestion. The substances necessary for the growth 
of vegetables, as a rule, are taken directly from the soil 
without change. The vegetables take their food as they 
find it. The materials which are suitable for the growth 
of the plant are found at its roots in such a condition 
that no marked alteration is necessary before they can 
be absorbed. At least, this appears to be the general 
rule. But with man this rule does not apply. 
Little of our food comes from the inorganic world. 
It was once organized, and formed a part of the ani- 
mal and vegetable kingdoms. As a rule, man does 
not take his food as he finds it. It has to pass 
through a series of changes before it becomes ab- 
sorbed into his system. The meats, fruits, and veg- 
etables are taken into the stomach in a solid and 
insoluble condition. The object of digestion, therefore, 
is to dissolve and change the food in order that it 
may be absorbed. 
Digestive Fluids must Vary. As the food consists of 
a variety of substances, with different physical and 
chemical properties, so there are several digestive fluids, 
each having its own particular effect. These juices are 58 
THE ESSENTIALS OF HEALTH. 
derived from minute glands, situated in the lining mem- 
brane of the alimentary canal, and from a few larger 
glands lying near this canal, with ducts leading directly 
into it. As the food passes down the alimentary canal, 
it comes in contact with these juices, and portions of it 
become liquified, in which condition it can be taken up 
by the absorbent vessels. 
Digestive Apparatus in Different Animals. It is very 
interesting to study the variety of arrangements of the 
digestive apparatus in the lower animals. As the dif- 
ferent species of animals vary in their habits and in the 
food they use, so we find a corresponding variation in 
the anatomy of their digestive apparatus. For instance, 
in those animals which live upon vegetable substances, 
the digestive apparatus is very complex. This is neces- 
sary because such a large amount of food is required 
in order that the proper amount of nutriment may be 
taken from it. The digestible material bears only a 
small proportion to the entire quantity of food taken. 
Therefore the alimentary canal must be very large and 
long. 
Take the case of the common fowl, whose food is 
much more concentrated than that of many other ani- 
mals. At first, the hard grains are swallowed and held 
for some time in a pouch called the crop. Here the 
food mixes with a watery secretion by which it is 
softened ; as the softened food passes down out of 
the crop it comes in contact with an acid secretion 
which is poured from glands in the walls of the tube. 
The food then passes into the gizzard, which has a 
very thick, muscular wall. This grinds and crushes 
the food, aided by the sand or gravel the animal has DIGESTION. 
59 
swallowed, until the mass is reduced to a pulpy con- 
sistence. Farther down the canal the food is mixed 
with more juices, which render it still more soluble. 
All this complicated apparatus is for the accomplish- 
ment of one object, the changing of the food so that 
it may be absorbed. 
In the ox, sheep, and some other animals, there are 
four distinct stomachs, each performing a different part 
of the digestive process. The digestive apparatus of 
man is not thus complex, because his food is compar- 
atively soft, easily made softer by cooking, and also 
because but little bulk is required to furnish the proper 
amount of nutritive material. Yet a careful study of 
the process as it exists in man, will show that it is 
filled with difficult problems. 
The Alimentary Canal. Beginning at the mouth, the 
alimentary canal extends through the body. It is about 
thirty feet in length in the adult, and is lined, its en- 
tire length, by a soft, velvety tissue called the mucous 
membrane. In this membrane are minute glands, some 
of which secrete mucus, while others secrete some of 
the digestive juices. It is in this canal that the process 
of digestion occurs. From above downwards are seen 
the following parts: the mouth, pharynx, oesophagus, 
stomach, small intestine, and large intestine. A study 
of Fig. 8 will aid in understanding the location and 
form of these several parts. 
The pharynx extends from behind the mouth about 
four and one half inches down the neck, where it be- 
comes continuous with the oesophagus. The oesophagus, 
1, is about nine inches in length, and extends from the 
pharynx to the stomach. The stomach, 2, is the most 60 
T1IE ESSENTIALS OF HEALTH. 
dilated portion of the canal. It lies transversely in the 
abdominal cavity, and is connected below with the small 
intestine, 7, which is 
about twenty feet in 
length. This termi- 
nates in the large 
intestine, 8. It will 
be noticed that the 
small intestine oc- 
cupies the center of 
the abdominal cavi- 
ty, while the large 
intestine passes 
around the borders 
of the cavity. All of 
Fig. 8, except 1, rep- 
resents that part of 
the alimentary canal 
situated below the 
diaphragm, in the 
abdominal cavity. 
Mastication. Mas- 
tication, or chew- 
ing, consists in cut- 
ting and grinding 
the food by the teeth. 
It is purely a me- 
chanical process, yet 
it is necessary in order that the food may be better pre- 
pared for the action of the digestive juices; for the finer 
the particles of food are, so much the better can these 
juices act upon them. 
Fig. 8. The alimentary canal: (1) The 
oesophagus ; (2) the stomach ; (3) the py- 
lorus ; (4) the gallbladder; (5) the duct 
carrying bile to the intestine ; (6) the duct 
from the pancreas ; (7) the small intestine ; 
(8) the large intestine. DIGESTION. 
61 
One very important result accompanying mastication 
is the thorough mixing of the food with the saliva. As 
a result of this, the food is moistened and prepared for 
swallowing, while at the same time some of its starchy 
elements are changed into sugar. The solid and semi- 
solid foods should be chewed very fine. One of the most 
common causes of stomach trouble is incomplete masti- 
cation, a result of too rapid eating. Let nothing pass 
down the throat that is not crushed and finely divided. 
The Teeth, lor reasons just mentioned, the teeth are 
most important aids to perfect digestion. As the habits 
and foods of animals differ, so do their teeth vary in 
form and function, in order to 
best serve particular needs. 
Fish and serpents, that swal- 
low their food entire, have no 
need for any cutting or grind- 
ing. The function of the teeth 
in these animals is restricted to seizing and holding the 
food. Therefore their teeth are sharp and curved, with 
the points set back- 
ward, so that when 
once the prey is caught 
it is very difficult for 
it to escape. In the 
horse and allied ani- 
mals, there are two 
kinds of teeth, — those 
in front, the incisors, for cutting off the herbage; and 
those farther back, the molars, for grinding. 
In the gnawing animals, as the rats, mice, and squir- 
rels, the incisor teeth are remarkably developed. Their 
Fig. 9. The skull of a snake. 
Fig. 10. The skull of a horse. 62 
THE ESSENTIALS OF HEALTH. 
edges are sharp and chisel-shaped, and they are directly 
opposed to each other in the upper and lower jaws. They 
are peculiar also because they grow so that, as the ends 
are worn away, the tooth is pushed up from its roots, 
thus keeping its normal length. Sometimes one of 
these animals has one of its incisor teeth broken off, 
or injured so that it fails to grow. The corresponding 
tooth in the other jaw then has no tooth against which to 
cut, and hence it is not worn away. It keeps on grow- 
ing, sometimes to an extent sufficient to cause the death 
of the animal, by preventing it from getting its food. 
Two Sets of Teeth. In man the teeth combine the 
general characteristics already mentioned; but none of 
them are capable of self-repair, neither do they grow 
nor alter in shape after they are once formed. As the 
jaws of a child are not so large as those of an adult, 
they are not large enough to hold all the teeth of a full- 
grown person. To compensate for this there are two 
sets of teeth. One set develops early in life. These 
teeth are called the milk, or temporary teeth, and are 
shed during childhood. Another set soon follows, called 
the permanent teeth. 
The first teeth of the temporary set appear about the 
sixth or seventh month; they appear one by one, until 
the whole set of ten for each jaw is complete by the end 
of the second year. In five or six years these loosen 
and are removed, and the permanent teeth begin to ap- 
pear. At twelve or thirteen years of age the full set of 
permanent teeth is present, except the wisdom teeth. 
These usually do not appear until the person is twenty 
or twenty-five years of age. The permanent teeth are 
thirty-two in number, sixteen for each jaw. They are DIGESTION. 
63 
developed in the jawbones, beneath the temporary teeth. 
When they first appear they are of their full size; there- 
fore the permanent teeth of a child twelve years of age 
are as large as they ever will be. 
Varieties in Shape and Uses. Because the teeth have 
different kinds of work to perform they are of various 
shapes. Beginning at the middle line of either jaw, and 
proceeding backwards, the teeth are placed in the fol 
Fig. 11. The teeth of an adult: (1) an incisor, or cutting tooth; 
(2) a canine, or eyetooth ; (3) molars of the lower jaw ; (4) molars of the 
upper jaw. 
lowing order : two incisors, for cutting the food; one 
canine, or eye tooth, pointed and serving the same pur- 
pose as the incisors ; two bicuspids, or small molars ; 
and three large molars, for grinding and crushing. The 
incisor and canine teeth resemble each other very much, 
only if seen in profile it would be found that the crown 
of the incisor is thinner and flatter, and has a more 
cutting edge. The crown of the canine is more nearly 
round, more pointed, and better made for tearing. The 
molars of the lower jaw differ from those of the upper, 
principally in that they have but two roots, or fangs, 
while the upper molars have three. 
The Structure of Teeth. Each tooth consists of the 
crown, or the part projecting into the mouth ; the neck, 64 
THE ESSENTIALS OF HEALTH. 
or the part surrounded by the gums; and the root, or 
the part deeply seated in a bony socket. When broken 
Fig. 12. A side view of the lower jaw with the outer walls of 
bone removed, showing the teetli in proper place : (1) the two incisors; 
(2) the canine; (3) the two bicuspids; (4) the three lower molars; 
(the last molar is sometimes called the wisdom tooth); (5) a blood vessel; 
(6) a nerve. 
open, a tooth is seen to be hollow. Fig. 13 illustrates 
the shape of this central cavity. It conforms to the 
general outline of the tooth, and thus varies in form for 
the several teeth. In the living tooth this cavity is 
filled with nerves and blood vessels, which are held 
together by a delicate connective tissue. This is called 
the pulp of the tooth. When inflamed it gives rise to 
a most intense toothache. 
Surrounding the crown of the tooth is the hardest 
substance in the body, called the enamel; around the 
root is a thin layer of bone, called cement; but the 
greater part of the tooth consists of a hard substance, 
called dentine, or ivory. The dentine surrounds the DIGESTION. 
65 
pulp cavity and extends outwards to the enamel and 
cement: in structure it is like the tusk of the elephant, 
harder than bone but not so hard as the enamel. 
The figure shows that it is 
pierced with innumerable fine 
canals that extend from the 
pulp to the very outside edge 
of the dentine. These canals 
are filled with fibers of living 
matter which are connected 
with the cells of the pulp. 
With the exception of the 
enamel, therefore, a tooth is 
a living tissue, having nerves 
and blood vessels in its cen- 
ter, bone cells in the cement 
around its roots, and innu- 
merable fibers of tissue pen- 
etrating the dentine. With 
this knowledge it is not strange 
that decay should make the 
teeth ache, and that extract- 
ing them should cause pain. 
Yet with all this living matter 
entering into their structure 
they cannot repair themselves 
when injured. They should 
receive, therefore, daily atten- 
tion and the best of care. 
Care of the Teeth. The im- 
portance of the teeth to the personal appearance, as well 
as their relation to the digestive function, is so evident 
Fig. 13. Longitudinal sec- 
tion of a tooth : (1) the enamel; 
(2) the dentine ; (3) the cement; 
(4) the pulp cavity. 66 
THE ESSENTIALS OF HEALTH. 
that it is a matter of surprise that so little attention 
is given to their care and preservation. The teeth 
should be cleaned at least once each day, while it would 
be much better to cleanse them both morning and even- 
ing. Use a small, soft brush and only the best pow- 
ders, or washes, indorsed by some responsible and well 
known dentist. Consult a dentist as soon as any cavity 
is discovered, although a better plan is to have the teeth 
examined by a dentist every few months. 
The Saliva. The saliva is a fluid mainly derived from 
three pairs of large glands. Mixed with the saliva is 
some mucus from the mucous glands situated in the 
lining membrane of the mouth. Two pairs of the sali- 
vary glands are situated beneath the tongue and between 
the two sides of the lower jawbone. The ducts which 
convey the secretions of these glands open into the 
mouth just beneath the tongue. The other pair of 
glands is situated in front of the ears. Each gland 
lies a little below and directly in front of the external 
ear. These are called the parotid glands. When they 
are inflamed they become swollen and painful, and cause 
the disease known as mumps. The duct from each 
gland opens into the mouth on the inner surface of the 
cheek opposite the second molar tooth of the upper jaw. 
A drop of the saliva examined under the microscope 
shows a number of cells that have fallen from the lining 
membrane of the mouth. As the cells become old they 
either drop off or are easily removed by the movements 
of the tongue against them. Fig. 14 illustrates these 
cells together with others which have escaped from 
the lymphatic vessels; they are therefore called lymph 
corpuscles. The vast number of epithelial cells always DIGESTION. 
67 
found in the saliva gives another striking proof that 
the body is rapidly and continuously changing; for new 
cells must take the 
place of the old, as 
rapidly as they are 
removed. 
Uses of Saliva. The 
saliva is a constant 
secretion, although 
it can be greatly in- 
creased by the move- 
ments of the jaws, 
especially when food 
is being masticated. 
The saliva is essen- 
tial in order to keep 
the tissues about the mouth and throat moist. It is 
extremely difficult to speak if the mouth be dry, as 
many a young orator knows. The nervousness caused 
by his first appearance in public temporarily checks the 
secretion of saliva, and the mouth becomes so dry that 
speaking is almost impossible. 
Fig. 14. Cells found in the saliva, mag- 
nified: (1) epithelial cells from the mucous 
membrane lining the mouth ; (2) lymph 
corpuscles that have escaped from the lym- 
phatics of the mouth. 
The principal function of the saliva is to moisten the 
food, and thus aid in its mastication and solution. It 
aids greatly, in this way, in swallowing the food, for it 
is very difficult to swallow anything that is hard and 
dry, unless first moistened with some fluid. The saliva 
is also of use, because it dissolves certain substances, 
and thus enables us to taste them; for solid bodies can- 
not be tasted. It has also a chemical action on some of 
the foods; for it is capable of changing starch into 
sugar. But owing to the short time the food is kept in 68 
THE ESSENTIALS OF HEALTH. 
the mouth, only a small amount of the starchy foods is 
thus changed. We shall learn, later, that this impor- 
tant change principally occurs below the stomach. 
As one object of the saliva is to furnish moisture, so 
that the food may be more readily swallowed, it follows 
that it is not necessary to wash down the food with large 
quantities of some fluid. As a rule, the saliva furnishes 
moisture enough, as from one to three pints are secreted 
each day. While there is no harm in using a moderate 
amount of drink with our meals, yet large quantities 
are certainly injurious, especially if they be either very 
hot or very cold. 
The Pharynx. The pharynx extends from the back of 
the nasal passages downward about four inches, where 
it becomes continuous with the oesophagus, or gullet. 
In the upper part of the pharynx, on a line with the 
floor of the nasal passages, arc the openings of two 
tubes, called the Eustachian tubes. Each tube extends 
from the side of the upper part of the pharynx to the 
nflddle ear. A disease of these tubes is a frequent 
cause of deafness. 
The pharynx is partly divided from the mouth by a 
curtain hanging down from above, called the soft palate. 
It is thus named to distinguish it from the hard palate, 
which forms the roof of the mouth. From the center 
of the soft palate there is a prolongation downward, 
called the uvula, often incorrectly called the palate. 
On eacli side of the throat, below the soft palate, is a 
tonsil. The tonsils are often enlarged, interfering with 
speech, and with the swallowing of food. When a severe 
inflammation of the tonsils occurs, it is known as the 
quinsy. DIGESTION. 
69 
Swallowing. Around the lower part of the pharynx 
are muscles which, by contracting, aid in swallowing. 
The food is prevented from entering the larynx, or 
windpipe, which is directly in front of the pharynx, by 
a valve which shuts tightly down as the food passes 
over it. Occasionally a small amount of food or drink 
gets into the air passages, causing violent coughing until 
it is expelled. The oesophagus is naturally closed, and 
thus, when a mouthful of food enters it from the phar- 
ynx, its muscular walls contract and push the food 
along until it reaches the stomach. 
QUESTIONS. 
1. What is the object of digestion ? 
2. What can you say of the digestive fluids ? 
3. Describe the digestive apparatus of the common fowl. 
4. What animals have four distinct stomachs? 
5. Give a general description of the alimentary canal. 
6. What is mastication ? Why is it necessary ? 
7. What accompanies mastication? 
8. How many sets of teeth in man ? 
9. IIow many teeth in the temporary set ? In the permanent set? 
10. Describe the different shapes .and uses of teeth ? 
11. What is found in the central cavity of a tooth*? 
12. Where is the hardest substance in the body? 
13. Describe the dentine ? 
14. IIow should we care for the teeth? 
15. Where are the three pairs of salivary glands found ? 
l(i. What does the microscope show in saliva? 
17. Give some of the uses of the saliva. 
18. IIow does the saliva affect starch? 
19. Describe the pharynx. 
20. Where is the soft palate? The tonsils? 70 
TI1E ESSENTIALS OF HEALTH. 
CHAPTER VIII. 
DIGESTION IN THE STOMACH AND 
INTESTINE. 
The Stomach. The stomach occupies the upper part 
of the abdominal cavity. To its extreme left is the 
spleen; in front is the abdominal wall; behind are the 
ribs; below are the pancreas and intestines ; above is 
the diaphragm; and to the extreme right is the liver. 
When moderately distended it is capable of holding 
about three pints. 
Fig. 15. View of the inside of the stomach. The front walls have been 
cut away, showing the mucous lining arranged in folds or plaits. 
The opening in the right end, through which the food 
passes out of the stomach into the intestine, is called DIGESTION. 
71 
the pyloric opening. It is provided with a thick mus- 
cular band arranged in a circular manner. This band 
is known as the pylorus, so named from a Greek word, 
signifying a gate. It is illustrated at 3, Fig. 8. The 
object of this band is not to allow the food to pass out 
of the stomach until it has been properly acted upon by 
the gastric juice. 
In the mucous membrane of the stomach are found 
vast numbers of minute glands. These are of the na- 
ture of tubes, or canals, lined with cells. The cells 
secrete a juice called the gastric juice. This is poured 
into the stomach, through the openings of the glands, 
whenever food is taken. 
Fig. 16 illustrates a 
section of a small por- 
tion of the walls of the 
stomach. If this section 
were viewed from above, 
the minute depressions 
would appear as circular 
openings. This section 
shows that the depres- 
sions are the openings of 
the glands. Fig. 17 illus- 
trates one of the glands, very highly magnified. A care- 
ful examination of this figure shows two kinds of cells 
in the lower part of the gland. Of such use is the 
microscope to the study of physiology that we are now 
able to understand the function of these cells, and to 
affirm that one kind of cells secretes a certain part 
of the gastric juice, while another kind secretes other 
parts. 
Fig. 16. A cross-section of a small 
portion of the walls of the stomach, 
slightly magnified, showing the glands. 72 
THE ESSENTIALS OF HEALTH. 
The Gastric Juice. The gastric juice is clear and color- 
less, in this respect resembling water. But it contains 
two marked ingredients not found in 
water; these are pepsin and an acid. 
When the stomach is empty and its 
mucous membrane thrown into folds, 
the membrane is of a pale red color, 
and there is no secretion of the gastric 
juice. Upon the introduction of food 
the mucous membrane rapidly fills 
with hlood, becomes bright red in 
color, and secretes the gastric juice in 
abundance. Not all foods are digested 
in the stomach by the gastric juice, 
for some foods pass out of it un- 
changed ; this is true of the oily and 
starchy foods. 
The chief characteristic of the gas- 
tric juice is its power to dissolve and 
digest foods of an albuminous nature, 
as the lean meats, and the white of eggs. If only the 
proper amount of these be taken, they are completely 
digested in the stomach; but if more be taken than can 
be digested by the gastric juice, it passes out into the 
intestine, where the work is completed by the pancreatic 
juice. We shall learn that the pancreatic juice possesses 
the same power to digest albuminous foods as the gastric 
juice. 
Fig. 17. One of 
tlie glands of the 
stomach, highly mag- 
nified. 
Action of Gastric Juice on Different Foods. As has been 
stated, the albuminous foods, as the lean meats, white 
of egg, etc., are digested in the stomach. In bread, 
there is gluten and starch; the former is liquefied and DIGESTION. 
73 
digested in the stomach, while the latter is unaffected. 
Fatty foods, as the fat of flesh, are affected but slightly 
by the gastric juice, and only in this way, — the gastric 
juice liquefies the tissue that surrounds the fat globules, 
thus allowing the fat to escape in the form of oil drops. 
But upon the fat itself the gastric juice lias no effect; the 
fat passes out of the stomach unchanged. Milk is coag- 
ulated, or curdled, soon after it reaches the stomach. 
This is due to the coagulation of the casein. The gas- 
tric juice digests the casein, but does not affoct the oil 
drops, or fat. The vegetable foods are digested in a 
similar manner to that already described. The albu- 
minous matters are dissolved and digested, while the 
oily and starchy ingredients are set free to pass out of 
the stomach unchanged. As the contents of the stomach 
begin to pass through the pyloric orifice they consist of 
digested albuminous foods, starch, fat, and much indi- 
gestible material. To this mixture the name chyme has 
been given. 
Movements of the Stomach. As soon as the food reaches 
the stomach and the secretion of the gastric juice com- 
mences, the muscular walls of the stomach begin to con- 
tract. These contractions produce such a movement of 
the contents of the stomach that the food and gastric 
juice are thoroughly mixed. The food is thus carried 
back and forth, to every part of the stomach, so thqt the 
whole mass may be penetrated thoroughly by the gastric 
juice, and digestion go on simultaneously in all parts. 
Conditions Affecting Digestion. The solid foods are 
more easily digested if the pieces be minutely divided; 
therefore swallowing large pieces of food retards diges- 
tion. Food should be eaten slowly, that the gastric 74 
T1IE ESSENTIALS OF HEALTH. 
juice may be formed in sufficient quantity to be thor- 
oughly mixed with it as it is swallowed. A glass of 
very cold water, hastily swallowed during a meal, might 
be sufficient to drive the blood from the mucous mem- 
brane of the stomach arid check the action of the glands. 
It might require some time for them to recover from the 
shock of the cold, during which but little, if any, gastric 
juice would be secreted. This delay would prolong di- 
gestion and be quite likely to produce some form of 
stomach trouble. Too much liquid with a meal dilutes, 
and therefore weakens the gastric juice. It is much 
better to quench the thirst before going to the table. 
Mental and physical fatigue will interfere with diges- 
tion ; therefore one should never eat a hearty meal when 
very tired, either from manual labor or from severe 
mental exercise. A short rest of a few moments before 
going to the table is a wise precaution in such cases. If 
the food be eaten slowly there is but little danger of 
overloading the stomach, but rapid eating is quite likely 
to result in overeating, which leads to many troubles. 
Constant eating, or eating frequently between meals, 
does not give the glands of the stomach time to rest, 
and an imperfect gastric juice is secreted, indigestion 
follows, and thus chronic dyspepsia is induced. 
There are many varieties of dyspepsia or disordered 
digestion. Some are easily cured by a proper course of 
diet, but many are not dependent upon the stomach 
alone, and are relieved with great difficulty. A few sim- 
ple rules, well observed, are all that are necessary for 
those who are yet young and vigorous. A knowledge of 
the principles of digestion as here given will enable each 
one to be his own guide in this particular. It is well to DIGESTION. 
75 
keep in mind the fact that the most serious effects pro- 
duced on digestion are those caused by the use of alco- 
holic drinks. 
The Time Required for Digestion. The time required 
for foods to be digested in the stomach was first ascer- 
tained by a Dr. Beaumont, who experimented upon one 
of his patients. This patient, Alexis St. Martin, had re- 
ceived a gun-shot wound directly over the stomach. 
After the wound had healed, there was found an open- 
ing which led from the surface of the body directly into 
the stomach. The opening was usually closed on the 
inside by a fold of the mucous membrane of the stomach 
falling over it; but this could be easily pushed aside and 
the whole process of digestion carefully studied. Since 
the days of St. Martin, other cases have occurred of such 
a nature that similar experiments could be made. These 
have proved that the time required for the stomach to 
complete its work depends upon many circumstances, 
some of which have already been mentioned. But in a 
healthy person it is claimed that digestion is completed 
in from one to five hours. The following table will give 
Easy of Digestion. 
h m 
Rice, boiled 1 00 
Apples, sweet, raw ... 1 30 
Milk 2 00 
Cabbage, raw 2 00 
Oysters, raw 2 30 
Potatoes, baked 2 30 
Chicken, boiled 2 45 
Eggs, soft boiled .... 3 00 
Custard, baked . . . . 3 00 
Beef, broiled . 3 00 
Moke Difficult. 
h m 
Potatoes, boiled 3 30 
Oysters, fried . . * . . 3 30 
Eggs, hard boiled .... 3 30 
Pork, broiled 3 30 
Beef, fried 4 00 
Cheese 4 00 
| Cabbage, boiled .... 4 30 
Duck, wild, roasted . . . 4 30 
Pork, fried 4 30 
Pork, roasted 5 15 
a fairly correct idea of the average time required for the 
digestion of several different foods, including those di- 76 
THE ESSENTIALS OF HEALTH. 
gested in the stomach and those which undergo this 
process farther down the alimentary canal. The time 
is given in hours, h, and in minutes, m. 
The Liver. The liver is the largest gland in the body. 
It is situated in the upper part of the abdominal cavity, 
just beneat'h the diaphragm. The greater portion of it is 
on the right side of the body, although some of it ex- 
tends over to the left side. A reference to Fig. 43 
will give an idea of its location, as well as its relation 
to the diaphragm and to the stomach. The microscope 
shows that the liver consists largely of cells. These 
cells secrete a fluid, called bile or gall During the 
intervals of digestion the bile collects in a sac, situated 
on the under side of the liver, and called the gall blad- 
der. The liver is constantly secreting this bile. The 
bile may pass directly from the liver into the intestine 
through a duct, shown in Fig. 18, at 7, or it may first 
collect in the gall bladder and pass into the intestine 
through another duct, at 8. These two ducts, however, 
unite into one, at 9, forming one large bile duct. Just 
before this duct opens into the intestine it unites with 
the duct from the pancreas, and the two terminate in a 
common opening, as shown at 10. 
The Bile. From two to three pints of bile are secreted 
each day. Many experiments have proved that if this 
secretion be prevented from entering the intestine, or if 
the liver should fail to secrete it, sickness and death will 
follow. When the ducts leading from the liver to the 
intestine become stopped up in any way, so that the bile 
is held back, the blood vessels absorb the bile and carry 
it to all parts of the body. This makes the skin yellow, 
as in cases of jaundice. The bile aids in the digestion DIGESTION. 
77 
and absorption of the oily and fatty foods. It moistens 
the walls of the intestine and renders their contents 
more liquid. It also does much to prevent the decom- 
position of food while it is in the intestinal canal. 
The Liver Sugar. We know that all the starchy foods 
must be changed into sugar before they can be absorbed; 
therefore all the starch and sugar taken into the body 
are finally absorbed as so much glucose, or grape sugar. 
This sugar is carried directly to the liver, where it un- 
dergoes a slight change. The liver stores it in its cells, 
only to give it up again to the blood as the needs of the 
body demand. 
The Pancreas. The pancreas is situated just below and 
under the stomach, and is about six inches in length. 
The duct from this gland opens into the intestine, in 
common with the bile duct, about four inches below 
the pylorus. In the lower animals the pancreas is 
known as the sweetbread. 
The pancreatic juice has a direct action on all fatty 
and oily foods. It is the only digestive juice that is able 
to completely digest the fats and prepare them for ab- 
sorption. It changes them into a white, opaque emul- 
sion, called chyle. When examined with the microscope, 
chyle is found to consist of extremely minute particles 
of fat or oil. The pancreatic juice is also capable of 
changing the starches into sugar, completing the work 
which was slightly begun by the saliva. It can also 
digest albuminous foods, although this is principally 
done in the stomach. 
The Intestinal Juice. Situated in the mucous mem- 
brane of the small intestine, are minute glands : these 
secrete a digestive fluid, called the intestinal juice. It 78 
THE ESSENTIALS OF HEALTH. 
aids in the digestion of the foods, principally the starches 
and the fats. 
Fig. 18. A diagram illustrating the position of the pancreas and its 
relation to surrounding parts ; (1) the stomach ; (2) the pylorus ; (8) the 
small intestine ; (4) the spleen ; (5) the pancreas ; (6) the duct of the 
pancreas ; (7) the bile duct from the liver; (8) the bile duct from the gall 
bladder ; (9) the common bile duct, formed by a union of the two bile 
ducts. The common bile duct unites with the pancreatic duct, and the 
one duct thus formed opens into the small intestine at 10. DIGESTION. 
79 
EFFECTS OF ALCOHOL ON THE STOMACH. 
When wine, whiskey, beer, or any other alcoholic 
liquor comes in contact with the mucous membrane of 
the stomach, it causes an increased flow of blood to the 
part. Irritated by the presence of the alcohol the glands 
throw out an extra quantity of gastric juice. On this 
account it is considered by some an aid to digestion, but 
physiologists who have studied the matter say that the 
presence of the food itself should be a sufficient stimulus, 
and that the overwork thus thrown upon the glands by 
the alcohol soon weakens them so that they throw out 
an imperfect juice. The mucous membrane becomes 
constantly red or inflamed, and later the glands become 
smaller and permanent indigestion results. 
Such an inflamed condition of the stomach is called 
gastric catarrh. The inflammation causes an unnatural 
heat in the stomach, together with a sickening, faint 
feeling. To quiet the burning sensation and to quench 
its accompanying thirst, more liquor is taken. This 
appears to give relief; but the relief is of a most decep- 
tive kind. The alcohol simply deadens for a short time 
the nerves in the stomach. The apparent temporary 
relief is to the drinker a sufficient excuse for his con- 
tinuing its use. Again and again is this experiment re- 
peated, while the inflamed stomach remains a witness 
to the folly of trying to put out a fire by continually 
adding more fuel. Persons thus addicted to the use of 
alcoholic drinks many times make earnest efforts to do 
without them ; but the craving of the inflamed stomach, 
the unnatural thirst, and the strong appetite, all appeal 
for more drink. 80 
THE ESSENTIALS OF HEALTH. 
Now, what is the condition of a man under such cir- 
cumstances ? He is ill, suffering from an inflammation 
of the stomach and a disordered liver. Weakened in 
body and in mind by the disease, he should be treated as 
a sick man, and by a skilful physician who would not 
make matters still worse by prescribing alcohol. 
The long-continued use of alcoholic drinks in large 
doses makes most marked changes in the structures of 
the stomach. The blood vessels become permanently 
distended with blood, thus interfering with proper cir- 
culation. As a result, some parts of the mucous mem- 
brane become so diseased that they break down, forming 
ulcers. This is one of the last and most severe effects. 
The ulcers give rise to the most severe pain, and this 
often leads to the use of some form of opium. 
In conclusion, we sum up the effects of alcoholic 
beverages on the stomach as follows : — 
A small dose, when not repeated. Increased flow 
of blood to the stomach; digestion retarded by the 
action of the alcohol on the gastric juice; probable 
recovery. 
A large dose, not repeated. Increase of the above 
effects; acute inflammation of the stomach; digestion 
temporarily checked. Recovery after a few days, or the 
inflamed condition may remain a long time. 
A very large dose, not repeated. Increase of the 
above effects; occasionally sudden death. Recovery 
always slow, and often incomplete. 
Small doses, when often repeated. A slow, chronic 
inflammation of the stomach, causing dyspepsia. Re- 
covery impossible while alcohol is used; but possible if 
its use be stopped. DIGESTION. 
81 
Large doses, long continued. Increase of the above 
effects; the glands become reduced in size ; the blood 
vessels are permanently enlarged; sometimes ulcera- 
tions occur. Complete recovery doubtful, even if the 
use of alcohol be stopped. 
Very large doses, often repeated. Increase of above 
effects ; stomach retains but little if any food; great 
pain ; opium used ; ulcerations deeper; hemorrhages; 
death. 
Effect on the Liver. The secretion of bile and the 
storing up of the liver sugar can only be carried on 
properly in a healthy liver. Each cell must be ready to 
do its part. Alcohol makes marked changes in the 
liver, resulting in great impairment of digestion, and, 
therefore, of the whole system. 
It is probable that nearly all the alcohol taken as 
a drink is absorbed while in the stomach. From the 
stomach, the blood vessels carry it directly to the liver, 
where it does immense harm. It may cause the liver 
to become large and fatty, as it does in those who drink 
beer. In these cases the microscope shows that each 
cell has become filled with minute globules of fat. Such 
a condition is represented in Fig. 19, at B. These fat 
globules cannot make bile, neither can they store up the 
liver sugar ; therefore the liver becomes a great mass of 
fatty tissue, unable to do the work assigned it. 
After the long-continued use of alcoholic beverages, 
especially whiskey, brandy, and gin, the liver undergoes 
other changes. It becomes greatly reduced in size and 
much too hard. Such a liver is so characteristic of 
alcohol poisoning that medical authorities have given 
it the distinct name of the “ drunkard’s liver.” The 82 
THE ESSENTIALS OF HEALTH. 
microscope shows the cells of such a liver to be much re- 
duced in size, and otherwise changed in appearance. 
The liver is probably one of the first organs to be seri- 
ously affected by alcohol. If it cannot perform its func- 
Fig. 19. (A) Liver cells, highly magnified, from a healthy liver. 
(B) Liver cells, highly magnified, from a fatty liver, the oil globules 
take the place of healthy liver substance. 
tions properly the health of the whole body will, sooner 
or later, become seriously affected. Alcohol does not 
simply interfere with the functions of the liver ; but it 
strikes deeper, and actually changes the very structure 
of that important organ. 
Effects of Tobacco on Digestion. Digestion is often im- 
paired in those who use tobacco. By chewing tobacco the 
salivary glands are constantly overworked, so that when 
the saliva is most needed, at mealtime, an insufficient 
amount is furnished. This necessitates the use of some 
other liquid to moisten the food ; therefore an excessive 
amount of water, tea, or coffee is used. The more gen- 
eral effects are of a secondary nature. The nicotine is 
absorbed in sufficient amount to affect the nervous sys- DIGESTION. 
83 
tem, giving rise to a kind of indigestion called nervous 
dyspepsia. 
Opium. Opium is such a powerful narcotic that mod- 
erate doses of it are sufficient to check nearly all the 
phenomena of life, while large doses will cause death. 
Even a moderate dose taken just after a meal may com- 
pletely arrest digestion. The use of opium often follows 
the prolonged use of alcoholic beverages, for it quiets 
the pain and restlessness of the diseased body, and it 
dulls the intellect so that the sufferings of remorse are 
not so keen. 
Tea and Coffee. Both tea and coffee are likely to 
interfere with the action of the stomach, especially if 
taken strong and in large quantities 
QUESTIONS. 
1. Name the parts surrounding the stomach. 
2. Where is the pylorus, and what is its object ? 
3. Describe the glands in the mucous membrane of the stomach. 
4. Describe the gastric juice. 
5. What is the chief characteristic of this juice ? 
6. What other juice has the same power ? 
7. What is the action of the gastric juice on lean meat? white 
of egg? bread? fatty foods ? milk? 
8. What is the object of the movements of the stomach ? 
9. Give some of the conditions affecting digestion. 
10. Name some foods easy of digestion ; some more difficult. 
11. Give the location of the liver. 
12. What does the liver secrete ? 
13. I low does this secretion reach the intestine? 
14. What is said about the liver sugar? 
15. Give the effect of pancreatic juice on the various foods. 84 
THE ESSENTIALS OF HEALTH. 
CHAPTER IX. 
ABSORPTION. 
Definition of Absorption. It has been stated in a pre- 
vious chapter that the saliva and pancreatic juice 
change the insoluble starchy foods into the soluble 
glucose, or grape sugar; that the lean meats, eggs, 
and other albuminous foods are digested by the gastric 
juice; and that the fats are changed by the pancre- 
atic juice. If our foods could be absorbed in their 
natural state, this complicated work of digestion would 
be unnecessary. But we know that the foods must first 
be liquefied and changed, before they can be taken up 
by the proper vessels, and carried to the various parts of 
the body. 
Absorption, therefore, is the process by which the 
digested food passes from the alimentary canal into the 
blood vessels and lymph vessels. 
Absorption from the Stomach. The water that is taken 
as drink, and also that found in the food, is largely 
absorbed by the blood vessels of the stomach. Such 
mineral salts as are soluble in water are here absorbed ; 
as are also the various alcoholic solutions. There is a 
slight absorption of the foods, as they are digested in ABSORPTION. 
85 
the stomach. Generally speaking, however, with the ex- 
ception of the various drinks, both simple and alcoholic, 
there is little absorption by the blood vessels of the 
stomach. The digested foods are principally absorbed 
in the small intestine. 
Structure of the Small Intestine. The outer walls of the 
small intestine are composed of involuntary muscle 
which is directly continuous with that forming the walls 
of the stomach. Within this muscular wall, and at- 
tached to it, is a mucous membrane which lines the 
whole of the small intestine. This mucous membrane 
is arranged in folds, or plaits, which pass around and 
transversely to the canal. Some of the folds are nearly 
two thirds of an inch in depth at their broadest part, 
though most of them are smaller. These folds retard 
the passage of food along the intestine, and also in- 
crease the surface for absorption. Projecting from 
these folds, and covering their inner surface are very 
minute elevations, called villi. They are from -A- to 
of an inch in length and they hang down toward the 
center of the canal like so many minute fingers. They 
give to the mucous membrane its velvety appearance. 
It is estimated that there are fifteen or twenty million 
of these villi in the small intestine. 
Fig. 21 illustrates the general arrangement of the 
various parts as seen in a cross section of the small in- 
testine. The outer wall is thick and firm, composed of 
strong muscular tissue. Within this are represented 
the villi, hanging down toward the center of the canal. 
Two kinds of vessels are illustrated in the drawing, — 
the blood vessels and the lymph vessels; the latter 
are also known as the lymphatics, or the lacteals. 86 
TIIE ESSENTIALS OF HEALTH. 
A careful study of one of these villi is necessary for 
a clear understanding of the subject of absorption. 
At Fig. 20 is a single villus, highly magnified. Each 
of those represented in Fig. 21 would appear the same 
under an equally high magnifying power; in fact, this 
single villus may be taken as a representative of the 
Fig. 20. A villus of the small intestine, magnified: (1) central lym 
phatic ; (2) blood vessels. 
Fig. 21. Diagram of a cross section of the small intestine : (1) lacteal, 
or lymphatic vessels ; (2) blood vessels. 
twenty million found in the body. Each villus is sur- 
rounded with a layer of minute cells. Directly in the 
center, 1, is a darkly shaded vessel; this is the lacteal, 
or lymphatic vessel. It begins at the free end of the 
villus and unites with the lacteals from the other villi, 
as clearly seen in Fig. 21. Surrounding the central 
lymphatic are numerous capillary blood vessels. A 
reference to Fig. 21 shows that the capillaries from 
several villi unite to make the larger blood vessels, at 2. 
The villi, therefore, are found to consist of two kinds PLATE II ABSORPTION. 
87 
of vessels, surrounded with a layer of cells. Plate II. 
gives an idea of the vast network of blood vessels found 
in each villus. No pen can either picture or describe 
this most beautiful and most complicated arrangement 
of vessels. 
Absorption from the Small Intestine. No better illus- 
tration could be given of the value of the microscopical 
study of the tissues, as an aid to the study of physiology, 
than the case before us. It is now easy to understand 
how the digested food can pass from the intestinal canal 
to the blood vessels and lymphatics. The digested foods 
can easily pass through the thin layer of cells surround- 
ing the villi, and through the thin walls of the vessels 
within. The only question to be decided is what kind of 
food each system of vessels absorbs. 
The central lymphatics, or lacteals, of the villi are 
especially concerned in the absorption of the digested 
fatty foods. The blood vessels of the villi absorb the 
other digested foods, as the glucose and the albuminous 
foods. This is the general rule, although it is a fact 
that each system of vessels may absorb all kinds of 
digested food. Water and many watery solutions are 
freely absorbed while in the small intestine. 
The Portal Vein. The blood vessels of the villi unite 
with other blood vessels from the stomach to make a 
large vein, called the portal vein. This vein goes di- 
rectly from the stomach and intestine to the liver. It 
carries the digested foods, taken up by the blood vessels, 
at once to the liver. At the proper time this food will 
pass from the liver, through certain veins, directly to the 
heart. From this central point it is soon sent out to all 
parts of the bod}7. 88 
THE ESSENTIALS OF HEALTH. 
The Lymphatics. The lymphatics of the body consist 
of the lymphatic glands and the lymphatic vessels. The 
lymphatics found in the villi are often called the lac- 
teals, because here, when filled with .the chyle or di- 
gested fats, they look white; hence lacteal, from the 
Latin word lac, milk. 
The lymphatic vessels are found in nearly every organ 
and tissue in the body. They contain a clear, colorless 
fluid, called the lymph. The general object of the lym- 
phatics is to collect the fluid that is in the tissues of the 
body and carry it back to the blood. The blood brings 
nourishment to the tissues ; this nourishment is in the 
form of a watery fluid which passes through the walls of 
the blood vessels and penetrates between the fibers and 
cells of the tissues. From this fluid the tissues take 
such ingredients as they need for their nourishment and 
growth. The fluid, therefore, soon has its very life, its 
most nourishing ingredients, taken from it by the tissues ; 
nothing is left of it but useless material: At the same 
time that the tissues are taking up nourishment, they 
are also throwing off worn-out material; this forms part 
of the fluid that is in the tissues. As already stated, 
the lymphatics gather up this fluid, so that, eventually, 
its harmful ingredients may be cast out of the body. 
All along the course of the lymphatic vessels are mi- 
nute glands, called the lymphatic glands. The lym- 
phatic glands of the neck sometimes get inflamed and 
swollen so that they can be felt beneath the skin as 
minute kernels. 
The Lymph. After a meal containing fatty foods, the 
lymph in the thoracic duct changes from a clear, watery 
fluid to a milk-white color. This is due to the fact ABSORPTION. 
89 
that the lymphatics of the villi take up the digested fats, 
or chyle, and carry them directly to the thoracic duct. 
As the digested fats are of a milky color, so the contents 
of the thoracic duct become of a like color; this only 
lasts, however, while the chyle is being absorbed. All 
the other lymphatics are constantly filled with the color- 
less lymph. As it is the business of the lymphatics to 
collect a liquid which is in the tissues and carry it 
eventually to the heart, so it follows that the flow of 
lymph is always from the periphery toward the heart, 
being in this particular like the venous blood. 
As the lymph flows through the lymphatic glands on 
its way to the heart, it meets with some changes, chiefly 
in the addition of the lymph corpuscles. These are 
minute bodies identical with the white corpuscles of the 
blood. In fact, they become the white corpuscles as 
soon as they are brought to the blood by the lymphatic 
vessels. 
The Thoracic Duet. Directly in front of the spinal 
column lies the thoracic duct. It is from eighteen to 
twenty inches in length, in the adult, and is about the 
size of an ordinary slate pencil. This duct carries the 
greater part of all the lymph and chyle into the blood ; 
while it is the central, large vessel for all the lymphatics 
of the body. There are numerous valves throughout its 
entire length, so arranged that they completely prevent 
the lymph and chyle from falling towards its lower part. 
The duct begins in the lower part of the abdominal cavity 
by a triangular enlargement, and then passes up through 
the diaphragm. When near the heart, it makes a sharp 
curve and empties into a large vein, beneath the left 
collar bone. This vein carries the lymph directly to 90 
THE ESSENTIALS OF HEALTH. 
the right side of the heart. Thus the lymph enters the 
general circulation. 
The lymph from the upper part of the right side of 
the body reaches the circulation through another lym- 
phatic duct of small size. It empties into a correspond- 
ing vein beneath the right collar bone. 
Colored Plate. A study of Plate 111. will aid in under- 
standing the relation of certain parts to each other: 
(1) the beginning of the thoracic duct; (2) the termi- 
nation of the duct in the large vein, near the heart; 
(3) the right lymphatic duct; (4) the spinal column; 
(5) the large vein which empties into the right auricle,— 
it corresponds to 2, figures 30 and 31; (6) the aorta; 
(7) the artery which carries blood to the right side of 
the head; (8) to the left side ; (9) arteries supplying 
the organs and also the tissues of the abdominal cavity; 
they are also represented in Fig. 36. 
Review. From what has been said it now becomes 
possible to trace the foods from the time they are 
taken into the mouth until they enter the blood. Take 
the three representative foods : lean meat, starch, 
and fat: — 
First, mastication, or chewing; second, insalivation, 
or mixing with the saliva ; third, deglutition, or swallow- 
ing ; fourth, stomach digestion, for the albuminous 
foods; fifth, intestinal digestion, for the fatty and 
starchy foods; sixth, absorption , seventh, albuminous 
foods and glucose carried to the liver by blood vessels; 
eighth, fatty foods, the chyle, carried to the blood by 
the lacteals. 
A study of Fig. 22 will aid the memory in fixing the 
facts already stated. Begin with the four villi at the PLATE III ABSORPTION. 
91 
right of the intes- 
tine : suppose the 
central lacteals are 
filled with chyle, 
or digested fats. 
The four lacteals 
unite to form a lar- 
ger vessel, L, which 
passes through a 
lymphatic gland, 
G, and empties 
into the dilated be- 
ginning of the tho- 
racic duct, D. The 
chyle then passes 
up the duct in the 
direction of the 
arrowheads, until 
it enters the large 
vein which leads 
directly to the right 
side of the heart. 
Consult also the 
colored plate. 
Suppose again 
that the blood ves- 
sels of the villi at 
the left, 2, are filled 
with absorbed 
foods derived from 
the lean meats and 
starches. The ves- 
Fig. 22. Diagram illustrating the course 
of the absorbed foods, i, intestine : (1) villi 
with central lacteals ; (2) villi with blood ves- 
sels. l, lymphatic or lacteal vessels. G, lym- 
phatic gland, d, thoracic duct, p, portal 
vein. l, liver, at the left of the figure, 
v, vein, h, heart. A, right auricle of heart. THE ESSENTIALS OF HEALTH. 
92 
sels soon unite to form the portal vein, P, which carries 
the food directly to the liver, L. From the liver it can 
pass through the veins, in the direction of the arrow- 
heads, to the right side of the heart. 
Fig. 22 is a diagram to illustrate the course pursued 
by the digested foods, from the intestinal canal to the 
heart; while the colored plate is a correct representa- 
tion of the relation of the various parts. 
QUESTIONS. 
1. Give a definition of absorption. 
2. What food is largely absorbed while in the stomach ? 
3. Is much of the food absorbed while in the stomach ? 
4. Where does absorption principally take place? 
5. What composes the outer walls of the small intestine ? 
6. What is within this wall? 
7. How is this membrane arranged ? 
8. What is the object of these folds ? 
9. What projects from these folds ? 
10. Describe a single villus. 
11. What is said of the number of these villi? 
12. What foods are principally absorbed by the lacteals ? By the 
blood vessels ? 
13. Where is the portal vein ? 
14. Why are the lymphatics of the villi often called lacteals? 
15. What is the principal object of the lymphatics? 
16. What minute bodies are found in lymph? 
17. These corpuscles become what? 
18. Describe the thoracic duct. 
19. Of what use are its valves ? 
20. Describe the course of the digested fats from the intestine to 
the heart. Also the course of the digested lean meats. THE BLOOD. 
93 
CHAPTER X. 
THE BLOOD. 
General Description. The blood is often called the 
vital fluid, because it affords life to all the tissues. A 
sudden loss of much blood causes great weakness, while 
if the amount lost be considerable, death may result. 
The more rapid the loss of blood, the more dangerous 
it is; while if the amount be moderate and the bleeding 
slow, the loss is better borne and sooner made up. 
In a few cases human lives have been saved, after 
great losses of blood, by having fresh blood from a 
person or animal injected into the veins. This is called 
the transfusion of blood. Three or four ounces only are 
injected, and a few cases are on record where this small 
amount was sufficient to restore health to persons who 
were very near death. Many years ago a few remark- 
able cases of recovery made some people believe that the 
transfusion of the blood of young persons into the veins 
of the aged would bring back youth and vigor to the lat- 
ter. But a number of deaths resulted from this being 
improperly done, and in some countries the operation 
was forbidden by law. It is rarely employed at the 
present time. 94 
THE ESSENTIALS OF HEALTH. 
Although the blood is very generally distributed 
through the body, yet there are parts in which it is not 
found, as the hard parts of the teeth, the hair, the nails, 
the outer layer of the skin, some parts of the eye, and 
most of the cartilages. TJiese are nourished by absorb- 
ing the fluids which escape from neighboring blood ves- 
sels. It is estimated that about one twelfth of the 
weight of the body is composed of blood. 
Medium of Exchange. The blood receives a large 
amount of new material from the digested food, and a 
supply of oxygen from the air in the lungs. It carries 
these fresh supplies to the various organs and tissues; 
gives them up where they are needed ; and receives in 
exchange, carbonic acid and other products of waste. 
From this it is seen that the blood always contains both 
new and old material; new material on its way to build 
up tissue, and old material on its way to the kidneys, 
the lungs, and the skin. The blood brings useful ma- 
terial and takes away useless material. It is a great 
medium of exchange between the outside world and the 
tissues of the body. 
Composition of the Blood. Blood appears to the un- 
aided sight as a thick, opaque, red fluid. But the 
microscope shows that it consists of two parts : a trans- 
parent, nearly colorless fluid, called the plasma; and a 
large number of minute bodies floating in the plasma, 
called the blood corpuscles. The plasma looks very 
much like water, yet it holds in solution many impor- 
tant substances. 
The Blood Corpuscles. The blood corpuscles are of two 
kinds, the white and the red. The white corpuscles, as 
their name indicates, are without color. They are spher- THE BLOOD. 
95 
ical bodies, averaging about 2-5V0 °f an i*1 diame- 
ter. They are a trifle larger than the red corpuscles, 
but not so abundant, the average number being one white 
corpuscle to about three hundred red, although this is 
subject to variation even in health. The white corpus- 
cles are capable of changing their form by a flow of 
their substance in various directions. This is after the 
manner of the amoeba, as illustrated in Fig. 2 ; hence 
the changes in their shape are called the “ amoeboid 
movements.” The white corpuscles are identical with 
the lymph corpuscles. When, in cases of illness, the 
person becomes weak and pale, there is generally an 
increase in the number of the white corpuscles, and a 
decrease of the red. 
The red corpuscles of human blood are circular bodies, 
FIG. 23. 
FIG. 24. 
Fig. 23. Human blood, highly magnified : (a) the v/hite corpuscles ; 
(b) the red corpuscles. 
Fig. 24. Human blood, more highly magnified: (a) the red cor- 
puscles; (b) a white corpuscle. 
slightly hollowed towards the center. Fig. 23 shows a 
number of these bodies, shaded in the center to give 
the correct impression that they are concave. One cor- 
puscle, at the left of the figure, is seen on the edge, THE ESSENTIALS OF HEALTH. 
showing that it is biconcave, or slightly hollowed on 
either side. The red corpuscles exist in vast numbers. 
It is estimated that in a minute drop of blood there are 
over five millions of them ; while in a medium-sized 
person there are not less than twenty-five billions, 
— too vast a number for the mind to comprehend. 
Fig. 24 represents a few red corpuscles and one white 
corpuscle, very highly magnified. Four red corpuscles 
are seen resting on the side, while four are on the 
edge. 
Function of the Red Corpuscles. The most important 
ingredient of the red corpuscles is their coloring matter, 
called haemoglobin. This substance has a strong lik- 
ing, an “ affinity,” for oxygen. So strong is this affinity 
that when the blood flows through the lungs the color- 
ing matter takes oxygen from the air which it finds 
there. The red corpuscles thus become loaded with 
oxygen. The blood soon leaves the lungs, and Hows 
to the most distant tissues, which are in great need of 
this oxygen. But the tissues exert a stronger affinity 
for the oxygen than even the haemoglobin, and thus the 
latter is obliged to give up the oxygen. For this reason 
the red corpuscles are called the oxygen-carriers; for 
their great object is to carry oxygen from the lungs to 
all the various organs and tissues of the body. 
Arterial and Venous Blood. As soon as the red cor- 
puscles receive their fresh supply of oxygen in the lungs 
they become bright red in color, making the whole 
blood a bright scarlet. This bright-colored blood is 
called arterial blood. It is found in the arteries, or in 
those vessels which carry blood from the heart to the 
distant tissues. In one place arterial blood is found in THE BLOOD. 
97 
the veins,— the pulmonary veins, — which carry the 
blood from the lungs to the left side of the heart. 
When the blood is passing through the smallest ves- 
sels, the capillaries, it gives up its oxygen to the tissues. 
Deprived of its oxygen, the hasmoglobin of the red cor- 
puscles becomes much darker in color, therefore the 
whole blood looks darker. This darker-colored blood 
is called venous blood. It is found in all the blood 
vessels which carry the blood from the tissues back to 
the heart. It is also found in one artery, — the pulmo- 
nary artery, — which carries the blood from the right 
side of the heart to the lungs. The rule is that the 
arteries contain the bright arterial blood, and the veins 
the dark venous blood; but to this there are the two 
exceptions already given, the pulmonary artery and the 
pulmonary veins. 
Oxygen and Carbonic Acid. The air we breathe con- 
sists principally of two gases, — oxygen and nitrogen. 
The oxygen is essential to all life. Without it we should 
soon die. All parts of the body use it. The tissues are 
constantly demanding it and countless numbers of cor- 
puscles are continuously and rapidly at work distribut- 
ing it throughout the body. We know that a substance 
called carbon forms a part of all the tissues. When the 
oxygen reaches the tissues, it unites with their carbon, 
forming carbonic acid. This is a poisonous gas, and the 
body must cast it off as soon as possible; therefore it 
mingles with the plasma of the blood and is soon carried 
to the lungs, where it escapes from the body. 
Arterial and Venous Blood Compared. From what has 
been said we are able to place in a more concise form 
the differences between arterial and venous blood : — 98 
THE ESSENTIALS OF HEALTH. 
Arterial blood contains the more oxygen. 
Venous blood contains the more carbonic acid. 
Arterial blood is of a bright scarlet color. 
Venous blood is of a darker, nearly purple color. 
Arterial blood parts with its oxygen in the capillaries. 
Venous blood parts with its carbonic acid in the 
lungs. 
Arterial blood contains substances for the nutrition of 
the tissues. 
Venous blood contains the worn-out materials from 
the tissues. 
Coagulation. Soon after blood has escaped from a 
blood vessel, it thickens to a jelly-like mass. This is 
called the coagulation or clotting of blood. It is one of 
the wise provisions of nature, so that our lives may not 
be sacrificed as a result of some slight cut or wound. 
The lower animals are often severely bruised and 
wounded, and they may even lose a portion of a limb, 
laying bare large blood vessels, without fatal results. 
This is because the blood soon clots, forming a solid 
mass at the openings of the vessels and preventing any 
further escape of blood. Whenever any vessel of consid- 
erable size is ruptured, it is advisable to aid nature by 
checking the flow of blood for a short time, in order that 
the clot may be well formed. This is accomplished by 
pressing on the part, or by placing a fine thread around 
the ends of the ruptured vessel. 
Blood seldom clots while in the blood vessels of the 
living body. It never does so unless some disease or 
some unusual condition be present. As a result of a 
diseased condition of the walls of the blood vessels, 
sometimes a vessel in the brain breaks, and a small THE BLOOD. 
99 
amount of blood escapes into the brain substance, where 
it clots. This often produces unconsciousness and par- 
alysis, and may terminate in death. If the amount 
of blood thus set free be large enough, or if it be in 
the most vital parts of the brain, it may cause instant 
death. This bursting of a blood vessel and consequent 
pressure on the brain causes the disease known as 
apoplexy. 
The clotting of the blood is due to the change of 
some of its liquid elements into a substance called 
fibrin. Fibrin consists of innumerable delicate fibrils, 
so minute that they are seen only with the higher 
FIG. 25. 
FIG. 26. 
Fig. 25. A bowl of recently coagulated blood ; the clot is of uniform 
density. 
Fig. 26. The same bowl of blood, a few hours later ; the clot is con- 
tracted and floats in the liquid serum. 
powers of the microscope. The fibrils are like so many 
minute threads, which entangle the blood corpuscles 
and form with them a soft, semi-fluid mass. In a few mo- 
ments after blood has been exposed to the air, it begins 
to change to a jelly-like mass. Still later the mass 100 
THE ESSENTIALS OF HEALTH. 
begins to contract, while there escapes from it a clear 
fluid, called the serum. Later on the central mass 
becomes quite hard, so that it may be cut with a 
knife. This central hard mass is known as the clot, 
and consists of the fibrin and the corpuscles; while 
the serum represents the other constituents of the 
blood. 
The Blood of the Lower Animals. In many animals 
the red corpuscles are of the same shape as in man. 
With the one single exception, the camelidae, this is true 
of all the mammalia, — as the horse, sheep, ox, hog, 
and dog. While the red corpuscles of these animals are 
of the same shape, yet many of them differ in size. In 
many of these animals the red corpuscles are so much 
smaller than those in man that it is sometimes possible 
to tell whether the corpuscles found in a blood stain are 
those of man or of some lower 
animal. To determine this re- 
quires the very highest powers 
of the microscope, very delicate 
measuring instruments, and also 
great skill in their use. It is not 
always possible to tell human 
blood from the blood of other 
mammalia, but it is possible to do 
so in certain cases. 
Many of the lower animals have 
red corpuscles of different shape 
from those of man. They are 
also larger and of different structure. The red cor- 
puscles of the blood of birds, fishes, reptiles, frogs, and 
toads are oval in shape, and much larger than those of 
Fig. 27. Frog’s blood, 
highly magnified : (a) the 
white corpuscles; (b) the 
nucleated, oval, red, cor- 
puscles. THE BLOOD. 
101 
man. It is comparatively easy to tell these corpuscles 
from the circular ones, as a glance at Figs. 23 and 27 will 
show. 
Advantage is often taken of these facts, when great 
crimes have been com- 
mitted, in order to de- 
termine whether a blood 
stain was caused by hu- 
man blood or by the 
blood of one of the lower 
animals. Thus a knowl- 
edge of histology and the 
use of the microscope 
often aids in detecting 
crime and bringing the 
guilty to punishment. 
Fig. 28 illustrates 
what has been said. 
The red corpuscles from 
thirteen different ani- 
mals are illustrated, 
showing their relative 
sizes. Six are from the 
mammalia, showing a 
difference in size but 
not in shape; they are 
therefore easily told 
from the others which 
are oval. The first six 
have no nuclei, while 
the nucleus shows 
prominently in each of the others. 
Fig. 28. Showing the relative size of 
red blood corpuscles of different animals: 
(1) musk deer; (2) horse; (3) mouse; 
(4) man ; (5) whale ; (6) elephant ; 
(7) humming bird ; (8) pheasant ; 
(9) pigeon ; (10) snake ; (11) crocodile ; 
(12) triton ; (13) proteus. 102 
THE ESSENTIALS OF HEALTH. 
ALCOHOL AND THE BLOOD. 
It is the testimony of eminent surgeons that wounds 
do not heal so well on those who use alcoholic drinks. 
The continued use of alcoholic beverages results in such 
changes in the blood that the fibrin is not so easily 
foftned ; and as the formation of fibrin is necessary for 
the coagulation of the blood, it follows that bleeding is' 
not so easily checked. Therefore surgical operations are 
not so successful when performed on those whose sys- 
tems have been weakened by the long use of alcoholic 
drinks. 
QUESTIONS. 
1. What is said about the loss of blood causing weakness and 
death ? 
2. What do you understand by the transfusion of blood ? 
3. Name some parts in which blood is not found. 
4. Explain why the blood is a medium of exchange. 
5. What is the composition of the blood ? 
6. How many kinds of blood corpuscles are there? 
7. Describe the white corpuscles. 
8. Describe the red corpuscles. 
9. Explain the function of the red corpuscles. 
10. Where is arterial blood found? Venous blood? 
11. How necessary is oxygen to the body? 
12. How is carbonic acid formed in the body? 
13. Give some of the differences between arterial and venous blood. 
14. Describe the clotting of blood. What causes it ? 
15. Of \vhat does the clot consist? The serum ? 
16. What animals have red corpuscles of the same shape as in man ? 
17. What animals have red corpuscles of different shape from 
those of man ? 
18. In what way does alcohol affect the blood ? THE CIRCULATION. 
103 
CHAPTER XI. 
THE CIRCULATION. 
The Circulatory Apparatus. We have learned that the 
blood is a great circulating medium by which nourishing 
material is carried to all parts of the body, and other 
material brought to organs and tissues to be cast out as 
of no further use. To bring this about there are four 
different parts to the circulatory apparatus, — the heart, 
the arteries, the capillaries, and the veins. 
The Heart. The heart is situated in the thoracic 
cavity, between the lungs. It is completely surrounded 
by a sac or membranous bag, called the pericardium, the 
lower part of which rests on the diaphragm. This sac 
also encloses about two inches of the large blood vessels 
at the base of the heart. The cells which cover the 
inside of the pericardium secrete a watery fluid which 
keeps its inner lining very smooth and enables the heart 
to move against it without friction. The heart itself is 
a large, hollow muscle, weighing from ten to twelve 
ounces, and measuring about five inches in length. 
The heart is placed obliquely in the chest. It is con- 
ical in shape, with the apex of the cone pointing down- 
ward, forward, and to the left. The location of the 104 
THE ESSENTIALS OF HEALTH. 
apex can be easily determined by placing the hand over 
the left side, and feeling the strokes against the walls of 
the chest. The upper end or base of the heart is on a 
level with the cartilage of the third rib. 
A reference to Fig. 
29 shows that the 
heart is not all on the 
left side of the body. 
It extends about 
three inches to the 
left of the median line, 
and an inch and a half 
to the right of it. The 
apex of the heart is 
well over in the left 
side, and as low down 
as between the fifth 
and sixth ribs. The 
apex has considerable freedom of motion, while the base 
has but little motion. 
Fig. 29. The position of the heart. 
The Cavities of the Heart. The heart is divided length- 
wise by a firm muscular wall. There is no connection 
whatever between the two parts thus formed; one side 
always containing arterial blood, and the other side ven- 
ous blood. Each side of the heart is again divided by a 
wall, which, in this case, is not complete; an opening 
is left so that blood freely passes from one part to the 
other. This opening is protected by valves which allow 
the blood to pass only in one direction. There are, 
therefore, four compartments or cavities in the heart. 
The two upper cavities are called the auricles, from 
their fancied resemblance to ears; while the two lower PLATE IV. THE CIRCULATION. 
105 
cavities are called the ventricles. Each side of the 
heart, therefore, consists of an auricle above and a ven- 
tricle below. The ventricles have no communication 
with each other, neither have the auricles; but each 
auricle has an opening into its own ventricle, protected 
by valves. All these cavities are lined by a very smooth 
membrane. The col- 
ored plate is drawn from 
the same specimen as 
Fig. 30. It represents 
the right side of the 
heart as filled with the 
dark (blue) venous 
blood, and the left side 
filled with the bright 
(red) arterial blood. 
A study of Fig. 30 will 
aid to a better under- 
standing of the above 
facts. The right side of 
the heart is represented 
at 3 and 4, while 6 and 
7 represent the left side. 
The wall between the 
two is directly beneath 
the small blood vessel 
shown on the outside 
of the heart, to the left 
of the number 7. Several blood vessels course over 
the heart, giving its muscular tissue proper nourish- 
ment. A careful study of each side of this organ will 
show that the right side is divided into two parts by 
Fig. 30. The heart and the larger 
vessels at its base or upper part: 
(1) and (2) veins; (3) right auricle; 
(4) right ventricle ; (5) pulmonary ar- 
tery ; (6) left auricle; (7) left ven- 
tricle ; (8) aorta. 106 
TIIE ESSENTIALS OF HEALTH. 
a cross partition. These parts are represented by the 
numbers 3 and 4, the former being the right auricle, and 
the latter the right ventricle. The large vessels, 1 and 
2, go to the right auricle, and one large vessel, 5, pro- 
ceeds from the base of the right ventricle. The left side 
of the heart is partly hidden from view, still the num- 
bers 6 and 7 show the corresponding left auricle and 
ventricle. Coming from the left ventricle is the largest 
artery in the body, 8, the aorta. The vessels entering 
the left auricle are hidden from view, but they are rep- 
resented in the following diagram. Fig. 30 is a fairly 
correct anatomical representation of the heart, with the 
relative size of its various parts, while Fig. 31 is de- 
cidedly a diagram. 
The Contractions of the Heart. The auricles always 
contract together. This contraction is immediately fol- 
lowed by that of the ventricles; these also contract 
together. When the auricles contract they force their 
contents into the ventricles ; when the ventricles con- 
tract the valves between the auricles and ventricles 
close, so that the blood cannot flow back again. Thus 
the blood is forced out into the arteries. After the ven- 
tricles cease to contract and again relax, the blood is 
prevented from flowing back into them by means of 
valves. Therefore, valves are found between the auri- 
cles and the ventricles, and between the ventricles and 
the arteries. Should these valves fail to close and 
thus to prevent the blood from flowing in the wrong 
direction, the most serious results might follow. Occa- 
sionally the valves become so diseased that they do not 
completely stop the flow of blood backward, producing 
a peculiar murmur in the heart sounds, which the phy THE CIRCULATION. 
107 
sician is able to detect at once. There is great danger 
from such a condition, as it often produces instant death. 
Each ventricle holds from four to six ounces of blood. 
The earlier investigators placed the amount even below 
four ounces, but a number of the most recent authorities 
place it fully as high as six ounces. 
The Course of Blood through the Heart. The circula- 
tion of the blood through the heart is as follows: from 
large veins into the right auricle; then through the 
right ventricle; from this through the lungs; then 
through the left auricle; and finally through the left 
ventricle into the large aorta at its base. Briefly : right 
auricle, right ventricle, lungs, left auricle, left ventricle. 
A careful study of the diagram, as represented in 
Fig. 31, will render this more clear. The blood is re- 
turned from the tissues to the heart by numerous veins. 
These keep uniting, until at last there are only two. 
The large vein represented at 1 returns the blood from 
the lower part of the body, while 2 is the vein which 
returns the blood from the upper part of the body. 
Both these large veins pour their venous blood into the 
right auricle, 3. When this becomes filled to its normal 
limit it contracts and forces the blood through the open- 
ing in the direction of the arrowhead, into the right 
ventricle, 4. When this is filled, it contracts. As soon 
as it does so, however, the blood is forced back against 
the half-opened doors, the valves, causing them to close 
suddenly. 
As no blood can return into the auricle, 3, it is forced 
into the small opening at 5, which is the beginning of 
the pulmonary artery. When the right ventricle again 
relaxes, the blood from the pulmonary artery cannot 108 
THE ESSENTIALS OF HEALTH. 
flow back into it, owing to the closure of the valves, 
represented hy Y immediately below the figure 5. The 
dark blood then flows through the lungs, giving off its 
carbonic acid and receiving a fresh supply of oxygen. 
It finally passes through the lungs, entering the four 
pulmonary veins, at 6, 
as bright arterial blood ; 
these veins bring the 
blood to the left auricle, 
7. When filled the au- 
ricle contracts, forcing 
its contents into the left 
ventricle, at 8. When 
the left ventricle con- 
tracts, the valves between 
it and the left auricle 
close, in the same man- 
ner and at the same time 
as those on the opposite 
side. The blood is then 
forced out into the large 
aorta, 9. From this ar- 
tery the blood cannot 
return to the heart, for 
valves guard the opening here also. On through the 
arteries the blood flows until the finest capillaries are 
reached. Here the proper nourishment is given off to 
the tissues, and some of the worn-out material received 
in its place. The blood, now dark and impure, returns 
through the veins to the right side of the heart, only to 
start again on another journey just such as we have 
described. 
Fig. 31. A diagram illustrating 
the flow of blood through the heart: 
(1) and (2) veins; (3) right auricle; 
(4) right ventricle ; (5) pulmonary ar- 
tery; (6) pulmonary veins; (7) left 
auricle ; (8) left ventricle ; (9) aorta. THE CIRCULATION. 
109 
The Left Ventricle Stronger than the Right. The left 
ventricle has to contract with force sufficient to send the 
blood to the most distant parts of the body; while the 
right ventricle has to send the blood only to the lungs, 
which are but a short 
distance from it. 
Therefore, we should 
expect to find the 
left side of the heart 
stronger ; that is, its 
muscular walls 
should be thicker. 
In this case we are 
not disappointed, for 
a cross section of 
the heart through the ventricles appears as illustrated 
in Fig. 32. This shows the relative thickness of the 
walls of the ventricles in their contracted state, and 
also the difference in the shape of the ventricles. To 
the right of the figure is the nearly circular cavity of 
the left ventricle, surrounded by thick walls. To the 
left is the flattened cavity of the right ventricle, with 
much thinner walls. 
Fig. 32. A cross section of the ventricles of 
the heart. 
The Pulsations of the Heart. The beat of the heart is 
involuntary and subject to much variation. The aver- 
age frequency of the pulse in man is about 70 per min- 
ute ; while in woman it is about ten more each minute. 
This average may be greatly increased for a short time 
by many circumstances, but if the increase be long con- 
tinued it denotes some disturbance of the system. An 
excessive rapidity of the pulse, continuously beating 150 
or 160 a minute, indicates great danger; while a very 110 
THE ESSENTIALS OF HEALTH. 
slow pulse, much below the normal, also indicates seri- 
ous trouble. Some persons naturally have a pulse much 
above or even below the average. It is said that the 
pulse of Napoleon I. was but 40 per minute. The pulse 
varies greatly with the age. At birth it is about 130. 
It gradually falls until at three years of age it is about 
100; at fourteen, about 80 ; and at twenty-one, about 
the average for the adult. 
Muscular exercise accelerates the pulse. The mus- 
cular effort of standing makes a normal difference of 
ten beats per minute more -than when lying down. 
Active exercise, as running and jumping, increases 
the pulse. Excitement, as joy and anger, increases the 
number of beats ; while sorrow and depression of spirits 
may cause the number to be reduced. Any sudden 
excitement, as fright, will cause the heart to beat vio- 
lently, so that it is felt to strike with much force against 
the walls of the chest. Excessive fear, joy, or grief, 
may have an effect on the nervous system powerful 
enough to cause the heart’s action to cease, producing 
instant death. Taking the seasons through, the heart 
beats faster in summer than in winter. 
The Heart Works and Rests. The heart does an im- 
mense amount of work. At the rate of seventy beats 
per minute, there are a hundred thousand contractions 
daily. The labor expended by the heart each day is 
equal to a force required to lift 120 tons a foot from the 
ground. 
If the heart does such an amount of work, it must 
have rest. We find there is a period of time when it is 
completely at rest. The auricles contract together; im- 
mediately after, the ventricles contract, also ; and fol THE CIRCULATION. 
Ill 
lowing their contraction there is a period of complete 
rest, after which the auricles contract again. Brief as 
this period is, it yet represents about one fourth of the 
time of a whole beat. From this it is seen that the sum 
of all these brief periods for a whole day is not less than 
six hours. 
The Sounds of the Heart. If the ear be placed over 
the heart two distinct sounds are heard, one immediately 
following the other. After a moment of silence they 
are repeated. It is noticed that these two sounds cor- 
respond with each beat of the heart. The first sound is 
comparatively long and dull; the second, almost imme- 
diately following it, is sharper, shorter, and more dis- 
tinct. The sounds are likened to those produced by 
pronouncing the words tubb, dap. The whole time of 
the pulsation of the heart may be divided into four 
parts ; the first sound, two parts; the second sound, 
one part; and the period of rest, one part. 
The first sound is caused by the sudden closure of the 
valves which are between the auricles and the ventricles ; 
together with the sound caused by the powerful contrac- 
tion of the muscular walls of the ventricles. The first 
sound is, therefore, a valve sound and a muscle sound. 
The second sound is caused by the sudden closure of 
the valves which are at the beginning of the pulmonary 
artery and the aorta. It is, therefore, entirely a valve 
sound. 
The Pulse. During life the arteries are always full of 
blood, but as their walls are elastic they can be distended 
so that at times they may contain more blood than at 
others. Each contraction of the heart suddenly forces a 
quantity of blood into these elastic tubes, distending 112 
THE ESSENTIALS OF HEALTH. 
their walls. When the heart relaxes, the over-distended 
arteries would force the blood back into it were it not 
for the closure of the valves; these fully prevent any 
backward flow. As the blood cannot go in a backward 
direction, it is pushed forward under the pressure of the 
elastic walls of the arteries. Thus the arteries relieve 
themselves of the excess of blood, so that their walls 
are not so fully distended. But no sooner have the 
arteries returned to their former size than they are again 
expanded by another contraction of the heart. This 
series of expansions of the arteries give rise to the pulse, 
which is present in all arteries. Therefore each arte- 
rial expansion, or each pulse, represents a contraction 
of the ventricles. The pulse thus becomes a guide for 
ascertaining the frequency and regularity of the heart’s 
action, and the condition of the general circulation. 
As nearly all the arteries are deep-seated, only those 
few near the surface are used to study the pulse. The 
radial artery at the wrist is usually chosen for this pur- 
pose, although the pulse may be felt on the temple, the 
neck, and other places. It is possible to see the pulsa- 
tions of an artery with the unaided eye, such pulsations 
showing at times on the temple, on the neck, or at the 
wrist. 
Arteries. The arteries are the vessels which carry the 
blood from the heart to the various parts of the body. 
The word “ artery ” is derived from two Greek words 
which signify “receptacle of air;” for the ancients be- 
lieved that these vessels contained air in the living body. 
This belief was probably founded on the fact that the ar- 
teries are usually found empty in the dead body. This 
condition exists because after the heart ceases to beat, the THE CIRCULATION. 
113 
elastic walls of the arteries contract with sufficient force 
to push all their contents forward into the capillaries 
and veins. 
The arteries are cylindrical, firm, and elastic canals. 
Their lining membrane is a continuation of the mem- 
brane lining the heart. Their walls are composed 
largely of elastic and muscular tissue. The strong elas- 
tic tissue allows the artery to expand without danger of 
bursting. The muscular tissue gives contractile power 
to the artery, so that it can accommodate itself to the 
amount of blood it contains. The muscle is of the in- 
voluntary variety, and the cells are arranged around the 
tube, so that their contraction will diminish the size of 
the canal. In the smaller arteries this power is of great 
use. The muscle 
coat is very promi- 
nent there, and its 
degree of contrac- 
tion determines the 
size of the vessel. 
As the contraction 
of the muscle is un- 
der the control of 
the nervous system, 
so there are many 
circumstances 
which will affect the 
size of the artery. 
The muscular and 
elastic coats cause the artery to retain the circular 
shape when it is cut across, so that it resembles a tube. 
After repeated divisions of the arteries they become 
Fig. 33. a, a small artery ; c, capillaries ; 
Y, a small vein. 114 
THE ESSENTIALS OF HEALTH. 
very small, so that they can only be seen with the high- 
est powers of the microscope. Even the muscular and 
elastic coats disappear, and only the thin lining mem- 
brane is left. 
The Capillaries. When the artery has become so small 
that it has only the thin membrane for its wall, it is 
called a capillary. The capillaries are the most minute 
blood vessels which penetrate the organs and tissues of 
the body. They bring the blood in very close contact 
with the cells of the tissues; for between the living tis- 
sues and the blood in a capillary, there is but the thin- 
nest membrane. Many of the capillaries are so small 
that when the blood flows through them the corpuscles 
have to pass in single file, as there is not room enough 
for them to flow side by side. 
The Veins. Soon the capillaries unite with each other 
to make larger vessels, and their walls become thicker. 
The vessels are now called veins. The veins convey the 
blood from the capillaries toward the heart. The smaller 
veins unite to make larger ones, until at last the large 
veins are formed which empty into the right auricle of 
the heart. The walls of the veins are much thinner and 
less elastic than the walls of the arteries. If a vein be 
cut across, it will collapse and appear flat, because there 
is but little muscular and elastic tissue in its walls. 
Nearly all the veins have valves to prevent the back- 
ward flow of the blood. This is illustrated in the ac- 
companying figures. It is evident that if the blood flows 
in the direction of the arrow-head, in Fig. 34, the valves 
will remain open, but if it should attempt to flow in the 
opposite direction, as in Fig. 35, the valves would close 
and completely shut off the passage. THE CIRCULATION. 
115 
Rapidity of the Circulation. The blood nearest the 
heart, in the aorta, flows the most rapidly; for all the 
force of the heart’s contraction makes itself felt here. 
As the arteries divide, the stream becomes less rapid until 
FIG. 34. 
FIG. 35. 
Fig. 34. The valves of a vein, open. 
Fig. 35. The valves of a vein, closed. 
in the capillaries it is much slower. It is estimated that 
the blood in the aorta flows five hundred times faster 
than it does in the capillaries. In the veins the flow is 
faster than in the capillaries, but it does not equal the 
speed acquired in the arteries. In the large arteries 
the blood flows at the rate of about a foot per second. 
A quantity of blood can leave the heart, make a com- 
plete circuit of the circulation, and reach its starting- 
place again in less than half a minute. 
The General Circulation. A study of Fig. 36 will give 
an idea of the manner of distribution of the principal 
blood vessels. In this figure, N represents the neck ; D, 116 
THE ESSENTIALS OF HEALTH. 
the diaphragm ; and A, 
the lower border of the 
abdominal cavity. Let 
us follow the course of 
the largest artery in the 
body, the aorta, which 
is nearly an inch in di- 
ameter. It is repre- 
sented in Fig. 30 at 8, 
and in Fig. 31 at 9. In 
Fig. 36, its beginning 
is shown by the dotted 
lines, giving its origin 
from the left ventricle. 
It passes upward a 
short distance, then 
arches backward to the 
left, and so descends by 
the side of the vertebral 
column. It passes down 
through an opening in 
the diaphragm, D, and 
continues down the ab- 
dominal cavity, until at 
its lower part it divides 
into two branches, 
which supply the lower 
extremities with blood. 
Fig. 36. A diagram, showing the 
general plan of the circulation : N, the 
neck; d, the diaphragm ; a, the lower 
border of the abdominal cavity; v, veins returning the blood to the right 
side of the heart. All other vessels represent arteries, which carry blood to 
the following parts : (1) to the head ; (2) to the arms ; (3) to the legs ; (4) to 
the liver ; (5) to the stomach, pancreas, and spleen ; and (6) to the kidneys. THE CIRCULATION. 
117 
From the arch of the aorta, branches arise which 
supply the head with blood, 1, and which send large 
vessels to the upper extremities, 2. The rather irregu- 
lar manner in which these branches are given off from 
the arch is here correctly represented. The branches 
going to the left side of the head and the left upper 
extremity arise separately, while, on the right side, they 
arise from the aorta as one branch and afterwards 
divide. 
In the abdominal cavity, just below the diaphragm, 
the aorta gives off a large branch which divides into 
three branches; these supply the liver, 4, and the stom- 
ach, pancreas, and spleen, 5. Lower down is a single 
branch, which goes to the small intestine. Still lower 
are the two arteries, 6, which go to the kidneys. Below 
these is a branch which supplies blood to the large intes- 
tine. Thus the aorta is the great central artery of the 
body. It is deeply seated in the thoracic and abdominal 
cavities, and is well protected from injury. The veins 
are placed side by side with the arteries. 
Aids to the Circulation. Exercise is one of the greatest 
aids to the circulation. It not only causes the heart to 
beat faster and thus hastens the flow of blood, but it is 
a direct aid to the movement of blood in the veins. 
When a vein is filled, the blood cannot flow backward 
toward the capillaries on account of the valves ; there- 
fore, if the muscles be made to contract and thereby 
press upon the veins, the blood will be pushed onward. 
When the muscle relaxes, the vein is again filled with 
blood coming from the capillaries. More muscular ex- 
ercise will again hasten on the blood to the heart. The 
surface of the body should be kept warm, because cold 118 
THE ESSENTIALS OF HEALTH. 
contracts the blood vessels, and thus interferes with a 
free circulation. Very tight clothing is also a hindrance 
to the free flow of the blood. The clothing may fit 
closely and yet not so tightly that the flow of the blood 
in the veins is impeded. 
THE EFFECTS OF ALCOHOL AND TOBACCO 
Alcohol and the Heart. The heart is an involuntary 
muscle ; it keeps steadily at work, whether we “ will ” to 
have it or not. While it is not under the control of the 
will, yet, like all other muscles, it is controlled by nerves. 
Experiments have proved that there are nerves which 
act as brakes to the heart, holding it in check and 
regulating its beat. 
In a later chapter will be stated more fully how alco- 
hol tends to benumb, or partially paralyze, the nerves. 
So alcohol tends to paralyze the nerves that hold the 
heart in check. As a result, the heart beats faster. 
One result of this extra work is that the muscles of the 
heart become thickened and the cavities enlarged. The 
heart is not in repose long enough to have its over- 
worked tissues fully nourished, and so a process of de- 
generation begins. Particles of fat, or oil, take the 
place of the muscle. At first, this is very slight; but 
gradually a change occurs, until much of the worn-out 
muscle disappears and fatty tissue takes its place. 
The heart now becomes very weak, hardly able to 
force the blood through its proper channels. The cir- 
culation is poor, the extremities are swollen, and there 
is difficulty in breathing. The physicians call this ALCOHOL AND TOBACCO. 
119 
trouble. “ fatty degeneration of the heart.” The heart 
becomes weaker and weaker, until, suddenly, it is un- 
able to do its work longer, and death occurs. This is 
no idle story. The effect of alcoholic beverages is so 
marked that fatty degeneration of the heart is often 
called, by physicians, the “ whiskey heart,” or the “ beer- 
drinker’s heart.” 
It is well to remember that the strongest drinks are 
not necessarily required to produce these changes. The 
extra amount of flesh found in those who use ale and 
beer freely is of this fatty nature ; and a fatty heart is 
no more than we would expect to find in such a fleshy 
body. Physiologically, alcohol over-works the heart; 
anatomically, alcohol changes its structure. Alcohol 
never imparts life-giving power, while it often causes 
death. 
Alcohol and the Arteries. The same changes already 
mentioned, as occurring in the muscular tissue of the 
heart, may also take place in the muscular tissue of the 
walls of the arteries. The cells become weakened by 
the deposit of fat within them, and thus the whole wall 
loses some of its strength. This makes the walls more 
liable to rupture, and is one of the predisposing causes 
of apoplexy. 
Alcohol and the Smaller Vessels. The walls of the 
smaller arteries consist largely of muscular tissue. 
This tissue is continuously kept in a partially contracted 
condition, in order that the walls may be more firm. 
The muscular tissue is under the control of minute 
nerves, called the vaso-motor nerves. These nerves are 
capable of making the muscle contract firmly, thereby 
diminishing the size of' the vessel; while if they cease 120 
THE ESSENTIALS OF HEALTH. 
to act, from any cause, the muscle relaxes and the size 
of the vessel is greatly increased. 
The small arteries are said to have “ tone ” when 
these nerves exert their power, and keep the muscle in 
its usual condition of moderate contraction. The walls 
of the smaller arteries, therefore, are constantly in a 
state of moderate contraction. The effect of alcohol is 
to partially paralyze these vaso-motor nerves, so that 
they cease to exert their full power on the muscular 
tissue. If a small dose of an alcoholic beverage be 
taken, the effect may be slight and only temporary, as 
illustrated in the flushing of the face ; if not repeated, 
recovery may be complete ; but a continuation of such 
doses causes the paralysis to become more permanent, 
and the nerves to lose their power of controlling the 
size of the blood vessels. 
Not only the red nose and the red eyes of the con- 
firmed drinker, but the reddened face and distended 
capillaries often seen in the moderate drinker, are in- 
dications of the paralysis of the vaso-motor nerves. 
The “tone” has disappeared from the walls of the 
blood vessels; the muscular tissue is becoming or has 
become permanently relaxed, and the vessels are con- 
stantly in a distended condition. But the nose, eyes, 
and other portions of the face are not the only places 
where this congestion occurs. It exists in the mucous 
membranes of the body to a large extent; while many 
of the organs and tissues are also in this chronic con- 
gested condition. 
If such a condition of things were to arise from any 
other cause the individual would be greatly worried and 
would seek medical advice at once. But he either does ALCOHOL AND TOBACCO. 
121 
not realize that the alcohol is the cause of all the aches 
and pains he feels, or cares too much for it to give it up, 
and thus he continues his downward course. We in- 
sist that the man who is under the influence of powerful 
poison is a sick man, no matter whether he be intoxi- 
cated, or simply indulges in moderate doses. In either 
case his system is affected, and he should be under the 
careful attention of a competent physician. 
Such men need medical advice and restorative reme- 
dies far more than the vast majority of those who are 
regular patrons of the physician’s office. The burning 
of the stomach, the darting neuralgic pains, the head- 
aches, all these and many other ailments indicate the 
tremendous damaging power of this poison. Nothing 
short of a strong resolve to use no more alcoholic liquors 
will answer. To attempt to stop gradually is a very 
poor plan ; but even a firm resolve, the breaking away 
from old associates, and the forming of new, may not 
prove sufficient. The old appetite remains. It is here 
that the competent physician can accomplish much. 
He can aid nature in her efforts to restore the body to 
health. He can aid in building up the tissues, in cor- 
recting the congested and inflamed organs, and thus 
banish from the system an appetite as unnatural as it is 
injurious. 
But how can all this be prevented ? How can we all 
escape the strong power of alcohol ? Simply by refus- 
ing to take the first glass of any kind of alcoholic 
drink. 
Tobacco and the Heart. Tobacco affects the heart 
largely through the action of the nicotine on the nerv- 
ous system. A prolonged use of tobacco frequently gives 122 
THE ESSENTIALS OF HEALTH. 
rise to a particular affection known as the “ tobacco 
heart.” The author has seen a strikingly large number 
of these cases in young men between fifteen and twenty 
years of age. The heart is irregular in its action and 
sometimes beats with great force. This is often accom- 
panied with a sensation of weakness or great anxiety. 
There are occasional attacks of dizziness, shortness of 
breath, nausea, and vomiting. At times there is intense 
pain in the region of the heart. Tobacco will not make 
so serious changes in the structure of the heart as have 
been described under alcohol, yet it is capable of doing 
immense harm. 
Within a few years there have been well-known in- 
stances among our most prominent statesmen, where 
death was instantaneous, as a result of disease of the 
heart from the long-continued use of tobacco. With 
such a history, tobacco should no longer be regarded as 
a luxury, but rather as a slow poison capable of accom- 
plishing an enormous amount of damage. 
1. Name the four parts of the circulatory apparatus. 
2. Describe the heart, and its position in the chest. 
3. Describe the cavities of the heart and the valves between them. 
4. Give the course of the blood through the heart. 
5. Which ventricle is the stronger? Why? 
6. How many sounds of the heart ? Describe them. 
7. "What causes the pulse ? 
8. What is the structure of the walls of the arteries? 
9. How do the veins differ from the arteries ? 
10. How rapid is the circulation ? 
11. Give some of the effects of alcohol on the smaller vessels. 
12. How does tobacco affect the heart ? 
QUESTIONS. SUGGESTIONS TO TEACHERS. 
123 
SUGGESTIONS TO TEACHERS. 
1. The Heart. Procure the heart of a calf or sheep at 
the market. Preserve the large vessels at its base. Wash 
in water and wipe dry. Call attention to the shape; to the 
auricles ; and to the ventricles. Hold the heart obliquely, 
as in Figs. 29 and 30, thus showing its position in the body. 
2. Circulation through the Heart. This can be illus- 
trated by pointing to the parts in order, thus : right auri- 
cle, right ventricle, left auricle, left ventricle, according to 
Fig. 31. The right side of the heart can be told from the 
left by remembering that the left ventricle projects around 
to form the point of the heart ajid a small part of the ante- 
rior surface. The walls of the right side are also thinner. 
3. The Arteries. Notice the size and the thick walls 
of the aorta. It keeps open, as a circular tube. Lift the 
heart by the aorta, and notice the elasticity of the artery. 
4. The Veins. These will be collapsed, with thinner 
walls, which are not elastic like the aorta. 
5. Walls of the Ventricles. Cut the heart open trans- 
versely about half way back from the apex, to illustrate 
Fig. 32. The firm partition between the ventricles, the 
relative thickness of the walls, and the smooth lining- 
membrane, will be brought to view. 
6. Valves. Cut away the ventricles close to the auri- 
cles. Notice the thin membranes which are between the 
auricles and ventricles ; these are the valves. 
7. Pericardium. By making arrangements at the mar- 
ket, a heart may be procured, surrounded by its sac. This 
is the pericardium. Cut it open with scissors. A small 
amount of fluid may escape. Notice how smooth is the 
lining of this membrane. 124 
THE ESSENTIALS OF HEALTH. 
CHAPTER XII. 
RESPIRATION. 
The Nasal Cavities. The nostrils are the proper chan- 
nels through which the air should reach the lungs. The 
nose has at least three important functions to perform 
in connection with respiration: these are to warm, to 
moisten, and to filter the inspired air. 
The first of these is evidently very important; for, if 
the cold air of winter should be brought directly in con- 
tact with the tissues of the throat and larynx, inflam- 
mation would be likely to follow, causing sore throat, 
hoarseness, and loss of voice. The tissues of the nasal 
cavities are so well supplied with blood that they 
are capable of warming the air as it passes over them, 
until its temperature more nearly equals that of the 
body. 
The second function is likewise important: there is 
at least a pint of serum secreted every twenty-four hours 
by the mucous membrane lining the nose: the inspired 
air passes through the nose, takes up this moisture, and 
becomes saturated with it. That the inspired air takes 
moisture from the tissues is easily proven by breathing 
through the mouth for a short time. The throat soon 
becomes dry, and swallowing is difficult. The cells cov- 
ering much of the lining membrane of the nose are of RESPIRATION. 
125 
the ciliated variety, as represented at 4, in Plate I. The 
cilia catch the particles of matter found in dust and 
smoke, and in the ordinary inspired air. In this way the 
nose acts as a filter. 
Mouth Breathing. When breathed through the mouth, 
the air is but little warmed, is only slightly moistened, 
and is not filtered. Mouth breathing brings the air in 
contact with the larynx, trachea, and bronchial tubes, 
scarcely changed. It is still cold, dry, irritating, and, 
as a result, more or less inflammation is produced. 
Inflammation of the throat, enlarged tonsils, chronic 
hoarseness, and coughs are some of the affections which 
result from the pernicious habit of breathing through 
the mouth. Nature intended we should breathe through 
the nose, and a number of evils will result if we fail in 
so doing. If it be impossible to get air through the 
nose, a physician should be consulted that the difficulty 
may be removed. Early attention to these conditions 
would do much to prevent the catarrhal affections so 
prevalent in this country. 
The Larynx. After the inspired air has passed through 
the nose, it enters the upper part of the pharynx. From 
here it passes down the throat, until opposite the base 
of the tongue, where it reaches the larynx. The larynx 
is situated at the upper and front part of the neck. It 
contains the parts necessary for the production of the 
voice. The expansion on the front of the larynx, so 
much more prominent in men than in women, is com- 
monly known as Adam’s apple. The larynx is com- 
posed of cartilages, lined with a mucous membrane. 
About the middle of its interior are two strong bands 
of elastic tissue, called the vocal cords. They extend 126 
THE ESSENTIALS OF HEALTH. 
from the front to the back of the laryngeal cavity. The 
space between them, through which the air passes, is 
FIG. 37. 
FIG. 38. 
Fig. 37. The position of the vocal cords during inspiration : the 
rings of the trachea are seen between the vocal cords. 
Fig. 38. The position of the vocal cords when uttering a high note : 
v c, vocal cords ; E, epiglottis. 
called the glottis: this opening varies in size according 
Fig. 39. A diagram illustrating how the vocal cords are seen, as in 
Figs. 37, 38 : m, a circular mirror held, by a band, to the forehead of the 
operator; l, a lamp, placed at the side of the patient’s head, to throw 
light on the large mirror, M ; m, a small mirror held in the back of the 
throat of the patient : e, epiglottis ; v c, location of the vocal cords. RESPIRATION. 
127 
to the tension of the vocal cords. This is well illus- 
trated by referring to Figs. 37 and 38. During inspira- 
tion the vocal cords are quiet, and the opening between 
them is large, as in Fig. 37; but when sounds are pro- 
duced the vocal cords come together and the glottis is 
narrowed. The higher 
the notes, so much the 
tighter will the vocal 
cords be drawn, and so 
much the narrower 
will be the glottis, as 
in Fig. 38. Figs. 37 
and 38 are representa- 
tions of the interior of 
the larynx, as seen 
with the laryngoscope. 
The laryngoscope 
consists of a small mir- 
ror attached to a long 
handle. To use it, the 
mouth is opened, the 
tongue drawn forward, 
and the mirror intro- 
duced as shown in 
Fig. 39. Direct sun- 
c5 
light, or artificial light, 
is reflected from a large 
mirror to the smaller one which is in the back part of 
the throat. The small mirror reflects the light down 
the larynx so that its interior becomes brilliantly illu- 
minated. A picture of the larynx is thus formed in the 
mirror, to which the observer directs his eye. 
Fig. 40. A diagram illustrating the 
position and use of the epiglottis : N, na- 
sal passages ; M, mouth ; 0, oesophagus ; 
l, larynx; t, tongue; the feathered ar- 
rows represent the passage for air ; the 
plain arrows, the passage for food. 128 
THE ESSENTIALS OF HEALTH. 
The Epiglottis. The entrance to the larynx is pro- 
tected by a valve, or lid, called the epiglottis. During 
respiration the epiglottis is directed upward, so that 
the larynx is open; but during the act of swallowing, 
the epiglottis shuts tightly down over the larynx, pre- 
venting the entrance of any solid or liquid. Occasion- 
ally, however, a particle of food “ goes the wrong way ” 
and slips into the larynx, when a violent cough is neces- 
sary for its removal. Fig. 39 gives a correct representa- 
tion of the parts under discussion. Fig. 40 is a diagram, 
illustrating more clearly the location and function of the 
epiglottis. 
The Trachea. The trachea, commonly known as the 
windpipe, consists of a number of rings of cartilage. 
These rings are not quite complete at the back of the 
trachea; however, the tube is completed by a thin mem- 
brane. The rings are placed one over the other, sepa- 
rated only by a narrow membrane. They keep the 
trachea from collapsing ; thus always insuring a free 
passage for the air. The tube is lined, its whole length, 
with a mucous membrane. About opposite the upper 
part of the sternum, the trachea divides into two 
branches, called the bronchi, one branch going to each 
lung. 
The Bronchi and the Air Cells. After entering the 
lungs, the bronchi divide again and again, until they 
are very minute in size. They are everywhere lined 
with a mucous membrane. A study of Pig. 41 will 
make these facts more simple. At 1, is the epiglottis, 
standing guard over the entrance to the air passages 
below; at 2, is the larynx, or voice box; at 3, is the 
trachea with its rings of cartilage; at 4, is the right RESPIRATION. 
129 
lung, so drawn that the bronchial tubes can be seen 
within it. 
After these have become very small, from their re- 
peated divisions, they terminate in a collection of minute 
Pig. 41. The respiratory apparatus : (1) the epiglottis ; (2) the larynx ; 
(3) the trachea ; (4) the right lung ; (5) the left lung. 
sacs, called air cells. The walls of these air cells are 
very thin and highly elastic. They can be distended by 
slight force, and when the force is removed, they can at 
once resume their former size. Fig. 42 shows a terminal 130 
THE ESSENTIALS OF HEALTH. 
bronchial tube with its air cells. If we bear in mind that 
these air cells have elastic walls, it is easy to imagine 
how they could be inflated, like so many rubber sacs, 
by forcing air into the tube, at 
1. This is practically about 
what occurs during an ordinary 
respiration. 
The inner surface of these air 
cells is exposed to the air which 
enters the lungs. The amount 
of surface thus exposed is very 
great, being estimated to be at 
least fourteen hundred square 
feet. Surrounding the walls of 
the air cells is a dense network 
of capillary blood vessels. Thus 
the blood itself is separated from 
the air only by an extremely 
thin membrane. It is here, in the air cells, that the 
changes occur which transform the dark venous blood 
into the bright arterial blood. 
The Pleura. The pleura is a double membrane, cov- 
ering the inside of the thoracic cavity and the lungs. 
One membrane is closely fastened to the inner walls 
of the chest, while the other covers the surface of the 
lungs. The space between these membranes is called 
the pleural cavity. The pleura secretes a fluid, so that 
its two surfaces may move against each other easily and 
without friction, as they do in ordinary breathing. An 
inflammation of this membrane is called pleurisy ; it is 
extremely painful, because each time a breath is taken 
the lungs expand, causing the inflamed membrane cov- 
Fig. 42. (1) the end of a 
small bronchial tube ; (2) air 
cells ; (3) some of the air cells 
cut open, showing free passage 
to them from the bronchial 
tubes. RESPIRATION. 
131 
ering the lungs to move against another inflamed mem- 
brane lining the walls of the chest. 
The Lungs. The two lungs are situated in the tho- 
racic cavity, one in either side of the chest. Owing to 
the amount of elastic tissue in the air cells, the lungs have 
great elasticity. When removed from the body they 
appear completely collapsed; still they float in water on 
account of the air yet remaining in the air cells. When 
in this collapsed condition, if a tube be placed in the 
trachea the lungs may be inflated by blowing into the 
tube or by forcing air in with a pair of bellows. After 
the inflation, it is only necessary to remove the tube or 
allow the air to escape through it, when the lungs will 
immediately collapse again. Thus it is easily proved 
that if some force be applied to send air into the lungs, 
the elastic tissue in the air cells will stretch like rubber; 
and that as soon as the force is removed the elastic tis- 
sue will return to its former condition. 
Why Air enters the Lungs. The mechanism of res- 
piration is not unlike that of a pair of bellows. When 
the handles are raised the inside of the bellows is made 
larger, and the air rushes in to fill the extra space. 
The chest is a tight box, with only one opening, and 
that at the top, — the larynx. If this box be suddenly 
enlarged the air will rush in through the opening; this 
is called inspiration. When the box ceases to enlarge, 
no more air enters. Immediately all the parts that were 
under a tension to enlarge the box return to their for- 
mer condition. Thus the box is made smaller and the 
hir rushes out of the opening at the top ; this is called 
expiration. From this we conclude that air enters the 
lungs because the chest is made larger; and that it leaves 132 
THE ESSENTIALS OF HEALTH. 
the lungs because the chest is made smaller. Before 
discussing this subject more in detail, it will be well to 
fix in the mind the shape of the thoracic cavity, its con- 
tents, and the relation of certain organs to each other. 
Fig. 43. The position of the lungs, and their relation to certain organs : 
(1) the trachea ; (2) the clavicle ; (3) the ribs ; (4) the lungs; (5) a dark 
curved line, showing the position of the heart; (6) the diaphragm, extend- 
ing in a curved direction from one figure to the other; (7) the liver; 
(8) the stomach ; (9) the sternum. 
A reference to Pig. 43 will illustrate these points. The 
lungs rise above the collar bone, 2, to form the apex of 
the chest: below, they rest upon the curved diaphragm, 
6, which divides the thoracic from the abdominal cavity. RESPIRATION. 
133 
The relative position of the heart is shown by the curved 
line, 5. Pressing up against the under surface of the 
diaphragm, on the right side is the liver, 7, while on the 
left side is the stomach, 8. By glancing at this figure 
it is easily understood that if the lower ribs be brought 
tightly together from any cause, as bv tight lacing, the 
stomach and liver will be forced 
up against the diaphragm. As 
a result of this it would be ex- 
tremely difficult for the dia- 
phragm to become straighter 
or lower, or, as illustrated in the 
figure, for the line 6 to become 
shorter. The application of this 
fact will be seen later. 
Inspiration. The chest is en- 
larged first, by the raising of the 
ribs. By the contraction of cer- 
tain muscles the ribs are moved 
upward and outward; this 
enlarges the chest anteriorly and 
laterally. That the chest is 
enlarged between the sternum 
and the spinal column is readily seen by referring to 
Fig. 44. S C represents the spinal column, and S, the 
sternum. After expiration, when the chest is at rest, it 
is noticed that the ends of the ribs attached to the ster- 
num, S, are much lower than the ends attached to the 
spinal column ; this fact is also illustrated in Figs. 29 
and 43. Now in Fig. 44 it is evident that if the ribs, 
R, are raised by any force, they will carry the sternum 
with them to the point ST. It is also evident that the 
Fig. 44. A diagram illus- 
trating liow the thoracic cavi- 
ty is enlarged during inspira- 
tion : s c, spinal column ; s t, 
r i, and d m, illustrate the 
position of the sternum, ribs, 
and diaphragm, during inspi- 
ration ; s, R, and D, their 
position during expiration. 134 
Tilt: ESSENTIALS OF HEALTH. 
distance between S C and S T is much greater than that 
between S C and S. Therefore we conclude that rais- 
ing the ribs increases the size of the chest from front 
to back. Because the ribs are curved, the chest is 
enlarged from side to side when they are raised. * 
Second, the chest is enlarged by the contraction of 
the diaphragm. Attention has already been called to 
this thin muscle. When it relaxes it is in the form of 
a vaulted partition, with its rounded portion rising into 
the cavity of the chest, as represented in Fig. 43, and at 
D, Fig. 44. When the diaphragm contracts, it shortens, 
assuming more nearly a straight line, as in D M, Fig. 
44; thus the convexity becomes greatly diminished. 
The contraction of the diaphragm, therefore, makes it 
descend toward the abdomen ; this must enlarge the 
thoracic cavity from above downwards. Thus we con- 
clude that in ordinary, quiet breathing we do not draw 
the air into the lungs ; the air rushes in, without aid, 
to fill the chest, which is made larger by the elevation 
of the ribs and the contraction, or lowering, of the 
diaphragm. 
Expiration. Ordinary expiration occurs without the 
aid of muscles. By the relaxation of the muscles of 
the chest, the ribs fall back to their natural places. 
The relaxation of the diaphragm causes it to protrude 
again into the chest, aided by the pressure of the ab- 
dominal organs from beneath pushing up against it. 
The distended elastic tissue of the air cells now seeks to 
return to its natural condition, thus diminishing the size 
of the air cells, and, consequently the size of the whole 
lungs ; the thoracic walls keep in contact with the dimin- 
ishing lungs, and thus the air rushes out of the larynx. RESPIRATION. 
135 
Respiration. Respiration is the function by which 
oxygen is introduced into the body, and carbonic acid 
removed from it. 
Ordinary breathing is involuntary. We breathe when 
we are not thinking of it, and breathe as regularly when 
asleep as when awake. But respiration is also volun- 
tary, for it is possible to breathe more slowly or more 
rapidly than usual, for a short time. By taking advan- 
tage of this fact the respiratory muscles can be greatly 
strengthened. Like other muscles they can be devel- 
oped and strengthened by exercise. Singing and speak- 
ing call for a full exercise of these muscles, and when 
properly employed they are very beneficial. 
The imitations of crying, laughing, and the like are 
voluntary respiratory movements, principally spasmodic 
contractions of the diaphragm. Even these movements 
may be involuntary ; the spasmodic action of the dia- 
phragm may go beyond control, so that it is impossible 
to cease laughing or crying. 
Number of Respirations. The number of respirations 
should be about one to every four beats of the pulse. 
As the average pulse of the male adult is about 70, so 
the number of respirations should be about 18. But 
this is influenced by many conditions ; as, the size of the 
lungs,' the condition of the air, exercise, singing, speak- 
ing, and many other circumstances. The number can- 
not, however, be lowered for any considerable length of 
time; the demands of the system for more oxygen, 
and for an escape of the carbonic acid are so great that 
it is impossible to resist them. 
Sounds of the Chest. When the air rushes in and out of 
the lungs, peculiar sounds are produced. These are 136 
THE ESSENTIALS OF HEALTH. 
easily changed by unhealthy conditions of the lung 
tissue ; the air may not enter a portion of the lungs ; 
it may enter a cavity; or it may pass over a membrane 
either too dry or too moist. Any such departures from 
health cause a change in the normal sounds. A careful 
study of these sounds enables the physician to determine 
the healthy or unhealthy condition of the lungs. By 
their aid, he can understand the nature of the disease, 
and how far it has progressed. 
The Inspired Air. Each inspiration brings about 
twenty cubic inches, or two thirds of a pint of air into 
the lungs. This air only extends down the lungs a 
short distance, probably not much below the larger 
bronchial tubes. If the air should remain here it would 
be of little use. But the law of the diffusion of gases is 
such that the gases — the oxygen and the carbonic acid 
— which are in the bronchial tubes and the air cells 
freely and rapidly intermingle. The inspired air brings 
oxygen to the red corpuscles of the blood. 
The Expired Air. If the expired air be collected and 
examined, it will be found to differ from the inspired 
air in the following particnlars : 1. It has lost oxygen. 
The expired air contains nearly five per cent less oxygen 
than the atmospheric air. 2. It has gained carbonic 
acid. The expired air contains nearly a hundred times 
more carbonic acid than the atmospheric air. This gas 
represents one of the waste products of the body, and 
must be removed. 3. It has absorbed water. The expired 
air is saturated with watery vapor. This is easily shown 
by breathing on a mirror, or on any polished surface. 
4. It contains organic matter. The amount is usually 
very slight, and not easily detected. If it be in excess RESPIRATION. 
137 
it imparts a perceptible odor to the breath, which may 
be both offensive and poisonous. Even with the ordi- 
nary amount, its presence is easily detected if a number 
of persons be confined in a small room where there is 
poor ventilation. Under such circumstances the odor 
becomes very offensive, remaining in the room for hours 
after it is vacated by the people. 5. The expired air is 
usually warmer. To be more exact, it is generally 
about the temperature of the body, being unaffected by 
the variable temperature of the inspired air. 
The Lungs as Excretory Organs. An excretion consists 
of waste products that are useless or injurious to the 
body, and must be separated, or thrown off, from it. Cer- 
tain organs are known as the excretory organs, because 
of the work they accomplish in this line. Viewed in this 
light, the lungs must be regarded as excretory organs, 
as they are constantly throwing off from the body car- 
bonic acid and other impurities. 
ALCOHOL, TOBACCO, AND THE LUNGS 
Alcohol. Persons who are in the habit of using alco- 
holic beverages seem to be especially liable to colds, 
and to bronchial affections. Probably one explanation of 
this is that often the circulation in such persons is poor, 
and the heart’s action affected. As a result, there is a 
slight, but constant congestion of the lungs ; that is, too 
much blood is in the lung tissue. In some cases, late 
hours and bad habits of life increase the effects just 
noted. 
It is certainly true that an inflamed condition of the 
throat and larynx is generally found in those addicted 138 
THE ESSENTIALS OF HEALTH. 
to strong drink, while attacks of bronchitis are not 
infrequent. Another fact stands very prominent. It 
is this: the probability of recovery from an attack of 
pneumonia is immensely less in the intemperate than 
in the temperate. We believe the great majority of 
physicians, everywhere, will testify to the truth of this 
statement. It is generally recognized that the contin- 
ued use of strong drink undermines the power of the 
body to resist disease, and in no disease is it more 
marked than in the one already mentioned. 
Tobacco. Tobacco especially affects the upper air pas- 
sages. The irritating qualities of the smoke keep the 
throat congested, so that smokers suffer from a special 
variety of catarrh, known as the “ smoker’s sore throat.” 
The larynx is often in sympathy with the throat affection, 
and there is a dry, hacking cough. 
QUESTIONS. 
1. Give three important functions of the nose. 
2. State why these are so important. 
3. Why is breathing through the mouth injurious ? 
4. What is within the larynx? 
5. Where is the epiglottis ? What is its use ? 
6. Describe the trachea. 
7. Describe the air cells. What changes occur in blood here ? 
8. State some facts about the pleura. 
9. How would you prove that the lungs have great elasticity? 
10. Give the mechanism of respiration. 
11. How is the chest enlarged in inspiration? 
12. What is respiration ? Is it voluntary ? 
13. How many respirations per minute? 
14. How does the expired air differ from the inspired? 
15. Give some of the ill effects of alcohol and tobacco. SUGGESTIONS TO TEACHERS. 
139 
SUGGESTIONS TO TEACHERS. 
1. The Respiratory Apparatus. Procure the lungs of a 
sheep at the market. Wash in water, and wipe carefully. 
Call attention to the trachea, the bronchi, and the lungs. 
2. Inflation of the Lungs. Insert a tube of any kind 
into the trachea. Tie the trachea tightly about it. Breathe 
into the tube and so force air into the lungs, thus making 
them expand as in inspiration. Remove the mouth and 
the lungs will collapse, as in expiration. A pair of bel- 
lows is the best for inflating the lungs. 
3. Lung Tissue will Float. Cut off a small piece of the 
lung tissue and throw it into water; it will float, showing 
that air still remains in the air cells. Press the pieces 
in the hands to force out the air; still it will not sink. 
4. The Trachea is always Open. Cut the trachea trans- 
versely. Try to compress it, and thus illustrate how the 
rings of cartilage keep it open so that it cannot collapse*. 
Notice that the rings of cartilage are incomplete behind; 
and that a membrane completes them. 
5. The Bronchi. Cut away the lung tissue which is 
near the lower end of the trachea. First notice how the 
trachea divides into two bronchi, before entering the lungs; 
then notice how these divide into the bronchial tubes. 
6. The Larynx. By previous arrangement at the market, 
a complete larynx may be procured. This will show the 
epiglottis, the vocal cords, and the hard cartilaginous walls. 
7. Respiratory Acts. Have the pupils illustrate inspira- 
tion, expiration, and a complete respiration. 
8. Respiration, Voluntary and Involuntary. Show that 
respiration is voluntary by fast, then slow breathing; this 
soon becomes tiresome. 
9. Watery Vapor. Breathe on any polished surface, and 
notice the condensed vapor. 140 
THE ESSENTIALS OF HEALTH. 
CHAPTER XIII. 
VENTILATION. 
Amount of Air Inhaled. In the preceding chapter it was 
stated that about twenty cubic inches of air are inhaled 
at each inspiration. Based on this statement, and mak- 
ing due allowances for muscular exertion by which 
breathing is increased in frequency, it is safe to say 
each person uses at least three hundred and fifty cubic 
feet of air, daily, in respiration. 
Oxygen supports Life. After breathing the air once it 
still contains considerable oxygen ; after breathing this 
same air over and over again the amount is so reduced 
that the animal dies from suffocation. In the case of man, 
if the amount of oxygen in the air be reduced one half, 
breathing continues with great difficulty. A certain 
amount of oxygen in the air is necessary to support 
human life; while a much less amount of oxygen is 
required to support life in some of the lower animals. 
It requires more oxygen for the burning of a candle 
than it does to support life, for a short time. Advantage 
is often taken of this fact to test the safety of entering 
a well, a vault, or an underground passage. A lighted 
candle is lowered into the cavity; if a sufficient amount 
of oxygen be present, the candle will continue to burn ; 
if not, it will be immediately extinguished. If the can- VENTILATION. 
141 
die continues to burn it will be safe for the man to enter 
the enclosure, for the reason that more than enough 
oxygen is present to support human life. 
Carbonic Acid is a Poison. Each respiration not only 
takes oxygen from the air, but it also gives to it a quan- 
tity of carbonic acid and other deleterious ingredients. 
Hence it is injurious to breathe the same air, even for 
the second time. If the air be poor in oxygen, it will 
contain a large amount of carbonic acid. As this gas 
is heavier than the air, it will fall when confined in a 
small space and left undisturbed. The air which is the 
least capable of supporting life is then found at the low- 
est level. For this reason the air at the bottom of the 
well is much more poisonous than the air nearer the 
top. 
An animal placed in a closed space will absorb from 
the air a certain amount of the oxygen, and will give 
off carbonic acid. Soon the surrounding atmosphere 
will be so saturated with carbonic acid that no more of 
it will pass from the body ; this is according to certain 
laws respecting the diffusion of gases; therefore the 
carbonic acid is retained in the blood of the animal, 
causing its speedy death. This carbonic acid poisoning 
may occur while there is yet enough oxygen remaining 
in the air to support life. 
From what has been said, we conclude that oxygen is 
necessary to life, and that an insufficient amount of it 
in the air will cause death. We also conclude that if 
the carbonic acid be not removed, it may accumulate in 
the air sufficiently to cause death. The air we breathe, 
therefore, should have a certain amount of oxygen, and 
should not have an excess of carbonic acid. 142 
THE ESSENTIALS OF HEALTH. 
A person is warned when needing more oxygen and 
less carbonic acid, unless as the result of some acci- 
dent. Headaches, restlessness, heaviness, and drowsi- 
ness result from a deficiency of oxygen and a surplus 
of carbonic acid. Unless the system is freely supplied 
with the former and readily disposes of the latter, the 
vital forces become lowered and the whole body predis- 
posed to disease. 
An Abundance of Air Necessary. The above facts are 
given especially that we may appreciate the necessity 
for an abundance of fresh air. It does not necessarily 
follow that the person must be either out of doors or in 
a very large room; but it does follow that, under all 
circumstances, an abundant supply of fresh air should 
be continuously within reach of the body. 
Pure Air. The fact that the air is cold, and feels fresh 
to the face, is not proof that it is pure ; currents of air 
may be loaded with poisons. Pure air contains the 
proper proportion of oxygen, and is free from poison- 
ous gases and disease germs. Out-door air is not neces- 
sarily pure, as some sewer gas or decaying animal matter 
may be near. Yet, as a rule, owing to the law of the 
diffusion of gases, out-door air is the purest. An abun- 
dance of pure air is what is demanded. 
It is not always possible to tell when the air is pure; 
for the best ordinary test we have is the sense of smell. 
Upon entering a room, if the air seems “ close ” it is suf- 
ficient proof that better ventilation is needed. After re- 
maining in a close room the nose becomes accustomed 
to the odor and the closeness is not noticed, so the ques- 
tion of ventilation should be attended to as soon as the 
room is entered. VENTILATION. 
143 
A Deficiency of Air Dangerous. Many cases are on 
record where persons have been poisoned by repeatedly 
breathing the same air. This is not likely to occur in 
our houses, because there are so many crevices about 
the windows and doors that enough fresh air enters. 
But in the holds or cabins of ships, and in the deep 
cells of prisons, some terrible results have occurred. 
Many writers have referred to the “ black hole of Cal- 
cutta ” as an illustration of this fact. In a small room 
with only two narrow windows, there were confined one 
hundred and forty-six prisoners; these persons were 
obliged to breathe the same air over and over again, 
for the windows were altogether too small to allow a 
sufficient amount of fresh air to enter. In eight hours 
one hundred and twenty-three of the prisoners were 
dead, while those whose lives were spared endured 
great suffering. 
Many rooms, built to accommodate large numbers at 
a time, have an insufficient supply of fresh air, as, for in- 
stance, schoolrooms, lecture-halls, and churches. While 
such a deficiency may not be enough to cause death, yet 
the effect on the body is marked and harmful. Drowsi- 
ness, with a dull, heavy headache, often results from a stay 
in such a poorly ventilated room. The listless and sleepy 
appearance of many a scholar is simply the result of im- 
pure air, rather than of a dull mind. “ Break open the 
window! ” shouted a noted divine, in the midst of his 
discourse, as he saw many in his congregation asleep. 
He knew that the most brilliant speaker could not over- 
come the drowsy effects of impure air. 
If it becomes necessary to spend a considerable time 
eacli day in a poorly ventilated or overcrowded room the 144 
THE ESSENTIALS OF HEALTH. 
whole body is soon affected. Living in poorly ventilated 
rooms enfeebles the whole body; the appetite fails, the 
red corpuscles are reduced in number, the skin becomes 
colorless, and the whole system shows that it is suffer- 
ing from too little oxygen and from too much carbonic 
acid. Colds and coughs are frequent; and the system 
has only slight power to resist disease of any kind. 
The whole condition is one of “ oxygen starvation ” 
and carbonic acid poisoning. 
The Proper Amount of Air. It has been stated that an 
abundance of pure air is necessary. It is better to say 
that an over-abundance is necessary, so that if any 
error be committed it may be on the safe side. The 
supply of fresh air required for a room depends largely 
on the number of persons in the room; for it is evident 
that a hundred persons will require a hundred times as 
much air as one person. 
Then, too, the presence of fires in the room must be 
considered. The burning gas consumes much oxygen 
and gives off carbonic acid. For this reason a crowded 
hall, on a cold winter’s evening, with heavy fires and 
lighted gas, requires much more ventilation than when 
a small company is assembled on a warm summer’s day. 
As it would cause discomfort to raise the windows and 
open the doors during the winter time, it follows that 
some system of ventilation is absolutely necessary for 
all places where persons are likely to assemble. 
How to Obtain Pure Air. How to obtain an unfailing 
supply of fresh, out-door air in our rooms is the con- 
stant study of those who plan homes and public build- 
ings; Years ago this subject received no attention 
whatever. This was partly due to the fact that the VENTILATION. 
145 
method of heating the houses was far different from 
that used at the present day. The open fireplaces made 
a constant change of air, while the cracks about the 
doors and windows furnished avenues through which 
the fresh air entered the rooms. 
A furnace gives good ventilation, because as the warm 
air enters the room from the registers the cold air 
escapes through ventilators in the wall near the floor; 
thus a constant current of air is established. Great 
care should be exercised to see that the cold air-flue of 
the furnace receives its supply from clean surroundings. 
If the out-door air, entering the flue is near decaying 
animal or vegetable matter, or an imperfect sewer, then 
the impure air might be conveyed into the building, 
producing severe and perhaps fatal sickness. 
If the rooms be heated by a furnace, the air should be 
moistened by having it pass over a dish of water. A fail- 
ure to do this results in the necessity of breathing very 
dry air, which is decidedly injurious. The open grates of 
modern days are good ventilators. An ordinary stove 
is a means of ventilation, for as the draught passes 
through it and up the chimney, fresh air comes in 
through the opening of doors and the crevices of the 
windows to take its place. 
Attention should always be given to the ventilation of 
the sleeping rooms. One third of our entire lives is 
spent in these rooms, yet how often do we neglect to 
make them either cheerful or healthful. Unless the 
builders of the house have provided some method of 
ventilation, the air may be changed by raising the lower 
sash of one window and lowering the upper sash of 
another. A better method, however, is to admit the 146 
THE ESSENTIALS OF HEALTH. 
air into the room through wire gauze, used as window 
screens. There are a number of ventilators for sale in 
the market which allow a free passage of air and yet 
effectually prevent draughts. 
If the lower window sash be raised about six inches 
and a board be placed under it, completely filling the 
space between it and the window casing, there wall be 
established some ventilation between the sashes where 
they meet but where they no longer fit tightly. This 
is a fairly good method for the winter, but hardly suffi- 
cient for the more quiet air of summer. 
The teacher generally gives personal attention to the 
ventilation of the schoolroom, and the proper authorities 
should insist that some method be devised in order that the 
change of air may be constant and abundant. This does 
not mean ventilation at noon and recess only ; it means 
that the change should be continuous and uninterrupted, 
for anything short of this fails to answer the purpose. 
Improper Ventilation. Ventilation is improper if it 
causes sudden changes in the temperature of the air. 
After the hearty plays of recess when the skin is moist 
with perspiration, the pupils should not sit down in a 
cool room. This is too often the cause of colds and 
coughs. The schoolroom should be of an even temper- 
ature all through the day; therefore there must be a 
constant and uninterrupted change in the air. Ventila- 
tion is improper if it produces a current of air ; if a 
draught of air be allowed to strike the back of the neck, 
or any sensitive part of the body, it is very likely to 
cause a cold These currents of air should be carefully 
avoided, especially when the body is resting from active 
exercise. VENTILATION. 
147 
Night Air. Some persons seriously object to opening 
the windows of their sleeping rooms at night, for fear of 
“the deadly night air.” Yet all the lower animals 
breathe it, from the delicate and tender young to the 
strong and aged. Soldiers and hunters breathe it as 
they sleep beneath their tents, and in the open air, while 
many invalids have been restored to health by living out 
of doors both day and night. Fear cold draughts, but 
do not fear the night air. Florence Nightingale said : — 
“ The choice is between pure air without and impure air 
within; most people prefer the latter, an unaccountable 
choice. An open window most nights in the year can hurt 
no one. In great cities the night air is the best and purest 
in the twenty-four hours. I could better understand, in 
towns, shutting the windows during the day than during 
the night.” 
Ventilate the Cellar. The cellars of houses and other 
buildings are often great reservoirs of foul air. The cel- 
lars of dwellings frequently have stored in them quantities 
of vegetable matter which give off injurious gases as they 
decompose. As the room is usually dark, the decaying 
organic matter is unseen, and hence it remains until the 
escaping gases penetrate the rooms above, and endanger 
the lives of their inhabitants. Cellars should be well 
ventilated, kept scrupulously clean, and so built, if pos- 
sible, that the sunlight can enter them. 
Sewer Gas. The escape of gas from defective plumb- 
ing of houses, and from improperly constructed drains 
and sewers, is the cause of much sickness. Gas may 
escape from a sewer which is near or under the house, 
and enter the rooms without being detected. The 
first intimation of its presence may be a severe case of 148 
THE ESSENTIALS OF HEALTH. 
diphtheria, or some low form of fever. No one should 
occupy a house, no matter how well it may be provided 
“ with all modern improvements,” until he is satisfied 
that the plumbing is in good condition, and that the 
sewers and drains are properly constructed. 
Deodorizers. One odor may cover another without 
destroying it. A free use of cologne may cover the 
odor of a poorly ventilated room, but it will neither 
remove the carbonic acid and organic matter, nor will 
it bring more oxygen. Coffee and sugar are often 
burned in a room to destroy some poisonous or disa- 
greeable odor. They do not destroy, however; they sim- 
ply cover one odor with another which is more powerful. 
Any substance that will replace or cover the odor of 
another, and yet not destroy it, is called a deodorizer. 
Disinfectants. There are substances which actually 
destroy odors; these are true disinfectants. Bad odors 
in the atmosphere often depend upon the presence of 
impurities dangerous to health and life; these must be 
removed, as far as possible, by free ventilation and by 
the use of destroying agents. Many chemicals possess 
the power of purifying the air from germs, and from the 
products of decaying animal and vegetable matter. Dis- 
infectants are used to purify sewers, cess pools, sinks, 
and to destroy the germs of scarlet fever, diphtheria, 
and small-pox. They are also largely used by Boards 
of Health and by physicians, to destroy disease germs. 
A disinfectant may be perfectly .odorless itself, and 
yet have the power of destroying the most offensive 
odors. The chlorides and sulphates of the metallic salts 
are powerful disinfectants. Preparations of the chlorides 
are on the market which are reliable and convenient. VENTILATION. 
149 
The sulphate of iron (copperas), dissolved in water in 
the proportion of four ounces to the gallon, is a useful 
disinfectant for cleansing gutters, drains, sewers, etc. 
Absorbents. Absorbents are used to take up the gases 
from decomposing materials. Lime and charcoal are 
the most frequently used for this purpose. White- 
washing a room renders the air sweeter and purer be- 
cause it absorbs certain gases in the atmosphere. 
Contagion. Some of the most poisonous substances 
are entirely free from odor. This is the case with the 
germs which are believed to cause a number of diseases. 
Scientists are not agreed as to the germ theory of 
disease, but it seems altogether probable that a number 
of diseases, such as diphtheria, scarlet fever, measles, 
and small-pox are caused by minute germs. In some 
way the germs gain an entrance into the body where 
they develop and cause disease. 
If a well person approaches one thus ill and comes in 
contact with these germs, and if the body of the well 
person be in just such a condition that these germs can 
there thrive and develop, then the exposed party will, 
in due time, be ill with the same disease. These germs 
may lie dormant for years until their surroundings are 
suitable for their development. A grain of wheat may 
be kept for years and show no signs of life; but when 
at last it is surrounded with warmth and moisture it 
begins to revive and to give evidences of life. Soon a 
sprout appears, when, if food and sunlight be added, it 
will bear fruit. 
Thus disease germs may remain in a room for a long 
time, clinging to the paper, the carpet, or the walls. 
Months, or even years afterwards, some inhabitant of 150 
THE ESSENTIALS OF HEALTH. 
the room may fall a victim to scarlet fever or small- 
pox. Then it is remembered that not since the illness 
of the last patient has the room been occupied, and never 
has it been thoroughly disinfected. Germs may not only 
lie dormant in this way, but they may be carried long- 
distances in the clothing, or in the hair. 
Prom the above outline, only too brief for such an 
important subject, some valuable conclusions may be 
drawn. Persons suffering from such contagious diseases 
as scarlet fever or diphtheria should be kept in a well 
ventilated room, which none but the physician and nurse 
should enter; the nurse should leave the room only for 
exercise, and then she should have a second room in 
which she could change her clothing, and make free use 
of the best disinfectants. These ideas are now thor- 
oughly understood by all competent physicians, who can 
be relied upon to see them carried out in detail. 
QUESTIONS. 
1. Give the amount of air inhaled with each inspiration. 
2. What is said about the necessity of oxygen ? 
3. What do you learn about carbonic acid ? 
4. Pure air should contain what ? And be free from what ? 
5. Give some of the bad effects from a deficiency of air. 
6. The supply of fresh air required for a room depends upon 
what conditions or circumstances? 
7. Give some of the methods mentioned for ventilation. 
8. When is ventilation improper ? 
9. What is a deodorizer ? 
10. What is a disinfectant ? Name one. 
11. Name some absorbents. THE KIDNEYS. 
151 
CHAPTER XIV. 
THE KIDNEYS. 
General Description. The kidneys are two in number, 
one on either side of the spinal column. Each kidney 
is about four inches in 
length, two inches in 
breadth, and about an 
inch in thickness, and 
from four and one half to 
six ounces in weight. The 
upper border of the kid- 
ney is about on a level 
with the eleventh rib. 
A kidney resembles a 
bean in shape. It is com- 
pletely covered with a 
thin membrane, called the 
capsule. The convex bor- 
der of either kidney is 
placed toward the side of 
the body, while the con- 
cave border is next the 
spinal column. Each kid- 
ney is supplied with blood by an artery which arises 
from the aorta. This vessel enters the kidney as shown 
Fig. 45. A kidney : A, an artery ; 
y, a vein ; d, the duct that carries 
away the materials filtered from the 
blood. 152 
TIIE ESSENTIALS OF HEALTH. 
at A. Fig. 45. After the arterial blood lias circulated 
through the kidney it is returned through a vein at V. 
This vein empties into the large vein which lies by the 
side of the aorta. 
Minute Structure. 
On making a section 
through the long di- 
ameter of a kidney, 
a s represented i n 
Fig. 46, it appears 
to consist of two 
different substances. 
The outer part, near 
the convex border, 
looks red and gran- 
ular. Farther in, 
are seen a number 
of little eminences, 
illustrated at 5, Fig. 
46. Fine lines ex- 
tend fan-shaped, 
toward the convex 
border. They re- 
present a collection 
of canals. 
The most interest- 
ing portion of the 
kidney is found in 
that part near the 
convex border, to the left of Fig. 46. Here active changes 
are constantly taking place. In this portion there are 
seen, with the microscope, vast numbers of small, round, 
Fig. 46. A section through a kidney : 
(1, 2, 3, 4), collections of tubes, or canals; 
(5), papillae on which the tubes open; (6), 
below the end of the dotted line is a blood 
vessel; others are seen above this ; (7), the 
dilated beginning of the duct, (8), which 
carries the secretion from the kidney. THE KIDNEYS. 
153 
red bodies, which are but the beginnings of long, narrow 
tubes. Two of these red bodies are illustrated in Fig. 
47. Each body consists of coils of capillary blood ves- 
sels, surrounded by a mem- 
brane. While the blood is 
circulating through these 
bodies, certain substances, 
principally wrater, are 
taken from the blood. 
These substances are car- 
ried away through the mi- 
nute canals until they empty 
into a large duct, shown at 
7 and 8, Fig. 46. This duct 
carries the secretion directly 
to a reservoir, designed 
especially for its reception. 
Thus we find that the 
kidneys are purely excretory 
organs, taking from the blood materials which would 
rapidly prove poisonous if allowed to remain in the 
body. 
Urea. The most important ingredient taken from 
the blood by the kidneys is called urea. It represents 
the worn-out, or used up, nitrogenous tissues of the 
body. A greater part of the nitrogen which enters the 
body with the foods is removed from it by the kidneys 
in the form of urea. If, for any reason, the kidneys 
fail to take the urea from the blood, the most serious 
results follow. Symptoms of blood poisoning soon ap- 
pear, and convulsions and even death speedily follow, 
unless the difficulty be promptly relieved. 
Fig. 47. One of the tubus of the 
kidney, magnified. 154 
THE ESSENTIALS OF HEALTH. 
If some of the tubes be affected, as in Bright’s dis- 
ease, then the kidneys do not completely remove the 
waste products from the blood, and prolonged sickness 
results. At last, the accumulation of urea in the system 
is sufficient to produce poisoning and death. 
Danger from Colds. Disease of the kidneys is often 
caused by exposure to cold, especially if the body be 
moist with perspiration at the time. If the function of 
the skin be suddenly checked by the action of cold, the 
blood leaves the surface and goes to internal organs, as 
the kidneys, causing congestion; the excretory work the 
skin was performing is thus suddenly thrown on the 
kidneys, making them do double duty. As a result 
they become inflamed and unable to properly perform 
their work. 
ALCOHOL, AND THE KIDNEYS. 
Alcohol is recognized as one of the most frequent 
causes of kidney disease, and especially of that form 
known as Bright’s disease. When much alcohol is 
used, a certain proportion of it passes out of the body 
unchanged, through the kidneys. The alcohol comes in 
contact with the delicate cells lining the tubes, and so 
alters them that they are unfitted to do their work. 
If the use of the alcohol be continued the cells grad- 
ually diminish in size, the round bodies become smaller, 
and the tubes and canals likewise are reduced. The 
connective tissue, which is used only to hold the tubes 
and canals together, grows thicker and thicker, until the 
whole organ becomes largely composed of it. T11E KIDNEYS. 
155 
At last many of the tubes become so useless that the 
urea is not taken from the blood, and death occurs. To 
produce these changes in the structure of the kidney it 
is not necessary that the drink be strong with alcohol. 
Many such cases are directly caused by the use of ale 
and beer. 
It is absolutely necessary that all poisonous materials 
be removed from the body as nature intended. We may 
deprive ourselves of food and keep nourishment from en- 
tering the body for days at a time. We may, in this 
way, check the action of those organs directly concerned 
in the secretion of the digestive juices, as the stomach 
and the pancreas. But we cannot check, even for the 
shortest time, the action of those organs employed in 
the removal of the worn-out and poisonous materials 
of the body, without seriously endangering the health 
and even the life. 
In view of these facts, it does not seem possible that 
any one who is familiar with them would try the experi- 
ment of taking alcoholic beverages into the body ; espe- 
cially so when science so clearly points to their direct 
effect on such important organs as the kidneys. It is 
an experiment that has cost many thousands of lives. 
1. Give a general description of the kidneys. 
2. What is the most important ingredient taken from the blood 
by the kidneys ? 
3. What does the urea represent ? 
4. Explain how exposure to cold affects the kidneys. 
5. Give some of the effects of alcohol on the kidneys. 
QUESTIONS. 156 
TI1E ESSENTIALS OF HEALTH. 
CHAPTER XV. 
THE BONES. 
General Description. There are two hundred and four 
distinct bones in the body. This does not include the 
teeth, the patella or knee-pan, and a few other bony 
structures occasionally present. The bones vary greatly 
in form; some are long and stout, as the femur; others 
are short and small, as the bones of the hand and foot. 
Some are flat, as many of the bones of the skull, while 
others are so irregular that it would be very difficult to 
describe them. On closely examining one of the larger 
bones, eminences and depressions are seen. The emi- 
nences afford places for the attachment of muscles and 
tendons, while the depressions afford passages for blood 
vessels, nerves, and tendons. 
Fig. 48. A bone with the periosteum partly peeled off. 
The Periosteum. A thin membrane called the perios- 
teum. surrounds each bone. It is composed of two lay- 
ers, an outer layer of firm tissue, which is simply for THE BONES. 
157 
support and protection, and an inner layer of cells. 
This inner layer is essential to the life of the bone, and 
its cells are even capable of 
forming new bone. In cases 
where it is necessary to re- 
move a portion of a bone, 
the surgeon avails himself of 
this fact. He simply peels 
back the membrane, removes 
the injured bone, and thus 
leaves the periosteum to 
make new bone. 
The periosteum is well 
supplied with blood vessels, 
some of which pass directly 
into the bone through mi- 
nute openings on the surface. 
Many of these openings can 
be seen on any bone from 
which the periosteum has 
been removed. 
Compact and Cancellous Tis- 
sue. If one of the long bones 
of any animal be sawed 
lengthwise, it will be found 
to be hollow, except at the 
ends. The hard, thick wall, 
midway between the ends of 
the bone, is called the com- 
pact tissue; while the 
spongy, honey-combed bone, 
occupying the center of the ends of the bone is called 
Fig. 49. Longitudinal section 
of the femur. The spongy, or 
cancellous hone shows at the ends ; 
while the compact, hollow bone 
forms the shaft. 158 
THE ESSENTIALS OF HEALTH. 
the cancellous tissue. The smaller bones and the flat 
bones are not hollow ; they have an outer layer of com- 
pact bone, within which is the spongy bone, or cancel- 
lated tissue. 
Fig. 50. Transverse section of the femur. The section to the left is from 
the shaft; to the right is from the head or upper portion of the femur. 
The Marrow. The large central cavity of the long 
bones, and all the spaces in the spongy bone, are filled 
with a yellowish or reddish substance, called marrow. 
It consists principally of fat cells and marrow cells. 
These marrow cells doubtless give rise to some of the 
red corpuscles of the blood. There are other sources of 
origin for these corpuscles, but it is well established that 
some of them originate in this way. 
Microscopic Structure. If a longitudinal piece of bone 
be ground very thin, and then examined with a micro- 
scope, a number of canals will be seen parallel to fhe 
long axis of the bone. These canals unite with eacli 
other, as shown in Fig. 51, by short branches extending 
across nearly at right angles. A cross section of bone 
shows that these canals are circular or oval in shape, as THE BONES. 
159 
illustrated in Fig. 52. These are the Haversian canals, 
so called after their discoverer, Cloptin Havers. In the 
living bone all these canals are filled with blood vessels, 
while the frequent communication of the canals permits 
the blood to How to all parts of the bone. But the most 
Fig. 51. Longitudinal section of bone, showing the Haversian canals, 
magnified. 
interesting fact connected with the structure of bone is 
that living cells are always present in them. 
The Bone Cells. Between the Haversian canals there 
are oblong spaces, called lacunae, signifying a hole or a 
lake. Extending from the lacunae in every direction, 
are minute canals, called canaliculi. In these irregular- 
shaped spaces are the bone cells. In Fig. 53 is a longi- 
tudinal section of bone showing these holes, with their 
many-branched canals extending from them. Fig. 52 is 
not so highly magnified, but it represents the vast number 
of these lacunae, with their canals leading from them. 
The lacunae are very small, yet the canaliculi are 
much smaller, being not over °f an inch in 
diameter. Yet in all these there is living matter. 160 
THE ESSENTIALS OF HEALTH. 
the bone cells. These cells are nucleated, and are of 
the same shape as are the spaces in which they rest. 
Therefore the idea that bone is dead tissue, not subject 
to change, must be abandoned. Bone is a living tissue, 
filled with blood vessels, nerves, and cells, which are as 
much endowed with life as are the cells of other parts 
of the body. A framework of fibers extends throughout 
the whole bone, holding all the parts in place. 
Fig. 52. Transverse section of bone, not as highly magnified as 
Fig. 53. Four Haversian canals (a) show, surrounded by lacunae and 
canaliculi. 
Animal and Mineral Matter. The parts just described 
— the blood vessels, bone cells, marrow, nerves, and the 
framework of fibers — constitute the animal matter of 
bone. But the body must have a strong support, some 
kind of a framework to which muscles can be attached, 
and in which the most delicate organs can be protected. 
We find, therefore, that some mineral substance is added THE BONES. 
161 
to the soft and yielding animal matter ; this makes the 
whole tissue hard and unyielding. 
By remembering that fire will destroy animal matter 
and that acids will dissolve mineral matter, some inter- 
esting results may be obtained. For instance, if a fresh 
Fig. 53. Longitudinal section of bone, highly magnified. Between 
the two Haversian canals are a number of lacunae and canalieuli. 
bone be placed in the fire, and subjected to heat for a 
considerable time, all the animal matter can be burned 
out. The shape of the bone will not be changed ; it will 
only become lighter and whiter. After such treatment 
it can be easily broken and pounded into a fine powder. 
The mineral matter consists largely of lime. This is 
easily removed by soaking the bone in a weak acid for 
a few hours. The shape of the bone will not be changed ; 
it will only lose its hardness, and become easily bent in 
any direction. All the blood vessels and the bone cells 
still remain in the bone. 162 
THE ESSENTIALS OF HEALTH. 
From these experiments we easily draw the conclu- 
sion that, if the bones do not contain the proper amount 
of mineral matter, they will bend, and will be unable to 
keep their shape, and properly support the tissues around 
them. If there is a deficiency in the amount of animal 
matter, the bones will be too brittle, and liable to break 
if any extra strain be brought upon them. 
Nature very wisely provides that in early life there 
should be an excess of the animal matter in bone. If 
this were not so the tumbles and falls which are the 
common lot of all children at play, would result in many 
serious injuries. But the bones of youth have such a 
spring to them that children are not likely to suffer often 
from their fracture. In old age the opposite condition 
exists, and there is an excess of mineral matter. The 
bones are very brittle, and are much more easily broken; 
a slight fall often being sufficient to fracture a large bone. 
The Reproduction of Bone. It has already been stated 
that bone is a living tissue. Because of this, it is capa- 
ble of being reproduced if only some of the original cells 
be left undisturbed. If the end of a young bone be re- 
moved it may again be reproduced so that a fairly good 
joint will be formed. Pieces of bone that have been 
broken, or sawed off will again unite with the original 
bone. 
We have already mentioned that if a portion of bone 
be removed and the periosteum left, new bone will 
soon take its place. The periosteum, even when trans- 
planted to another part of the body, will give rise to 
new bone. If a large bone be fractured, the periosteum 
soon deposits a substance on the broken ends. This is 
at first soft, and of jelly-like consistence ; later it be- THE BONES. 
163 
conies more solid and resembles cartilage; and still 
later thin layers of bone appear, reuniting the broken 
ends. As hard and firm as bone appears, physiology 
teaches that it is subject to the same laws of repair and 
waste, growth and decay, as are the other tissues of the 
body. 
A Good Form. To have a fine, erect figure is certainly 
desirable. But this cannot be secured if certain laws 
of nature be persistently broken. The body must not 
be distorted by improper dress, or by wrong methods of 
walking or sitting. The figure is easily made crooked 
by repeatedly yielding to a feeling of languor, or by sit- 
ting in a cramped and unnatural position. In standing 
it is better to rest the weight on both feet. The habit 
of resting the weight on one and the same foot is sure 
to make the hip bones grow out of shape ; it will also 
bend the spine, and make it incline toward one side. 
In walking, the whole body should be erect, with the 
shoulders well thrown back. 
1. Give a general description of the bones. 
2. What is the periosteum ? 
3. Where is compact bone found? Where cancellous? 
4. Where is the marrow found? Of what is it composed? 
5. Describe the bone cells. 
6. What constitutes the animal matter of bone ? 
7. How does fire affect bone ? 
8. How can the mineral matter be removed ? 
9. What conclusion can be drawn from these experiments ? 
10. During what period of life do the bones contain an excess of 
animal matter? When an excess of mineral matter? 
11. How is bone reproduced ? 
QUESTIONS. 164 
THE ESSENTIALS OF HEALTH. 
CHAPTER XVI. 
THE SKELETON. 
Object of the Skeleton. All the higher animals are 
provided with a skeleton. This is used either as a sup- 
port, or framework, for the organs and tissues of the 
body, or as a protection from injury. In some of the 
lower animals the skeleton is entirely on the outside. 
The oyster is completely inclosed in its hard shell, and 
is thus well protected against the attacks of enemies. 
The lobster has an exterior skeleton also, but the parts 
are so arranged that there is considerable freedom of 
motion. The turtle not only has an interior skeleton, 
but also a large plate, or exterior skeleton of hard ma- 
terial. This animal can withdraw his head beneath the 
outer skeleton, and thus the whole body is protected 
from violence. 
The animals which have exterior skeletons do not 
have such freedom of motion as is required by the 
higher animals. Therefore, in man, beasts, birds, fishes, 
and some other animals, the skeleton is entirely within 
the body. It gives to the body a solid framework, to 
which can be attached ligaments for holding the joints 
together, and muscles for moving the various parts. 
It also makes a more or less complete covering, or pro- 
tection, to many important organs. As a protection, THE SKELETON. 
165 
the bones of the skull furnish a perfect covering to the 
delicate texture of the brain ; they nearly surround the 
eye; while the most delicate parts of the ear are deeply 
imbedded in bony tissue. The ribs, spinal column,.and 
sternum make a nearly complete covering for the heart 
and lungs. 
Bones of the Skull. The skull is composed of twenty- 
two bones, which are usually divided into the bones of 
the cranium, and the bones of the face. The bones of 
the cranium are eight in number, and they are so ar- 
ranged that they form a solid and strong covering for 
the brain. At the base of the brain is a large opening 
through which passes the spinal cord and large blood 
vessels. The bones of the face are fourteen in number ; 
they protect the organs of the special senses of sight, 
smell, and taste, and they also provide for the recep- 
tion of the teeth. 
The skull rests upon the first vertebra and upon a 
tooth-like projection, or pivot, of the second. It nods, or 
moves forward and backward, upon the first vertebra, 
which remains stationary. It moves from side to side 
by the motion of the first vertebra upon the second. 
During this motion the skull and the first vertebra 
move together, the vertebra swinging around the pivot, 
which extends upward from the vertebra below it. A 
glance at Figs. 53, 54, and 55 will aid in making this 
clear. 
The Spinal Column. The spinal column consists of 
twenty-four small bones, — resembling those illustrated 
at Figs. 56 and 57, — and two irregular bones, at the 
lower end of the column. The two irregular bones, 
at an early period of life, are composed of nine 166 
THE ESSENTIALS OF HEALTH 
separate pieces, each representing 
a vertebra. Later, five of these 
unite to form one bone, and four to 
form another. These two compound 
bones form the back of the pelvic 
cavity. 
A reference to Fig. 54 shows that 
the spinal column is not straight, but forms 
a series of curves. In the neck, and in 
the abdomen, the convexity of the curves is 
forward, while in the chest, and in the pel- 
vis, it is backward. These curves give 
additional elasticity to the column, and 
with the aid of the elastic cartilages give 
great protection to the brain from sudden 
jars. 
Each bone in the spinal column is 
called a vertebra, from a Latin word 
signifying to turn, as a joint. Thus a 
translation or definition of the word 
would be, “ a joint of the spinal col- 
umn.” Each vertebra has within it 
a large opening, through which passes 
the spinal cord. The vertebrae are 
held together by ligaments, and are 
so placed, one directly over the other, 
that the central openings form a con- 
tinuous canal extending the entire 
length of the spinal column. This is 
called the spinal canal; it furnishes a 
Fig. 54. The spinal column. The right side 
of the figure is toward the hack of the body. THE SKELETON. 
167 
firm protection to the spinal cord. Between the ver- 
tebrae are discs, or cushions, of elastic cartilage. This 
cartilage resembles rubber 
in its elasticity. Its great 
use can be appreciated 
when it is stated that 
the combined thickness of 
all these cushions is over 
six inches. They greatly 
diminish the shock and jar 
that comes to the body from 
jumping and running. 
Nearly all the vertebrae 
resemble those shown in 
Figs. 56 and 57. Fig. 56 
illustrates a vertebra of 
the neck, as viewed from 
above. The long process, 
C, is the one that is so 
easily felt at the back of the neck. The darkly shaded 
oval portion at the top of the figure, immediately in 
front of the opening for the spinal cord, is the place of 
attachment of the elastic cartilage. Fig. 57 represents 
a vertebra lower down the spinal column, and viewed 
from the side. A represents the front of the vertebra, 
and the place where the cartilage is attached. The long 
process, B, extends backward and downward, forming 
a part of the ridge which may be felt extending down 
the center of the back. 
Fig. 55. Two vertebra, with the 
elastic cushion of cartilage between 
;hem. 
The “ atlas ” is so named because it supports the 
globe of the head. It stands at the top of the spinal 
column, and differs in shape from the other vertebrae. 168 
TIIE ESSENTIALS OF HEALTH. 
It has no cushion of cartilage to separate it from the 
bones above or below it, neither has it any long process. 
There are two places on 
the atlas, however, which 
are of interest; they are 
illustrated at 3, Fig. 58. 
On these surfaces the 
base of the skull rests 
and moves. It has a 
large opening in its cen- 
ter, which is divided into 
two parts by a strong 
ligament, ill ustrated in 
Fig. 58 by a dotted line. 
Through the back and 
larger o p e n i n g, 2, the 
spinal cord passes; while 
through the smaller 
opening, 1, passes a bony pivot, projecting up from the 
bone directly beneath. 
The “ axis ” is so 
named because it 
forms the pivot upon 
which the head turns 
from side to side. Its 
most peculiar feature 
is the strong bony 
projection, resembling 
a tooth, which rises 
perpendicularly from 
its upper and front 
part. When the atlas and the axis are in position 
Fig. 56. The upper surface of one 
of the vertebrae of the neck: a is an 
opening in each side for a blood vessel; 
B is the point on which the bone 
above it rests ; c is the long process 
that forms a part of the ridge which 
extends from the back of the spinal 
column. 
Fig. 57. One of the vertebrae viewed 
from the side : A, represents the body of 
the vertebra ; b, the process. THE SKELETON. 
169 
they correspond with Fig. 60. A study of these last 
three illustrations will make it clear how the head 
turns from side to side with the atlas, while the axis 
is stationary,—both 
the head and the atlas 
rotating on the pivot 
of the axis. They also 
show how the head can 
bend forward and back- 
ward, while the atlas re- 
mains fixed and immov- 
able upon the axis. It 
ns one of the most curious 
and wonderful mechan- 
isms of the body. 
The Ribs. There are 
twelve ribs on each side 
of the body. The ribs are so curved that each makes 
an elastic arch of bone. Behind, the ribs are attached 
to the spinal column. In 
front, the first seven are at- 
tached to the sternum, by 
means of cartilages. The 
next three are fastened to 
each other by cartilages; 
while the last two have no 
attachment in front, hence 
they are called the floating 
ribs. 
The Thoracic Cavity. The 
thoracic cavity is inclosed by 
the spinal column behind, the sternum in front, the ribs 
Fig. 58. The atlas, or the first 
vertebra, viewed from above: (1) the 
process of the axis ; (2) the opening 
for the spinal cord; (3) the places on 
which the skull rests. The dotted 
line represents a ligament which holds 
the process, (1), in place. 
Fig. 59. The axis, or the sec- 
ond vertebra, viewed from the 
side : (1) the process on which 
the atlas turns seen also at 1, 
(Figs. 58, and 60) ; (2) the place 
on which the atlas rests. 170 
THE ESSENTIALS OF HEALTH. 
on the sides, and the diaphragm below. The spaces be- 
tween the ribs are filled in with muscular tissue, so that 
surrounding the thoracic cavity there is a complete wall, 
formed partly of bone and partly of muscle. All that part 
Fig. 60. The atlas and axis in position, front view : (1) the toothy 
like process of the axis, showing above the atlas; (2) the axis; (3) the 
atlas. 
of Fig. 43 which is above the diaphragm, 6, represents 
the thorax, or chest, with its contents in place. In this 
cavity are the lungs, heart, and large blood vessels. 
The Upper Extremities. There are five large bones 
and several small ones that belong to the upper ex- 
tremity. The clavicle, or collar bone, extends from the 
front of the shoulder to the top of the sternum ; it keeps 
the shoulder joint outward and backward. The scapula, 
or shoulder blade, forms the back part of the shoulder, 
and is between the shoulder joint and the spine ; at its 
upper and outer part is a cavity, or socket, for the re- 
ception of the head of the humerus. The humerus, or 
arm bone, extends from the shoulder to the elbow. Its 
head is round, forming a ball for the ball-and-socket 
joint at the shoulder; the lower end is flattened and 
grooved, to make the hinge joint of the elbow. The 
radius and ulna are the two bones of the forearm. THE SKELETON. 
171 
The ulna forms the hinge joint at the elbow with the 
humerus, while the radius forms the upper part of the 
wrist joint. The radius and ulna are placed side by 
side, and are so arranged that the radius can move 
Flu. 61. Front view of the sternum and parts attached to it; (a, b, c) 
the three portions of the sternum ; (1, 2, 3, 4, 5, 6, 7) the cartilages 
which unite the first seven ribs directly to the sternum ; (8, 9, 10) the 
cartilages which unite the eighth, ninth, and tenth ribs indirectly to the 
sternum. To the right of the Fig. only the cartilages are shown ; to 
the left, the ends of the ribs are shown also. 
partly around the ulna, giving the hand the power 
of rotation, or turning. The radius is on the side of 
the arm corresponding with the thumb. The remain- 
ing bones of the upper extremity form the hand, and 
by their arrangement allow a great variety of move- 
ments. 172 
THE ESSENTIALS OF HEALTH. 
The Pelvis. The pelvis is inclosed, on the back, by 
the two lower bones of the spinal column; on the 
sides, by the large hip bones; and 
in front, by the pubic bones. The 
curved shape of the upper edge 
of the hip bones gives a strong 
support for the abdominal 
organs. The sides furnish a 
means of attachment for the 
lower extremities, while the back 
gives attachment to the spinal 
column. 
The Lower Extremities. The 
bones of the lower extremity are 
much like those of the upper. 
The femur, or thigh bone, is the 
longest, largest, and strongest 
bone in the body. Its head is 
ball shaped to form the ball-and- 
socket joint with the bones of the 
pelvis. Near the head is a rough- 
ened mass of bone, to which mus- 
cles are attached. The lower end 
of the bone is flattened, to form, 
with the tibia, the hinge joint of 
the knee. The tibia and fibula 
are the two bones which form the 
leg. They are placed side by side, 
but are not movable as are the 
bones of the forearm. The front 
of the tibia forms the sharp ridge 
felt in the front of the leg, while the fibula forms the out- 
Fig. 62. The femur. THE SKELETON. 
173 
side of the leg. The patella, or knee pan, protects the 
knee in front. 
Bones of the Foot. The bones of the foot are so united 
that they form an arch, of which only the front and the 
back touch the ground. 
This arch is useful in 
protecting the body 
from severe shocks, as 
in the act of running or 
jumping; for it is evi- 
dent that when the 
weight of the body is 
thrown upon the arch, 
its center is pressed downward, thus acting as a 
spring. 
The Joints. Whenever bones form a 
joint they are covered with a layer of 
highly polished cartilage. This gives 
some slight elasticity, and also reduces 
the friction. Covering the cartilage is a 
very thin membrane which is constantly 
secreting, or pouring out, a watery fluid, 
called the synovial fluid, or joint water. 
It serves the same purpose as does oil 
to the wheels and joints of machinery. 
The Ligaments. The bones are held to- 
gether at the joints by bands of tissue, 
called ligaments. These are very dense 
and strong, ,and capable of withstanding 
Fig. 63. Side view of the bones of 
the foot, naturally arranged in the form 
of an arch. 
Fig. 64. A longitudinal section through a joint, 
showing a layer of cartilage over the end of each bone : 
(1) the ends of the hones ; (2) the layers of cartilage. 174 
THE ESSENTIALS OF HEALTH. 
great strain without injury. Fig. 65 shows how firmly 
and completely the shoulder joint is covered with these 
ligaments. Fig. 66 illustrates how the head of the fe- 
mur is buried in the socket prepared for it; while Fig. 
67 illustrates the hip 
joint after the outer 
ligaments have been 
removed, and the bone 
pulled partly out of its 
socket. A strong liga- 
ment still remains, 
holding the head of the 
femur to the center of 
the socket. 
Sometimes the liga- 
ments are unduly 
stretched, or slightly 
torn, as when the wrist 
or ankle is sprained. 
Such an injury usually 
causes great pain, and 
recovery is slow. The 
ligaments may be so 
broken or torn that the 
bones slip out of their 
proper places. The bone 
is then said to be “ out 
of joint,” or dislocated. In a few healthy persons the 
ligaments are very loose, so that, by the action of the 
muscles alone, some of the joints can be dislocated at 
will. Such persons are said to have loose joints. 
Fig. 65. Front view of the bones of 
the shoulder : (1) the clavicle ; (2) a 
process which extends from the back of 
the scapula, and which can be felt as a 
prominence on the back of the shoulder ; 
(3) the scapula ; (4) the humerus. The 
joint is enclosed by ligaments. 
Varieties of Joints. Joints may bo either movable, im- THE SKELETON. 
175 
perfect, or immov- 
able. The movable 
joints vary exceed- 
ingly in the degree of 
their mobility. The 
opposing bony sur- 
faces move upon one 
another, and the ex- 
tent of the motion 
is only limited by 
the structure of that 
particular joint. The imperfect joints 
are such as are found in the spinal 
Fig. 66. A section through the hip joint, illus- 
trating the head of the femur resting in a socket, and 
thus forming a ball-and-socket joint. 
Fig. 67. The hip joint, opened. All the 
ligaments have been removed except the one 
which holds the head of the femur to the 
bottom of the socket. 176 
THE ESSENTIALS OF HEALTH. 
column. There is some slight motion between the ver- 
tebrae, due to the elasticity of the thick plates of car- 
tilage. It is the same motion that can be made after 
cementing a thick 
plate of rubber be- 
tween two blocks of 
wood. The elasticity 
of the rubber would 
allow a certain free- 
dom of motion and 
yet the parts would 
not move upon one 
another. Examples of 
the immovable joints 
are seen in the union 
of the bones of the 
skull. The edges of 
the bones are so fitted 
into each other that 
they form an unyield- 
ing joint, or suture. 
The Ball-and-Socket Joint. In the ball-and-socket joint, 
the head of one bone, which is more or less round like 
a ball, plays in the socket, or depression, of another 
bone. The bone with the round head can move in any 
direction, only the extent of its motion will depend upon 
the shape of the socket. If the socket be deep and 
small, as in the hip, the motion will be limited, but if 
the socket be shallow and broad, as in the shoulder, 
then the motion will be free in every direction. 
Hinge Joints. The movements of the hinge joints are 
compared to those of a door. The elbow is the best 
Fig. 68. The upper surface of the 
skull, showing the sutures, or immova- 
ble joints. TIIE SKELETON. 
177 
example of a hinge joint. The movement is limited, for 
while the arm can be bent forward and then straight- 
Fig. 69. The scapula and humerus in proper position to form the ball- 
and-socket joint of the shoulder. 
ened, yet it cannot be bent backward. The knee is 
another example of this joint. 
Fig. 70. A section through the elbow joint: h, the humerus ; u, the 
ulna ; p, the process, which prevents the arm from moving back of a cer- 
tain line. 
Pivot Joints. The rotary motions of the head, by 
which the skull and the atlas turn upon the pivot of the 
axis, furnish an illustration of a pivot joint. 178 
THE ESSENTIALS OF HEALTH. 
SUGGESTIONS TO TEACHEKS. 
1. The Marrow of Bone. Cut a transverse section of a 
fresh bone ; the bone in a round steak answers well. The 
oily matter, within the bone, is the marrow. 
2. The Periosteum. Cut down on any fresh bone and 
peel off the membrane surrounding it. This is the 
periosteum. 
3. The Mineral Matter. Burn a bone in the stove. The 
heat soon destroys the animal matter, leaving only the 
mineral. A burned bone is easily broken and pulverized 
with a hammer. 
4. The Animal Matter. Place one of the long bones of 
a small animal, as the rib of a chicken, in a weak acid 
solution, — nitric acid, one part; water, four or five parts. 
In a few days pour off the acid, and place in water to 
wash out any remaining acid. If the bone has been in the 
acid long enough it can be bent and even tied in a knot. 
The acid has removed the mineral matter; the animal 
substance remains. 
5. Spongy Bone. Saw any old dry bone lengthwise; 
especially the ends of any of the long bones. Notice 
the fine, honey-combed, spongy bone in the ends of the 
bones; while the body of the bone, between the ends, is 
hollow. 
6. Entrance of Blood Vessels. Minute openings can be 
seen on the surface of any dried bone, as picked up in the 
field. Through these openings the blood vessels entered 
the bone, dividing again and again until small enough te 
enter the narrowest Haversian canal. SUGGESTIONS TO TEACHERS. 
179 
7. Ligaments. Any joint can be procured at the market 
and the outer layer of tissue removed. Still the joint is 
out of sight, covered with the hard, tough ligaments. 
8. Synovial Fluid. If the joint be from a recently killed 
animal, when the knife cuts through the ligaments, a few 
drops of a watery substance escape. This is the lubricating 
synovial fluid. 
9. Joints. With a saw divide the joint longitudinally, 
as represented in Figs. 66 and 70. Notice the working of 
the joint, the smooth articulating surfaces, and the great 
strength of the ligaments. 
10. Cartilage at the Joints. In the last preparation, 
notice the cartilage covering the ends of the bones. Sepa- 
rate the joint completely and cut the cartilage with a knife. 
Notice the depth of the layer, and its shining, highly pol- 
ished character. 
11. Cartilage between the Vertebrae. Procure two ad- 
joining vertebrae and cut them likewise. Examine the 
intervening cartilage. It appears elastic when pressed. 
It does not cut easily with a knife. This is not the same 
kind of cartilage as found at the joints. 
12. Connective Tissue. When examining any piece of 
fresh meat, especially the outer part, soon after the skin is 
removed, a whitish tissue is seen. This can be pulled and 
stretched easily, with a pair of forceps. It is the tissue 
which holds, or connects the skin to the muscles and tissues 
beneath it. Connective tissue holds many of the tissues 
together and unites one kind of tissue with another. It is 
seen between the muscles, surrounding blood vessels, and 
forming the tendons to muscles. It is very generally dis- 
tributed throughout the body. 180 
THE ESSENTIALS OF HEALTH. 
CHAPTER XVII. 
THE MUSCLES. 
General Description. The great bulk of the body, ex- 
ternal to the skeleton, is composed of muscles. The 
muscles give the general outline to the body and make 
nearly one half its total weight. Nearly all the muscles 
are arranged in pairs, so that the two sides of the body 
are almost alike. Some of the muscles are very small, 
as the minute muscles of the middle ear, while others 
reach from the hip to the knee. They are of a deep red 
color in the majority of animals, forming the lean meat 
or flesh. In many of the fishes, and in some of the birds 
the muscles arc white, or of a light yellow color. 
Two Kinds of Muscle. The muscles are, in respect to 
their function, divided into two classes; the voluntary, 
and the involuntary. The voluntary muscles are so- 
called because their movements are under the control of 
the will. Such muscles can be used whenever we wish 
or will to use them, as the muscles of the face or the 
arm. Others cannot be controlled in this way; they do 
their work independent of any action of the will, hence 
they are called involuntary. The muscles of the stom- 
ach and the heart are of this variety. The heart beats, 
the stomach contracts, and we are powerless to stop 
their action. As a rule, all those movements in the THE MUSCLES. 
181 
body most essential to life are not under the control of 
the will. Yet many of the involuntary muscles can be 
controlled, although for a short time only. An illus- 
tration of this is found in 
ordinary breathing. We 
breathe a certain number of 
times a minute and are entirely 
unconscious of it; still by an 
effort of the will, we can 
breathe faster, slower, or 
deeper. Even the voluntary 
muscles can be made to con- 
tract by a sharp blow, or by 
some fright. While voluntary 
muscles, therefore, are con- 
trolled by the will, they are 
not invariably so controlled. 
Nearly all the voluntary mus- 
cles are attached to bone at 
each end ; while the involun- 
tary are not attached to the 
skeleton, but are found in the 
walls of hollow organs, as the 
stomach and intestines, and in the walls of the arteries. 
Fie. 71. Voluntary muscle, 
with its blood vessels : (1) the 
muscle fibers ; (2) the blood ves- 
sels, magnified. 
The Uses of Muscle. The muscles are primarily the 
organs of motion. They act as a protection to the 
blood vessels and nerves; they inclose the large tho- 
racic and abdominal cavities ; they serve as cushions 
to diminish the force of falls and blows; they fill up 
irregularities, and thus add to the symmetry of the 
whole bodv. 
Structure of Voluntary Muscle. If a piece of lean meat, 182 
THE ESSENTIALS OF HEALTH. 
which is voluntary muscle, be boiled, it will appear as if 
ready to fall apart into little bundles of tissue. These 
bundles may be easily divided into 
still smaller ones, by separating 
them carefully with needles. In this 
way minute threads of tissue are ob- 
tained. If one of these be ex- 
amined with a microscope it will 
be found to consist of many smaller 
threads, called muscular fibers. In 
Fig. 71, four of these fibers are 
seen side by side, with their ac- 
companying blood vessels. In this 
figure and also in Fig. 72, fine 
lines are noticed running directly 
across each fiber. Because of these 
markings this variety of muscle 
has been called striated muscle. 
On examining any piece of lean meat the bundles are 
seen as strings of red flesh, with white connective tis- 
Fig. 72. A muscular 
fiber, showing the nuclei, 
magnified. 
Fig. 73. The capillary blood vessels of muscle, magnified. The draw- 
ing is made from the same specimen as Fig. 71, only the muscular fibers 
are not shown. THE MUSCLES. 
183 
sue between them. Boiling the meat dissolves this con- 
nective tissue to a certain extent, so that the bundles of 
fibers more readily fall apart. 
Structure of Involuntary 
Muscle. Involuntary mus- 
cle is quite simple in its 
structure. In consists of a 
number of spindle-shaped 
cells, held together by a 
cement. This cement sub- 
stance is found throughout 
the body. It is of the na- 
ture of glue, or cement, and 
it firmly holds many of the 
cells of the body together. 
Fig. 74, represents some in- 
voluntary muscle which has 
been treated with dilute acid. The acid has dissolved 
the cement, and the cells are seen well separated from 
each other. These cells are very minute, and a high 
power of the microscope is required to see them. 
The Tendons. The voluntary muscles are sometimes 
attached directly to the skin and to other soft tissues; 
but the great majority are connected to the bones by 
firm, white cords. These white, shining cords are 
called tendons. The tendons have no power of them- 
selves to contract. They simply serve the purpose of 
cords, connecting the working part of the muscle with 
the part which it lias to move. The parts acted upon 
may be removed a considerable distance from the body 
of the muscle; thus, the ends of the fingers are moved 
by the muscles of the forearm. The tendons serve 
Fig. 74. The cells of involuntary 
muscle, magnified. 184 
THE ESSENTIALS OF HEALTH. 
another purpose: owing to their compact nature they 
occupy much less room than do the muscles, and thus 
the size of the wrist and ankle is much reduced. Were 
it not for this fact these joints would be covered with 
thick muscle, and it would be quite impossible to have 
the necessary freedom of motion. The tendons can be 
easily felt at the wrist, while the one attached to the 
thumb is easily seen on the back of the hand. The 
largest tendon in the body connects certain muscles on 
the back of the leg with the heel. Its attachment is 
shown at T, in Fig. 63. It is called 
the “tendo Achilles,” from the 
Grecian fiction that it was at this 
point that Achilles received his 
death wound, as there was no 
other portion of his body that 
could be wounded. 
Fig. 75 illustrates the muscles 
of the forearm, and their tendons. 
The tendons are held tightly down 
at the wrist by firm bands of tissue. 
Some of the tendons extend to the 
very ends of the fingers, so that 
when the muscles of the forearm 
contract, they move the most dis- 
tant parts of the hand. The ten- 
dons are inclosed in sheaths, 
through which they easily glide. 
Muscular Contraction. By placing 
the fingers of one hand upon the fleshy part of the 
other hand at the base of the thumb (the ball of the 
thumb), the tissue will feel soft and comparatively 
Fig. 75. The muscles 
of the arm, ending in the 
white tendons at the wrist. THE MUSCLES. 
185 
thin. This tissue consists of voluntary muscle and can 
be made to contract by an effort of the will. With 
the fingers still in the position indicated, place the 
thumb on the end of the little finger; the muscle now 
feels thick and hard. From this we conclude that when 
a muscle contracts it becomes thicker and harder. We 
know a muscle shortens when it contracts, because it 
moves the parts to which it is attached. 
Fig. 76. a, a muscle relaxed, before it contracts : b, the same muscle, 
contracted ; it is shorter and thicker. 
A slight study of Figs. 77 and 78 will illustrate the 
principle upon which all voluntary muscles act. If 
the muscles on the front of the arm should shorten, 
the hand would be raised ; while if the opposing mus- 
cles, on the back of the arm, should shorten, the hand 
would he drawn down again. If the muscles on the 
front of the leg should shorten, the toes would be 
raised; while the opposing muscles would raise the 
heel. Thus we learn that when a muscle contracts it 
becomes thicker, harder, and shorter; and that all the 
movements of the body are caused by such contractions. 
In the case of the involuntary muscles, the individual 
spindle-shaped cells contract. If the cells be arranged 
in a circular manner, as around the arteries, then their 
contraction will diminish the size of the vessel. For the 
same reason, if the muscular cells that form the walls of 186 
THE ESSENTIALS OF HEALTH 
the stomach contract, they will diminish the size of the 
cavity, and will force out its contents. 
But a muscle cannot remain in a state of contrac- 
tion for any great length of time. It soon tires and is 
Fig. 77. Muscles of the arm : s, the shoulder ; E, the elbow; H, the 
hand ; m, muscles. Fig. 78. Muscles of the leg. 
Diagrams illustrating the action of muscles. 
obliged to relax. After a short rest, however, it is again 
ready for work. All muscles must have rest or they 
will soon wear out. We learned on page 110 that even 
the most active of muscles, the heart, has a brief period 
of rest between its beats. We find that it is very tire- 
some to stand in one position for a long time, because, 
from continued tension, the muscles soon become fa- 
tigued, while a change in the position brings rest. For 
this reason it is much easier to continue walking, for a 
certain length of time, than to remain in one position 
equally as long. TIIE MUSCI.ES. 
187 
Harmony in Muscular Action. The muscles which bend, 
or flex, the joints are called the flexors; while those 
which bring the bent parts back again, are called the 
extensors. Examples of the former are those muscles 
on the front of the arm which bend the forearm ; while 
examples of the latter are those on the back of the arm 
which pull the bent arm straight again. 
From this description it is evident that opposing mus- 
cles must not act at the same time; for if the flexors 
and extensors should equally contract, and pull upon 
the parts to which they are attached, there would be 
no motion whatever. To give free motion to a part, the 
opposing muscles must be finely adjusted to each other. 
In cases of spasms, or convulsions, the muscles do not 
act in harmony, and the body becomes stiff and rigid. 
The delicacy of the adjustment of muscular action is 
well illustrated in the muscles of the face. Often the 
expressions of the face tell more than do uttered words. 
An unconscious contraction of a muscle, be it ever so 
slight, may convey, to the close observer, pain or pleas- 
ure. A slight contraction of a muscle lifts the brow, and 
a smile covers the face ; while a change in another mus- 
cle is followed with a picture of suffering and pain. As 
a general rule, each muscle has a distinct motion to per- 
form. It is also true that any one motion is usually 
brought about by the combined action of several mus- 
cles. The infinite variety of tones that can be produced 
by the human voice is due to the position and tension of 
the vocal cords, and these are controlled by muscular 
action. 
The Control of the Muscles. All the muscles are under 
the control of the nervous system. The nerves serve as 188 
THE ESSENTIALS OF HEALTH. 
a connecting medium between the brain and the spinal 
cord, and the distant muscles. The nerve force is sent 
from the brain, or spinal cord, down the nerve fibers to 
the distant muscles stimulating them to contract. If 
this connection be broken, there will be no muscular 
action. It is possible, however, to make a muscle con- 
tract under such a condition, by applying the proper 
kind of force from without. 
Electricity might make a muscle contract when it had 
no connection with the brain or spinal cord. It is even 
possible to make a muscle contract, after it has been 
removed from the body, by striking it a sharp blow or by 
applying the electric current. But no force originating 
within the nerve centers can reach the muscles, unless 
the nerves leading to them be intact. 
Standing. The ordinary act of standing, like so many 
simple acts, is a result of the most varied and com- 
plicated conditions. Many opposite, or antagonistic, 
sets of muscles contract and thus keep the joints rigid. 
The flexors and extensors must equally contract; for if 
one set should contract with more power than the other, 
the body would surely fall. The young child finds 
great difficulty in standing alone. The skeleton is not 
only weak, but it appears quite impossible for the op- 
posing sets of muscles to contract with equal power; 
therefore the child has to think what he is doing, and 
the task is a hard one. After the habit of performing 
certain acts is formed, the muscles do their work with- 
out our being conscious of what they are doing. QUESTIONS. 
189 
QUESTIONS FOR CHAPTER XVI. 
1. What purposes are served by the skeleton ? Compare. 
2. How many bones of the skull ? How divided ? 
3. Describe one of the vertebrae. 
4. Where is the atlas ? What passes through its openings ? 
5. Where is the axis? Its peculiar feature? 
6. How many ribs are there? How attached to the sternum ? 
7. Describe the bones of the upper extremity. 
8. Describe those of the lower extremity. 
9. Of what use is- the arch of the foot ? 
10. How are the joints kept moist? 
11. Of what use are ligaments? Injuries to them cause what? 
12. Name the varieties of joints. Illustrate. 
13. Where can each variety be found ? 
QUESTIONS FOR CHAPTER XVII. 
1. Give a general description of the muscles. 
2. Name the varieties of muscle. Why so called? 
3. Give examples of each variety. 
4. Give some of the uses of muscle. 
5. Of what is voluntary muscle composed? 
6. Describe the structure of involuntary muscle. 
7. Where are tendons found? 
8. Of what use are they? 
9. How illustrate the contraction of muscles of the thumb? 
10. This experiment shows what ? 
11. Why is it tiresome to stand long in one position ? 
12. How do we know a muscle shortens when it contracts? 
13. Do all muscles require rest? Why? 
14. What muscles are flexors? Extensors? Give examples. 
15. The muscles are controlled by what? 
16. What relation do the muscles bear to the nerves? 190 
THE ESSENTIALS OF HEALTH. 
SUGGESTIONS TO TEACHERS. 
1. Voluntary Muscle. Any lean meat represents volun- 
tary muscle. . Notice the bundles of fibers, and the white 
connective tissue extending around and through the 
muscle. 
2. Tendon. A tendon is easily procured at the market. 
Notice how hard and unyielding it is. The muscles on the 
leg of a fowl show the tendons well. 
3. Action of Voluntary Muscle. To illustrate the action 
of voluntary muscle, attached to bone, follow the directions 
on page 185, under the heading of “ muscular contraction.” 
Tor voluntary muscle not attached to bone, have the pupil 
pronounce the letter U; the voluntary muscle forming 
the fleshy part of the lips contracts. Follow this with 
the pronunciation of the letter Y, and the former muscles 
will relax. 
4. Involuntary Muscle. The heart furnishes the best 
illustration of an involuntary muscle. 
5. Muscular Fibers. Boiled corned beef shows the mus- 
cle, as if ready to separate into small bundles. Needles 
will tear the bundles into finer ones, while the microscope 
will show the smallest bundles composed of minute fibers. 
6. Expression. A variety of experiments can be made 
to illustrate the fact that the various expressions of the 
face, as fear, courage, grief, joy, pleasure, displeasure, etc., 
are caused by the contraction of muscles. EXERCISE. 
191 
CHAPTER XVIII. 
EXERCISE. 
The Necessity of Exercise. The blacksmith always has 
large arms, and the arm he uses the most will be the 
larger. This has been brought about by long and con- 
stant exercise of the muscles. It is only an instance 
showing that the exercise of a muscle makes it larger, 
harder, and stronger. If, for any reason, a person should 
be unable to use the arm for a few months, it would 
gradually become smaller and smaller; and if left 
unused long enough the muscles would nearly all dis- 
appear. This is illustrated in the following case : The 
arm of a young man had become completely paralyzed 
as a result of an injury, and so could not be used. All 
forms of medical treatment failed to restore any power 
of contraction to the muscles. In three years after the 
injury the person died of some acute trouble. A care- 
ful examination was made to find the muscles of the 
paralyzed arm. They had nearly all disappeared, but 
the small portions that remained were examined with 
the microscope. In place of the regular muscular 
fibers there wrere fibers nearly turned to fat, as repre- 
sented in Fig. 79. Disuse of the fibers had caused 
them to undergo a fatty degeneration. From this and 
other facts, we conclude that exercise of the muscles 192 
THE ESSENTIALS OF HEALTH. 
is absolutely necessary to keep them healthy and 
strong. 
But no one admires a man who is all muscle, and who 
has no brain; so we conclude that 
it is unwise to develop one par- 
ticular part of the body and to 
neglect some other portion. The 
endeavor should be to develop all 
parts equally well. A proper 
amount of exercise is one of the 
essential conditions for the accom- 
plishment of this end. 
Many a young and enthusiastic 
scholar has been so carried away 
with his desire for mental advance- 
ment that every hour spent in other 
labor, or in rest, was regarded as 
so much time wasted. He failed to 
remember that the sound mind must 
be in a sound body to bring forth its 
highest and best results. It is to 
this class of devoted workers that we 
earnestly appeal. To all such we 
say, it is of vital importance that at 
least one or two hours of each day 
be spent in outdoor exercise. 
Fig. 79. Two muscu- 
lar fibers undergoing a 
fatty change, magnified. 
The fiber to the left has 
a number of fat globules 
gathered near the nuclei. 
The changes in the fiber 
to the right are more ad- 
vanced : the transverse 
lines have nearly disap- 
peared ; the nuclei are 
scarcely visible ; and the 
whole muscle substance 
is nearly all changed to 
fat. 
General Exercise. Exercise should be taken out of 
doors as much as is possible, since pure air is of the 
greatest importance. No matter Iioav cold the air may 
be outside, no one need fear taking cold if the body be 
kept in active exercise while exposed, and if rest be 
taken in the warm house. EXERCISE. 
193 
General exercise should not be too violent; over-ex- 
ercise is nearly as bad as no exercise. Any exercise 
is too violent which leaves the body “ all tired out.” 
Such exercise unfits the body for regular work, and 
may prove injurious to the nervous system. Healthful 
exercise should bring a restful feeling, a desire for work, 
and refreshing sleep. 
Work and Rest. Each time a muscle contracts there 
is a waste of some of its substance. During the active 
work of a muscle, the waste far exceeds the repair. 
The worn-out material accumulates faster than it can 
be carried away, and the body experiences a sense of 
fatigue. If exercise be continued until the body is 
greatly fatigued, and if such exercise be frequently 
repeated, the muscles will gradually waste away as 
though they were not used at all. 
If a muscle be made to work, it must have its periods 
of rest. The heart never appears to be tired. It beats 
on, year after year, with an astonishing regularity. But 
it would soon wear out did it not have a period of com- 
plete rest between its beats. In order that the muscles 
may be kept in a healthy condition there should be 
proper exercise followed by repose. 
The Amount of Exercise. If exercise be so important 
for the general health, what is to be considered a proper 
amount ? This varies within wide limits, according to 
the health and habits of the individual. If the organs 
and tissues of the body are poorly nourished, so that 
even slight exercise gives great fatigue, then the ex- 
ercise should be very short, and followed by long rest. 
But the fatigue following the exercise of those in deli- 
cate health will grow less and less if the exercise be 194 
THE ESSENTIALS OF HEALTH. 
steadily continued ; always remembering to rest as soon 
as one begins to feel tired. On the other hand, a 
healthy body will exercise until all the muscles are 
thoroughly tired ; and yet, after a night of sound sleep 
will awake feeling all the better for the work. 
Forms of Exercise. Walking is the gentlest form of 
active exercise. It throws into action nearly all the 
larger muscles of the body, except those of the arms. 
The advantage of this form of exercise, over gymnastics, 
is that it takes the person out of doors. Here the 
varied scenery has its exhilarating effect on the nervous 
system, and purer air is inhaled. To derive the full 
benefit of walking, it should be undertaken with a feel- 
ing of freedom and pleasure, and not simply because 
it has been prescribed by a physician ; otherwise, the 
exercise becomes so much hard work, and much of its 
benefit is thereby lost. Therefore it is better that this 
kind of exercise be given to the young in the form of 
games ; for that exercise is best which combines pleas- 
ure with muscular action. 
Rowing is a very healthful exercise, and tends to de- 
velop many parts of the body. It is likely to prove 
injurious when long continued at a time, and when the 
muscles are used too violently. Horseback riding is an 
excellent exercise. It brings into play nearly all the 
muscles, wdiile the fresh air and changing scenery im- 
part a healthy tone to the entire nervous system. 
Out-door exercise of some kind is always to be pre- 
ferred to that taken indoors. How to find plenty of 
exercise in the open air does not trouble the farmer’s 
boy, who has to get up early in the morning, do his 
part of the chores, and then walk a long way to school. EXERCISE. 
195 
But he is the boy who eats heartily, sleeps well, and is 
not easily fatigued. He is laying the sure foundation for 
a healthy body. While it is true that any work which 
brings the muscles into play develops and strengthens 
them, yet it is equally true that “ all work and no play 
makes Jack a dull boy.” Therefore we enter a plea in 
favor of the ball and the racket for summer; and the 
sled, the skates, and the snowballs for winter. 
Benefits of Exercise. The muscles are not the only 
parts benefited by exercise ; the general health of the 
entire body is greatly promoted. Were this not true, 
but little would be said about muscular exercise ; for 
simply to become physically strong should not be our 
highest ambition. “ The pen is mightier than the 
sword.” The mind of man is more to be admired than 
his muscular strength. It is because a healthy body is 
such a great aid to a vigorous mind, that an abundance 
of exercise is so persistently urged. 
A proper amount of exercise increases the healthy 
action of the heart, and makes the blood flow more 
freely through the organs and tissues. It brings more 
air into the lungs, increases the appetite, and aids 
digestion. From this it logically follows that bodily 
exercise tends to give more activity to the mind, and to 
strengthen the mental powers. As the mind grows and 
expands it ought, under proper guidance, to bring forth 
all that is highest and best in man. Knowing these 
things, it is astonishing to us how any person can delib- 
erately take into his system such poisons as alcohol and 
nicotine. He who indulges in these poisons is running 
the fearful risk of undermining not only the health of 
his body, but also the strength of his mental and moral 
nature. 196 
THE ESSENTIALS OF HEALTH. 
When and How to Exercise. Vigorous exercise should 
never be taken either just before or just after a meal. A 
better time for exercise is when the stomach has about 
completed its work of digestion. A short walk before 
breakfast may give an appetite for the morning meal; 
but no very active work should be done until after food 
has been taken. A sudden increase in the amount of 
exercise is to be avoided. Excessive running, heavy 
lifting, and prolonged violent exercise of any kind are 
liable to be very injurious to those who have not been 
gradually brought up to such tests of strength. Pun- 
ning a race, or violently rowing a boat, by those who are 
unaccustomed to active exercise, might result in great 
harm. Exercise should be taken regularly, and then 
gradually increased. Never should attempts be made 
to far excel all former efforts. Let the body be grad- 
ually trained to withstand the severest tests ; then the 
heart and lungs will not suffer from over-exertion. 
Physiognomy. Physiognomy is the art of discovering 
the ruling temper, or other qualities of the mind, by the 
external signs of the countenance. There seems to be 
some relation between the expressions of the counte- 
nance, and the qualities of the mind. Is there any 
physiological explanation of this relation ? It has been 
stated that the expressions of the face are caused by 
muscular contractions, and we already know that a mus 
cle is strengthened by exercise ; therefore those muscles 
which are used the most constantly will be the strongest. 
The explanation of the constant expression of the face 
is based on these facts. If the muscles that are used 
when we laugh are made to contract a great deal, and 
those used when we frown are exercised but little, then EXERCISE. 
197 
the former will become the stronger, while the latter 
will remain weak and undeveloped. This may become 
so marked that when a person is not thinking of laugh- 
ing, the muscles still exert an influence, and there will 
remain a slight expression of laughter on the face. Such 
persons are said to wear a pleasant smile and a cheerful 
face. But suppose grief or pain has caused a person to 
cry a great deal; then there is left on the countenance 
an expression of pain or sadness. If one is in the habit 
of being cross and sullen, it will show in the expression 
of the face. 
Thus, we conclude, the expression which is most con- 
stantly on the face is likely to become the permanent 
one. This is the reason why the face often tells so much 
of the true character. It is within the power of every 
person to conquer an irritable temper, and transform it 
into one of kindness and patience. This is not done sim- 
ply by changing the expression on the face, but rather 
by filling the mind with true and noble thoughts ; by cul- 
tivating those sentiments which are kind and charitable ; 
and by promptly checking the uprisings of a quick tem- 
per. The expression is but the index of the force behind, 
a slight indication of the ruling thoughts and feelings. 
ALCOHOL AND MUSCLE. 
Perhaps no question connected with the study of 
alcohol is of more importance than the relation it bears 
to muscular activity. The man who is laboring hard, 
using his muscles many hours a day, wants to know if 
there is not something he can take which will tone up 198 
THE ESSENTIALS OF HEALTH. 
his tired muscles, and make them stronger. He desires 
to do more work and to do it more easily and more 
quickly. Many a laboring man thinks he cannot begin 
his day’s work without a morning “ tonic ; ” in the mid- 
dle of the day he must have more, in order to go through 
the afternoon; while at night, more must be taken to 
drive away the tired feelings of the day. Is there an 
extra amount of work to be done ? Then he resorts at 
once to some form of alcohol to carry him through the 
double labor. 
The question is, Does alcohol increase muscular 
strength? The correct answer to this must be based 
upon carefully conducted scientific experiments, and 
confirmed by the widest observation among men. If 
alcohol does not increase the strength, why is it that 
so many declare it has this power ? The workman in 
the shop says: “ After taking a glass of beer, whiskey, 
or brandy I feel stronger and better able to work.” Two 
questions must be considered as relating to this state- 
ment. First, is he actually made stronger, and second, 
are his feelings a true guide ? We must admit that if 
alcohol will do no harm to any part of the body, and 
will impart strength to the muscles, it is greatly to be 
desired. To prove the correctness or incorrectness of 
the statement just quoted, it is necessary to study the 
effects of alcohol elsewhere. We cannot accept wdrnt he 
alone says, for he is already under the influence of the 
drug, and as we shall see later is therefore unable to 
decide impartially. 
As a result of the rtiost carefully conducted experi- 
ments, it is proved, beyond a doubt, that both small and 
large doses of alcohol reduce the power of the muscles. EXERCISE. 
199 
Experiments have been made on soldiers who were given 
a fixed amount of work to accomplish. On certain days 
they were given some form of alcoholic drink, and on 
those days they were unable to work either so long or 
so well. Benjamin Franklin, when a poor printer boy, 
in London, was called the “ American aquatic,” because 
he drank only water, while his associates always drank 
beer. To prove to them that his “ loaf of bread and 
pint of cold water ” had more strength in them than 
their pint of beer, he carried a large form of type in 
each hand, up and down stairs, while his fellows could 
carry but one. 
Experiments on individual men, and on companies of 
men, and extensive observation among men, prove, be- 
yond doubt, that when the system is under the influence 
of alcohol, the muscles cannot exert their full power. 
The man who takes alcohol to increase his strength robs 
himself of muscular power. This may be a pleasant or 
an unpleasant fact; nevertheless, it is one which science 
teaches and observation confirms. Four words contain 
the sum and substance of the whole matter: Alcohol 
weakens the muscles. 
But why rely upon our statements alone for proof ? 
If we should make the statement that you could not 
possibly eat enough fruit or rich food of any kind to 
do you harm, you would reply that you know better. 
Your observation among your acquaintances is such 
that you could tell us of numerous instances where 
persons were made ill by over-eating fruit or indigesti- 
ble food. Therefore, we say, look about you; and draw 
your conclusions from your own observation. 
Did you ever see an intoxicated man ? We hope not; 200 
THE ESSENTIALS OF HEALTH. 
but if you have, that one sad observation will make you 
decide the whole question. The manner of walking, the 
bent form, and the thick tongue, show the weakening of 
the muscles. For most positive and unmistakable proof, 
wait for the still further effect, when the whole body 
staggers, and, at last, falls to the ground. What is the 
result of this observation? Is this unfortunate man now 
stronger or weaker ? 
Remember that the change from the full strength of a 
muscle, free from alcohol, to the weak muscle of the in- 
toxicated man is one gradual and steady decline. Now, 
if the facts above stated have been carefully observed 
and considered, the conclusion is irresistible that one 
glass of an alcoholic beverage weakens the strength; 
that two glasses diminish the strength still more; that 
three bring it still lower ; and that with continued repeti- 
tions it must be seriously impaired or entirely overcome. 
Finding that alcohol does not increase the muscular 
strength, we have the other question to answer : Why is 
it, then, so many people declare that alcoholic drinks 
make them feel stronger ? 
We cannot deny their testimony; yet how can we 
reconcile it with what we know to be the truth ? The 
whole trouble is just here ; alcohol is a narcotic, be- 
numbing or diminishing the sensibility of the brain 
and nerves. The nerves should report to the brain 
the condition of the muscles; but when the tired man 
takes an alcoholic liquor these reporters, the nerves, 
and their great center, the brain, are deadened and un- 
able to give or receive an accurate report, — the inability 
varying in proportion to the amount of alcohol taken. 
This may be so marked that the person becomes quite EXERCISE. 
201 
gay and light-hearted; the feeling of weariness or de- 
pression is gone because the nerves are deadened by 
alcohol. But it is only the feeling that is gone. Let the 
man test his strength and he can lift no more, indeed 
not so much, and when the deadening effect of the nar- 
cotic has passed off he will feel all the more exhausted. 
It will be a great day for America when all people under- 
stand the weakening power of alcohol. We believe there 
are many thousands of men using strong drink, who 
would stop it at once, if they only knew its power to 
lower their ability to earn a livelihood. We live in a 
country where the hardest and the best labor will surely 
win. Do you wish to get to the top ? You will need all 
your powers, mental and physical. Alcohol will be as 
an immense ball and chain fastened to your ankle while 
you run to win the race. 
We must remember another physiological fact: to 
grow fleshy is not to grow strong. In athletic sports, 
notice how the men who are to run in a foot race or to 
row in a boat race, always train and diet for weeks in 
order to get rid of their surplus fat, and to develop their 
muscles. Fleshy people, as a rule, are neither so healthy 
nor so strong as those wTho have less fat and more hard 
muscle. An excessive amount of fat is one of the causes 
of the “ fatty heart ” so common among beer-drinkers. 
Much fat causes a disturbance in the action of the liver, 
and is a hindrance to the proper action of the muscles. 
Therefore, it is nothing in favor of beer that it makes 
some persons fleshy. Beer never increases muscular 
strength. 202 
THE ESSENTIALS OF HEALTH. 
CHAPTEK XIX. 
THE SKIN. 
General Description. The skin forms a strong, close- 
fitting garment, protecting the delicate and sensitive 
parts beneath. The skin is not fastened tightly to the 
tissues; it is held by delicate bands of tissue, which are 
of a loose or open nature. This allows the skin to be 
raised and gathered in folds. It also permits free move- 
ments of the skin over the joints and muscles. In some 
parts of the body, as the soles of the feet, and the palms 
of the hands, it acts as an elastic pad. It affords pro- 
tection against external injuries, both from those of a 
mechanical nature, and from the action of chemicals or 
poisonous agents. In the case of a medium-sized man, 
the skin is equal to sixteen square feet of surface. 
Adipose Tissue. The connective tissue beneath the 
skin usually contains more or less adipose, or fatty 
tissue. In thin persons there may be very little fat, 
and the outlines of the tendons and muscles, and even 
the shape of the bones may show through the skin. 
In fleshy persons the fat may be in great abundance, 
pushing out the skin, and causing the wrinkles and out- 
lines of the parts beneath to disappear. In the average 
healthy body there is always some fat in the tissues 
beneath the skin. In old age the fat is likely to disap- THE SKIN 
203 
pear, causing the skin to form in folds or wrinkles. 
The fatty tissue is of use as an aid in retaining the 
heat of the body, thus taking the place of so much 
extra clothing. 
The fat is formed directly from the connective tissue. 
This tissue is composed of fibers and cells. Many of 
the cells are of the 
shape represented in 
Fig. 80. When the 
body is accumulating 
fat, small fatty or 
oily particles appear 
in these cells. Later 
these minute glob- 
ules of fat increase 
in size and number 
until they run to- 
gether as two drops of oil unite making one drop. Still 
later the entire cell becomes filled with the fat, giving 
the appearance of one large 
spherical body, holding a 
large fat globule. The con- 
nective tissue-cells thus 
become greatly distended 
and thereby increased in 
size. When the fat in the 
body is being reduced by 
disease or starvation, it 
gradually disappears from the cells. 
The Epidermis. The skin is composed of two layers, 
the epidermis and the dermis. The epidermis, which is 
also called the cuticle, or false skin, forms the outer 
Fig. 80. Cells from connective tissue, mag- 
nified. 
Fig. 81. Fat cells, magnified: 
to the right are five connective tis- 
sue-cells partly filled with fat. 204 
THE ESSENTIALS OF HEALTH. 
layer. It is composed entirely of cells, the outer ones 
being very hard and dry. The cells are arranged many 
layers deep ; through them pass the ducts of the sweat 
glands, the oil glands, and the hair shafts. Fig. 82 shows 
Fig. 82. A section of the epidermis, magnified : A, the layer of cells 
nearest the dermis ; r», the layer nearest the surface of the body. 
the microscopical structure of the epidermis. The outer 
cells at D have no nuclei, are very hard and dry, and are 
being constantly removed as mentioned below. The epi- 
dermis has neither blood vessels nor nerves ; it is, there- 
fore, bloodless and without feeling. For these reasons it 
is possible to remove nearly all the epidermis by gently 
scraping the skin with a knife without causing pain or the 
flow of blood. But as soon as the true skin, the dermis, 
is reached, the scraping brings both pain and blood. 
The epidermis is removed entire from the dermis by a 
blister. An ordinary blister on the hand shows a thin 
membrane, raised from the parts beneath, and separated 
from them by a watery fluid. Such a membrane may 
be cut without pain or blood ; for it is the epidermis of 
the skin. After the thin membrane is removed, if the THE SKIN. 
205 
red surface beneath it be touched it will be found highly 
sensitive and easily made to bleed. 
Epidermis Rapidly Changing. The epidermis is a good 
illustration of the wear and waste of the body. The 
outer cells are constantly falling off in vast numbers ; 
immense numbers are removed daily by the friction of 
the clothing, and by the work of the sponge and towel 
at the bath. This great loss is being steadily made up 
by the formation of new cells in the deeper parts ; these 
come to the surface as the ones over them disappear. 
If all of the epidermis were removed at once the parts 
left would be very red and tender; but in the case of 
the blister, a few cells of the epidermis are left cling- 
ing to the true skin ; these rapidly multiply until within 
a few days a complete new epidermis is formed. After 
some fevers, as during the “peeling” of scarlet fever, 
large masses of cells are removed together. 
The Coloring of the Skin. The color of the skin de- 
pends largely upon the character of the deepest cells of 
the epidermis, as at A, Fig. 82. In very light skins 
these cells are colorless, in darker skins the cells have 
a slight amount of dark coloring matter in them ; while 
in the darkest skins, the coloring matter is very abun- 
dant. A destruction of these deep cells causes the 
epidermis to appear perfectly white, as it does in certain 
diseases. The white skin of the Albinos is due to the 
absence of any coloring matter in these cells. A free 
supply of blood to the skin gives it a red or pink color ; 
while any interference with the action of the liver may 
give a jaundiced, or yellow color to the skin. 
Uses of Epidermis. The outer layer of cells of the 
epidermis, as seen at D, Fig. 82, consists of closely 206 
THE ESSENTIALS OF HEALTH. 
packed, hard cells which make a very complete and 
almost impenetrable covering. Therefore, the epidermis 
is a protection against the absorption of poisons. The 
physician understands this; for if he wishes to intro- 
duce medicine into the system by the skin, he first 
scrapes off the epidermis, or removes it with a blister, 
and then sprinkles on the drug. I11 vaccinating, it is 
necessary to remove the epidermis, in order that the 
virus may come in contact with the absorbent vessels 
beneath. 
The surgeon is not harmed while operating on dis- 
eased portions of the body, because the epidermis pre- 
vents the absorption of any decaying matter ; but a few 
cases are on record where the skin on the surgeon’s 
hand was accidentally cut or broken while operating, 
thus allowing diseased matter to be absorbed, producing 
blood poisoning and even death. Immersing the whole 
hand in poisonous matter might possibly do no harm, 
provided the epidermis were in a perfect condition every- 
where ; but the slightest prick of the finest needle might 
then be the cause of death. The epidermis also pro- 
tects the parts beneath from the sudden changes of heat 
and cold. 
The Tactile Bodies. The tactile bodies give the sense 
of touch. They are situated in the dermis, or true skin ; 
they reach to the epidermis but do not penetrate it. 
Wherever the sense of touch is the most delicate, there 
are found the largest number of tactile bodies. Over one 
hundred of these bodies have been counted in a space 
-gV of an inch square. They are very small, averaging 
no larger than g-i-g of an inch in length. Thus the mi- 
croscope shows that while it is true that the epidermis THE SKIN. 
207 
has neither blood vessels nor nerves, yet just beneath it 
are nerves especially arranged for the sense of touch. 
These tactile bodies are illustrated at 4, Fig. 83. The 
dermis is also well supplied with blood vessels. 
Fig. 83. A section of the human skin, magnified : (1) the epidermis ; 
(2) the duct of a sweat gland ; (3) a sweat gland ; (4) the ending of a 
nerve, for the sense of touch ; (5) coils of minute bloodvessels ; (6) a hair 
follicle, in which is a hair ; (7) a muscle, which can move the hair follicle. 
The Sweat Glands. The sweat glands are found in the 
deep parts of the dermis, or in the tissue immediately 
beneath the dermis. In Figs. 83 and 84 these glands 
are represented as minute tubes arranged in circular 
coils. That part of the tube which is not coiled, but 
which extends from the gland to the surface of the skin, 208 
THE ESSENTIALS OF HEALTH. 
is called the duct: the duct pursues a spiral course, as 
represented in Fig. 84, and opens on the surface with a 
funnel-shaped dilatation. 
If the ridges which ap- 
pear so plainly on the ends 
of the fingers and palms 
of the hands, be exam- 
ined with a small magni- 
fying glass, it is possible 
to see the minute depres- 
sions in the center of 
them ; these represent the 
openings of the sweat 
glands. The view ob- 
tained will resemble that 
given in Fig. 85. The 
openings are quite close 
together, in some places 
averaging as many as 
8000 to the square inch. 
From the surface of the 
skin to the coiled glands 
is about one fourth of an 
inch. It is estimated that there are over three millions 
of these glands in the entire skin. 
The Perspiration. The perspiration is a colorless fluid, 
secreted in the coils of the sweat glands. It is of very 
simple composition, over 99.5 per cent of it being water. 
Some inorganic substances, as sodic chloride, common 
salt, give it a salty taste; while some organic ingre- 
dients, as the fatty acids, impart to it an odor. The 
perspiration is a continuous secretion. When it is 
Fig. 84. A portion of Fig. 83. The 
section was prepared especially to show 
the sweat glands and their ducts : (1) 
ducts of the sweat glands ; (2) the 
hair shaft. THE SKIN. 
209 
small in amount, the water is evaporated from the skin 
at once, therefore its presence on the skin is not no- 
ticed; this is called the insensible perspiration. As soon 
as the secretion is increased, it does not all evaporate, 
but gathers as drops of sweat on the surface; this is called 
the sensible perspiration. Many conditions cause the 
amount of perspiration to vary. In some individuals the 
whole amount per day is very small; while in others it 
Fig. 85. The surface of the skin, slightly magnified, showing the 
openings of the sweat glands. 
is very large. It is a fair average for the year through 
to say that from two to four pounds are secreted each 
day. 
There is a marked difference in the perspiration of 
the lower animals; the horse perspires freely ; the ox 
to a slight extent only ; and the dog but little, if any. 
The panting of the dog after exercising allows much 
water to be given off from the body through the lungs; 210 
THE ESSENTIALS OF HEALTH. 
and in this way the object of regulating the temperature 
of the body is gained, as will be described later. 
Controlled by Nerves. The activity of the sweat glands 
is under the control of certain nerves. While it is true 
that dilatation of the blood vessels is usually associated 
with profuse perspiration, yet it is possible to arouse 
these glands into activity even after the supply of blood 
has been cut off. For instance, in cases of great fear, 
when the skin is extremely pale, and its blood vessels 
nearly empty, the face may be covered with great drops 
of perspiration. 
Conditions Affecting Perspiration. An increase in the 
temperature of the surrounding air will cause an in- 
creased secretion of the perspiration. Individuals who 
work in furnaces, or in places of very high temperature, 
often perspire as much in an hour as the average person 
will in a day. Those who perspire freely ought to drink 
a large amount of water to supply the loss, or the sys- 
tem will soon become exhausted. An extra amount of 
water in the system, as there is after a free use of warm 
drinks, will increase the secretion. Muscular activity 
is known by all to do the same. Certain drugs excite 
very copious perspiration, while other drugs diminish it. 
The secretion is lessened by cold ; in fact, it may be 
suddenly arrested by this means. 
The liability to perspire varies greatly in different in- 
dividuals, and in the same individual at different times. 
Any departure from health may cause it to vary from 
the hot, dry skin of fever, to the profuse night-sweats of 
consumption. There is a direct relation existing between 
the kidneys and the skin. In summer when the skin is 
active the secretion of the kidneys is much lessened, while THE SKIN. 
211 
in winter when the skin is less active the work of the 
kidneys is increased. 
Object of the Perspiration. The chief object of the 
perspiration is to regulate the temperature of the body, 
although it removes a slight amount of worn-out material. 
It is well known that when a liquid evaporates it pro- 
duces cold. So the evaporation of a number of pounds 
of water each day from the surface of the body during 
the warm days of summer, causes a considerable lower- 
ing of the temperature. Exercise during the summer 
would be quite impossible were it not for this fact. 
The exercise causes rapid oxidation of the tissues, and 
this produces heat; and added to this is the heated at- 
mosphere. Were not some way provided of cooling the 
body, it would soon be in a raging fever. But the more 
exercise, and the higher the thermometer, so much more 
profuse is the perspiration, while its rapid evaporation 
causes the body to remain at about a fixed degree of heat, 
Checking the Perspiration. Sudden cooling of the skin 
checks its action, throws additional work on other parts 
of the body, and often causes disease. One of the most 
frequent causes of a cold is the sudden checking of the 
perspiration. After exercising, or whenever the body 
is perspiring freely, there should be great care in re- 
gard to draughts of air. The body should be gradually 
cooled, with some light clothing thrown over the 
shoulders, while resting. Sudden checking of the per- 
spiration is positively injurious and may easily lead to 
fatal results. 
The Hair. A hair consists of the root and the shaft. 
The former is situated in the skin, and the latter pro- 
jects from it. The hair may be easily removed from its 212 
THE ESSENTIALS OF HEALTH. 
sac or follicle, without damage. At the lower end of 
each hair is a small eminence, or papilla, which is well 
supplied with blood. The root of the hair rests on this 
papilla and grows therefrom. The cells of the papilla 
multiply and grow, pushing those already formed up- 
wards toward the surface. A hair therefore, grows en- 
tirely from the root, from this minute papilla. If a 
hair be removed, another 
begins to grow at once from 
the papilla, and in time will 
appear on the surface. A 
destruction of the papilla is 
necessary to prevent the hair 
from growing. 
The hair shaft is not hol- 
low, although its center is 
composed of cells more 
loosely arranged than those 
forming the exterior. Hair 
is very elastic; with proper 
care it can be made to 
stretch nearly one third its 
entire length before break- 
ing. It is also very strong, 
— a single hair being capable of suspending a body 
weighing from three to five pounds. 
Fig. 86. Human hair, Fig. 87. A hair 
magnified. from the cat. 
A glance at Figs. 86 and 87 shows that the micro- 
scope reveals a great difference between the hairs of the 
lower animals and those of man. In certain cases the 
difference is very marked, as here shown, while in 
others it is not so marked. These facts have been 
used for the detection of fraud, and other crimes. THE SKIN. 
213 
Muscle of the Hair. In Fig. 83 it is noticed that the 
hair is placed obliquely in the skin. Fastened to the 
Fig. 88. A human hair in its sheath, or follicle, magnified : H, the 
hair shaft; m, the muscle ; G, the oil gland. 
lower part of this hair sac and extending obliquely up- 214 
THE ESSENTIALS OF HEALTH. 
wards and to the left is a muscle. This muscle is better 
shown at M, in Fig. 88. The muscle is thus arranged 
at an acute angle, so that when it contracts, it pulls on 
the base of the hair sac, causing it to stand more nearly 
erect. In this way the hair is made literally “ to stand 
on end.” A contraction of this muscle produces the 
condition known as “ goose skin.” 
The Sebaceous Glands. The sebaceous or oil glands 
are situated by the side of the hair sacs into which they 
open by a duct, as illustrated in Fig. 88 at G. These 
glands secrete an oily substance which is spread around 
the hair making it smooth and glossy. Some of the 
secretion extends over the skin making it soft and thus 
preventing it from becoming hard and dry. Often the 
ducts to these glands become stopped up, and the secre- 
tion distends the glands. This afterwards becomes dark 
colored, disfiguring the skin. 
By referring to Fig. 88, it will be noticed that a seba- 
ceous gland is situated between the hair sac and the 
muscle, M. By the contraction of this muscle the hair is 
drawn toward its upper attachment and the gland thereby 
compressed, thus aiding in forcing out its contents. 
The Nails. The nails grow from behind forward, thus 
being constantly pushed outward. They are composed 
of minute cells, similar to those found in the deeper 
parts of the epidermis, only they are firmer and harder. 
The nails protect the ends of the fingers and toes ; and 
they give aid to the fingers in picking up small objects. 
If a nail be removed by an accident, a new one will take 
its place in a few weeks, providing the root is not 
injured, BATHING. — CLOTHING. 
215 
CHAPTER XX. 
BATHING-. — CLOTHING. 
necessity of Bathing. We know that an immense num- 
ber of sweat glands are constantly pouring their secre- 
tion on the surface of the skin; that vast numbers of oil 
glands are depositing an oily substance on the surface 
also ; and that the cells of the epidermis are constantly 
loosening and falling off in great numbers. It is only 
necessary to recall these facts, in order to understand 
fully the necessity of frequent bathing. The glands of 
the skin have a certain work to do ; how can they prop- 
erly perform this if their ducts be closed by an accumu- 
lation of such material on the surface ? If these glands 
cannot perform their full duty, then other glands or 
organs must do it for them, or sickness will follow. 
We conclude, therefore, that neglect of the skin means 
more work for the lungs and kidneys, especially for the 
latter. 
Always considered Important. The nations of antiquity 
had much to say about the bath, both as a luxury and as 
a means of preserving the health. The public baths of 
Rome were among the most interesting of her works of 
grandeur and beauty. Most beautiful works of art have 
been recovered from their ruins, all speaking of the 
splendid preparations made for this luxury. The cost of 216 
THE ESSENTIALS OF HEALTH. 
a bath in one of these elegant quarters was almost noth- 
ing, so that all people could enjoy its benefits. After 
bathing, the skin was usually anointed with perfumed 
oil; and this was followed by light exercise for a short 
time. In those days nearly every one could swim; and 
to be unable to swim was about as great a disgrace as to 
be unable to read. 
When to Bathe. Probably immediately after rising in 
the morning is the best time to bathe. The body is 
rested, reaction is easy, and the circulation is at its best. 
The ideal bath is a brief, daily use of cold water, im- 
mediately after rising, followed with a brisk use of the 
towel. One should never bathe when greatly fatigued, 
nor use a cold bath if feeling chilly. Neither should a 
bath be taken immediately before or immediately after a 
hearty meal. It should not be taken soon after a meal, 
because the rubbing brings the blood to the surface, 
and therefore must take some of the blood away from 
the stomach, where it is needed. Great caution should 
be used in bathing when the body is over-heated, and 
when it is perspiring freely; because if the water should 
be too cool, or if the rubbing should fail to produce a 
complete reaction, then a severe cold or something more 
serious might result. Both too cold and too hot water 
are alike injurious. 
The Cold Bath a Tonic. A healthy person should re- 
gard the bath as something more than a cleansing pro- 
cess. It should be a tonic of the most invigorating 
character. The first effect of the cold is to drive the 
blood from the skin; but soon reaction takes place, and 
the blood returns with renewed force, filling the capil- 
laries of the skin, and imparting a healthy glow to the BATHING. — CLOTHING. 
217 
entire surface. Just at this time the bathing should 
cease. The brisk use of the towel heightens the flow 
of blood, and the whole body becomes enveloped with 
a pleasant sense of comfort and warmth. To remain 
longer in the bath would be to send the blood from the 
surface for the second time, from which reaction might 
not occur, causing a sensation of chilliness and fatigue. 
The brisk work of the rubbing causes the exercise of 
many muscles, and the whole body is thereby aroused 
to activity. 
The cold bath is injurious to those who do not have 
a quick reaction from its use. The skin should be left 
red and warm, and the whole system ought to be in- 
vigorated. If not, and the opposite be true, then the 
cold bath is injurious rather than helpful. If the bath 
be short at first, if the water be cool, if it be continued 
daily, if the towel be used briskly, and if only a por- 
tion of the body be bathed at a time, then it must be of 
benefit. Soon the water can be used colder and the 
time of the bath extended. With these precautions in 
mind, it is safe to assert that there are very few young 
people, in fair health, who would not be greatly benefited 
by the daily use of the cold bath. A quick sponge 
bath with cold water, followed by thorough rubbing, is 
the best method to illustrate the advantages and safety 
of the cold bath. 
Salt Water Bathing. Many persons who visit the sea- 
shore plunge into the cold water at once, and remain 
there for a number of minutes. If they have been accus- 
tomed to the cold bath at home, there can be no more 
healthful exercise. The beating of the surf against the 
skin is an invigorating tonic in itself, while the muscles 218 
THE ESSENTIALS OF HEALTH. 
of the whole body are brought into action in withstand- 
ing the force of the waves. The change of scenery and 
the freedom from care aid in imparting new life to the 
seaside resorter. If he be unaccustomed to the cold 
bath, however, and suddenly spends from twenty to 
thirty minutes in the sea, he must expect undesirable 
effects to follow. A vast amount of sickness is caused 
in this way, all of which might be prevented. A person 
should not remain over three minutes in the water at 
first, and then should immediately rub the body briskly 
with a towel, and dress warmly. To such as follow this 
advice sea bathing, in most cases, will be of the greatest 
benefit. The best time for a bath in the sea is before the 
midday lunch, about 11 a. m. This gives time for a nap 
or a short rest before taking food into the stomach. It 
is a great mistake to suppose that one needs to take 
an alcoholic drink of any kind after bathing to prevent 
taking cold. 
Warm Baths. An occasional warm bath, with the use 
of pure soap, is necessary. But warm water should 
not be used for the daily bath, unless advised by a phy- 
sician for the purpose of removing impurities from the 
system through the skin. In such cases the steam 
bath, the Turkish bath, or the Russian bath is often 
prescribed. A daily warm bath lowers the tone of a 
healthy system and diminishes its power to withstand 
disease. 
How to Bathe, There is always a temptation to have 
the bathing-tub filled with tepid water, and then remain 
in it a long time. But this method deprives the bath of 
its tonic properties. A bath of this description once a 
week may be desirable, but is most undesirable for daily BATHING. — CLOTHING. 
219 
use. The better method is to use the hands, or mittens 
made from crash toweling; quickly cover a portion of 
the body with cool or cold water; rub this portion dry ; 
and thus proceed until the bath is completed. The 
whole batli should not exceed five minutes. 
The Value of the Bath. The value of the bath will 
depend largely on the completeness of the reaction fol- 
lowing its use. As stated before, the skin should be 
warm and the whole system refreshed. But if the skin 
be cold, and the body feel chilly and fatigued ; or if the 
bath be followed by headache and general lassitude, 
then the practice should be discontinued, and a physi- 
cian consulted to discover where the error rests. The 
bath is of great value to those who are already w'ell and 
strong; it is to such that its use is so freely recom- 
mended. It is of great value in keeping the various 
organs and tissues of the body in a healthy condition, 
and it is therefore a good preventive of disease. The 
aged and the feeble need special advice for their particu- 
lar cases ; and the bath should be used by them only 
under the advice of a physician. 
A Good Complexion. Bathing is essential if one de- 
sires a good complexion. The skin must be active and 
do its part of the work. Frequent bathing of the face 
with pure water is especially desirable. Soaps are not 
necessary for the face, while their use often causes 
roughness of the skin. Cosmetics almost invariably con- 
tain substances which are injurious to the skin. Their 
continued use often seriously affects the general health. 
The Clothing. One object of the clothing is to prevent 
too great loss of heat from the body. The surround- 
ing atmosphere is nearly always cooler than the body, 220 
THE ESSENTIALS OF HEALTH. 
therefore there is a tendency for the body to lose heat. 
The clothing corrects this tendency in a large measure. 
Food produces the heat and the clothing prevents its 
escape; for this reason it is true that poorly fed persons 
need more clothing in winter than.those who are well 
fed. Animals require less food, and are able to do more 
work, if they are kept warm during the cold weather. 
Protection from the cold economizes the fuel of the 
body, which is the food. Clothing protects the body 
from external injuries, and is also an ornament; but its 
great object is to aid in maintaining an equal tempera- 
ture in the body. 
Nature often Regulates the Clothing. The lower ani- 
mals are unable to alter their clothing to meet the 
change of the seasons; so Nature does the work for 
them. In winter the long fur and the heavy coat of 
hair protect the body from the wind and snow; in the 
spring this is changed, and a thin, light covering takes 
its place. Whether this covering be thick or thin, of 
fur or feathers, it is always a poor conductor of heat. 
A most valuable lesson may be learned from this fact: 
no matter what the outer garments may be, those next 
to the skin should be made of a material that is a poor 
conductor of heat. 
The Materials of Clothing. With the above facts in 
mind, it is natural that furs should be extensively used 
during the cold weather. Next to fur in this respect is 
wool. All woolen garments are poor conductors of heat, 
and are therefore valuable for winter use. Woolen 
garments are a wonderful protection against the cold 
in winter, and during the sudden changes in summer, 
they should be worn next to the skin the entire year. BATHING. — CLOTHING. 
221 
The thick and heavy material can be used during the 
winter, and the thinnest and lightest during the sum- 
mer. If woolen garments irritate the skin, then silk 
may be used, as approaching the nearest to wool. 
These simple precautions in dress will prevent an im- 
mense amount of illness. The sudden changes in tem- 
perature and exposure to draughts would not so often 
be followed by colds, chills, sore throats, and lung 
troubles, if the body were constantly surrounded by 
a non-conducting medium, as wool or silk! Linen is a 
good conductor of heat; therefore, it should not be used 
next to the body. Cotton is much to be preferred to 
linen, and it is much better for bed-clothing. The outer 
garments can be regulated according to the seasons and 
the conditions of the air, but under all circumstances 
keep the surface of the skin well protected with either 
wool or silk. 
The Weight of Clothing. A heavy covering of cotton, 
or linen, is not so warm as a lighter covering of wool or 
silk. The weight of clothing has no definite proportion 
to its warmth. Air is a poor conductor of heat, so is 
wool; hence, it follows, that the light, loose cloud worn by 
ladies as a covering to the head is based upon scientific 
principles. The air in the meshes of the wool, and the 
wool itself, give little chance for the heat to escape. 
Therefore in choosing clothing, the nature of the ma- 
terial should be considered more than its weight, — its 
value as a non-conductor of heat being in the order here 
given : wool, silk, cotton, and linen. 
Clothing should Fit well. It is not conducive to the 
general appearance to have ill-fitting clothing; yet it 
does not follow that tight clothing adds to the appear- 222 
THE ESSENTIALS OF HEALTH. 
ance. To the physiologist, the constricted waist and 
the pinched foot represent ill-fitting clothing decidedly 
more than does the loosest hanging garment. Tight 
belts and corsets are accountable for a long series of 
complaints. Constricting the waist compresses the 
liver and stomach and interferes with the movements 
of the diaphragm ; this often causes headache, dyspepsia, 
shortness of breath, and a multitude of aches and pains. 
Clothing can and should be made to fit well, and yet 
it need not interfere with the action of any organ, or 
with the natural movements of any part. 
Clothing should be Changed. Wet feet are the cause 
of many a sore throat and severe cold ; and for most 
persons, it is a great risk to allow them to remain damp. 
They should be dried and rubbed thoroughly as soon as 
possible, in order to fully restore the circulation. If one 
be caught in a storm so that the clothing becomes damp 
or wet, it should be changed at the first opportunity. 
Brisk exercise in the mean time will keep the body from 
becoming chilled. But if chilly sensations and hot 
flashes are already creeping over the body, probably a 
severe cold is coming on. 
To Cure a Cold. A cold is generally produced, as just 
indicated, by some exposure, so that the skin is inactive 
and the internal organs congested. The mucous mem- 
brane of the nose, throat, larynx, bronchi, and the lungs 
are, one or all, most likely to be affected. During the 
summer the congestion of the internal organs often 
causes a disturbance of the digestive organs. It is 
essential, therefore, to cure a cold at the beginning; 
this can often be done by very simple remedies. The 
object to be accomplished is to restore activity and BATHING. — CLOTHING. 
223 
warmth to the skin. This can be brought about by giv- 
ing hot drinks, and by adding extra clothing. Drink 
slowly a bowlful of hot lemonade, or hot ginger-tea, 
while the feet are in a hot bath, and while an extra 
blanket is thrown over the body. Soon the body will 
perspire freely, and the whole system feel warm from 
the artificial heat. Have the bed-clothing thoroughly 
warmed before getting into bed, and then keep well 
under cover. Remain in this condition until the body 
is thoroughly covered with perspiration, when we can 
be assured the skin has resumed its activity. Have the 
body rubbed dry, and gradually remove the extra cloth- 
ing, in order that the temperature may be slowly low- 
ered. If such simple treatment were more frequently 
and more quickly carried out, a vast amount of illness 
would be prevented. 
1. Give some reasons why frequent bathing is necessary. 
2. When is the best time to bathe ? 
3. Give some cautions about bathing. 
4. Describe the first effect and the reaction of a cold bath. 
5. When is a cold bath injurious? 
6. Give some directions about sea bathing. 
7. What is said about the warm bath ? 
8. The value of a bath depends upon what ? 
9. Why is the bath a good preventive of disease ? 
10. What is one object of the clothing? Explain. 
11. How does nature regulate the clothing of the lower animals? 
12. What material is a poor conductor of heat? 
13. Is heavy clothing necessarily the warmest? 
14. Give directions for curing a cold. 
QUESTIONS. 224 
THE ESSENTIALS OF HEAT AH. 
CHAPTER XXI. 
ANIMAL HEAT. 
Sources of Animal Heat. It has already been stated 
that the heat of the body is derived from the food, and 
from the oxygen obtained during respiration. By the 
union of these, oxidation occurs, and heat is produced. 
It appears from this statement that there must exist a 
relation between the amount of oxygen consumed and 
the amount of heat produced in the body: thus, if an 
animal consumes little oxygen it will have a low tem- 
perature ; if much oxygen, then a higher temperature. 
Another source of heat is from certain physical pro- 
cesses of the body, as the work of the heart, the general 
circulation, and the active exercise of the body. 
The chief source of heat is found in the muscular 
system. The muscles form a large proportion of the 
whole frame, and they are very active during many 
hours of the day. The greater their activity, the more 
rapidly will the tissue be exhausted, and new tissue 
take its place. These changes require the oxidation of 
much food, and thereby much heat is developed. Next 
to the muscles are the secreting glands. Most rapid 
changes occur in these glands when they are active, all 
of which produce heat. The liver is the most important 
gland in producing heat. The changes taking place in ANIMAL HEAT. 
225 
the liver cells are very active and continuous. The 
warmest blood in the body is found just as it leaves the 
liver, on its way to the heart, being much warmer here 
than when it enters the liver. But heat is generated in 
every organ and tissue in the body; as each activity 
contributes to an elevation of the temperature. 
Cold-Blooded and Warm-Blooded Animals. Cold-blooded 
animals are those whose temperature is generally about 
the same as that of the air or water surrounding them. 
They consume little oxygen, and therefore a small 
amount of heat is developed. Frogs, reptiles, and fishes 
have a low temperature, which varies at times between 
wide limits. When the temperature of their surround- 
ings is increased they consume more oxygen, and thus 
develop more heat; while if the temperature be lowered 
the amount of oxygen consumed is diminished, and the 
animal heat reduced. 
During the winter the frog buries himself in the cold 
sand at the bottom of the water, where he receives 
enough oxygen through the pores of the skin to sustain 
life. But during the warmer weather of summer he 
comes to the surface to fill his lungs with air ; this is 
necessary in order to meet the demands of the more 
rapid changes in the tissues of his body. During the 
winter his home is under the water, but during the sum- 
mer he would be drowned if he remained in water, as 
the more rapid oxidations require more oxygen than can 
be supplied through the medium of the skin. 
Warm-blooded animals are those whose temperature 
is generally above that of the surrounding air. They 
maintain a remarkably uniform temperature throughout 
the heat of summer and the cold of winter. A person 226 
THE ESSENTIALS OF HEALTH. 
may ride a long distance in the cold air, or work hard 
in an over-heated room, yet the temperature of his body 
will remain almost at a fixed point. 
Temperature of the Body. The thermometer shows 
that different parts of the body vary in temperature. 
In those parts where rapid changes are taking place, 
and where oxidation is most marked, the temperature 
is much higher than the average for the body. The 
blood is constantly passing from one tissue to another, 
carrying warmth from the tissues where heat is being 
developed to other tissues where it is being lost; thus 
the blood tends to equalize the temperature of all parts 
of the body. The temperature is ascertained by placing 
the bulb of a thermometer under the person’s tongue. 
The loss and production of heat are so evenly balanced 
that the temperature of the healthy adult body varies 
little from 98|° F. This is maintained with only slight 
variation throughout life. So accurately is this ad- 
justed during health that a variation of more than a 
single degree denotes some disturbance in the system ; 
a fall of two degrees below the normal temperature is 
considered a serious matter ; while a severe cold may 
cause it to rise two degrees above normal. A tempera- 
ture above 103° denotes a high fever; of 105° a severe 
attack; above 105° is most alarming ; while recovery 
after the thermometer has recorded 110° is very rare. 
The normal temperature of 98|° F. is subject to some 
variations within narrow limits. There are quite regu- 
lar variations in the course of every twenty-four hours. 
The temperature continues to rise during the day until it 
reaches the highest point from five to eight in the even- 
ing ; then it continues to fall during the night until from ANIMAL HEAT. 
227 
two to six in the morning, when it is at the lowest. 
About the middle of the forenoon, or about three hours 
after the morning meal, the thermometer should record 
98|° F. The difference between the lowest and high- 
est points reached during the day probably does not 
exceed one degree. 
The Regulation of Heat. The question now arises, 
how is the excess of heat above 98|° removed from the 
body ? The body would soon become very much warmer 
were not some means provided for regulating the heat. 
It is estimated an adult body produces, in one hour, 
enough heat to raise the temperature three degrees. If 
no heat were given off, in thirty-six hours it would reach 
the boiling point; hence the distribution and removal of 
the excess of heat becomes an important matter. 
The two principal tissues which regulate the tempera- 
ture are the lungs and the skin. It has been stated that 
the expired air is warmer than the inspired air. There- 
fore considerable heat is required to produce this warmth, 
which is carried out of the body with each expiration. 
The evaporation of the water of the expired air — the 
watery vapor — also produces cold; indeed the loss of 
heat is in definite proportion to the amount of air taken 
into the lungs in a given time. The rapid breathing of 
a dog after running, and the extra flow of water from 
his mouth are illustrations of these facts. 
But the work of the skin is far more important, being 
five times as great as that of the lungs, in this particular. 
It must be evident that the more freely the blood passes 
through the skin, thus coming under the influence of 
the cooler surroundings of the body, so much the 
greater will be the loss of heat. The evaporation of 228 
THE ESSENTIALS OF HEALTH. 
the perspiration results also in a great loss of heat to 
the body. 
This regulation of the heat is well illustrated by study- 
ing the changes which take place during some active ex- 
ercise. Muscular contraction gives rise to heat; hence 
exercise must increase the bodily temperature. But the 
thermometer shows no such change; what then becomes 
of the heat thus produced ? The exercise causes rapid 
breathing, and hence more loss of heat through the 
lungs; while more blood is sent to the skin, where its 
temperature is lowered. The exercise also causes the 
skin to perspire freely, and the evaporation of the water 
from the surface of the body results in a great loss of 
heat. Thus we find that the extra amount of heat 
caused by muscular exertion is completely lost by the 
increased action of the lungs and skin; and as a result, 
the temperature of the body remains at a fixed point. 
Effects of Lowering the Temperature. The body is 
warmed by heat generated within itself. To lower its 
temperature, it is only necessary to abstract the heat 
faster than it can be produced. The first effect of this 
is pain in the more exposed parts. The face and ex- 
tremities “ ache with the cold.” This soon passes away 
and the skin becomes quite insensible. The testimony 
of individuals who have been rescued from freezing, 
even after they were insensible from the cold, is that 
a disposition to sleep overtakes them soon after the pain 
has left the skin ; the muscles become inactive; breath- 
ing is slow and difficult; and the whole nervous system 
becomes sluggish. Finally, the desire to sleep becomes 
irresistible, and in a short time death ensues. When 
rescued from a freezing condition, it is found that res- ANIMAL HEAT. 
229 
piration is hardly perceptible, the heart’s action ex- 
tremely weak, and all the functions of the body nearly 
suspended. 
The above condition is very similar to a normal 
physiological process among the so-called hibernating 
animals. These animals go to sleep at the approach 
of winter, and do not waken until the coming of 
spring. When found, buried in their nests, or deep un- 
derground, they are quite insensible and immovable. 
Their respiration is hardly discernible, and their bodily 
temperature is much reduced. The oxidation of tissue 
is very slight, and the animal appears to live by using 
up its own flesh, — entering upon sleep well supplied with 
fatty tissue and awakening in the spring very poor. 
Effects of Raising the Temperature. When the animal 
heat is raised a number of degrees, as in fevers, the 
effects are quite the reverse of those produced by cold. 
In fevers, the pulse and the respiration are increased in 
frequency, and instead of a feeling of comfort and sleep, 
there is often much distress and wakefulness. Increased 
temperature appears to hasten the normal changes tak 
ing place in the tissues; oxidation is more rapid; the 
tissues are more quickly exhausted, and the vitality is 
lowered. 
Winter and Summer. The moderate cold of winter im- 
parts a feeling of vigor and stimulates the whole system. 
The cool air excites a desire to run, and to exercise the 
whole body; this activity adds to the amount of heat 
necessary to resist the cold. Without exercise, the in- 
ternal heat must be preserved by additional clothing, or 
the depressing effects of cold will be experienced. Cold 
weather brings a good appetite; the extra amount of 230 
THE ESSENTIALS OF HEALTH. 
food is so much more fuel, contributing to the mainte- 
nance of the animal heat; thus we learn that a healthy 
body always demands more food during the winter than 
during the summer. Muscular activity, extra clothing, 
and more food enable the body to resist the cold and 
still maintain its average temperature. During the heat 
of summer less food is required and more liquids are 
used, the perspiration is increased, and the clothing is 
lighter, all of which tend to diminish the supply of heat 
and increase the means for its escape. 
The Effects of Alcohol on the Temperature. There is a 
general belief among a large class of people that alcohol 
warms the body; so they naturally conclude that it is 
one of the best remedies to take before beginning a long 
journey in the cold. If alcohol is able to raise the tem- 
perature of the body, it might often prove a most desir- 
able agent. But has it this power ? To fully answer 
the question it is necessary to understand both the 
primary and secondary effects of this poison. Under- 
standing these, the reader will be able to draw his own 
conclusions. 
One of the first effects of alcohol is to paralyze the 
nerves which terminate in the walls of the small blood 
vessels, and which control their size. As a result, the 
vessels distend and the whole system of capillaries be- 
comes filled with an extra supply of blood. The minute 
blood vessels of the skin become distended with this ex- 
tra supply. Now it must be remembered that the blood 
from the interior of the body is much warmer than that 
near the surface; therefore when an extra amount of 
warm blood flows to the surface, it makes the skin feel 
much warmer. As the outside of the body feels warmer, ANIMAL HEAT. 
231 
a person is led to believe that the warmth extends 
throughout the whole system. This is physiological, 
and just what we should expect. But we know that the 
blood is cooled in passing through the skin, therefore, if 
more than the usual amount of blood be sent to the sur- 
face, then an unusual amount of heat will be given off. 
As a result of this extra loss of heat, the blood returns 
to the interior of the body much lowered in temperature, 
and cooling all the tissues with which it comes in contact. 
The period during which the skin feels warmer is 
very brief, while the period of cold following it is of 
much longer duration. During the second period there 
is a rapid fall in the temperature. This is physiological 
also, and just what should be expected. In some of the 
lower animals the decline may be very great, reaching 
as many as five degrees in birds, and three degrees in 
dogs. In man the decline is often as great as two de- 
grees, in some cases even more. This period of decrease 
may pass off in a few hours, if the amount of alcohol 
taken be small; but if the poisoning be sufficient to 
cause prolonged sleep, several days may be required to 
bring the temperature up again to its normal degree. 
From these facts it appears that the brief period 
of apparent increase of heat is followed by a longer one 
during which the temperature of the body is actually re- 
duced. In this condition the body is less able to resist 
the cold, and so becomes especially liable to influenza, 
bronchitis, pneumonia, and allied affections; while re- 
covery from their attacks will be more tedious and 
doubtful. In other words the resisting power of the 
body against all invading diseases is greatly weakened 
by the use of alcoholic beverages. 232 
THE ESSENTIALS OF HEALTH. 
There is an abundance of testimony from men who 
have been exposed to extreme cold, to show that alcohol 
increases the suffering and danger of such exposure. 
Explorers in Arctic regions and travelers in cold coun- 
tries are perfectly agreed on this question. Their testi- 
mony is all to the effect that the use of alcohol in cold 
countries is extremely hazardous. The same principle 
applies to exposure to unusual cold in more temperate 
climates, and shows the fallacy of drinking alcoholic 
liquors to “ warm one up ” or to aid in keeping warm 
on a cold day. They only make exposure to cold more 
dangerous. The men who never use alcohol bear such 
exposures much better and do their work more easily 
than those who take it. 
QUESTIONS. 
1. Give some of the sources of animal heat. 
2. Where is found the warmest blood in the body? 
3. Which are the cold-blooded animals ? Name some. 
4. Which are the warm-blooded animals? 
5. In what parts bf the body is the temperature the highest? 
6. How does the blood tend to equalize the temperature? 
7. What is the temperature of the healthy adult body ? 
8. How much heat does the body produce in one hour? In 
thirty-six hours ? 
9. What two tissues principally regulate the temperature? 
10. Explain the part performed by the lungs 
11. How does the skin regulate the temperature ? ' 
12 Give some of the effects of lowering the temperature. 
13. This is similar to what normal process? 
14. Describe the effects from raising the temperature ? 
15. What is one of the first effects of alcohol on the blood vessels? 
16. What is the result of this first effect? 
17. Does alcohol aid in resisting cold? THE EFFECTS OF TOBACCO. 
233 
CHAPTER XXII. 
THE EFFECTS OF TOBACCO. 
We believe that the desire among boys to be men 
and to do manly things is so great that if they knew 
the dwarfing and stunting effects of tobacco, they would 
never indulge in its use. For this purpose, therefore, 
we are anxious that the exact truth be clearly stated. 
Our objections to the smoking of cigarettes, or to- 
bacco in any form, are as follows : — 
1. It Lessens the Natural Appetite for Food and In- 
jures Digestion. We have already discussed the growth 
of cells, and the important part they play in all the 
processes of life. These rapidly changing cells must be 
fed ; but if the appetite be poor and digestion bad, then 
surely cellular action must be greatly affected. Such 
proves to be the case, for the early use of tobacco often 
checks the growth of the body, so that it never reaches 
the height and full development it would have reached, 
had it not been so poisoned. 
2. It Seriously Affects the Nervous System. This is shown 
by its effects on the heart. The unsteady and rapid 
beat leads to dizziness and rush of blood to the head. 
The sleep is disturbed with distressing dreams, and the 
morning finds the body unrefreshed. The brain is 
checked in its development, and is unable at all times 
to do its best work. The testimony of many eminent 234 
THE ESSENTIALS OF HEALTH. 
medical men, together with the statements of public 
men of wide observation, show unquestionably that 
Tobacco impairs the Mental Powers. Could a more 
serious charge be brought against it ? The evidence is 
strong and unanswerable. Its moderate use by the 
young weakens the ability to think, while its immoderate 
use may eventually destroy the mind. 
3. It Leads to the Opium Habit. It is a startling fact 
that some of the brands of cigarettes have opium mixed 
with them. The amount is small, — the tobacco may be 
only moistened with some weak juice of the poppy; but 
the active principle of the opium is there, and it will 
surely perform its poisonous work. It is to be feared 
that if our young men continue the use of cigarettes 
we shall soon see, as a legitimate result, a large number 
of adults addicted to the opium habit. 
4. It Creates a Craving for Strong Drink. This is an- 
other legitimate result of smoking. It is a result which 
could have been foretold simply by physiological reason- 
ing. That smoking leads to drinking is no longer a 
theory, for the wisest observers have testified that such 
is the case. There are both primary and secondary 
reasons why this result follows. It follows as the pri- 
mary effect of tobacco on the mouth, throat, and stomach ; 
the mouth and throat are dry, and there is a peculiar 
sinking sensation at the stomach ; these often tempt the 
smoker to drink. It is also to be noted that the 
majority of those who use alcoholic drinks also use 
tobacco; therefore when a person accepts an invitation 
to smoke he is more likely to be thrown into company 
with those who drink. 
The secondary reason is that as tobacco weakens THE EFFECTS OF TOBACCO. 
235 
the mental faculties and lowers the moral tone, so it 
makes the temptation to drink more difficult to resist. 
Smokers yield more readily to an invitation to drink. 
They accept the “ treat ” to a cigar or a cigarette ; and 
later the acceptance of a “ treat ” to strong drink be- 
comes much easier. Tobacco manufacturers have lately 
declared that since the more stringent temperance laws 
of Canada have been enforced, there has been a vast re- 
duction in the amount of tobacco consumed. 
5. Cigarette Papers often contain Arsenic. The effects 
of such a drug on a healthy organism cannot be other- 
wise than injurious. 
6. It is a Eilthy and Offensive Habit. The laws of 
ordinary politeness are violated daily by those who use 
tobacco in any form. A noted French lady, when once 
asked if it would be offensive to her to have gentlemen 
smoke in her presence, curtly replied, “ No gentleman 
ever smokes in my presence.” The man who smokes 
becomes completely saturated with the strong odor. 
His clothing, his living room, and even his breath are 
charged with it. It is astonishing to see how the 
smoke of tobacco will nearly strangle the young lady as 
she sits beside her friend in the carriage, or as she walks 
by his side in the street, and yet she quietly submits to 
the impolite treatment. Travel where you will, on the 
road, in the railway car, on the sidewalk, in the street 
cars, in halls, everywhere, you can see the traces of this 
filthy and offensive habit. 
7. It is Expensive. The purchasing of tobacco requires 
money which might be otherwise spent for personal com- 
forts and pleasures, or for public and benevolent enter- 
prises. The trouble is that the young man does not 236 
THE ESSENTIALS OF HEALTH. 
realize what it is to spend five or ten cents each day. 
Such small sums, placed at compound interest, grow into 
large figures by the time old age is reached. It would be 
far better to invest these savings in books, newspapers, 
lectures, concerts, or traveling. 
8. It is Unlawful. The statesmen of our country are 
so fully impressed with the fact that the coming genera- 
tion is likely to be weak in body and mind unless the 
use of tobacco by the young be checked, that at this 
time in twenty-nine States there are stringent laws for- 
bidding the furnishing of cigarettes or tobacco in any 
form to minors under certain ages. There are also at 
this time in thirty-five States and in all the territories, 
laws requiring instruction to be given to all pupils in the 
public schools on the nature and effects of tobacco, as 
well as of alcoholic drinks and other narcotics. 
In New York and Connecticut, it is not only un- 
lawful to furnish tobacco to persons under sixteen 
years of age, but it is also unlawful for such persons 
to smoke or use tobacco in any public place. In 
Massachusetts and Indiana, a person can be fined for 
advising or persuading any one under sixteen years of 
age to smoke or chew tobacco. In the District of Col- 
umbia, 257 physicians, 524 officers and teachers of the 
public schools, all the trustees of the public schools, 
and 86 pastors of churches, petitioned the 51st Congress 
for the passage of a bill prohibiting the selling, giving, 
or furnishing tobacco in any form to persons under six- 
teen years of age. Individuals can now walk the streets 
of the Capital of the nation and not see a single news- 
boy or other young lad with a cigarette in his mouth. 
The simple fact that the representative men of a whole THE EFFECTS OF TOBACCO. 
237 
nation, in Congress assembled, should pass such a bill, 
shows in itself that a grave danger was discerned, and 
that the time had come for the remedy to be applied. 
9. It Lowers Scholarship. The minister of Public 
Instruction of Paris has forbidden the use of tobacco by 
students of the public schools. Tobacco is prohibited in 
the military and naval schools of the United States 
Government. 
Notice the following testimonies, which could be mul- 
tiplied many times: — 
“ In our thirty years experience in teaching more than 
fifty thousand young people we have found the effects of 
this narcotic to be premature age, shattered nerves, men- 
tal weakness, stunted growth, and general physical and 
moral degeneracy; and therefore we now decline to re- 
ceive into our institution any who use this noxious weed” 
Such is the statement of Henry C. and Sara A. Spen- 
cer, principal and vice-principal of the Spencerian Busi- 
ness College. 
Dr. Willard Parker says, “ Tobacco is ruinous in our 
schools and colleges, dwarfing body and mind.” 
The President of the Baltimore Academy of Medicine 
says, “ The effects of tobacco on school-boys are so 
marked as not to be open for discussion.” 
In an examination for admission to the Free College 
of New York, seventy-one per cent of the girls who 
applied were passed, but only forty-eight per cent of the 
boys. The report attributes the smaller per cent of the 
latter to the stupefying effects of tobacco. 
A graduating class in Yale College was divided into 
four parts according to scholarship,— the best scholars 
in the first division, and the poorest in the fourth. In 238 
THE ESSENTIALS OF HEALTH. 
the first division twenty-five per cent used tobacco; in 
the second, forty-eight per cent; in the third, seventy per 
cent; and in the fourth, eiglity-five per cent. 
Dr. J. W. Seaver, of Yale College, has made some in- 
teresting observations on this subject. He says no young 
man can use tobacco without injuring himself seriously. 
Of the junior students who received the highest appoint- 
ments, ninety-five per cent did not use tobacco; of those 
who received the next highest appointments, eighty-seven 
and one half per cent did not use it; while of all who 
received appointments of some kind, eighty-four and 
three-tenths per cent did not use tobacco. The per cent 
of non-users among those who received no honors what- 
ever was much less. In other words, the highest honors 
of a class are almost exclusively carried off by those who 
do not use tobacco; while those who remain lowest in 
scholarship are almost invariably addicted to the habit. 
This is in accord with the testimony of a large number 
of teachers of wide experience, who positively assert that 
the pupils who use tobacco are not found at or near the 
head of the class. Tobacco and scholarship are no 
friends. They cannot go together. 
The President of Union College says, “ The use of 
this poisonous narcotic, next to intoxicating liquor, is 
more destructive to the health of our youth than any 
other agent.’.’ 
The Emperor Louis Napoleon, in 1862, issued an 
edict forbidding the use of tobacco in all the national 
institutions, because he was satisfied from investigation 
in the schools and colleges that the average standing in 
both scholarship and character was lower among those 
who used tobacco than among those who did not. THE EFFECTS OF TOBACCO. 
239 
10. It Lowers the Moral Tone. This is most marked in 
the deceit practised by boys in their efforts to conceal 
the fact of their using tobacco from their parents. They 
will positively deny its use, and resort to all manner of 
deception to account for the unmistakable odor. Boys 
who would not be guilty of telling a falsehood on other 
matters soon find it easy to lie about this habit. They 
hide their cigarettes ; they go away from home to smoke 
them ; and in all their manners show that they are in 
a bad business. What result can follow such falsifying 
and deception other than a lowering of the moral tone ? 
The ten charges thus brought against tobacco are of 
such a character that there is but one conclusion to the 
matter. It is this : The use of tobacco greatly endan- 
gers and impedes health, happiness, and prosperity. 
QUESTIONS. 
1. How does tobacco affect the appetite and digestion ? 
2. How does it affect the heart ? The mental powers ? 
3. Is there danger it may lead to the opium habit ? Why ? 
4. Give a primary reason why smoking leads to drinking. 
5. Give a secondary reason why this is true. 
6. What poison is sometimes found in cigarette papers? 
7. Are politeness and neatness aided by the tobacco habit? 
8. Is it an expensive habit? 
9. What is said about its being unlawful ? 
10. Is tobacco an aid to scholarship ? 
11. What proof have we that it affects the morals? 240 
THE ESSENTIALS OF HEALTH. 
CHAPTER XXIII. 
WHAT TOBACCO COSTS: IN BODY; IN 
MIND; IN MORALS; AND 
IN MONEY. 
What it Costs the Body. It is not natural for man to 
smoke. There is not an animal in a state of nature 
that uses tobacco in any form, unless exceptions are 
made in favor of the tobacco-worm, living on the green 
leaves of the plant, and a species of wild goat found in 
Africa. That it is not natural for man is evident from 
the shock to the system which follows its first use, 
resulting in nausea, vomiting, and great depression. 
Upon experiencing these symptoms the first Napoleon 
exclaimed, “ Oh, the swine ! my stomach turns ! ” Man 
is the only animal using this vegetable. How different, 
in this respect, is tobacco from other vegetables. If 
we eat half of a potato, apple, carrot, beet, or any other 
vegetable, raw or cooked, and then throw away the 
other half, how eager are many of the lower animals for 
it! If the horse and dog do not care for it, then hosts 
of ants and flies claim it as their own. But not so with 
the half-smoked cigar, carelessly thrown to the ground. 
The horse, dog, ants, flies, even all forms of animal life 
below man shun it, and there it remains where thrown, 
until the street-sweeper or the storms have removed it. 
Man alone appears to care for it. Tobacco is a disease- WHAT TOBACCO COSTS. 
241 
producing instead of a disease-curing plant. In the 
preceding chapters attention has been called to the ill 
effect of this drug on the growing body. It has been 
shown that its effects on the appetite and digestion 
result in checking the growth and in producing a poorly 
developed organism. Chronic sore throat, with its 
accompanying deafness, are often a part of the smok- 
er’s complaints. The palpitation of the heart, the trem- 
bling of the hands, and the excessive nervousness all 
testify that tobacco is used at an immense waste of vital 
energy. 
But let us listen to the teachings of some of our emi- 
nent writers on this subject. Below are given a few ex- 
tracts, a number of which were taken from the writings 
of “ Meta Lander,” — Mrs. Margaret Woods Lawrence, 
of Baltimore, — entitled “ The Tobacco Problem.” The 
gifted author has collected a vast amount of material 
bearing on this important subject. The quotations 
represent the convictions of men of high standing and 
acknowledged ability. 
Hr. Ferguson : “ I believe that no one who smokes 
tobacco before the bodily powers are developed ever 
makes a strong vigorous man.” 
Many leading physicians of Philadelphia: “ Cigarette 
smoking is one of the vilest and most destructive evils 
that ever befell the youth of any country ; its direct 
tendency is to a deterioration of the race/"’ 
Prof. H. H. Seerley : “ Boys that begin the habit at 
an early age are stunted physically, and never arrive at 
normal bodily development.” 
Horace Greeley: “ Show me a drunkard that does not 
use tobacco, and 1 will show you a white blackbird.” 242 
THE ESSENTIALS OF HEALTH. 
Medical Director U. S. Navy: “ The future health 
and usefulness of the lads in our naval schools require 
the absolute interdiction of tobacco in any form.” 
Dr. Copland, F. R. S.: “ Tobacco creates a thirst, to re- 
move which alcoholic stimulants are often resorted io.” 
Dr. Cowan: “ The exceptions are very rare when a 
user of tobacco in any of its forms is not ultimately led 
to use alcoholic liquors.” 
Gladstone “ detests smoking.” Haeckel: “ I have never 
smoked.” Ruskin “ abhors the practice of smoking.” 
Charles Reade : “ I have seen many people the worse 
for it, and never saw anybody perceptibly the better 
for it.” 
Dr. Willard Parker: “ Tobacco is doing more harm 
in the world than rum. It is destroying our race.” 
Medical Examiner U. S. Navy : “ One out of every 
one hundred applicants for enlistment is rejected be- 
cause of irritable heart, arising from tobacco poisoning.” 
Dr. Bowditch : “ A man with a tobacco heart is as 
badly off as a drunkard.” 
The famous marksman, Carver: “ I have never tasted 
intoxicating drinks, nor do I use tobacco in any form.” 
The winner of the international boat race, Han- 
lan: “ The best physical performances can only be 
secured through absolute abstinence from alcohol and 
tobacco.” 
Supt. of N. Y. Insane Asylum : “ Tobacco has done 
more to cause insanity than spirituous liquors.” 
Supt. Insane Asylum at Worcester, Mass.: “That 
tobacco produces insanity, I am fully convinced.” 
In four insane asylums there were 294 cases of “in- 
sanity from the use of alcohol.” Of these 294, it was WHAT TOBACCO COSTS. 
243 
ascertained that 206 were led to intemperance by the 
use of tobacco. 
The German Government has ordered the police to 
forbid boys under sixteen years of age smoking in the 
streets, because of its evil effects on mind and body. 
These facts are sufficient to warrant us in stating that 
tobacco costs the body its best development and its per- 
fect health. 
What it Costs the Mind. Reference has already been 
made, in the preceding chapter, to the effects of tobacco 
on the general scholarship. Some further testimony on 
this point may serve to more forcibly present the truth. 
In Paris “ it is shown that smokers have proved 
themselves, in the various competitive examinations, far 
inferior to others.” 
Dr. Constan, of Paris, concludes a long article as fol- 
lows : “Theinfluence of tobacco clogs all the intellectual 
faculties, and especially the memory; and the injury is 
greater in proportion to the youth of the individual.” 
Ex-Senator Doolittle: “ I believe that the mental 
force, the power of labor and endurance of our pro- 
fession, is decreased at least twenty-five per cent by the 
use of tobacco.” 
Professor Lizars, of Edinburgh : “ It is painful to 
contemplate how many promising youths must be en- 
feebled in their minds and bodies, before they arrive at 
manhood, by the use of tobacco.” 
With these facts before us, it is safe to assert that 
tobacco costs the mind its highest development and its 
most brilliant achievements. 
What it Costs the Morals. The use of tobacco is an 
illustration of the most supreme selfishness. One per- 244 
THE ESSENTIALS OF HEALTH. 
son only enjoys it, and even that enjoyment is usually 
at the expense of those about him. The breath, the 
clothing, the air around the smoker, all are saturated 
with the tobacco-poison. The fact that generous and 
kind men will continue in such a purely selfish practice 
is simply an illustration of the truth that the drug has 
so affected their sense of propriety as to render them 
unaware of their true position. If men must smoke 
they should confine their operations to their own private 
quarters, where as few as possible must suffer, rather 
than be continually puffing their cigars in the faces of 
enduring women and inoffensive children. 
Upon entering depots, halls, and other public places, 
we are often greeted with the sign, “ No Smoking.” It 
seems to be absolutely necessary to give stern commands 
to men not to smoke in these places where women and 
children gather. Yet why do we not see commands 
like these ? “ Do not crowd the children.” “ Do not 
thrust the sick out into the cold.” In other words, 
were it not for the effects of tobacco on the moral sense, 
blunting its keener qualities, there would be no need of 
asking men not to smoke in any place where the rights 
of others to the free, pure air are universal. 
We positively declare that a man has no more right to 
put tobacco smoke into the air which we are about to take 
into our system, than he has to put some disagreeable 
drug into the water which we are just about to drink. 
Pure air is one of our inherited gifts, and he who wil- 
fully poisons it, or makes it disagreeable for his fellow 
beings, is guilty of no small breach of common civility. 
On the morals of the youth, tobacco has a most 
marked effect. It is probable that the indifference of WHAT TOBACCO COSTS. 
245 
the adult smoker is largely due to the early use of the 
cigar or cigarette, as during the early years of life all 
the faculties are so much more easily affected. Deceit 
seems to be a boon companion of the boy and his ciga- 
rette. To have the morals of our young men reach 
their highest attainments, the cigarette should be ban- 
ished from our midst. What do some of our writers 
and public men say on this subject? 
Jackson Jarves says, “ Whatever the benefit or harm 
the use of tobacco may do the consumer’s body, its com- 
mon tendency is to render the mind indifferent to the 
well-being of his neighbors.” 
Dr. Parker: “ Tobacco demoralizes. It makes a man 
careless about his hair; he lets his nails go unclean; 
his clothes are soiled, and he is generally untidy.” 
Professor Stuart, of Andover : “ It creates a nervous 
irritability, and thus operates on the temper and moral 
character of men.” 
Professor Mead, of Oberlin: “ The tobacco habit 
tends to deaden the sense of honor; and none are more 
likely to practise deception unscrupulously than those 
who use the weed.” 
The President of Wisconsin State University : “There 
are few spectacles giving a more disgraceful impression 
of our civilization than that of a lad sporting a cigar or 
cigarette, in imitation of the bad habits of those older 
in years than himself.” 
Superintendent of the Reform School, at Westboro’, 
Mass.: “ All boys sent here have been the users of 
tobacco.” 
Chancellor Sims, of Syracuse University : “ The to- 
bacco-habit is deteriorating to the one indulging in it.” 246 
TIIE ESSENTIALS OF HEALTH. 
Dr. Harris : “ There is not another article of luxury 
that so secretly and yet so surely saps all the founda- 
tions of manliness and virtue.” 
From these statements we can but draw the con- 
clusion that he who indulges in tobacco runs the risk 
of having the highest and best attributes of his nature 
brought under its benumbing power.” 
What it Costs in Money. The financial view of the 
tobacco problem merits careful attention, not only be- 
cause the money expended for the cigars or cigarettes 
might be better used in the purchase of books, but also 
because habits of thrift and economy formed in the 
young make no small part of a man’s future success. 
Such habits do more than make a saving of money; 
they teach that time itself is precious, and that rapidly 
passing hours can never be recalled. The normal phys- 
iological man is economical of his money, his time, 
his mental powers, and of all his endowment. He is 
temperate in all things. He should have immense re- 
serve forces which he draws upon only at times of great 
peril and need. 
Later in school life our readers may find themselves 
hard at work over some of the great questions of polit- 
ical economy. In fact, even now they are aware there 
is much unrest in the land over the question of capital 
and labor. A small number of people are becoming 
richer and richer, and controlling great interests and 
thousands of men, while a large number of people work 
very hard, year after year, and yet do not enjoy the 
ordinary comforts of life, to say nothing of owning a 
home of their own. Often it is true that sickness and 
misfortune keep the most economical persons from WHAT TOBACCO COSTS. 
247 
laying aside any part of their hard-earned wages. But 
we desire to show, not only that the use of tobacco 
injures the consumer, but also that the money thus 
wasted might bring many additional comforts to him 
and to his friends, thus contributing much toward the 
general prosperity of the country. True patriotism, 
therefore, demands that boys should not use tobacco. 
A few lines will show how expensive is the tobacco- 
habit, and how important a part it plays in preventing 
many of our hard-working people from enjoying more 
of the comforts and pleasures of life. 
The secret of the trouble lies in the fact that we fail 
to realize how soon cents makes dimes, and dimes 
make dollars. Remember that, even at the rate of six 
per cent compound interest, money will double itself in 
twelve years, while if the rate be ten per cent, money 
will double in seven years. This doubling of money, 
without any apparent effort on our part, is one of the 
surprising things of finance. Let us illustrate this 
principle. 
Suppose a boy should begin the use of tobacco at ten 
years of age, and suppose he purchases only one cent’s 
worth of tobacco each day, until he is forty years of 
age; now had he received seven per cent compound 
interest for the money thus expended, how much would 
his tobacco bill represent ? $350. Neither boys nor 
men, though, stop at a cent’s worth of tobacco a day. 
Suppose he used only five cents a day for his tobacco 
during all these years, still this, at the above rate of in- 
terest, would amount to over $1700; surely a good pres- 
ent to receive on your fortieth birthday! But suppose 
the young man is now twenty-five years of age and just 248 
THE ESSENTIALS OF HEALTH. 
starting out in business for himself. He buys five or six 
good cigars each day and they cost him fifty cents. This 
amount regularly placed at seven per cent compound in- 
terest for thirty years would make his tobacco bill repre- 
sent over $17,000. A man spends a dollar a day for 
tobacco. How much would his tobacco bill represent 
in only ten years, at seven per cent compound interest ? 
over $5,000. In twenty years ? over $16,000. 
We have a very interesting letter on this subject, from 
Luther Prescott Hubbard of New York. Mr. Hubbard 
has been Secretary of the New England Society for 
nearly forty years, and for nearly sixty years has been the 
financial agent of the American Seamen’s Friend Society. 
His connection with literary and financial enterprises 
entitles his statements to great weight. Mr. Hubbard 
began to chew tobacco at the age of twelve, and a few 
years later commenced smoking. He says his tobacco 
cost him, on the average, thirty-seven and a half cents 
each day. We will let him tell the rest in his own 
language which he kindly allows us to use : — 
“I now deposited the money I had been so long squan- 
dering for tobacco in the Seamen’s Bank for Savings. I will 
tell the boys what I did with it, that they may see how un- 
wise and inexpedient it is to commence the expensive, de- 
moralizing habit of smoking or chewing tobacco. 
“We had long lived in the city, but the annual visits of 
the children to their grandfather’s made them long for 
a home among the green fields. I found a very pleasant 
place for sale. There were over two acres of land, with 
abundant shade and fruit trees, a good garden, a fine view 
of Long Island Sound, — near the academy, churches and 
schools, and a convenient distance from New York. The WHAT TOBACCO COSTS. 
249 
cigar money was drawn upon to purchase the place, and it 
is mine. 
“ My smoking was moderate compared with that of many, 
costing me only thirty-seven and a half cents a day, equal 
to $> 136.50 per annum, which, at seven per cent interest for 
fifty-nine years, amounts to the small fortune of $103,626.32. 
This has afforded means for the education of my children, 
with an appropriate allowance for benevolent objects. 
“ Great as this saving has been, it is not to be compared 
with improved health, a clear head and steady hand, at the 
age of over eighty-three years, and entire freedom from de- 
sire for tobacco in any form.” 
There are other practical questions that should make 
every intelligent schoolboy appreciate the money part 
of this evil. If a boy saves fifteen cents each day while 
going through his four years’ course in the high school, 
how much money will he have ? Suppose this money 
had been invested in books, and suppose that he had 
purchased twenty-five volumes of the most recent works 
at an average price of two dollars each, and fifty vol- 
umes at one dollar each ; in addition to these how many 
volumes of the standard works of such writers as Scott 
and Dickens, Gibbons and Macaulay could he purchase 
at thirty-five cents each ? “A good sized library,” you 
will say, when you figure the result. Too choice a 
collection to be burned up at the rate of fifteen cents a 
day. 
Only one verdict can be given on this subject. It is 
that, after the most careful examination of the whole 
tobacco question, not a single fact can be brought for- 
ward in its favor. 250 
THE ESSENTIALS OF HEALTH. 
CHAPTER XXIV. 
OPIUM. — CHLORAL. 
The Opium Habit. In this country the opium habit is 
usually formed as a result of taking the drug for the re- 
lief of pain. If the pain returns, another dose is taken. 
Sometimes the disease is of such a character that the 
pain continues for many weeks, necessitating the con- 
tinued use of the opium. After a time, however, the 
original disease may entirely disappear, yet the sufferer 
finds he must continue the opium, or endure great agony 
of body and mind. Knowing how easily the opium habit is 
contracted, the careful physician does not prescribe it for 
those conditions where its use is likely to be necessary 
for some weeks. He substitutes less powerful narcotics, 
and allows his patients to suffer some pain, rather than 
run the fearful risk of producing such a terrible habit. 
Effects of Opium. Opium is a powerful drug. Even a 
single dose prescribed by a physician for the relief of 
some severe and sudden pain is often followed by unde- 
sirable effects. But when repeatedly taken for a long 
time, the body becomes thin, and the skin grows sallow 
and parchment-like. The opium eater suffers from loss 
of appetite and improper action of all the organs of the 
body. There is a marked lowering of the will-power, 
and loss of memory. The person will not hesitate to 
deceive and lie about the habit. He loses all sense of 
truth, and appears to forget there is any difference be- OPIUM. —CHLORAL. 
251 
tween right and wrong. When unable to obtain the 
drug, the victim suffers the most excruciating physical 
and mental torments. 
Preparation of Opium, or Patent Medicines. It is a well- 
known fact that nearly all physicians are opposed to 
so-called patent medicines. The chief reason for this 
is that, as they are ignorant of the composition of the 
medicine they are unable to pass judgment upon its 
merits and demerits. When a person is ill the physi- 
cian prescribes those drugs which will have certain 
desired effects in that particular case. It may be an 
acute cold, and the very next patient he visits may also 
be suffering from the same affection ; yet entirely dif- 
ferent drugs may be prescribed in the second case. But 
a patent medicine makes it necessary that persons of 
different constitutions, living in various climates, at all 
seasons of the year, and in varying degrees of health, 
or in a wmrd, that all classes and conditions of people 
everywhere must take the one unvarying mixture. No 
one man can intelligently prescribe a single mixture 
which will be applicable to thousands of cases ; it is as 
impossible as it is unscientific. 
A large number of the popular “ soothing syrups ” of 
the present day contain opium. These syrups are freely 
given to children to produce sleep, or to correct some dis- 
turbance of the digestive organs. They are directly re- 
sponsible for many deaths. Nothing of the kind should 
ever be given. Let all such cases be referred to a phy- 
sician. Is it not more probable that your own local physi- 
cian should know better what is needed in case you are 
ill than a man, uneducated in medicine, living thousands 
of miles away ? The “ tonics,” “ bitters ” and “ soothing THE ESSENTIALS OF HEALTH. 
252 
syrups ” of the market are too likely to contain either 
alcohol or opium to make them safe remedies. 
Chloral. A few years ago this drug was extensively 
prescribed by medical men because it was capable of 
producing sleep, relieving pain, and appeared to be free 
from danger. After some experience with it, the dis- 
covery was made that it was far from being free from 
danger. A number of deaths were reported from its 
use, and many persons became addicted to the chloral 
habit. Of late it is not used so extensively, yet there 
is danger that it may be taken repeatedly as a sub- 
stitute for opium. The habit is easily acquired and as 
difficult to break as that of taking opium. 
After a short use of chloral the tongue becomes coated, 
the digestion impaired, and the stomach unable to retain 
the food. There is oppression and pain in the stomach, 
associated with nausea and vomiting. The nervous sys- 
tem soon breaks down under the constant use of the 
drug; the person becomes irritable, the muscles tremu- 
lous, and the heart irregular in its beat. It soon becomes 
impossible to procure sleep without large doses of the 
drug; while it not infrequently occurs that too large 
doses are taken, with fatal results. 
Tea and Coffee. The active, growing body finds in 
these substances.nothing which it needs. Tea and coffee 
are especially bad for those who have nervous temper- 
aments, and those who lead indolent lives. They inter- 
fere with digestion, and often produce biliousness and 
wakefulness. The student can accomplish more and 
better work without these drinks than with them. THE NERVOUS SYSTEM. 
253 
CHAPTER XXV. 
THE ANATOMY OF THE NERVOUS 
SYSTEM. 
Two Systems. The nervous system of man and all 
vertebrate animals may be divided into two secondary 
systems; each having its own particular set of nerves 
and nerve centers. These are called the cerebro-spinal 
system, and the sympathetic, or ganglionic, system. 
The Cerebro-Spinal System. The cerebro-spinal system 
is composed of the brain, the spinal cord, and the nerves 
which originate from them. The brain and the spinal 
cord are the great nerve centers of the body. They are 
connected with the nerves of the special senses, and 
with the nerves of common sensation; they convey to 
the mind the sensations of taste, touch, sight, smell, and 
hearing, as well as the sensations of pain, hunger, thirst, 
etc. The mind, in turn, is capable of expressing itself 
through them. Through the cerebro-spinal system the 
commands of the mind are conveyed to various parts 
of the body; thus, we “ will ” to move a muscle; in- 
stantly a force is sent along the nerves of this system 
to the proper muscle, and it promptly obeys. 
The Sympathetic System. The sympathetic, or gan- 
glionic, system consists of a number of ganglia and nerve 
fibers. The ganglia are collections of nerve cells. They 
may be very small, composed of only a few cells, and 254 
TIIE ESSENTIALS OF HEALTH. 
visible only with the microscope ; or there may be such 
a collection of nerve cells that the ganglia have consid- 
erable size. The sympathetic 
system consists of two rows of 
these ganglia, one row on either 
side of the spinal column. It 
consist also of nerves which pro- 
ceed from the ganglia to the 
organs in the thoracic, the ab- 
dominal, and the pelvic cavities. 
The sympathetic nerves do not 
go to the skin, neither are they 
connected with the special 
senses, nor are they under the 
control of the will. This system 
presides over the involuntary 
processes of the body ; as the 
circulation, the digestion, the 
respiration, the absorption, the 
nutrition, and the involuntary 
muscles. It also controls the 
secretions of glands, and has 
much to do with the amount of 
blood distributed to the various 
organs and tissues. 
The ganglia are connected 
with each other by small nerve 
fibers, while other minute fibers 
connect the ganglia with the 
cerebro-spinal system. Thus one organ is made to act 
in “ sympathy ” with another, so that if one part suffers 
in any way another suffers with it. 
Fig. 89. Diagram of the 
cerebro-spinal system : c, cer- 
ebrum ; cl, cerebellum; s, 
spinal column ; N, nerves for 
the upper and lower limbs ; 
n, nerves going to the mus- 
cles and the skin. THE NERVOUS SYSTEM. 
255 
Nerve Tissue. There are two kinds of nerve tissue; 
one is composed of nerve fibers, and the other of nerve 
cells. The presence of numbers of the nerve cells gives 
a gray color to the tissue, while the nerve fibers appear 
white. Hence an accumulation of nerve cells is called 
the gray substance, and a collection of nerve fibers is 
called the white substance. The nerve cells represent 
the centers of activity from which the orders are issued. 
The nerve fibers are simply the conductors, conveying 
the messages from place to place. The gray substance 
therefore, represents the seat, or origin, of the mysteri- 
ous forces of the nervous system; while the white 
substance represents only so many fibers for the trans- 
mission of the forces. 
Fig. 90. Various forms of nerve cells, highly magnified. 
The Nerve Cells. A collection of nerve cells always 
makes a nerve center. The greatest collection of cells 
is found in the gray matter of the brain, the next in the 
spinal cord, and the next in the ganglia of the sympa- 256 
THE ESSENTIALS OF HEALTH. 
thetic system. Nerve cells generate nerve force. They 
also receive it from other cells and give it out again. 
They are therefore generators and transmitters of nerve 
force. 
The cells vary exceedingly in size and shape. Some 
are of a circular form, as at the upper left corner of 
Fig. 90. Others have a long process extending from 
them, as shown in the cell to the right of the last. This 
one process represents the beginning of a nerve fiber, 
so that nerve force originating in the cell can be con- 
veyed from it through this fiber to some distant organ 
or tissue. Other cells have many processes, one of 
which conveys nerve force to the distant parts. 
The Nerve Fibers. The nerve fibers convey the nerve 
force from one part of the body to another. If an im- 
pression is made on the ends of some of the fibers they 
will convey it to the nerve cells at their origin : thus if 
the skin be touched, an impression is made on the ends 
of nerve fibers which is instantly conveyed to the spinal 
cord, and then to the brain, where a sensation is pro- 
duced corresponding to that on the skin. No change 
occurs in the nerve fiber during the passage of this 
nerve force, so far as we know, any more than a change 
is produced in a wire by sending over it a telegraphic 
message. We know that if the wire be cut the mes- 
sage will be interrupted; so if a nerve fiber be cut in 
any part of its course all communication is at once shut 
off. 
Two Kinds of Nerve Fibers. The nerve fibers of the 
cerebro-spinal system are peculiar in this respect; they 
can convey a message only in one direction. A mes- 
sage may be sent in either direction over a telephone THE NERVOUS SYSTEM. 
257 
or over a telegraph wire ; two wires are not necessary ; 
but with the nerve fibers, two complete sets are re- 
quired. One set conveys sensation from the outer parts 
toward the nerve centers; while the other set conveys 
impressions from the nerve centers outward to the 
muscles. The first set is composed of nerve fibers 
called sensory fibers, because they convey sensations to 
the spinal cord and brain: the other set consists of 
fibers called motory fibers, because they convey the 
stimulus of motion from the brain and spinal cord to 
the muscles. So far as is known there is no difference 
in the structure of these fibers, and as a rule they are 
side by side throughout the body. 
A nerve, as seen in the body, and as mentioned in the 
books, consists of a large number of these nerve fibers 
held together by a delicate connective tissue. Each 
nerve fiber extends the whole length of the nerve, from 
its beginning in the brain or spinal cord to its 
termination. 
The Brain. The brain is well protected in the cranial 
cavity. It is surrounded by three distinct membranes, 
of which the middle one is capable of secreting a fluid. 
The membranes protect the brain from friction against 
the bony walls, while the watery secretion gives it some 
freedom of motion. The brain is well supplied with 
blood vessels, — large arteries entering the base of the 
skull with the spinal cord. 
The weight of the brain depends partly upon the size 
of the individual, and partly upon his intellectual capa- 
city. The average weight of the brain of an adult male 
is a trifle over three pounds, 494 or 49f ounces. The 
brain of Cuvier, the naturalist, weighed over 64 ounces, 258 
THE ESSENTIALS OF HEALTH. 
and the brain of Daniel Webster weighed 63 J ounces. 
The brains of idiots are very light, weighing from 27 
ounces to as low as 8 ounces. 
Fig. 91. Side view of the whole human brain: (1) cerebrum; (2) cere- 
bellum ; (3) medulla. 
While it is true that many noted men had large brains, 
it is also true that some equally as noted had small 
brains. Yet it can be safely asserted that, as a general 
rule, the larger the brain the greater the capacity for 
intellectual power; but to this statement there are some 
striking exceptions. It appears that there is something 
besides quantity necessary for the highest mental capa- 
bilities. This may be called quality, or some peculiarity 
of the brain material whereby it renders its possessor 
capable of great intellectual attainment. 
The brain is divided into the cerebrum, the cerebel- 
lum, and the medulla oblongata. 
The Cerebrum. The cerebrum is the brain proper. It THE NERVOUS SYSTEM. 
259 
is the part above the ears, and is familiarly known as 
the great brain. It is believed that the cerebrum is the 
organ of the mind; that it is here we think, know, and 
reason. The cerebrum is divided into two parts by a 
Fig. 92. The human brain, viewed from above : only the cerebrum is 
seen, with its deep fissure nearly dividing it. 
natural fissure which passes from the front backward. 
At the bottom of the fissure the two parts are united by 
a hand of nervous tissue, as shown at 3 in Fig. 93. 
From this it would at first appear that we have two 260 
THE ESSENTIALS OF HEALTH. 
brains corresponding to the right and left sides of the 
body; but doubtless the band of union between them 
not only connects the structure of the two but also in 
some way unites their functions. Figs. 91, 92, and 93 
show that the surface of the brain is not smooth in 
Fig. 93. One half of the brain,—the inner surface: (1) the cere- 
brum; (2) the cerebellum ; (3) the band of tissue that unites the two 
sides of the brain ; (4) the medulla ; (5) the spinal cord. 
man, but is thrown into a number of ridges or convo- 
lutions. The number of convolutions and the depth to 
which they reach vary in the different animals. In some, 
the surface is perfectly smooth, as in the pigeon and frog; 
in others, the convolutions are shallow and few in num- 
ber ; but in man, they are many and very deep. As a rule, THE NERVOUS SYSTEM. 
261 
the more intelligent the animal so much the more numer- 
ous and so much the deeper will be the convolutions of 
the cerebrum. The reason 
for this is readily under- 
stood when the structure 
of the brain is made clear. 
Gray and White Matter of 
the Cerebrum. The gray 
matter is on the outside of 
the brain : the white mat- 
ter is within, forming the 
center of the brain. The 
white matter is raised in 
slight folds on its surface 
to form the center of the 
convolutions ; but the bulk 
of the convolutions is 
formed by the gray matter. It has been stated that 
the gray matter consists principally of nerve cells, and 
that these cells are the active agents in originating, 
Fig. 94. (1) the brain of a pigeon ; 
(2) the brain of a frog,— both viewed 
from above. There are no convolu- 
tions on the cerebrum, H. 
Fig. 95. A diagram illustrating that the convolutions of the brain 
give more surface for the gray matter. 
receiving, and sending forth orders. The cells com- 
mand and the fibers obey; the cells originate, and the 
fibers carry the messages. If the cells are specially con- 
cerned in originating and commanding, it is evident that 
a large amount of the gray matter is most desirable. 262 
THE ESSENTIALS OF HEALTH. 
The convolutions provide for this extra amount of gray 
matter. This is made clear by the accompanying dia- 
gram. Suppose the surface of the brain be smooth, and 
covered with a layer of gray matter, then the line from 
A to B would represent the extent of the surface. But 
suppose the layer of gray matter be thrown into folds, 
or convolutions, then the amount of surface would be 
represented by the line 1 to 2. It is at once clear that 
the line 1 2 is much longer than the line A B. In 
other words, the convolutions greatly increase the 
amount of gray matter. It follows, therefore, that the 
deeper the convolutions and the greater their number, 
so much the more will the gray matter be in excess. 
This anatomical fact probably explains why some 
smaller brains are more intellectual than others which 
exceed them in size. In the former cases it is probable 
that the convolutions are deeper and more numerous 
than they are in the latter; thus actually giving more 
gray matter in the smaller brain. 
The Cerebellum. This part of the brain is situated be- 
neath the back part of the cerebrum, and is often called 
the lesser brain. It consists of gray and white matter 
arranged in the form of parallel ridges and furrows run- 
ning over its surface, as represented in Fig. 91. 
The Medulla Oblongata. The medulla, as it is gen- 
erally called, is situated at the upper end of the spinal 
cord, between the cord and the brain. It represents an 
enlargement of the upper part of the spinal cord, as illus- 
trated at 4, Fig. 93. It is well protected in the thick 
bones at the base of the skull. The functions of the 
medulla are so necessary to life that it must be regarded 
as the most vital portion of the entire body, yet it is 
only about one and one fourth inches in length. THE NERVOUS SYSTEM. 
263 
The Spinal Cord. The spinal cord, as illustrated in 
Fig. 89, represents the elongated part of the cerebro- 
spinal system. It is about eighteen inches in length, 
one half an inch in thick- 
ness, and is nearly circular 
in shape. It is surrounded 
by three membranes which 
are continuations of those 
surrounding the brain, and 
is well protected in the spi- 
nal canal of the vertebral 
column. It begins at the 
medulla, and terminates at 
the lower end of the spinal 
column in a number of line 
threads, as illustrated in 
Fig. 89. It is, like the 
brain, divided into halves 
by deep fissures. One fis- 
sure extends down the an- 
terior, and the other down 
the posterior median lines, 
nearly dividing the cord 
into two parts. Fig. 96 
illustrates these fissures; 
one, the anterior, showing 
more clearly than the 
other. An open central canal is also seen. From the 
sides of the spinal cord there are given off thirty-one 
nerves, known as the spinal nerves. 
Fig. 96. Cross sections of the 
spinal cords of different animals, 
represented as twice the natural 
size; (1) horse; (2) ox; (3) man; 
(4) hog; (5) squirrel. 
White and Gray Matter of the Spinal Cord. The gray 
matter of the cord is in the center. It is so arranged 264 
THE ESSENTIALS OF HEALTH. 
that when the cord is cut transversely it slightly re- 
sembles the letter H. The darkly shaded portions in 
Fig. 96 illustrate this fact, and it is also shown in Fig. 
97. In the upper, or anterior points of the letter H, in 
Fig 97, are seen some irregular-shaped, darkly shaded 
bodies; these are the large nerve cells, a representation 
of which is given in Fig. 90. 
Fig. 97. A cross section of the spinal cord, magnified. 
Outside the central gray matter is the white matter, 
which is composed of fibers. The fibers extend up and 
down the cord, so that a transverse section of the cord, 
as seen in Fig. 97, shows the fibers to be circular and 
white, with a dot or dark spot in the center. This dark 
spot represents a cross section of that part of a nerve 
fiber which transmits the nerve force; the white sub- 
stance around it is for insulation and protection. These 
fibers finally enter the brain and are distributed to all 
parts of it, being at last connected with the nerve cells. 
The Spinal Nerves. Each one of the spinal nerves orig- 
inates in the spinal cord by two roots. One root, the an- THE NERVOUS SYSTEM. 
265 
terior, originates from the anterior part of the gray 
matter, as illustrated at 1, Fig. 98. The other origi- 
nates from the posterior part, as shown at 2. Both these 
roots unite to form one nerve, at 3. On the posterior 
Fig. 98. A diagram illustrating the origin of the spinal nerves from 
the spinal cord- (3) is a spinal nerve; (1) and (2) are the roots, which 
originate from the gray matter of the cord; G, a collection of nerve cells; 
(1) the motory root; (2) the sensory root. 
root is a ganglion, G, or a collection of nerve cells. 
The nerve fibers, at 3, continue together as a spinal 
nerve until they reach the distant parts of the body, 
when they separate again. Those fibers which origi- 
nated from the anterior part, known as motory fibers, 
terminate in muscles; while those from the posterior 
part, known as sensory fibers, terminate in the skin. 
QUESTIONS. 
1. Name the two nervous systems. 
2. What composes the cerebro-spinal system ? 
3. What composes the sympathetic system ? What are ganglia? 266 
THE ESSENTIALS OF HEALTH. 
4. What does the sympathetic system preside over and control? 
5. Give the two kinds of nerve tissue. 
6. How do they differ in color ? 
7. What do the nerve cells represent? The nerve fibers? 
8. What makes a nerve center ? 
9. What do nerve cells generate, receive, and impart ? 
10. How many varieties of nerve fibers ? 
11. Describe the function of the sensory fibers. The motory 
fibers. 
12. What is a nerve? 
13. How many membranes surround the brain. 
14. Of what use are they ? 
15. Give the average weight of the brain of an adult. 
16. Does a small brain necessarily indicate low intelligence? 
17. Give a general rule about this. Any exceptions ? 
18. Into how many parts is the brain divided? 
19. What is the name of the brain proper? 
20. What is the function of the cerebrum ? 
21. How is the cerebrum divided? Is it completely divided? 
22. Is the surface of the human brain smooth? 
23. Do the convolutions vary in depth ? 
24. Do all animals have these convolutions? Name some that do 
not. 
25. Is the gray or white matter on the surface of the brain? 
26. What composes the bulk of the convolutions ? 
27. How do the convolutions affect the amount of gray matter? 
28. Where is the cerebellum? Of what does it consist? 
29. Where is the medulla? How large is it? 
30. Give a general description of the spinal cord. 
31. Where is its gray matter? Its arrangement resembles what'( 
32. How do the spinal nerves originate? 
33. Which are the motory fibers? Which the sensory? THE NERVOUS SYSTEM. 
267 
CHAPTER XXVI. 
THE PHYSIOLOGY OF THE NERVOUS 
SYSTEM. 
The Nerve Current. The peculiar force carried by the 
nerves from one part of the body to another is called 
the nerve current, or nerve force; it travels along the 
nerve at the rate of over one hundred feet a second. It 
is not known what this force is, although we do know 
what conditions favor it, and what check it. If the 
end of the finger be touched, almost instantly the sen- 
sation reaches the brain and is made known to the mind. 
But the nature of the force which conveys this sensa- 
tion along the nerves from the finger to the spinal cord, 
and then up the cord to the brain, is, as we have said, 
entirely unknown. 
The nerve current is set in operation by a stimulus. 
Suppose there is a desire to move the hand: in this case 
the stimulus is an act of the will, which excites the nerve 
current, so that it almost instantly passes down the nerve 
fibers to the muscles of the arm. When the nerve cur- 
rent reaches a muscle, the current itself acts as a stimu- 
lus, rousing the muscle to action. If we pinch the skin 
the stimulus is a mechanical one; the sensation is can 
ried to the nerve centers, over the sensory fibers. The 
pupil of the eye becomes smaller when a bright light 
is brought near the face: in this case, light is the stimu- 268 
THE ESSENTIALS OF HEALTH. 
lus which at last causes the muscle of the iris to con- 
tract. A sharp scream will cause a person standing 
near to jump; here fright is the stimulus. Thus we 
conclude that nerve currents, mechanical agents, light, 
and the emotions, may each act as a stimulus. 
Function of the Cerebrum. The cerebrum is the seat 
of the intelligence. It is here that we think, feel, and 
will. It is not known how the mind is connected with 
the brain. It is impossible to explain how it is that our 
intelligence depends upon the tissue of the brain. We 
simply know the fact that in some way the existence of 
our mind depends upon a normal brain. This has been 
proved in many ways. An injury to the head, resulting 
in a portion of the skull being fractured and pressed 
upon the brain, has been followed by loss of conscious- 
ness; and the person has remained in a deep sleep until 
the surgeon has raised the depressed bone, when con- 
sciousness has returned. 
Sickness has also proven it: an inflammation of the 
membranes of the brain, affecting its surface, causes de- 
lirium and otherwise disturbs the mind. Medicines 
which affect the flow of blood to the brain also inter- 
fere with the reasoning faculties. Persons born with 
extremely small brains have no intelligence. After re- 
moving the cerebrum all voluntary acts are abolished. 
Thus injuries, disease, drugs, size, and experiments all 
show that a healthy condition of the cerebrum is ne- 
cessary for the existence of intelligence and the power 
to will and to command. 
Two Brains. As stated in the preceding chapter, the 
cerebrum is nearly divided into two complete parts. 
This fact has led some physiologists to declare that THE NERVOUS SYSTEM. 
269 
there are two brains, and that they act independently of 
eacli other. It is nearer the truth, probably, to say that 
so far as the mind is concerned, the sides of the cere- 
brum should be considered as one whole organ, but that 
each side controls the sensation and motion of the oppo- 
site side of the body. 
Mind and Body. In some mysterious way, these two 
are so connected that what affects the one affects the 
other also. Therefore a healthy mind and a diseased 
brain cannot go together. As the same blood nourishes 
the brain that nourishes the other parts of the body, so 
the former cannot be in its best state unless the latter 
be in a healthy condition. From this it follows that if 
we would attain the fullest intellectual development, 
attention must be given to the laws of health, and their 
teachings strictly obeyed. 
Function of the Cerebellum. Injuries to the cerebellum 
do not necessarily interfere with either the will or the con- 
sciousness, but with the movements of the body. From 
this it would appear that the cerebellum is especially 
concerned in maintaining a harmony of action of the vol- 
untary muscles. Without the controlling power of the 
cerebellum, the muscles would act as irregularly as they 
do in one who is intoxicated. By its action we are able 
to keep an exact position ; and at all times can have the 
muscles act in harmony and with regularity. 
Functions of the Medulla. This part of the nervous 
system is one of great interest. It is most essential to 
life, and it controls many of the most important func- 
tions. In the medulla are many “ centers,” or small 
collections of nerve cells, which control certain func- 
tions. When these centers are stimulated in any way, 270 
THE ESSENTIALS OF HEALTH. 
they put into action the functions they control; as for 
example, there is a “ sneezing center.” If some irritant 
be inhaled into the nose the ends of the nerve fibers are 
irritated, and an impression is conveyed to the sneezing 
center; from this center goes forth a nerve current to 
certain muscles, which contract and cause the expulsive 
act of sneezing. Besides the sneezing center there are 
many others, among which are: the coughing center; 
the center for the secretion of the saliva; the vomiting 
center; the swallowing center; and the center for the 
closure of the eyelids. 
One of the most important centers is known as the 
respiratory center. It is a fact that a small collection 
of cells in the medulla controls absolutely all the 
movements of respiration. This small center has 
greater power than the will itself; for we may “ will ” 
not to breathe, and we can make the attempt to hold the 
breath, but soon we can do so no longer. Notwith- 
standing our greatest efforts, we again begin to breathe; 
for the center in the medulla is stronger than the will. 
We may be capable* of increasing or diminishing the 
number of respirations per minute for a short time; 
even cease breathing for a brief period; but soon the 
respiratory center exerts its power, and respiration is 
continued with wonderful regularity. 
Other important centers affect the movements of 
the heart. One center continuously holds the heart in 
check, causing it to beat with great regularity. An- 
other center appears to have an opposite effect at times, 
being capable of accelerating the action of the heart. 
No less important is the vaso-motor center. This 
controls the nerves which go to all the arterial system. THE NERVOUS SYSTEM. 
271 
It is a small collection of cells, yet it is capable of caus- 
ing the contraction, or relaxation, of the walls of any of 
the arteries. It will be remembered that in the walls 
of the arteries is a layer of involuntary muscle, arranged 
in a circular manner around the vessels; if the muscle 
contracts, the vessel will be narrowed ; while if it re- 
laxes, the vessel will be enlarged. The vaso-motor 
center presides over the action of the muscular walls of 
the arteries: the normal condition of this center is one 
which keeps the arterial walls in a moderate state of 
contraction at all times. The center is said to keep up 
the “ tone ” of the arteries, whereby their walls are held 
firmly in hand. When the function of this center is 
checked, it releases its hold on the arterial walls and 
they relax, thus enlarging the size of the vessel. If the 
blood vessels are thus made larger, more blood will flow 
through them, and the parts will be a deeper red in 
color. This is usually temporary, but it may become 
permanent. 
Blushing is a temporary checking of the power of the 
vaso-motor nerves of the face; they cease to act, thus 
allowing the muscles in the smaller arteries of the skin 
to relax; this results in a temporary enlargement of 
the blood vessels, so that more blood flows to the part. 
The vaso-motor nerves may become paralyzed, so that 
the blood vessels are permanently enlarged; this is the 
condition of the red nose of the confirmed inebriate. 
The vaso-motor center may act in an opposite man- 
ner to that described, — it may act with more than nor- 
mal power. The smaller arteries then have their mus- 
cular walls contracted with more vigor, so that the 
amount of blood in a part may be greatly reduced. 272 
THE ESSENTIALS OF HEALTH. 
Cold stimulates the vaso-motor center, so that if the 
hand be placed in cold water it soon becomes pale from 
loss of blood. Fright often causes the face to become 
pale, owing to the vigorous action of this center. 
This power of the vaso-motor center is most essential 
to the preservation of health, and even of life itself. 
Let us illustrate its daily action: the cold weather of 
winter stimulates the center so that it acts with in- 
creased power; this contracts the arteries of the skin, 
so that the flow of blood through it is greatly dimin- 
ished. Therefore the loss of animal heat is diminished, 
as we have already learned. But during the summer 
the vaso-motor nerves relax their hold oil the smaller 
blood vessels of the skin; the blood flows more freely 
through it, and the loss of heat is thereby increased. 
From all this we conclude that the vaso-motor center 
is capable of controlling the supply of blood to any part 
of the body. By increasing its normal function the 
arteries of any part are made smaller and the supply 
of blood correspondingly less; while by diminishing its 
normal work the arteries are made larger and the sup- 
ply of blood increased. It has certainly been proven 
that the medulla is a most important, as well as most 
delicate part of the nervous system. 
The Spinal Cord and Reflex Action. The spinal cord 
is the conducting medium between the nerve fibers of 
the lower part of the body, and the brain. 
A second function of the cord is a reflex one. It is 
a great reflex center; its action in this respect is al- 
most continuous. There are many familiar illustrations 
of this action in every-day life; tickling the foot of 
a person who is asleep causes the foot to be quickly THE NERVOUS SYSTEM. 
273 
withdrawn; this is purely a reflex act. The impression 
produced on the nerves of the foot is conveyed along 
the sensory fibers to the spinal cord, and from the 
cord it is “ reflected ” outward along a motory nerve to 
the muscles of the limb. The sensation produced by 
the tickling entered the cord through the posterior root 
of a spinal nerve, and immediately left it through the 
anterior root; this involved no interference of the brain. 
To make a reflex act, three things are necessary: an 
unbroken sensory nerve, for connecting the point touched 
and the nerve center; a healthy nerve center; and an 
unbroken motory nerve, between the nerve center and 
the muscles to be stimulated. Reflex action is partly, 
but not altogether, under the control of the will. To 
illustrate: if we inhale an irritating powder, like pepper, 
through the nose, we may be able to postpone the sneez- 
ing for a short time, but finally we are obliged to sneeze, 
and no power of the will can prevent it. 
Course of Nerve Current in Reflex Action. A glance at 
Fig. 98 will make clear the course of the nerve current 
in a reflex act. At the right, 3, is one of the spinal 
nerves. This large nerve consists of many fibers which 
proceed together until they reach some distant part, as 
the arm. Some of the fibers terminate in the skin, and 
others in the muscles. If the skin on the arm be touched 
the stimulus will be conveyed toward the spinal cord and 
will finally enter it through the sensory root, at 2. The 
nerve current then goes directly through the gray mat- 
ter to the anterior or motory root, at 1; it then passes 
down the motory fibers, which are alone at 1, but which 
are soon side by side with the sensory fibers in the 
spinal nerve, at 3. After continuing the length of the 274 
THE ESSENTIALS OF HEALTH. 
motory fibers the current finally stimulates some of 
the muscles of the arm and they respond by a vigor- 
ous contraction. Thus it is seen that the sensory and 
motory fibers are separated into distinct bundles at 
their beginning, and they are also separated at their 
termination, the former in the skin and the latter in 
the muscles; but they were together in one bundle 
through all the distance between. A reference to 
Fig. 99 may aid in making the subject more clear. 
The nerve current travels in the direction of the arrow- 
heads. 
Importance of Reflex Action. I he daily work of the 
body is carried on largely as a result of reflex action. 
The flow of saliva produced 
by mastication is a result of 
reflex action; and we could not 
check the flow if we desired. 
The flow of the gastric juice, 
from the stimulus of food in 
the stomach, is purely a re- 
sult of reflex action. Respi- 
ration is a reflex act, due to 
certain stimuli applied to the 
respiratory center in the me- 
dulla. The nervous system 
is constantly performing a vast amount of labor of which 
we are unconscious, and which we are unable to alter, 
except possibly to a limited degree in a few instances. 
Fig. 99. A diagram illus- 
trating reflex action : s, the skin, 
M, a muscle. If the skin, s, be 
touched the nerve current travels 
in the direction of the arrows 
until it stimulates the muscle, M, 
to contract. 
Acquired Reflex Action. Many acts which are at first 
voluntary, and which are performed only by a strong 
effort of the will, finally become so natural and easy 
that they are performed unconsciously; these may be THE NERVOUS SYSTEM. 
275 
called acquired reflex acts. Walking was a very diffi- 
cult process at first, and could only be accomplished 
with considerable effort. The number of muscles 
brought into play in running and jumping is very 
great; yet they all relax and contract at just the 
proper time, without the least aid from the will. When 
the beginner plays the piano, he not only looks at the 
music, but also at the keys, that only the right ones 
may be touched; but after a time the sight of a par- 
ticular note calls forth such a movement of the hand 
that just the proper key is touched ; the performer looks 
at the music, and the hands take care of themselves. 
The first trials at skating are not highly successful; all 
the power of the will has to be exercised to keep the 
balance and to move in the desired direction ; but soon 
the movements become easier and the exercise becomes 
a pleasure and a rest. 
Habit. A habit is an action acquired by frequent 
repetition. It is a law in physiology that each time 
a nerve cell acts in a particular way, it gains a power 
that makes the second act more easily performed. In 
this way a habit is formed : it may be the habit of walk- 
ing, skating, or playing the piano; it matters not what 
the acts are, provided the nerve centers become accus- 
tomed to their repetition. At first, it was difficult to 
say the alphabet correctly, but now that we are in the 
habit of saying it, we can repeat it correctly more easily 
than incorrectly. It took an effort of the will at first to 
say it correctly, while now it requires much more will 
power to say it incorrectly; in other words, it takes a 
direct effort of the will to break the habit of saying it 
correctly. 276 
THE ESSENTIALS OF HEALTH. 
This clearly proves two things: first, by the frequent 
repetition of an act we soon become quite unconscious 
of it; and second, it requires a direct effort of the will 
to break the habit. From this it follows that the nerve 
centers will have a strong tendency to do whatever they 
have been in the habit of doing. Thus there is sound 
reasoning in the statement that one kind act makes the 
way easier for another to follow. One duty performed 
makes another more easy; each pure thought invites 
another of its kind. Each temptation conquered 
makes us more sure of future victory. In youth, before 
the nerve centers have formed their life habits, it is 
comparatively easy for us to lay the foundation of 
future usefulness. Such, at least, is the teaching of 
physiology. 
Life is a hard battle at its best, and if we would make 
it a grand success we need all tlie help we can get from 
every possible source. Physiology teaches us that by 
the repetition of what may seem trifling deeds, we can, 
while still young, form the habit of breaking the laws 
of health ; it teaches us what the result of such actions 
will be; and it also teaches us that no person can avoid 
these results without avoiding their causes. On the 
other hand, we learn from this stern teacher that it is 
easy, while yet young, to form the habit of right living, 
so that we may build up both body and soul for future 
usefulness and happiness. THE NERVOUS SYSTEM. 
277 
CHAPTER XXVII. 
THE HYGIENE OF THE NERVOUS 
SYSTEM. 
Necessity of a Healthy Nervous System. We have 
learned that all the functions of the body are dependent 
upon the activity of the nerve centers: these must be 
in the best condition, or the parts under their control 
will suffer. The nervous system is so closely related 
to the other parts of the body that an injury of any 
kind to the one is sure to affect the other. 
Heredity. One of the things necessary for a vigorous 
nervous system is its inheritance. The old saying that 
“ blood will tell ” is as true to-day as when it was first 
uttered. We not only inherit the forms and the feat- 
ures of our parents, but also, to a certain degree, their 
dispositions, their powers of endurance, their likes and 
dislikes, and even their moral characters. The laws of 
heredity are very strong, and, in the long run, they are 
true. A child has a wonderful, almost inestimable 
gift, if endowed by birth with a sound and strong nerv- 
ous system free from physical and moral ills. Such a 
child has a start in the world far in advance of others 
less highly favored, while his efforts to lead an upright 
life are much more easily crowned with success. The 
less favored child, who inherits a nervous system 
shattered and weakened by the vicious habits of his 278 
THE ESSENTIALS OF HEALTH. 
ancestors, enters life at a disadvantage, while he has a 
constant fight with himself to conquer a natural ten- 
dency to do evil. When at last his better nature rules, 
and he completely masters himself, he comes off a 
glorious conqueror. 
A Healthy Body. Even with a vigorous nervous system 
and a strong moral nature transmitted to us, all our 
bright prospects may be easily blasted by neglecting to 
obey some of the well-known laws of health. To develop 
the nervous system requires proper food, pure air, and 
plenty of mental and physical exercise. Physical pain 
is not conducive to the best brain work; a tired body 
will not stimulate the brain to action ; hence we con- 
clude again that a healthy body is necessary for the high- 
est and best development of the whole nervous system. 
Exercise of the Mind. As muscular exercise is essen- 
tial to the full development of the muscles, so mental 
exercise is necessary if the best efforts of the brain are 
desired. This exercise must be regular, persistent,'and 
properly suited to the age and health of the person. It 
is impossible for the boy to jump so far at the first 
trial as he will after weeks of practice; neither can he 
perform so severe mental work at first as he will after 
months of constant study. 
If the muscles have not been previously trained, one 
hard effort at lifting or running may cause severe pain 
and soreness in them. So an extra effort of the mind 
for one unaccustomed to study may cause headache and 
even severe mental disorders. The evils of over-study 
and of crowding too many studies into each school year 
are being more fully understood and corrected, while 
more attention is being given to a better understanding THE NERVOUS SYSTEM. 
279 
of the laws of health. The modern teacher knows that 
a pupil with a healthy body is much more likely to have 
a vigorous mind; and that the proper care of both 
should go hand in hand. 
Mental labor ought not to cease with the school life; 
the school is to discipline and train the mind so that 
the powers of observation and reasoning may continue 
throughout life to the best possible advantage. “ Work ” 
is the word that contains the secret of a healthy body 
and a well-balanced mind, — regular, systematic, persis- 
tent work, both for the body and the mind. Pleasures 
are more enjoyable, and amusements are more profitable, 
if they be but the short vacations in our daily duties. 
A life of idleness and pleasure-seeking is not the normal 
condition of any human being. 
Rest. The mind, as well as the body, would soon fail 
if it were obliged to work too hard or too long. Rest 
is absolutely necessary for all parts of the body. Many 
individuals seem to think that rest means to fold the 
hands and remain in perfect idleness ; as a rule this is 
the poorest method of obtaining rest. If we have been 
exercising the mind until we are tired from study, noth- 
ing will restore the mental vigor better than some gentle 
out-door sport, as a brisk walk. The exercise brings a 
good supply of fresh blood to the brain, and thus aids in 
giving new life to its tissue. 
The headaches of school children often cease before 
they have reached their homes at the close of day. 
Amusements, excursions, and a change in the character 
of the work, all tend to repair the waste of nervous 
energy, and are far better than idleness. Complete 
rest and quiet are not conducive to health unless 280 
THE ESSENTIALS OF HEALTH. 
for particular reasons they have been ordered by a 
physician. 
Worry. Above all things do not worry. Study hard, 
play hard, enter with enthusiasm into all the duties and 
pleasures of school life, but do not worry. Worry 
means waste, — waste of nervous force, of thought, of 
memory ; and it is a sure road to the impairment of the 
highest functions of the brain. While it is true that 
some students do not have anxiety enough for their work, 
yet it is equally true, especially in the higher grades, 
that many attempt to accomplish altogether too much. 
Sleep. One of the great restorers of both mind and 
body is sleep. All animals having a well-developed ner- 
vous system take rest in sleep. Drowsiness and weari- 
ness warn us that sleep is necessary. These warnings 
may be unheeded for a time, but sooner or later we 
have to yield to the imperative demand. Some persons 
require more sleep than others, but the adult needs, on 
the average, from seven to nine hours. It is said that 
Napoleon required but three or four hours sleep each 
day, and that he would pass days with very little rest of 
any kind. Frederick the Great required but little sleep, 
not over five hours a day. These are marked exceptions, 
though it is a fact that nearly all our great men who are 
obliged to do an immense amount of brain work sleep 
well and long; they know the value of a good night’s 
rest, and are alarmed when they are unable to procure 
sleep. They know that during their busy days the 
waste is greater than the repair, and that during the 
quiet rest of the night the cells are busy repairing the 
waste, and appropriating new material for the labor of 
another day. THE NERVOUS SYSTEM. 
281 
Insomnia. Continued wakefulness often becomes a 
very serious affection, and many men have lost their 
health by the inability to sleep. If persistent, it is a 
dangerous trouble and should be remedied at once, if 
possible. 
To promote Sleep. There are many popular ways of 
promoting sleep, nearly all of which make a bad matter 
worse. Out-door exercise during the day, light suppers, 
quiet evenings, and warm feet will greatly promote 
sleep. “ Keep the head cool and the feet warm.” But 
sleep will often refuse to come if the tired brain is filled 
with cares, griefs, and anxieties. 
Students need Much Sleep. Students often make a 
great mistake in trying to change the laws of nature, 
and in studying until late into the night, and then in 
sleeping away the morning hours. It is only necessary 
to remember that at night the brain is tired, and an 
extra effort is necessary to make an impression upon it; 
while in the morning it is fresh and sensitive and easily 
impressed ; the morning is the time for study. Earnest 
application in the early part of the day, concentrating 
the mind with all the power of the will, and laying aside 
everything else but the work in hand, — these will soon 
prove that the mornings were made for study, the even- 
ings for relaxation, and the nights for sleep. 
1. What do you understand by the “nerve current?” 
2. flow fast does it travel ? 
3. What sets the nerve current in operation? Illustrate this. 
4. How has it been proved that the cerebrum is the seat of the 
intelligence ? 
5. Do injuries to the cerebellum necessarily destroy consciousness ? 
QUESTIONS. THE ESSENTIALS OF HEALTH. 
282 
6. What is the especial function of the cerebellum? 
7. What is said of the medulla in its relation to life? 
8. Name some of the centers in the medulla. 
9. What controls the movements of respiration ? Illustrate this. 
10. What centers affect the movements of the heart? 
11. What center controls the nerves which are in the walls of the 
arteries ? 
12. What is the normal condition of this vaso-motor center? 
13. When the function of this center is checked, what occurs? 
14. Give the physiology of blushing. 
15. When the vaso-motor center acts with more power than the 
normal, what occurs? 
16. What is this center capable of doing? 
17. The spinal cord is a connecting medium between what? 
18. Give another function of the cord. How illustrated ? 
19. What three things are necessary for a reflex act? 
20. Is reflex action ever under the control of the will? How 
illustrated ? 
21. Describe the course of the nerve current in a reflex act. 
22. Give some illustrations showing the importance of reflex 
action. 
23. Are reflex acts ever acquired ? Give illustrations. 
24. Give a definition of a habit. 
25. Give some illustrations showing that by frequent repetition of 
an act we may become unconscious of it. THE NERVOUS SYSTEM. 
283 
CHAPTER XXVIII. 
ALCOHOL AND THE NERVOUS SYSTEM. 
After the habit of indulgence in alcoholic drinks has 
been fully established it has such a mastery over the 
whole system that statements or warnings of any kind 
have little effect. But it is doubtless true that if all 
young men knew the effect of alcohol on the nervous 
system, before they began to use it, few, if any, would 
ever try the experiment of taking the first glass ; while 
it is certainly as true that no right-minded young 
woman, possessed of a like knowledge, would ever think 
of offering a glass to a friend. 
It is because of the ignorance of the terrible power 
hidden in strong drink that young men ever begin the 
use of alcohol as a beverage. “ One glass certainly can- 
not do me any harm,” is the oft repeated statement. 
The student of physiology knows full well, though, that 
even the one glass, repeated now and then, has the power 
to make such changes in the tissues and organs of the 
body, and to produce such a marked effect on the nerve 
centers that breaking away from it will be very difficult. 
And some day it will be discovered, when too late to re- 
treat, that a habit has become fastened with wonderful 
tenacity. 
There are two classes of persons who begin the use of 284 
TIIE ESSENTIALS OF HEALTH. 
alcoholic beverages : those who honestly think there may 
be some healing virtue in their power, and therefore take 
some form of alcohol as a tonic ; and those who do so 
for no particular reason, only because they are asked. 
The persons of the first class are deceived by the pri- 
mary narcotic effects of the alcohol, which by deadening 
the nerves makes them feel better for a time, and so the 
doses are repeated until the habit is formed. 
Many physicians have erred in prescribing some form 
of alcohol as a regular medicine, under the mistaken 
impression that it is a food and tonic. All at once 
the patient discovers he has a most unnatural desire 
for his medicine, and is powerless to give it up. To 
such as believe that there is virtue in alcohol as a tonic, 
and that its use will be of benefit to them in restoring 
health, we can only say : Never prescribe it for yourself 
any more than you would prescribe opium or strychnine, 
or any other poison. 
The wise physician of to-day, who is abreast with the 
modern investigations concerning this drug, knows how 
little virtue there is in the various forms of alcoholic 
beverages as a real aid in combating disease. Doubt- 
less a great deal of alcohol used as medicine comes from 
the self-prescribing of those who take it because they like 
it. A better understanding of its physiological action 
has made it necessary to regard alcohol as a dangerous 
poison. Some of the most competent medical men in 
this country have openly declared that for many years 
they have never ordered a single dose of alcohol in any 
form, and that there are better and safer remedies which 
can be given in its place. 
To tlie second class belong those who are beginning THE NERVOUS SYSTEM. 
285 
the use of alcohol because some one offers to treat them 
and they do not wish to refuse. To these, and also to 
all who have not ventured thus far, we would say : 
Study carefully the following effects of alcohol on the 
nervous system, and then calmly decide whether the 
path is not altogether too treacherous and dangerous 
to enter upon. 
The most striking thing about alcohol is that it has a 
special affinity for nervous tissue. By “ affinity ” is 
understood the attraction which takes place between the 
alcohol and the tissues of the body. When alcohol is 
taken into the body it affects all the living tissues, but 
it affects them in different degrees ; it has some affinity, 
or attraction, for muscles, some for the blood, some for 
the liver, and so on ; but of all the tissues in the body 
it has the strongest affinity for those of the nervous sys- 
tem. Thus, if after death from the effects of alcohol, 
the tissues are separately analyzed by the chemist, more 
alcohol will be found in the brain and spinal cord than 
in any other tissue. 
The brain is the throne of the intellect, and yet it is 
attacked the most severely of any of the tissues. Where 
man is strongest, there does alcohol make its most 
powerful attempt to overthrow him. Many a simple 
drug can do great damage in time by persistently at- 
tacking one of the less important tissues. Many diseases 
affect the less important organs and tissues at first, and 
it is only after years of annoyance that the general 
health becomes undermined. But alcohol strikes at 
once with its full power at that which is highest and 
most important to man. 
In the preceding chapter it is taught that the nervous 286 
THE ESSENTIALS OF HEALTH. 
system controls all the functions of the body ; anything 
which affects the governing body must affect the parts 
governed. So we find alcohol affecting with the greatest 
severity that which is the most central and vital. Its 
affinity for nervous tissue is so great that it has been 
found in the fluid normally present in the brain, and it 
has even been distilled from the brains of those who 
have died after using large quantities of it. 
When alcohol is taken into the body in the form of 
some kind of drink, it is absorbed into the circulation 
and is carried to all the tissues of the body, more going 
to the nervous tissue than to any other. Its effect on 
this tissue is that which must follow from the adminis- 
tration of any powerful narcotic. Alcohol paralyzes 
nerve tissue. A standard medical work on the action 
of the various drugs on the human system, classifies 
alcohol with “ those remedies which diminish or suspend 
the functions of the cerebrum after a preliminary stage 
of excitement.” Webster says that paralysis is the com- 
plete or partial abolition of function. Therefore we are 
correct in stating that alcohol paralyzes nerve tissue; 
for it completely or partially abolishes the functions of 
the nervous system. 
A standard writer on materia medica says that the 
effects of alcohol are expended chiefly on the nervous 
system; this fact alone is enough to condemn its use in 
any form as a beverage. But it makes itself appear to 
good advantage before those who do not know its full 
effects, because of its power to first excite the brain. 
We understand the cause of this excitement when we 
know that alcohol paralyzes, and so checks the action of 
the vaso-motor center, causing the latter to release its THE NERVOUS SYSTEM. 
287 
hold over the muscular walls of the small arteries. As 
a result the vessels expand and more blood flows through 
them, and following this enlargement of these smaller 
blood vessels the distant pressure is removed and the 
heart beats faster. The more rapid flow of blood and 
the enlarged blood vessels bring an extra supply of 
blood to the brain and thereby it becomes greatly ex- 
cited. The flushed face is the result of the same 
changes; the walls of the smaller arteries are relaxed 
and the vessels become filled with blood, thus causing 
the skin to appear red. In the light of these facts we 
must regard the flushed face and the excitement of the 
brain as symptoms of a temporary paralysis of the nerves 
which control the circulation of the blood in the smaller 
arteries. 
Following the brief period of excitement produced by 
alcohol, other effects appear. The spinal cord becomes 
involved, as shown by the irregular action of the parts 
under its more immediate control. It is unable to fully 
perform all reflex acts, and the will has to come to its 
aid. Thus the act of walking becomes uncertain, and it 
requires the aid of the will to order the movements of 
the proper muscles. The loss of some of the power of 
the spinal cord is also shown in the trembling of the 
lips and the uncertain and indistinct speech. A little 
later the cord loses much of its force as a nerve center, 
and its control over the muscles is slight; then the mus- 
cles of the lower limbs become weak and the gait is 
staggering. All this means a temporary paralysis of 
the nerve centers. The centers in the medulla soon 
become affected, and vomiting is likely to occur; this 
may prove beneficial by throwing off the poison, but 288 
THE ESSENTIALS OF HEALTH. 
usually the alcohol has been all absorbed from the 
stomach before vomiting takes place. 
When the stage of excitement, or increased action of 
the brain cells, is at its height, the cerebrum acts in a 
still more excited manner; the nerve cells become over- 
excited, and the animal nature of man assumes control; 
the reason is overpowered and man is brought to a level 
with the lower animals. The muscles are no longer un- 
der control, and the whole system seems to be ruled by 
some strange outside power. The stage of excitement 
is soon over, and gradually the entire brain loses its 
power; the voluntary muscles no longer act; all sensa- 
tion is lost; and the body becomes nothing more than 
a wonderful piece of disordered mechanism. “ The 
functions of the cerebrum are suspended.” 
Yet the centers in the medulla are still active, for the 
heart continues to beat and the respiratory muscles con- 
tinue to act. These two centers would soon become 
paralyzed also, and the heart and lungs would cease to 
do their work, were it not that by reason of unconscious- 
ness the person takes no more alcohol. Herein lies the 
explanation why alcoholic drinks do not cause more sud- 
den deaths ; the brain loses its power before the heart 
ceases to beat. In other words, the poison affects the 
cerebrum before it does the medulla. The man becomes 
unconscious before he has taken enough to check the 
action of all the centers in the medulla. 
If alcohol affected the nerves which keep the heart in 
motion before it did the consciousness, it would cause a 
vast number of sudden deaths. But it may be urged 
that this is an over-drawn picture ; that it is an illustra- 
tion of drinking to complete intoxication, and that even Tilt: NERVOUS SYSTEM. 
289 
those addicted to the use of alcohol do not favor such 
excesses. We must, therefore, study the effects of mod- 
erate and frequently repeated doses of alcohol on the 
nervous system. 
We must fully understand that alcohol has an im- 
mediate and direct effect on nerve tissue. By direct 
effect is understood the effect produced by actual con- 
tact of the alcohol with the nerve tissues; for some of 
the alcohol taken into the system comes in direct con- 
tact with the brain, producing most marked changes in 
the structure of that organ. This statement has been 
proven by experiments, by chemical analysis, and by 
microscopical examinations, — sustained by the reports 
of eminent men. The structure of the brain is also 
changed, indirectly, by the poorer quality of the blood, 
by the impaired circulation, and by the diminished ac- 
tivity of the organs of excretion; thus the supply of 
blood is less, the blood itself is poorer in quality, and 
the channels for the removal of the waste and worn- 
out materials are not sufficiently active. 
As a result of both the direct and indirect effects of 
alcohol the following marked changes are produced. An 
eminent medical authority says that after the continued 
use of alcohol “ the nerve cells of the gray matter are 
more or less fatty and shrunken.” As a result of this 
shrinkage he says, “ The whole cerebrum becomes 
smaller, and the space thus made becomes filled with 
a watery fluid.” It is impossible to place too much 
emphasis on this statement. This was written to physi- 
cians and medical students as a statement of the facts 
concerning the action of one .of the many drugs used in 
the practice of medicine. 290 
TIIE ESSENTIALS OP HEALTH. 
What is the teaching of this high authority ? That the 
continued use of alcohol actually lessens the size of the 
brain; reduces the capacity of man to think; changes 
the mysterious and wonderful nerve cells so that they 
are smaller and partly changed to fat. Space once occu- 
pied by brain tissue becomes filled with water. Thus, 
in this cool and logical way, are we brought face to face 
with the astounding anatomical fact, that alcohol has the 
power to “ steal away the brains.” “ The evidences of 
these changes in the brain and cord,” the same au- 
thority says, “ are seen in the impaired mental power, 
the muscular trembling, and the shambling gait of the 
drunkard.” 
It would seem to any logical mind that nothing more 
need be said to prove the baneful effects of strong drink. 
The knowledge of the system already acquired from a 
study of the preceding chapters, must be sufficient to 
show how surely alcohol will do its work, and also how 
severe that work will be. 
But testimony accumulates on every hand. Dr. Wil- 
liam A. Hammond, the eminent specialist on nervous dis- 
eases, made a careful study of the effects of alcohol on 
the nervous system. If it had any special virtue he was 
desirous of employing it in his practice. By numerous 
experiments he proved its powerful poisoning effects. 
He says : “ Mankind would be better mentally, morally, 
and physically, if the use of alcohol were altogether 
abolished.” 
Delirium Tremens. This is one of the horrible effects 
of alcoholic poisoning. It may follow the sudden use 
of a large quantity of alcohol, even from a single intoxi- 
cation, although it is usually the result of the free and THE NERVOUS SYSTEM. 
291 
long continued use of alcoholic drinks. There is no 
telling at what time it may attack its victim ; it may 
be when he first begins his career, or after years of 
continued drinking; it may come to those physically 
strong, or to the very weakest. It is one of the most 
horrible effects of alcohol, transforming man into the 
wildest and fiercest of animals. There is inability to 
retain food and all the voluntary muscles are in a 
tremor; the patient is either unable to procure sleep at 
all, or there are brief periods of sleep, interrupted by 
the most terrifying dreams; he is being constantly 
pursued by horrible insects and reptiles, while he is 
unable to escape from them, or to destroy them. Re- 
covery may take place after days of intense agony, or 
death may bring relief at any moment. 
THE EFFECT ON THE MIND. 
From the preceding statements it logically follows 
that the use of alcohol diminishes the will power. Men 
who are proud of their dress and speech, and who pride 
themselves on their proper decorum, become foolish and 
silly when slightly intoxicated, and are easily provoked 
to do rash things. A small boy can so provoke a slightly 
intoxicated man by imitating him that the man appears 
to lose all control of himself. Even a small amount of 
strong drink is sufficient to make some people more 
easily annoyed and disturbed than when perfectly free 
from the effects of alcohol. Thus we reason that the 
man who indulges in strong drink, but not to the extent 
of intoxication, does not have full control of his mental 
and moral powers. He is more easily provoked and 292 
THE ESSENTIALS OF HEALTH. 
more readily yields to temptation. Man needs all the 
will power he can command, to successfully meet the 
many trials and battles of life. To take strong drink 
is to weaken his mental power, and by so much to di- 
minish his chances of success in any of the useful activi- 
ties of life. 
To the conclusions of logic and the positive statements 
of medical authority as to the undermining and weaken- 
ing of the mind by alcohol, there may be added the tes- 
timony gathered from the records of courts and prisons. 
Statistics show that a large percentage of the various 
crimes are committed while the, persons are under the 
influence of liquor. Alcohol blunts all the finer sensi- 
bilities, and destroys the love for justice and fair play. 
The mind is trampled upon and the lower animal nature 
rules the body. As a result, deeds are committed which 
would never be considered for a moment if the higher 
nature were in command; or, in other words, if the king 
were on his throne. 
Other diseases of the nervous system result from the 
use of alcoholic beverages. The statistics of the insane 
asylums show that insanity is one of these results. 
What can be more terrible than to see a promising 
career end in the loss of reason, and to find that strange 
and wild fancies occupy its place ? In France, during 
the last war with Prussia, it was found that over one- 
lialf of all the cases of insanity were occasioned by the 
use of alcohol. In the lunatic asylum at Dublin, “ nearly 
one half of the eases were known to be caused by the use 
of alcohol alone.” In America the proportion is not so 
great, yet it is surprisingly large. It is safe to assert 
that of one hundred insane persons, twenty are so afflicted THE NERVOUS SYSTEM. 
293 
as a direct result of the use of alcohol, and thirty-five 
more as an indirect result, making in all fifty-five of each 
one hundred insane persons so afflicted on account of the 
use of alcohol in some form. 
Still another effect is seen in the weak nervous sys- 
tems transmitted by drinking parents to their children. 
Some form of nervous disease is very generally inherited 
from parents addicted to strong drink ; this transmission 
makes their children less able to withstand the various 
diseases of childhood. The number of children who 
die from weak constitutions, inherited from intemperate 
parents, is very large indeed. With stronger constitu- 
tions they would be able to survive many of the ailments 
incident to childhood, but they appear to have no power 
to resist disease. One of the prominent causes of infant 
mortality in our large cities, if the truth were only told, 
would be inherited alcoholic poisoning. 
The children of intemperate parents are likely to grow 
up weak in body and mind. Some go to the idiot asy- 
lums, some to the jails and prisons, while some go to 
the retreats for the insane. Others, however, manfully 
fight the battle; though tempted as none others are 
tempted, they conquer ; though naturally weak, they de- 
velop strength ; and though they inherit a love for strong 
drink, they persistently fight for its overthrow. 
No battlefield has records of victories more noble. 
When these triumphs are gained, the tide of evil is 
turned back forever; a fine mental organism and great 
will power, the constituents of greatness, are gained; 
and the person who inherited weakness is now a source 
of strength to all who are associated with him. 294 
THE ESSENTIALS OF HEALTH. 
OPIUM. 
Opium is a most powerful drug, and is classed with 
alcohol in its power, first, to excite, and then suspen 1 
the functions of the cerebrum. Its effects are more 
pronounced than those of tobacco, and are fully as 
severe as those of alcohol. In this country the opium 
habit is generally formed as a result of the use of opium 
to relieve pain. The individual has usually been a great 
sufferer and the physicians have been obliged to prescribe 
some form of opium to give relief. From these prescrip- 
tions for relief from pain the patient has sometimes been 
left with a strong desire for more opium, and by repeat- 
edly yielding to the desire the habit has been formed. 
The effects of opium on the nervous system are most 
pronounced ; it causes a partial paralysis of the lower 
limbs, giving a stooping or creeping appearance; it so 
interferes with all the functions of the body that the 
nerve centers suffer greatly from the want of nourish- 
ment. Opium has a wonderful power to blunt the moral 
sensibility; the opium-eater will do anything to obtain 
the drug ; the mind soon becomes enveloped in a cloud, 
and he goes about in a dazed stupor. All interest in 
business and friends is lost, and the one dominant idea 
is how to procure more of the drug; to do this he will 
almost invariably deceive in every possible'way. If lie 
is unable to get his accustomed dose he suffers the most 
terrible pains both in mind and body. THE NERVOUS SYSTEM. 
295 
QUESTIONS. 
1. What knowledge would probably keep young men from begin- 
ning the use of alcohol ? 
2. What two classes of persons begin the use of alcoholic 
beverages ? 
3. How are those of the first class deceived ? 
4. How must we regard alcohol ? 
5. What do some competent medical men declare ? 
6. What advice is given to the second class of young men? 
7. What is the most striking thing about alcohol ? 
8. What do you understand by affinity ? 
9. What tissue is attacked most severely by alcohol ? 
10. How does alcohol affect nervous tissue? 
11. With what remedies is alcohol classed? 
12. Give a definition of paralysis. 
13. Where are the effects of alcohol chiefly expended? 
14. How does it make itself appear to good advantage ? 
15. What is the result of checking the action of the vaso-motor 
center ? 
16. What effect does the extra supply of blood have on the brain? 
17. What follows the brief period of excitement produced by 
alcohol ? 
18. What do the trembling lips and the uncertain speech show? 
19. When the stage of excitement is at its height, how does the 
cerebrum act? 
20. How is the reason affected ? 
21. Describe the condition after the stage of excitement is over. 
22. Why do not alcoholic drinks cause a greater number of sudden 
deaths ? 
23. When taken into the system, does alcohol ever come in direct 
contact with the brain ? 
24. How does alcohol affect the brain? 
25. How does it affect the will power? 
26. What do the statistics of insane asylums show? 296 
THE ESSENTIALS OF HEALTH. 
CHAPTER XXIX. 
THE SENSE OF SIG-HT. 
Protection for the Eyes. The eyes are well protected 
in deep sockets of bone, called the orbits. Externally 
they are protected by the eyebrows, the eyelids with 
their glands, and the lachrymal glands. The nose 
is also a valuable protection to the eyes. 
The eyebrows pro- 
ject over the eyes and 
are covered with a 
thick growth of hair. 
The hair is directed 
obliquely outwards, so 
that the perspiration 
from the forehead is 
carried to the side of 
the face, instead of 
running directly down 
into the eyes. 
The eyelids are thin 
curtains placed direct- 
ly in front of the eye- 
balls. In the center 
of each eyelid is a thin 
plate of cartilage, on the outside of which is a thin 
muscle covered with skin. The inside of the lids is 
lined with a delicate membrane, called the conjunctiva. 
Fig. 100. The muscles of the right 
eyeball. The outer bony walls of the or- 
bit have been removed. (1) the muscle 
which turns the eyeball upward ; (2) 
downward ; (3) outward ; a correspond- 
ing muscle on the inner side moves the 
eyeball inward; (4, 5,) muscle which 
rotate the eyeball; (6) a pulley, through 
which the tendon of the muscle (5) moves. THE SENSE OF SIGHT. 
297 
On the edges of the lids is a row of delicate hairs, called 
eyelashes. They protect the eyes from insects and par- 
ticles of foreign matter; for the moment any foreign 
bodies come in contact with the lashes the lids close, 
thus preventing the objects from touching the eyeball. 
The eyelids keep the heat and cold from the more deli- 
cate parts of the eye, and they also keep out an excess 
of light. Their most important function is to cleanse 
the eyes and to keep them moist. Their rapid and fre- 
quent movements thoroughly remove any particles of 
dust from the front of the eyeball, while at the same 
time they moisten the surface. This is the object of 
winking, which is usually a reflex act, although it may 
be made voluntary. 
The Oil Glands. Oil glands are situated at right 
angles to the free edges of 
the lids, and on their in- 
ner side. They can be 
seen on the inner surface 
of the eyelids through the 
mucous membrane, look- 
ing like strings of minute 
pearls. They extend near- 
ly across the entire width 
of the lids, on the edges of 
which they open and pour 
out their oily secretion. 
This keeps the lids from adhering to each other, and 
holds hack the tears so that they do not run over the 
edges and down upon the face. 
Fig. 101. The eyelids of tlie right 
eye, viewed from the inside : (1) the 
lachrymal gland ; (2) the oil glands 
in the eyelids. 
The Lachrymal Gland. The lachrymal gland is an 
almond-shaped body situated in the outer and upper 298 
THE ESSENTIALS OF HEALTH. 
part of each orbit, between the eyeball and the bone. 
From this gland there extend about seven ducts or 
canals, which open on 
the inner surface of 
the upper eyelid near 
its outer part. The 
openings are ar- 
ranged in a row, as 
represented at 2, Fig. 
102, thus distributing 
the secretion over the 
surface of the con- 
junctiva. 
The Tears. The 
watery secretion 
from the lachrymal 
glands is known as 
The lachrymal fluid. 
The secretion is a con- 
stant one, although we are unconscious of its presence 
until there is an excessive flow; the fluid is evenly dis- 
tributed by the movements of the eyelids. An excessive 
amount of this secretion is called the tears. They are 
easily excited by irritants placed to the eye or nose; by 
laughing and crying; and by various mental emotions. 
Fig. 102. Front view of the right eye, 
showing the location of the lachrymal gland 
and the nasal duct: (1) the lachrymal 
gland ; (2) the ducts that carry the secre- 
tion from the gland to the free surface of 
the eyeball; (3) the duct for the passage 
of the secretion to the nose. 
Some of the secretion is evaporated from the eyeball, 
but the greater part of it escapes from the eye through 
regular channels provided for it. The secretion flows 
toward the inner angle of the eye where it enters two 
openings, one in either lid. This opening is easily seen 
on the lower lid as a black point in the center of a little 
eminence near the inner corner of the eye. The black THE SENSE OF SIGHT. 
299 
points are the beginnings of two ducts which pass in- 
ward toward the nose, as seen at 3, Fig. 102. 
The Eyeball. The eyeball is securely protected from 
injury and yet it has a most extensive range of sight. 
It is a round body with the exception that its front part 
protrudes more than the other parts. From the front to 
the back it is about an inch in length. 
The eyeball has three membranes or coats surround- 
ing it. The outer coat consists of two parts; the poster- 
ior part, which is very thick and hard, is seen coming 
toward the front of the eye where it is called “ the white 
of the eye.” Because it is so very tough and hard, it is 
called the sclerotic; the anterior part of this outer coat 
is transparent and is called the cornea. Through this 
transparent cornea the light passes into the interior of 
the eye. 
The middle coat of the eye is called the choroid; it 
is filled with dark pigment which makes it look quite 
black. The choroid joins a membrane in front, called 
the iris, in the center of which is an opening, called 
the pupil. In the iris are, the cells, containing a color- 
ing matter, which give the characteristic color to the 
eye. The size of the pupil can be changed by the ac- 
tion of certain muscles: the muscles are involuntary so 
that they only contract and relax as a result of some 
influence outside of the will. A bright light will make 
the muscles of the iris contract so that the pupil be- 
comes much smaller, and thus but little light reaches 
the interior of the eye. If the light be very faint, other 
muscles of the iris contract, enlarging the pupil, and 
thus allowing more light to enter. 
The third, or inner coat of the eye is called the retina. 300 
THE ESSENTIALS OF HEALTH. 
The miscroscope shows that it has a most complicated 
structure, and that it is directly connected with the 
fibers of the optic nerve, which go directly to the 
brain. When light reaches the interior of the eye, it 
Fig. 103. A section through the eyeball: Ca, the cornea, or the trans- 
parent membrane which forms the front of the eye ; s, the sclerotic ; 
c, the choroid; k, the retina; o, the optic nerve; b, the blind spot ; 
i, the iris ; l, the lens; ah, the aqueous humor ; vh, the vitreous humor. 
produces a peculiar impression on the retina ; which 
impression is then conveyed along the optic nerve to 
the brain; the brain transforms the impression made 
upon it into the sensation of vision, and we declare we 
are able to see. When any object is viewed the exact 
image of it is produced on the retina. If the optic nerve 
be cut the image will still be formed, but no sensation of the sense op sight. 
301 
light will reach the brain. Therefore, as it is the photog- 
rapher who sees and not his camera, so it is the brain 
which sees and not the eye, for the eye is simply the 
camera. 
Functions of Parts. The eyeballs may be likened to a 
room, with a single window in front. Just back of the 
window hangs a dark curtain with a round opening in 
it. All light entering the room must come through the 
window, pass through the opening in the curtain, and 
strike the opposite wall. The transparent cornea is the 
window; the iris is the dark curtain for regulating the 
amount of light; and the pupil is the central opening. 
The choroid is black to prevent the reflection of light 
within the-eye, and to absorb any light which may pass 
through the retina. The sclerotic is hard and firm, 
for a protection to the eye and for the attachment of 
muscles. 
The Blind Spot. All parts of the retina are not equally 
sensitive to light. One spot on it, where the optic nerve 
Fig. 104. A diagram for illustrating the existence of the blind spot. 
enters (see Fig. 103, B), is entirely insensible to light. 
This is called the blind spot: it does not interfere with 
vision because it is impossible for the light from an object 
to fall on the blind spot of both eyes at once. If certain 
rays fall on the blind spot of one eye, they will fall on 302 
THE ESSENTIALS OF HEALTH. 
a different part of the retina of the other eye. But if 
one eye be closed there is always some portion of the ob- 
ject before us which is invisible. This is easily proved 
by looking at a sharply defined object after the following 
manner: Close the left eye and look steadily at the 
small white circle to the left of Fig. 104: it is possible 
now to see the large white circle even when the eye is 
fixed on the smaller one. Hold the book vertically on 
a level with the eyes at a convenient distance. Now 
move the book slowly backward and forward. Soon a 
distance will be found where the large circle entirely 
disappears, only to reappear again as the book is moved 
nearer or farther from the eye. This is because the 
light from the large circle, when it entered the eye at 
a certain angle, fell on the retina just where the optic 
nerve enters. 
Care of the Eyes. The sense of sight is one of the 
greatest of gifts. If a man has a sound mind so that 
he is able to understand and appreciate what is brought 
to his notice, great pleasure and profit can come to him 
through the eyes alone. But great care is necessary if 
we intend to keep the eyes in their best condition. 
Many eyes are harmed, and some ruined, by their im- 
proper use during school life. The conjunctiva is easily 
inflamed from a cold or some other cause. In such 
cases a physician should always be consulted, that the 
trouble may be relieved at once before it becomes 
chronic. 
The eyes may look bright and clear, yet if their use 
in reading is followed by pain in the head, it is probable 
that there is some defect in vision. This condition 
should not be neglected, but the exact cause of the TIIE SENSE OF SIGHT. 
303 
trouble should be discovered and the proper remedy 
applied. A clear and steady light is most desirable; 
a dim light makes it necessary to put forth an effort to 
see, while a strong light is equally as injurious. Look- 
ing at a brilliant light, as the sun, is positively injurious. 
The light should come from over the shoulder, so that 
it may fall on the page of the book without coming 
directly into the face. Squinting, or looking cross-eyed, 
or rolling the eyes about, as is often done by children 
in sport, is a dangerous thing to do, as some of the 
muscles of the eyeball may be severely strained by so 
doing. 
The upright position is the natural and proper one 
for reading. Reading while lying down, especially in 
bed, is a very unwise practice. The book should be 
held from twelve to sixteen inches from the face when 
reading. Those who cannot see ordinary type, unless 
the book is nearer than ten inches, should consult an 
oculist and ascertain if it would not be best to wear 
glasses. 
The eyes should have complete rest if they are in- 
flamed, and eye-washes and ointments should not be 
used without the advice of a physician. Never rub the 
eyes, for any reason, especially if some particle of dirt 
lias fallen into them ; have all such objects carefully 
removed at once by some competent person. 
The best general advice that can be given 
As soon as the slightest failure of vision occurs, or when 
anything unusual is noticed about the eyes, do not wait 
for them to cure themselves, but seek the best medical 
aid without delay. 304 
THE ESSENTIALS OF HEALTH. 
ALCOHOL AND THE EYES. 
The bleared eyes of the hard drinker only too clearly 
show the effects of this poison on the delicate tissues of 
the eye. The blood vessels of the conjunctiva, entirely 
invisible in health, become distended to their utmost 
with blood, giving the eyes a most undesirable appearance. 
Here the cause is the same as has been previously de- 
scribed. The vaso-motor center, in the medulla, is so 
affected that the vaso-motor nerves release their control 
over the smaller arteries; the muscular walls relax; 
and the vessels become engorged with blood. If they 
remain in this condition too long they will not return 
to their former size, even if no more alcohol be taken. 
But if the habit be discontinued early, it is possible 
under proper medical treatment to restore the parts to 
health. Inflammation of the eyes is only one of the 
many serious effects of alcohol on the various organs 
and tissues of the body. In a recent treatise on diseases 
of the eye this statement occurs: “ It is a well-estab- 
lished fact that long continued and frequent indulgence 
in small quantities of spirits is very deleterious to the 
eyesight. The persistent morning nausea, muscular 
tremors, sleeplessness, and dull headaches that plague 
the chronic drinker, are likely to be associated with 
degeneration of the optic nerve tissues.” 
A very noted oculist examined the eyes of one thou- 
sand persons who were known to be addicted to the use 
of strong drink. He reported that of these one thousand 
cases, three hundred had eye affections of some kind. 
In one hundred and eighty cases the affections were of a 
severe nature. He gave it as his opinion that alcohol 
was the cause of the disease in each of these cases. THE SENSE OF SIGHT. 
305 
TOBACCO AND THE EYES. 
The edges of a smoker’s eyelids are often inflamed as 
a result of contact with the irritating smoke. Often 
the smoker experiences sharp pains in the eyeballs, 
with slight failure of vision. 
The most serious results to the eyes sometimes follow 
the use of tobacco; one of these is known as “ smokers’ 
blindness.” The most careful examinations of the eye 
fail to discover any change in its structure, yet gradually 
the vision becomes less and less until complete blindness 
results. We have the testimony of a number of eminent 
oculists to the effect that persistent smoking by the 
young causes frequent and severe affections of the eyes. 
QUESTIONS. 
1. How are the eyes protected ? 
2. Describe the eyelids. 
3. What membrane lines them? 
4. Of what use are the eyelids? 
5. What is the object of the oil glands? 
6. Where are the lachrymal glands? 
7. What outlet is provided for the lachrymal fluid? 
8. How many membranes surround the eyeball? 
9. Name the posterior part of the outer membrane. The an- 
terior part. 
10. Where is the choroid? The iris? The pupil? 
11. What is the inner coat of the eye called? 
12. With what is the retina connected? 
13. Why is the choroid black? Why is the sclerotic hard? 
14. Where is the blind spot of the eye ? 
15. Look at Fig. 104, as suggested on page 302. 306 
THE ESSENTIALS OF HEALTH. 
CHAPTER XXX. 
THE SENSES OF TASTE AND SMELL. 
The Tongue. The sense of taste is located in the 
tongue, the back part of the roof of the mouth, and, 
to a slight extent, in the sides of the throat. The 
mucous membrane of the tongue, however, is more 
especially the seat of this sense. The tongue is com- 
posed of voluntary muscle, covered with mucous mem- 
brane. In health, it is moist and of a light-red color. 
Any marked change from this condition is an indication 
of some departure from health. Thus the appearance 
of the tongue often gives aid to the physician in ascer- 
taining the source and character of the disease. 
Papillae of the Tongue. The mucous membrane of 
the tongue is covered with a great number of papillae. 
In these papillae are found blood vessels, nerves, glands, 
and “ taste buds.” There are three varieties of papillae 
on the surface of the tongue. The largest papillae can 
be seen by the unaided eye ; they are far back at the 
base of the tongue, arranged in the form of the letter 
Y, with the point of the Y toward the back. There are 
eight or ten of these, each consisting of a central pa- 
pilla surrounded by a wall. The second variety can 
also be seen with the unaided eye, scattered freely over 
the surface of the tongue. These papillae are easily THE SENSES OF TASTE AND SMELL. 
307 
recognized by their deep-red color, and because they are 
larger than the third variety. They are most abundant 
at the tip of the tongue, where they present a club-shaped 
Fig. 105. The tongue, showing the varieties of papillae. 
appearance. The third variety is the most numerous 
of all. The papillae are minute in size and are evenly dis- 
tributed over the surface of the tongue. They are of a 
whitish color, owing to their thick epithelial covering. 308 
THE ESSENTIALS OF HEALTH. 
In some of the papillae are found loops, or coils, of 
minute blood vessels; in others there is the ending of a 
nerve fiber, giving the sense of touch to the tongue ; 
while in the other papillae are minute bodies, especially 
for the sense of taste. 
The Taste Buds. I lie taste buds are found in the 
large papillae at the base of the tongue ; and a few are 
also distributed to 
other papillae. They 
are collections of 
cells arranged in the 
form of buds, hence 
called taste buds. 
Each bud is not over 
of an inch in 
length. The loca- 
tion of these bodies, 
in the edges of the papillae, is illustrated in Fig. 106. It 
is seen that they are situated in the folds between the 
papillae, rather than 
on the upper free 
surface. Fig. 107 
shows some of these 
bodies more highly 
magnified. Some 
of the cells compos- 
ing each bud are 
directly connected 
with a nerve fiber so that whenever anything comes in 
contact with these cells an impression of its “ taste ” 
is conveyed down the cells and along the nerve fibers to 
the brain. 
Fig. 106., A section through two papilla? 
of the tongue, showing the taste buds, at A, 
magnified. 
Fig. 107. Three of the taste buds of Fig. 
106, highly magnified. THE SENSES OF TASTE AND SMELL. 
The Sense of Taste. There are four different qualities 
of taste. We have the sensations of sweet, bitter, acid, 
and saline. In order that any of these may be appre- 
ciated, the substance must be dissolved. Dry sugar 
placed on a perfectly dry tongue produces no sensation 
of sweetness. Some of it must be dissolved before any 
effect is produced on the cells of the taste buds. The 
saliva aids in this, although there are mucous and se- 
rous glands in the tongue which secrete a watery fluid. 
The movements of the tongue promote the flow of these 
secretions, and thus aid in dissolving the substances and 
in distributing them over a greater surface. The sense 
of taste can be greatly improved by practice, while it is 
materially aided by the sense of smell. 
Confusion of Taste and Smell. The senses of smell 
and taste are often confused. Many times we believe 
we taste a substance when it is only the odor which is 
perceived. It is stated that neither vanilla nor garlic 
has any taste; it is their odor alone which is noticed. 
The odor of a drug is often more disagreeable than its 
taste; for this reason many medicines are best taken 
after first closing the nose and thus shutting off the odor. 
A severe cold is said to affect the sense of taste; this is 
because the lining membrane of the nose is inflamed, 
and we are unable to distinguish odors. In man the 
sense of taste is more highly developed than that of 
smell, while in some of the lower animals, as the dog, 
the sense of smell is the more acute. 
Taste Easily Changed. The taste of many substances 
which were at first very pleasant may become disagree- 
able because of too frequent use, or of unpleasant asso- 
ciations ; many articles of food are distasteful when 310 
THE ESSENTIALS OF HEALTH. 
first used, but after a time they are greatly desired. 
Many persons have had to make repeated trials before 
becoming fond of oysters, tomatoes, or olives; they began 
by using a small amount and then gradually educated 
their sense of taste, until a fondness for them was ac 
quired. Habit has much to do with this; we like and 
dislike those things which we are in the habit of seeing 
other members of the family like and dislike. Disease 
often perverts the taste, so that persons will drink vine- 
gar, and eat chalk and plaster. 
Impressions of Taste Remain. If a very sweet or a very 
bitter substance be placed in the mouth and then removed 
from it, the taste is retained for some time. Therefore, 
if one substance be tasted and then quickly followed by 
others of different tastes the impressions will be confused. 
If the taste of the first was well marked it may impart its 
qualities to those following. Therefore, to take a medi- 
cine which has a disagreeable odor and taste, first take 
into the mouth some strongly flavored substance; hold 
the nose, to shut out the odor, and then swallow the 
dose. In this manner, for reasons already given, there 
will be little recognition of the drug. Young persons 
often form the habit of eating cloves and other spices: 
this is very harmful, not only because it is likely to in- 
jure the sense of taste, but also because it seriously dis- 
turbs the action of the stomach. 
Tobacco and Taste. Tobacco blunts the sense of taste. 
This is exactly what we should expect, for the papillae of 
the tongue become saturated with the tobacco flavor, and 
the taste buds are impaired by their contact with the 
poisonous properties of the nicotine. The taste of to- 
bacco is continuously in the mouth, and in order to TIIE SENSES OF TASTE AND SMELL 
311 
taste other substances, they must he highly spiced; 
this leads to disorders of the stomach as already 
described. 
The Nose. The sense of smell is 
located in the nose. The two open- 
ings which lead into the nose are 
called the nostrils. They are sur 
rounded by a number of fine hairs, 
which aid in keeping foreign bodies 
from entering the nasal cavities. 
The framework of the nose con- 
sists of bone and cartilage. A thin 
wall, called the septum, divides the 
interior into two cavities; these 
are irregular in shape and extend 
from the nostrils, in front, to the 
upper part of the pharynx, behind. 
Fig. 108. Transverse 
section of the framework 
of the nose : (1) the nasal 
cavities. On the outside 
of each cavity are the 
curved turbinated hones ; 
(2) the hones forming the 
roof of the mouth and the 
floor of the nasal cavities. 
The black represents the 
bone, the lighter shade 
represents the mucous 
membrane covering the 
bone. 
The inside of each, or 
the side toward the 
median line, is smooth, 
because the septum it- 
self is smooth ; but the 
outside is most irregu- 
lar, owing to the pres- 
ence of three curved 
or scroll-like bones, 
called the turbinated bones. These are well shown, as 
viewed from the side, in Fig. 109. Lining each nasal 
Fig. 109. The outside of the left nasal 
cavity, showing the three turbinated bone. 312 
THE ESSENTIALS OF HEALTH. 
cavity is a mucous membrane, which is especially thick 
over the turbinated bones. 
The Olfactory Nerve. Ihe nerve of smell is called the 
olfactory nerve. It arises from the lower and front part 
of the brain, and passes down tlirough minute openings 
in the skull just beneath it. Its line fibers are distrib- 
uted to the upper half of the mucous lining of the 
nose; therefore only this part of the nasal cavity has 
the sense of smell. The lower half is endowed with 
ordinary sensibility so 
that, when irritated in 
any way, it causes the 
reflex act of sneezing. 
The Sense of Smell. We 
know little about the 
action of odorous bodies ; 
we cannot see an odor, 
neither can it be meas- 
ured. Musk lias been 
placed in an open dish in 
a room for many months, 
during which time it was 
constantly giving off a 
powerful odor, yet its 
weight was not d iminished 
during the entire time. 
We simply know that certain substances give off a gas- 
eous or vaporous material; that this material pervades 
the surrounding atmosphere; and that it is often in- 
haled with the inspired air. We know further, that it 
may produce a peculiar effect on the olfactory nerve, 
ffivins: us the sense of smell. 
Fig. 110. The right nasal cavity, 
showing the termination of the olfac- 
tory nerve : T, the turbinated bones, 
as represented in Fig. 109; o, the 
olfactory bulb, lying beneath the front 
part of the cerebrum, c; B, the bony 
floor on which rests the cerebrum. THE SENSES OF TASTE AND SMELL. 
Conditions Affecting this Sense. In order to appre- 
ciate the odor of a substance, it must be brought to 
the olfactory nerve in a gaseous or vaporous condition. 
Solid or liquid bodies, in the nose, do not produce any 
sense of smell. This is easily proved by filling the nose 
with rose water; after so doing, no odor of the rose is 
perceived. 
The continued influence of an odor blunts the acute- 
ness of smell. This is illustrated in every-day life. 
Upon first entering a room we may notice the odor of 
escaping gas, while in a short time we become uncon- 
scious of its presence ; we notice that a room is “ close ” 
only when we first enter it. In all such cases the first 
impressions should be the guide. Some persons are ex- 
tremely susceptible to odors of all kinds; they not only 
detect the least pleasant or unpleasant odors, but they 
are often made ill by them. In some people the inhala- 
tion of certain powders excites violent inflammation of 
the nasal passages. 
The sense of smell may be greatly developed. It is 
related of a certain boy named James Mitchell, who was 
horn deaf, dumb, and blind, that he could accurately 
identify many objects, simply by the sense of smell. 
Repeated and short contacts of an odor with the nasal 
mucous membrane favor the development of the sen- 
sation. It appears that the odor impresses the olfac- 
tory nerve at the first moment of contact. Therefore 
repeated sniffings, or rapid inspirations through the 
nose, give a more exact impression of the odor. If sub- 
stances of different odors be placed near the nostrils, 
they will not be confused, but first one odor and then 
the other will be perceived. 314 
THE ESSENTIALS OF HEALTH. 
Use of Sense of Smell. The sense of smell is of use 
in many ways : it aids in the choice of foods, for, as a 
rule, food which has a tainted odor is unfit for use; and 
it aids in the detection of impurities in the air. It is 
placed at the very entrance of the air into the body to 
give warning of approaching danger. It is true that 
this sense does not warn us of the poisonous agents in 
the air which cause the contagious diseases, yet it does 
give notice of offensive vapors which are dangerous to 
inhale. Vapors which are irritating to the nose would 
be much more so to the more delicate tissues of the 
lungs. It is safe to say that in the majority of cases, 
disagreeable odors mean dangerous odors. 
Often Highly Developed. In some of the lower ani- 
mals the sense of smell is developed to a marvelous 
degree. The capabilities of the dog are none the less 
wonderful because so commonly observed. Nearly every 
one can tell some wonderful stories of this animal, 
where the power to detect obscure odors is concerned. 
We all know how he will return home after having been 
taken away long distances; how he will follow many 
feet behind his master through crowded streets and 
into crowded halls; how he will recognize clothing; 
and how he will follow the trail of the fox for many 
miles. Other animals, as the lion, can tell of the ap- 
proach of man, or if any prey be near ; while the deer 
can detect “ in the air ” the approach of an enemy when 
a great distance away. 
Catarrh. Catarrh is usually the result of repeated in- 
flammation of the mucous membrane of the nose. As a 
result the tissues are swollen and thickened, so that it is 
very difficult to breath through the nose. This makes it THE SENSE OF TASTE AND SMELL. 
315 
necessary to breathe through the mouth, which is a great 
source of throat trouble. Catarrh also results from de- 
formed bones of the nose. The septum is bent over to 
one side, nearly or completely closing that nasal cavity. 
This may necessitate breathing through the mouth. The 
great majority of cases of catarrh can be cured by proper 
treatment. 
QUESTIONS. 
1. Give a general description of the tongue. 
2. How many varieties of papillae on it ? 
3. What are found in these papillae? 
4. Where are the taste buds found? What are they? 
5. What varieties or qualities in the sensation of taste? 
6. Why cannot dry substances be tasted? 
7. What fluids aid in dissolving the substances to be tasted? 
8. illustrate how the sensations of taste and smell are often 
confused. 
9. Do impressions of taste remain ? Illustrate. 
10. How does tobacco affect the taste? 
11. Where are the turbinated bones ? 
12. What is the name of the nerve of smell ? 
13. What part of the nasal cavity is endowed with the sense of 
smell ? 
14 Is much known about the action of odorous bodies? 
15. State some of the things known. 
16. Give some of the conditions affecting the sense of smell. 
17. How is this sense useful to us? 
18. Give some illustrations showing how highly it may be de- 
veloped. 316 
THE ESSENTIALS OF HEALTH. 
CHAPTER XXXT. 
THE SENSE OF HEARING-. 
The Organ of Hearing. The organ of hearing consists 
of three parts : the external ear ; the middle ear; and 
the internal ear. The vibrations of the air are collected 
by the external ear, received by the middle ear, and 
transmitted through its bones to the inner ear. The 
inner ear contains the termination of the nerve of hear- 
ing, or the auditory nerve. 
The External Ear. The external ear consists of a 
framework of cartilage which is loosely attached to the 
bones of the head and to the auditory canal. The ear can 
be slightly moved by the action of certain muscles, al- 
though in man this is barely perceptible. In the lower 
animals the movements are very extensive. The ear is 
quickly changed from one position to another to better 
catch the sound coming from any quarter. In these 
animals the ears aid greatly in giving expression. 
The auditory canal is about an inch or an inch and a 
quarter in length, and extends from the external open- 
ing to the middle ear. Near the orifice are a number of 
fine hairs, and farther in are the openings of glands 
which secrete the earwax. Both the hairs and wax are 
for the protection of the ear, keeping out small insects, 
dust, and other foreign bodies. THE SENSE OF HEARING. 
317 
The Middle Ear. The middle ear, or tympanum, is an 
irregular shaped cavity about one half an inch in length, 
and one fourth an inch from side to side. It is called “ the 
drum of the ear,” because it contains air and has a thin 
membrane over one part of it which is easily affected by 
wave sounds. The middle ear, or the drum, is sepa- 
rated from the auditory canal by a thin membrane, 
Fig. 111. The ear : c, the auditory canal, that leads to the middle 
ear ; to, the -middle ear, or drum. The tympanic membrane is the curved 
white line to the left of the letter m; i, the inner ear; n, the auditory 
nerve going to the brain ; T, the Eustachian tube, leading from the middle 
ear to the upper part of the pharynx. 
called the tympanic membrane ; this is often called the 
“ drum,” but incorrectly so, as it is oidy the thin mem- 
brane over the head of the drum; it is elastic, and so 
thin that it is nearly transparent. A study of Fig. Ill 
will aid in locating the parts already mentioned. The 
external ear with the auditory canal, C, is very evident. 
The middle ear, M, is separated from the outer ear, by 
a curved white line which represents the tympanic 318 
THE ESSENTIALS OF HEALTH. 
membrane. Directly above the letter M, are three mi- 
nute bones described below; the one at the left resembles 
a hammer; the middle one, an anvil; and the one at the 
right, a stirrup. A tube extends from the middle ear to 
the throat. At the right of the middle ear is the inner 
ear, at I; it is most complicated in its structure, and is 
separated from the middle ear by a thin membrane 
against which the stirrup bone rests. 
The tympanic membrane is often diseased from in- 
flammation of the middle ear. Not infrequently it has 
minute openings through it, while sometimes it is nearly 
all destroyed. It is the function of the tympanic mem- 
brane to catch the sounds entering the external ear. 
As they strike the membrane, they cause it to vibrate, 
and these excite a corresponding vibration in the parts 
beyond. 
Bones of the Middle Ear. In the middle ear are three 
bones, so minute that all together they weigh but a few 
grains. Yet they 
give attachment to 
minute muscles, 
have movable joints, 
and perform most 
important work. 
They very much re- 
semble three well 
known articles; 
hence they are called 
the malleus, or ham- 
mer ; the incus, or anvil; and the stapes, or stirrup. The 
tympanic membrane is attached to the handle of the 
hammer; the hammer, to the anvil; and the anvil, to 
Fig. 112. Tlie three hones of the middle 
ear : h, the hammer, or malleus; a, the an- 
vil, or incus; s, the stirrup, or stapes. THE SENSE OF HEARING. 
319 
the stirrup ; thus a chain of bones is established from 
the tympanic membrane across the cavity of the middle 
ear. The outer end of this bony chain is attached to a 
membrane, and so is the inner end. Beneath the inner 
membrane, just opposite the stirrup, in the inner ear, is 
Fig. 113. The middle and inner ears, from a different view and on a 
larger scale than Fig. 111. A, the auditory canal of the outer ear; T, the 
tympanic membrane; Mm, the middle ear; E, the Eustachian tube; 
I i, the inner ear, surrounded by bone; s, the stapes; I, the incus; M, the 
malleus. 
a fluid. Therefore the vibrations of the air at last come 
to affect this fluid in the inner ear. A reference to 
Fig. 113 will make this clear; the sound enters the 
external ear and passes down the auditory canal, A, and 
strikes against the tympanic membrane, T, throwing 
it into vibrations ; these vibrations are communicated to 
the handle of the hammer, M ; thence to the anvil, I; 
thence to the stirrup, S ; and thence to the membrane to 
which the stirrup is attached. As this membrane vi- 
brates it throws a fluid beyond "it into corresponding 
vibrations; and these so affect the endings of the audi- 
tory nerve that we have at last the sensation of hearing. 320 
T11E ESSENTIALS OF HEALTH. 
The Eustachian Tube. The middle ear is not a closed 
cavity. It communicates with the pharynx by means of 
a passage, called the Eustachian tube. The tube and 
the middle ear are lined with a mucous membrane, and 
the former opens into the upper part and on the side 
of the pharynx directly behind the opening of the lower 
part of each nasal cavity. The object of this tube 
is to keep the air in the middle ear of the same 
density as that outside the ear. In the healthy ear, 
therefore, the air in the external ear and that in the 
middle ear are of the same density, with only a thin vi- 
brating membrane between. 
The Eustachian tube is ordinarily closed, opening only 
during the act of swallowing, and thus allowing the 
passage of air to the middle ear. It is often closed, as 
a result of chronic catarrhal affections, so that it does 
not open for the passage of air through it; this condi- 
tion is one of the causes of deafness; but it is often 
possible to relieve such cases by the use of instruments 
with which air niay be forced through the tube into the 
middle ear. 
The Internal Ear. The internal ear is the most essen- 
tial part of the organ of hearing, for it contains the 
terminal fibers of the auditory nerve. Its parts are 
deeply seated in the bones of the skull and are most 
intricate and complicated in structure. 
The Sense of Equilibrium. A certain portion of the 
inner ear consists of three bony tubes, called the semi- 
circular canal. When these canals are injured in the 
lower animals it is found that the animal rolls its head 
from side to side, up and down, while all its movements 
are irregular. It appears to be unable to direct its THE SENSE OF HEARING. 
321 
movements ; for a bird thus injured will experience great 
difficulty in walking to the food placed near, and in pick- 
ing it up. The animal sees well and appears to hear well, 
but it reels and falls, acting as if it were dizzy. From 
these observations and from some made on man, it is 
believed that the semi-circular canals contain nerves 
which enable the body to maintain its proper poise, or 
balance, a condition just opposite that of being dizzy. 
It is probable that this function residing in the middle 
ear is connected with the similar function of the 
cerebellum. 
Care of the Ears. One of the most common causes 
of injury to the ears is the introduction of pins, or other 
hard substances, into the auditory canal for removing 
the earwax. The ordinary washing and wiping with a 
towel is sufficient to insure perfect cleanliness, while 
the constant introduction of hard substances is likely 
to set up an irritation which may eventually impair the 
hearing. Currents of cold air blowing into the ears 
may do great harm by chilling the sensitive tympanic 
membrane. The contact of cold water with this mem- 
brane often causes the earache, or acute inflammation 
of the middle ear; for this reason it is always better 
to place pieces of cotton in the ears before diving, or 
bathing in the surf. 
Foreign bodies in the ear are not always easily re- 
moved. Insects are best removed by having warm sweet 
oil gently poured into the auditory canal; this will either 
drive the insect out or kill it; probably both. Physi- 
cians should always be consulted for the removal of 
other foreign bodies. The firing of a cannon has caused 
deafness to those standing near. Boxing the ears is 322 
THE ESSENTIALS OF HEALTH. 
especially dangerous ; the sudden forcing the air into the 
ear may rupture the tympanic membrane and seriously 
impair the hearing. 
The value of acute hearing to the child cannot be over- 
estimated ; it bears a more important relation to the 
intellectual development than the eye itself. This is 
proved by the fact that children born blind often ex- 
hibit remarkable faculties of the mind; while generally 
the mental deficiencies of those born without hearing are 
very marked. The hearing can be greatly developed by 
training. The acute ear of the uneducated Indian will 
detect the approach of moving bodies long before the 
untrained ear is made aware of their approach ; and the 
skilled musician can detect the most delicate variation 
from the proper sound of a note. 
QUESTIONS. 
1. Name the parts composing the organ of hearing. 
2. Describe the auditory canal. 
3. Why is the middle ear called the drum of the ear? 
4. Where is the tympanic membrane located? 
5. Give the names of the bones of the middle ear. 
6. Describe the effects produced by sound entering the ex- 
ternal ear. 
7. What is the object of the Eustachian tube? 
8. Its closure often causes what ? 
9. Where is the internal ear situated ? 
10. What is the function of the semicircular canals? THE SENSE OF TOUCH. 
323 
CHAPTER XXXII. 
THE SENSES OF TOUCH: TEMPERATURE: 
WEIGHT: PRESSURE: COMMON SEN- 
SATION: AND PAIN. 
The Sense of Touch. A reference to the chapter on 
the skin will recall the fact that in some of the papillae 
of the skin are nerve fibers; in Fig. 92, at 4, is such a 
nerve termination. These papillae are called the touch 
corpuscles, as they are especially concerned in the sense 
of touch. It must be remembered, as shown in Fig. 92, 
that there is only a thin layer of cells between these 
corpuscles and the surface of the skin ; therefore it is 
readily understood that any impression made on the 
outer surface of the skin is almost in direct contact 
with one of these touch corpuscles. 
The touch corpuscles are very numerous on the palms 
of the hands and palmar surfaces of the fingers, while 
they are the least numerous on the back. The sense of 
touch seems most acute on the tip of the tongue. It is 
the least complicated of any of the senses and is the one 
first developed in the child. It is in constant use, bring- 
ing us into the closest relations with external objects. 
By its use, we learn the size, figure, solidity, and smooth- 
ness, as well as many other qualities of bodies. 
The sense of touch is capable of being highly devel- 
oped, especially if great reliance has to be placed upon 324 
THE ESSENTIALS OF HEALTH. 
it; it is developed to the greatest degree in the blind. 
They soon learn to read by passing the fingers over 
raised letters; to recognize persons by feeling their 
faces; to distinguish plants by touching them ; and to 
become expert musicians. The blind sculptor Gonelli 
is said to have modeled beautifully, relying on the sense 
of touch alone. 
This sense is very accurate, and less liable to deceive 
than the other senses. The eye and ear often convey 
to us vague and many times wrong impressions ; but the 
touch at once corrects these and gives us the true condi- 
tion. This is well illustrated in cases where persons who 
were born blind have had their sight restored by some 
surgical operation. They could not tell a globe from a 
round card, nor a cube from a square, nor a disk from 
a circle ; but as soon as the hands were placed on these 
bodies the errors were immediately discovered. 
Degrees of Acuteness of Touch. Those parts are most 
sensitive to touch which have the greatest number of 
touch corpuscles. The .degrees of delicacy are measured 
by means of a pair of compasses with blunted points. 
The two points are touched at the same moment to the 
skin, while the eyes are closed; they are gradually 
brought nearer together until both points are felt as 
one, when their distance apart is noted. The same 
experiment can be performed, though less accurately, 
with pins. Two pins are held with their points at least 
an inch apart, and then pressed lightly against the 
skin on the back of the wrist of another person. Repeat 
the experiment, bringing the points nearer together each 
time. Soon the person will declare that he feels but 
one point instead of two. The distance between the THE SENSES OF WEIGHT AND PRESSURE. 
325 
points will give the degree of acuteness of touch for 
that part of the body. In this way it has been proved 
that the shortest distance at which the two points of a 
compass can be distinguished as double is as follows: 
on the tip of the tongue of an inch; on the inside 
of the tips of the fingers of an inch; on the palm of 
the hand about of an inch; on the cheek about | of an 
inch ; and on the back over 2 inches. 
Touch in the Lower Animals. All forms of animal 
life appear to have this sense developed to a greater or 
less degree. In the cat there are special organs endowed 
with unusual sensitiveness ; these are called the whiskers. 
The long hair of the cat and other animals renders the 
general surface of the skin little adapted for the sense 
of touch; hence, they have been provided with a few 
long hairs, called feelers, which are in close connection 
with nerve fibers in the skin. The touch is extremely 
sensitive in the trunk of the elephant; while many 
small insects have special organs, or feelers, for this 
sense. 
The Sense of Temperature. The temperature sense 
makes us acquainted with all the variations in the 
temperature of the skin. The skin has a proper tem- 
perature of its own and when this is maintained we are 
unconscious of either heat or cold; but if any part of 
the skin rises above its proper temperature we feel 
warm, and if it falls below it we feel cold. When a 
body is applied to the skin which takes heat from it a 
sensation of cold is produced; while if a body imparts 
heat, warmth is experienced. The sense of temperature 
appears to be principally in the skin, the mouth, the 
throat, and at the entrance of the nose. The apprecia- 326 
THE ESSENTIALS OF HEALTH. 
tion of temperature varies for the different parts of the 
body, as for instance, hot applications which would be 
intolerable on the face can be borne when applied to the 
scalp. 
The sensations of heat and cold are sometimes strangely 
confused. If the hand be dipped in very cold water, and 
then dipped again in water a number of degrees warmer, 
there is first a feeling of warmth and then of cold; if 
one finger be dipped in warm water, the feeling of 
warmth will not be nearly so great as it would if the 
whole hand were immersed ; if two equal weights be 
lifted in the hands, one warm and the other cold, the 
latter will be declared to be heavier. 
The Sense of Weight. This is also known as the 
muscular sense. It informs us of the amount of mus- 
cular contraction necessary to lift a body; while it de- 
pends partly on the sense of pressure and partly on 
common sensibility. It is, therefore, about midway be- 
tween a special sense and the common sensation of the 
body. By placing weights in each hand and then rais- 
ing and lowering the one becomes conscious of 
a certain amount of resistance. The muscular exertion 
required to lift the body gives us the sense of weight; 
and by practice it is possible to distinguish very slight 
differences in the weights of bodies, even of those as light 
as coins. 
The Sense of Pressure. The sense of pressure enables 
us to judge of the amount of weight or pressure, on 
different parts of the skin. To illustrate this, the hand, 
or the part being tested, must rest on the table, or must 
be supported in some way. The various parts of the 
body differ exceedingly as to the amount of weight re- PAIN. 
327 
quired to make itself felt: the most acute portion is 
the forehead ; next, the temples; then the back of the 
head; and lastly, the forearm. 
Common Sensation. The term “ common sensation ” 
refers to all parts of the body, which have sensitive 
nerves that are capable of causing pleasant or unpleasant 
sensations. These cannot be compared to the special 
senses already described ; in fact, they are difficult to 
describe at all. We have many of these common sen- 
sations, each one of a character peculiarly its own; thus 
we speak of the sensations of hunger, of thirst, of pain, 
of fright, of fatigue, of illness, and of health. 
Pain. If any of the nerves of sensation be disturbed 
it produces a sensation called pain. If a sensitive nerve 
be cut in any part of its course it produces pain which is 
always referred to the place where the nerve ends, rather 
than to the point injured. Thus, touching the ulnar 
nerve, the “ crazy bone ” at the elbow, causes a pain in 
the little finger and part of the adjoining finger; these 
are the parts in which the nerve terminates. After 
amputation of limbs, it often occurs that one of the 
severed nerves gives rise to pain; in this case the 
afflicted person says he feels the pain in the ampu- 
tated fingers or toes. It is not known what causes 
the varieties of pain; for some are sharp and cutting, 
while others are dull and throbbing. 
Dreadful as it is, still pain is a valuable bodyguard. 
It tells of the approach of danger, and points to disease 
when it is present. It may be stated that any so-called 
stimulus will cause pain if applied beyond the normal 
limit and to an excessive degree. Light is the stimulus 
for vision; yet strong light, as the glare of the sun, is 328 
THE ESSENTIALS OF HEALTH. 
at once painful. Sounds falling on the ear may awake 
the most pleasant memories ; yet loud and long con- 
tinued sounds soon become positively painful. The 
ordinary contraction of a muscle is free from pain; yet 
the rapid and violent muscular contractions in spasms 
are intensely painful. 
The nerves of sensation are the great protectors of 
the body. Without them and their accompanying pain 
we should cut, burn, bruise, and otherwise disfigure the 
body in many ways as we go about our daily work. 
Fain keeps us from pursuing many harmful courses, 
and thus aids greatly in protecting the body. It is an 
unaccountable fact that some persons suffer more pain 
than others who have the same diseases or injuries; so 
it follows that the severity of the suffering does not al- 
ways indicate a corresponding intensity of the disease 
or injury. 
Animals appear to suffer pain, especially those ani- 
mals which are most noted for their intelligence, as the 
dog and the horse. The finer bred the animal, so much 
the more susceptible is it to pain. The thoroughbred 
and blooded horse appears to suffer great pain, while the 
ordinary work-horse may be. perfectly indifferent. But 
those creatures low in the scale of animal life do not ex- 
hibit evidence that they suffer much pain. ADDITIONAL TESTIMONY. 
329 
CHAPTER XXXIII. 
ADDITIONAL TESTIMONY AGAINST 
ALCOHOL AND TOBACCO. 
From the Medical Profession. In Canada the medical 
profession is awake to the growing evils of intemper- 
ance. In the city of Montreal, twenty-five professors in 
medical colleges, and over seventy physicians of the city, 
united in the following declaration against alcohol: — 
“ We, the undersigned members of the medical profession in 
Montreal, are of opinion — 
“ 1. That a large proportion of human misery, poverty, dis- 
ease, and crime is produced by the use of alcoholic liquors as 
a beverage. 
“ 2. That total abstinence from intoxicating liquors, whether 
fermented or distilled, is consistent with, and conducive to, the 
highest degree of physical and mental health and vigor. 
“ 3. That abstinence from intoxicating liquors would greatly 
promote the health, morality, and happiness of the people.” 
In the cities of New York and Brooklyn, many of the 
most prominent and influential members of the medical 
profession unhesitatingly declare against the use of alco- 
holic beverages. Notice the strong language in the fol- 
lowing declaration: — 330 
THE ESSENTIALS OF HEALTH. 
“ 1. In view of the alarming prevalence and ill effects of in- 
temperance, with which none are so familiar as members of 
the medical profession, and which have called forth from emi- 
nent English physicians the voice of warning to the people of 
Great Britain concerning the use of alcoholic beverages, we, 
the undersigned members of the medical profession of New 
York and vicinity, unite in the declaration that we believe 
alcohol should be classed with other powerful drugs ; that when 
prescribed medicinally it should be with conscientious caution 
and a sense of grave responsibility. 
“2. We are of opinion that the use of alcoholic liquor as a 
beverage is productive of a large amount of physical disease; 
that it entails diseased appetites upon offspring; and that it is 
the cause of a large percentage of the crime and pauperism of 
our cities and country. 
“ 3. We would welcome any judicious and effective legislation, 
State and national, which should seek to confine the traffic in 
alcohol to the legitimate purposes of medical and other sciences, 
art, and mechanism.” 
This paper was signed by over one hundred of the 
leading physicians of New York and Brooklyn. Among 
the names we find many that are familiar to the medical 
profession of the whole world, and some that are known 
wherever the subject of public health is discussed. A 
large number of the signers is composed of men who 
have taught five years in medical colleges, practised in 
large hospitals, and been actively engaged as members 
of Boards of Charity and Public Health Associations. As 
teachers they have become acquainted with the scientific 
side of the question, and as practitioners they have be- 
come familiar with the practical results of the use of 
strong drink. No men are better qualified to judge of 
the evils of strong drink than those of the medical pro- ADDITIONAL TESTIMONY. 
331 
fession, and the declarations of these men is against the 
use of alcoholic liquors as a beverage. 
Alcohol is a Poison. Dr. E. W. Lambert, the medical 
director of the Equitable Life Insurance Company, 
writes to a prominent member of the United States 
Senate as follows : — 
“ To speak chemically, alcohol is a concentrated hydrocarbon, 
and needs a great deal of physical labor to dispose of it in the 
animal economy. I have noticed that men who are given to 
the daily use of alcohol degenerate faster than those who ab- 
stain from its use. They are more liable not only to chronic 
degenerations (such as fatty livers, fatty kidneys, and the like), 
but they are also more liable to be attacked by acute diseases; 
and acute diseases are much more likely to prove fatal to the 
users of alcohol than to those who do not use it. 
“Take for illustration a young friend of mine, who com- 
menced the use of alcohol about the age of twenty-one years. 
He died after two days’ illness. When I came to examine his 
body after his death, I found that all his internal organs be- 
longed to a man of the age of seventy years, and not to a man 
of forty, the age at which he died. I have noticed that steady 
users of alcohol are very much more apt to die between the 
ages of forty and fifty years of some acute disease than those 
who do not use it as a beverage. 
“ I have said nothing as yet concerning the danger which 
every one undergoes who uses alcohol regularly. ... If he 
once gets the appetite, there is nothing on the earth, or above 
it, or under it, that he will not do in order to gratify this mor- 
bid appetite. He will lie or steal, or see his family go to ruin 
with perfect equanimity, provided he can satisfy this inordinate 
craving for alcohol.” 
Dr. Dods, of England, said before a committee of the. 
House of Commons : — 332 
THE ESSENTIALS OF HEALTH. 
“ Writers on Medical Jurisprudence rank alcohol among 
narcotico-acrid poisons, of which small quantities, if repeated, 
always prove more or less injurious, and agree that the mor- 
bid appearances seen after death occasioned by ardent spirits 
exactly agrees with those that result from poisoning caused by 
any other substance of the same class.” 
Medical men are familiar with the physiologies of the 
renowned Dr. W. B. Carpenter, of London. His works 
on mental physiology have made him rank high as a 
philosopher; while his exhaustive treatises on micros- 
copy illustrate how closely he observes even the minutest 
things. Dr. Carpenter concludes liis observations on the 
subject of alcohol as follows : — 
“The introduction of alcohol into healthy blood can do 
nothing but mischief; no one who is familiar with the action 
of poisons upon the living animal body, and has made the 
nature of that action a special study, has the smallest hesitation 
in saying that alcohol is a poison.” 
Alcohol is of no Use. Dr. William Pepper, of the 
University of Pennsylvania, is another author of great 
prominence. His exhaustive work on the Practice of 
Medicine has made for him an enduring narrie as a 
profound scholar and keen observer. He testifies as 
follows: — 
“ One of the worst features of the action of alcohol in a 
large majority of young persons is that, though taken in small 
amount, and even in the form of light wines or beer, its first 
agreeable effect is followed by a feeling of lassitude and depres- 
sion, readily mistaken for debility, and suggesting a repetition 
of the stimulant. But these unpleasant feelings are the direct 
result of the presence in the blood and tissues of poisonous mat- 
ters, coming from the imperfect digestion of the alcohol, or of ADDITIONAL TESTIMONY. 
333 
food with whose complete assimilation the dose of alcohol has 
interfered. The habitual use of alcoholic beverages by healthy 
persons is highly injurious, and involves the risk of develop- 
ing serious disease. I am, indeed, satisfied that all persons in 
good health are better without alcohol, in any form or in any 
amount, as a beverage.” 
From the hundreds of opinions of individual medical 
men we select the following as illustrating the fact that 
scholarship and experience alike condemn the use of 
strong drink. Dr. N. S. Davis, of Chicago, takes the 
most advanced ground, going so far as to state that 
alcohol is not even desirable as a medicine. Dr. Davis 
is not only most skilled in his profession, but is also a 
man of great general learning. He has been honored 
with the highest gifts in the power of the profession to 
bestow upon him, while his opinion is acknowledged by 
all to be of the greatest weight. To what does this emi- 
nent scholar testify ? — 
“ I have been constantly engaged in the practice of medi- 
cine a little more than fifty years, embracing both private and 
public hospital practice, and have demonstrated by the last 
forty years of actual experience that no form of alcoholic 
drink, either fermented or distilled, is necessary or desirable 
for internal use in either health or in any of the varied forms 
of disease; but that health can be better preserved and disease 
be more successfully treated without any use of such drinks. 
And while it is true that during the last thirty years I have 
not prescribed for internal use the aggregate amount of one 
quart of any kind of fermented or distilled drinks, either in 
private or hospital practice, yet I have continued to have abun- 
dant opportunities for observing the effects of these agents as 
given by others with whom I have been in council; and simple 334 
THE ESSENTIALS OF HEALTH. 
truth compels me to say that I have never yet seen a case in 
which the use of alcoholic drinks either increased the force of 
the heart’s action or strengthened the patient beyond the first 
thirty minutes after it was swallowed.” 
Alcohol Shortens Life. The President of the Connec- 
ticut Mutual Life Insurance Company has given the 
following testimony: — 
“Among the persons selected with care for physical sound- 
ness and sobriety, and who are, as a rule, respectable and 
useful members of society, the death-rate is more profoundly 
affected by the use of intoxicating drinks than from any other 
one cause, apart from hereditary. 
“I protest against the notion so prevalent and so industri- 
ously urged that beer is harmless, and a desirable substitute 
for the more concentrated liquors. Its use is an evil only 
less than the use of whiskey, if less on the whole, and its effect 
is only longer delayed; its incidents not so repulsive, but de- 
structive in the end. In one of our largest cities, containing a 
great population of beer drinkers, I had occasion to note the 
deaths among a large group of persons whose habits, in their 
own eyes and in those of their friends and physicians, were 
temperate, but they were habitual users of beer. When the 
observation began they were, upon the average, something 
under middle age, and they were, of course, selected lives. 
For two or three years there was nothing very remarkable to 
be noted among this group. Presently death began to strike 
it; and, until it had dwindled to a fraction of its original pro- 
portions, the mortality in it was astounding in extent, and still 
more remarkable in the manifest identity of cause and mode. 
There was no mistaking it; the history was almost invari- 
able,— robust, apparent health, full muscles, a fair outside, 
increasing weight, florid faces; then a touch of cold, or a sniff 
of malaria, and instantly some acute disease, with almost in- ADDITIONAL TESTIMONY. 
335 
variably typhoid symptoms, was in violent action, and ten days 
or less ended it. It was as if the system had been kept fair 
outside, while within it was eaten to a shell; and at the first 
touch of disease there was utter collapse, — every fiber was 
poisoned and weak. And this, in its main features, varying, 
of course, in degree, has been my observation of beer drinking 
everywhere. It is peculiarly deceptive at first; it is thoroughly 
destructive at the last.” 
Henry Ward Beecher said : — 
“ Every year I live increases my conviction that the use of 
intoxicating drinks is a greater destroying force to life and vir- 
tue than all other physical evils combined.” 
Alcohol causes Pauperism. We little realize the great 
amount of pauperism that exists in our own country. 
Even to a less degree do we realize that this great 
burden of society is so largely caused by strong drink. 
We have some positive testimony on this point. The 
chairman of the Board of Health of the State of Massa- 
chusetts sent out the following two inquiries to the town 
and city authorities of the State : —• 
“1. What proportion of the inmates of your almshouses 
are there in consequence of the deleterious use of intoxicat- 
ing liquors ? 
“ 2. What proportion of the children are there in conse- 
quence of the drunkenness of parents ? 
He received two hundred and eighty-two replies. 
Among these is the following from the superintendent 
of Deer Island almshouse and hospital: “ I would an 
swer the above by saying, To the best of my knowledge, 
ninety per cent, — to both questions.” 336 
THE ESSENTIALS OF HEALTH. 
The authorities of the city of Springfield reported: 
“We have fed 8,052 tramps. Seldom found one not 
reduced to that condition by intemperance.” 
In the county of Suffolk, mainly the city of Boston, 
eighty per cent of the pauperism was caused by intem- 
perance. Yet we must remember that the excellency 
of the government, and the superiority of the schools of 
Massachusetts, should make pauperism more rare than 
in less favored States. But even here the conclusion is 
forced upon us that a very large per cent of all eases of 
pauperism is attributable to the vice of intemperance. 
Alcohol causes Crime. The United States Commissioner 
of Education says that “ from eighty to ninety per cent 
of our criminals connect their course of crime with in- 
temperance.” 
The Board of Public Charities of Pennsylvania said: 
“ The most prolific source of disease, poverty, and crime 
is intemperance.” 
The Citizens’ Association of Pennsylvania states that 
“ it will not be doubted that two thirds of the pauperism 
and crime are justly attributed to intemperance.” 
The inspectors of Massachusetts State Prison testified 
that in 1868 “ about four fifths of the number committed 
the crimes for which they were sentenced, either directly 
;>r indirectly, by the use of intoxicating drinks.” 
Judge Noali Davis, Ex-Chief Justice of New York, 
says that “ ninety per cent of the criminal business of 
the courts is caused by the liquor traffic.” 
The Hon. A. G. Fairbanks, of Manchester, N. H., tes- 
tifies that he is familiar with over one thousand cases 
of persons confined in jail for various offences, and he 
gives it as his opinion that, “directly and indirectly, it ADDITIONAL TESTIMONY. 
337 
is safe to say that seventy-five per cent of all crimes can 
be traced to the use of alcohol as a beverage.” 
The Hon. William J. Mullen, of Pennsylvania, says: 
“ Of the half million persons who had been committed 
to the county prison of Philadelphia during the last twenty 
years, there had been about five hundred for murder; seven 
hundred for attempts to murder; over forty thousand for as- 
sault and battery, and over two hundred thousand for drunken 
ness. In nearly every case of murder or attempt to murder 
the parties were intoxicated.” 
An evidence of the bad effects of alcoholic liquors 
may be seen in the fact that there have been thirty-four 
murders within the city of Philadelphia during one year, 
each one of which was traceable to intemperance, and 
one hundred and twenty-one assaults for murder pro- 
ceeding from the same cause. Of over thirty-eight thou- 
sand arrests in Philadelphia within one year, seventy-five 
per cent were caused by intemperance. Of 18,305 per- 
sons committed to prison within the year, more than 
two thirds were the consequence of intemperance. 
Judge Allison says : — 
“ In our criminal courts we can trace four fifths of the crimes 
that are committed to the influence of rum. There is not one 
case in twenty where a man is tried for his life in which rum 
is not the direct or indirect cause of the murder.” 
Alcohol causes Wrong Expenditure of Money. In speak- 
ing of the large amount of money expended by the people 
of England year by year for intoxicating drinks, Cardinal 
Manning said: — 
“ Can there he a more complete waste ? Expend it in the 
drainage of England and the culture of the land, and there 338 
THE ESSENTIALS OF HEALTH. 
would be bread for the hungry mouths of the people 5 in the 
manufacture of cloth, and there would be no man and no child 
without a coat on his back; in the building of houses fit for 
human habitation, and there would not be a working man and 
his family without a roof over his head. Nay, I will go fur- 
ther. It is not only a waste, it has a harvest. It is a great 
sowing broadcast; and what springs from the furrows ? Deaths, 
mortality in every form, disease of every kind, crime of every 
die, madness of every intensity, misery beyond the imagination 
to conceive.” 
Alcohol neutralizes Educational Agencies. The New York 
“ Tribune,” in an editorial, thus speaks of the liquor 
traffic: — 
“ It is impossible to examine any subject connected with the 
progress, the civilization, the physical well-being, the religious 
condition of the masses, without encountering this monstrous 
evil. It lies at the center of all political and social mischief; 
it paralyzes energies in every direction; it neutralizes educa- 
tional agencies ; it silences the voice of religion ; it baffles penal 
reform; it obstructs political reform. . . . There is needed 
something of that sacred fire which kindled into inextinguish- 
able heat the zeal of the abolitionists, and which compelled the 
abandonment of human slavery, to rouse the national indigna- 
tion and abhorrence against this very much greater evil.” 
Alcohol is opposed to Good Order. In giving a history 
of the army of the Potomac, the writer says : — 
“I had occasion to observe a remarkable difference in the 
appearance of the different regiments. In some cases I have 
found their men dirty, their camp disorderly, and their whole 
appearance shabby; in others, everything neat and tidy, or- 
derly, and well-disposed. On inquiry, I have found that the 
difference was owing in great degree to “the course the com- ADDITIONAL TESTIMONY. 
339 
manding officers have pursued in relation to the use of intoxi- 
cating drinks. Where, as in a great many instances, the colonel 
has enacted a ‘ prohibitory law,’ and forbidden the admission 
of liquor into the camp, I find everything in the best condition, 
the best health, the best order. I was much gratified to find 
that a great many officers and soldiers abstained entirely, —> 
not because they were compelled, but because they chose to do 
so. No small number of officers in high command are teetota- 
lers. The result of my observations in regard to temperance 
in this great army at Washington is, that the common-sense of 
both officers and men is strongly in favor of prohibition; and 
wherever it has been enforced with fidelity and vigilance, it has 
been in the highest degree beneficial.” 
The Conclusion of the Whole Matter. For many years it 
was the privilege of the author to be associated with the 
eminent Dr. Alonzo B. Palmer, who for so many years 
was dean of the medical department of the University of 
Michigan. Dr. Palmer was like Dr. Davis, in that he 
was a man of wide observation and scholarly attain- 
ments. Shortly before his death he wrote as follows: 
“If chloroform is a narcotic, alcohol is a narcotic; if chlo- 
roform is an anaesthetic, alcohol is an anaesthetic; if one is 
essentially a depressing agent, so is the other. Their strong 
resemblance no one can question. The chief difference is, that 
the alcoholic narcosis is longer continued, and its secondary 
effects are more severe. 
“ There is a connection, often marked, in the use of the dif- 
ferent narcotics. The alcohol habit tends to produce the opium 
habit, and the reverse; one may be substituted for the other, 
and the two are often indulged together. The same principle, 
to a greater or less extent, applies to the widespread tobacco 
habit, and to the less prevalent chloroform, chloral, and hash- 
eesh habits. The indulgence in any one begets a tendency to 340 
THE ESSENTIALS OF HEALTH. 
indulge in others. The habitual use of any of them produces 
a constitutional narcotic state, different from the normal. 
“We thought, and we may sometimes still think, it makes us 
witty. We know from observation it makes men silly. 
“ We thought it brightened the intellect and might make 
men wiser. We find that in the long run, at least, it dulls the 
intellect and makes men foolish. 
“ Wine has been called the ‘ milk of age,’ and we thought it 
supported advanced life. We know that the aged live longer 
and retain their powers better without its use. 
“As a medicine, or prophylactic measure, we thought it 
protected against epidemic diseases. We now know it invites 
attacks. 
“ We thought it prevented and even cured consumption. We 
know it is the most frequent cause of at least one form of that 
disease,—fibroid phthisis. 
“We thought, moderately used, it was good for many things. 
Those who have given most careful attention to the subject be- 
lieve it is good for very few things. 
“ The demonstrations of modern science have shown the 
truth of the ancient saying of the Wise Man. “ Wine is a 
mocker, strong drink is raging, and whosoever is deceived 
thereby is not wise.” 
Cigarette Smoking often does Infinite Harm. We clip 
the following from one of the leading medical journals 
of the world, — the London “ Lancet.” 
“ Scarcely less injurious, in a subtle and generally un- 
recognized way, than the habit of taking alcoholic drinks 
between meals, is the growing practice of smoking cigarettes 
incessantly. The truth is that, perhaps owing to the way 
the tobacco leaf is shredded, coupled with the fact that it 
is brought into more direct relation with the mouth and 
air-passages than when it is smoked in a pipe or cigar, ADDITIONAL TESTIMONY. 
341 
the effects produced on the nervous system by a free con- 
sumption of cigarettes are more marked and characteristic than 
those recognizable after recourse to other modes of smoking. 
A pulse-tracing, made after the subject has smoked a dozen 
cigarettes, will, as a rule, be Hatter and more indicative of de- 
pression than one taken after the smoking of cigars. It is no 
uncommon practice for young men who smoke cigarettes habi- 
tually to consume from eight to twelve in an hour, and to keep 
this up for four or five hours daily. The total quantity of 
tobacco used may not seem large; but, beyond question, the 
volume of smoke to which the breath-organs of the smoker are 
exposed, and the characteristics of that smoke as regards the 
proportion of nicotine introduced into the system, combine to 
place the organism very fully under the influence of the to- 
bacco. A considerable number of cases have been brought 
under our notice during the last few months in which youths 
and young men who have not yet completed the full term of 
physical development have had their health seriously impaired 
by the practice of almost incessantly smoking cigarettes. It is 
well that the facts should be known, as the impression evidently 
prevails that any number of these little ‘ whiffs ’ must needs be 
perfectly innocuous, whereas they often do infinite harm.” 
Tobacco affects Scholarship. Some careful observations 
have been made in many of our public schools and col- 
leges concerning the effects of tobacco on scholarship. 
The following is taken from a recent number of a col- 
lege publication: — 
“ Statistics as to the effects of tobacco-smoking upon students 
have been collected at Amherst and Yale colleges. The non- 
smokers at Amherst are of greater weight than the smokers; 
they are superior in chest-girth to the smokers, and their lung- 
caDacity is higher. The non-smokers are more athletic than 
the smokers, and more successful in athletic sports. The non- 342 
THE ESSENTIALS OF HEALTH. 
smokers at Amherst, as at Yale, have also an advantage over 
the smokers in mental power and in scholarship. The facts 
recently collected in American colleges concerning the physio- 
logical and physical effects of the tobacco-smoking habit are 
instrnctive to the young men who go to college, and also to 
those who do not.” EMERGENCIES. 
343 
CHAPTER XXXIV. 
EMERGENCIES. 
It often happens that a knowledge of anatomy and 
physiology, applied in times of emergency, may save a 
life. To act promptly and properly is the demand. In 
any case of emergency obtain some knowledge of the 
case before sending for the physician: by so doing he 
will be able to bring with him the necessary appliances 
and remedies. With a knowledge of the following sug- 
gestions, one may aid the physician, and possibly pre- 
vent a fatal termination. 
Bleeding. Bleeding from the nose is the most com- 
mon and the least dangerous of all hemorrhages. It 
is generally sufficient to apply cold water to the fore- 
head, and over the nose, or back of the neck, and re- 
main quiet for a short time in the sitting posture. If 
this does not bring relief, then compress the nostrils 
for a few minutes; if the blood clots in the nose, allow 
the clots to remain for a few hours. Placing the hands 
and feet in water as hot as can be borne, will often im- 
mediately stop a severe nosebleed. If the bleeding still 
continues, a physician should be called, who may find it 
necessary to plug the nostrils with gauze or with cotton. 
Bleeding after the extraction of a tooth is sometimes 
profuse; but, as a rule, it is easily controlled by employ- 344 
THE ESSENTIALS OF HEALTH. 
ing pressure over the wounded gums, or by packing the 
cavity with cotton or gauze. A small pad is placed over 
the bleeding surface and the jaws closed firmly over it. 
The pad should be so thick that when the mouth is closed 
there will be firm pressure over the bleeding point. 
Bleeding from the surface of the body can generally 
be controlled by pressure. This can be applied by the 
fingers, or, if the wound be over a bone, a piece of cloth 
may be folded into a small pad and held tightly to the 
wound by a bandage. If the bleeding be slight, frequent 
applications of cold water will probably be sufficient to 
check the flow. 
Bleeding from an artery is recognized by the blood 
flowing in spurts or jets ; from a vein, by its steady flow. 
Burns and Scalds. Great relief is obtained in cases of 
burns and scalds by covering them with soft cloths 
saturated with a solution of common soda, — a table- 
spoonful of soda to a cup of water. An application of 
cream or a thick covering of dry flour will give relief. 
A liniment of equal parts of sweet oil and lime water is 
also very useful. 
Bruises. Applications of cold water, or powdered ice 
in bags is beneficial. The ordinary extract of witch- 
hazel is largely used in such cases. Moist applications 
should be used only for a short time, immediately after 
the injury; if continued for a long time, they lower the 
vitality of the parts. 
Convulsions. Make no attempt to hold the patient 
quiet, but simply prevent him from injuring himself. 
In nearly all cases perfect quiet is the principal thing. 
If the convulsions occur in children, a warm bath will 
often give immediate relief. EMERGENCIES. 
345 
Dislocations and Fractures. If there be reason to be- 
lieve that a joint has been dislocated, or a bone broken, 
the injured parts should be kept perfectly quiet until a 
physician arrives. It is better to wait a few hours for 
his arrival rather than to handle the parts in order to 
learn what is the matter. 
Fainting. The principal thing to remember is that in 
cases of fainting there is not enough blood in the brain. 
Therefore, those things should be done which will pro- 
mote a flow of blood to the head. Place the patient on 
his back and keep the head low, certainly as low as the 
body; do not raise the patient’s head until he has fully 
recovered. Never give alcohol or brandy in such cases ; 
a cup of hot coffee is far better. Dashing cold water in 
the face, or holding an open bottle of ammonia near the 
nose will perhaps aid. 
Fire. If a person’s clothing be seen on fire grasp the 
nearest rug, shawl, blanket or cloak, and wrap it tightly 
about his body. The flames may be smothered by rolling 
the person on the ground. 
Fish Hook. The best way to remove a fish hook that 
has entered the flesh beyond the barb, is to push the 
point through the skin, cut the hook off below the barb, 
and withdraw the remainder. 
Frost Bite. Rub the frozen parts with snow, or very 
cold water; when they begin to sting and become red 
then cease the rubbing, for reaction has commenced. 
A gradually increasing degree of warmth may now be 
applied. 
Poisons. Whenever it is feared that poisons have been 
swallowed, emetics should be given at once. Give a 
dessert-spoonful of ground mustard mixed in a cup of 346 
THE ESSENTIALS OF HEALTH. 
warm water. If vomiting does not occur in a few min- 
utes, the dose may be repeated. In the place of the 
mustard, a tablespoonful of alum may be substituted. 
After the vomiting, give a glass of milk in which are 
the whites of two eggs well beaten. 
Shock. If a person is insensible from some blow, or 
fall, or from fright, and yet none of the organs or tissues 
of the body are injured, place the patient on his back 
and allow a free circulation of air around him. If his 
head is hot, a cloth moistened with cold water may be 
applied to it. 
Sprains. These are often of a serious nature. Bathe 
the parts in either hot or cold water, — whichever gives 
the greater relief, — until the doctor comes. 
Stings. Often the “ stinger ” of wasps, bees, etc., re- 
mains in the wound. This should be removed by the 
fingers, or by small forceps; then apply spirits of 
ammonia. If no ammonia be at hand, try soda water, 
as recommended for burns. Boys have often found that 
binding on ordinary mud gives relief. 
Sun Stroke. Remove the patient to a cool room or 
shady spot, place him on his back, slightly raise the 
head, and apply cold cloths to the head and face. 
Wounds. In cases of wounds the principal thing to 
do, before the arrival of the surgeon, is to prevent too 
great loss of blood. Remove the clothing, if necessary, 
until the injured part is reached, then by pressure tem- 
porarily check the flow. Pressure directly over the 
parts or over the larger vessels leading to them is of 
the first importance. INDEX. 
Absorbents, 149. 
Absorption, 84. 
review of, 90. 
Adipose tissue, 202. 
Air, abundance of, 142. 
amount inhaled, 140. 
deficiency of, 143. 
expired, 136. 
inspired, 136. 
proper amount, 144. 
pure, 144. 
Air cells, 128 
Albumen, 23. 
Albuminoids, 23. 
Albuminous foods, where digested, 72. 
Alcohol, 40. 
a poison, 43, 52, 284, 331. 
abolishes sensation, 288. 
affinity for nervous tissue, 285 
appetite, 50. 
appetite inherited, 51. 
causes crime, 53, 336. 
insanity, 292. 
poverty, 54, 335. 
ulcers, 80. 
wrong use of money, 337. 
chief danger of, 44. 
deception of, 340. 
destructive, 56. 
effects on blood, 102. 
blood-vessels, 80. 
cells, 16. 
cerebrum, 288, 289. 
education, 338. 
eyes, 304. 
heart, 118. 
kidneys, 154. 
Alcohol, 
effects on life, 53, 334. 
liver, 81. 
lungs, 137. 
mind, 291. 
muscle, 197. 
nervous tissue, 283, 286. 
spinal cord, 287. 
stomach, 79. 
temperature, 230. 
inherited effects, 293. 
insanity from, 52. 
not a food, 55. 
not necessary, 332. 
opposed to good order, 338. 
testimony against, 329. 
Alimentary canal, 59. 
Animal beat, 224. 
Animals, cold, warm blooded, 225. 
Apoplexy, 99. 
Apples, 30. 
Arteries, 112. 
Atlas, 167. 
Axis, 168. 
• 
Bacteria, 41. 
Bath, cold, 216. 
value of, 219. 
warm, 218. 
Bathe, when, how, 216, 218. 
Bathing, importance of, 215. 
salt water, 217. 
Beer, 47. 
food-value, 48. 
home-made, 49. 
Bile, 76. 348 
INDEX. 
Bleeding, from artery, 344. 
nose, 343. 
surface, 344. 
tooth, 343. 
vein, 344. 
Blind spot, 301. 
Blood, 93. 
and alcohol, 102. 
arterial, 96, 98. 
clotting, 98. 
composition, 94. 
fibrin, 99. 
venous, 96, 98. 
Blood corpuscles, 94. 
function, 96. 
haemoglobin, 97. 
oval, 100. 
size, 96. 
Blushing, 271. 
Bone, cancellous tissue, 157. 
cells, 159. 
compact tissue, 157. 
composition, 161. 
description, 156. 
marrow, 158. 
microscopic structure, 158. 
reproduction, 162. 
Bones of the chest, 170. 
foot, 173. 
lower extremities, 172. 
nose, 311. 
pelvis, 172. 
skull, 165. 
spinal column, 165. 
upper extremities, 170. 
Brain, 257. 
Brains, two, 268. 
Brandy, 48. 
Bread, 28. 
where digested, 72. 
Bronchi, 128. 
Bruises, 344. 
Burns, 344. 
Cane sugar, 35. 
Canning fruits, 41. 
Capillaries, 114. 
Carbonic acid, 97, 141. 
Casein, 73. 
Catarrh, 314. 
Cellar, ventilate, 147. 
Cells, 11. 
development, 13. 
function, 15. 
growth, 13. 
life, 12. 
motion, 14. 
structure, 11. 
Cement, of teeth, 64. 
Cereal grains, 27. 
Cerebellum, 262. 
function, 269. 
Cerebro-spinal system, 253. 
Cerebrum, 258. 
convolutions, 260. 
function, 268. 
structure, 261. 
Chest, sounds, 135. 
Chloral, 252. 
Chyle, 89. 
Chyme, 73. 
Cider, 44. 
Cigarette smoking, 340. 
Cigarettes, 233. 
and arsenic, 235. 
Circulation, 103. 
aids to, 117. 
general, 115. 
rapidity, 115. 
through heart, 107. 
Circulatory apparatus, 103. 
Clavicle, 170. 
Clothing, 219. 
materials, 220. 
weight, 221. 
Coagulation, 98. 
Coffee, 83, 252. 
Cold, cure, 222. 
results, 154. 
Complexion, 219. 
Conjunctiva, 296. 
Connective tissue cells, 203. 
Contagion, 149. 
Convulsions, 344. 
Cooking, 37. 
Corn starch, 34. 
Coughing center, 270. INDEX. 
349 
Delirium tremens, 290. 
Dentine, of teeth, 65. 
Deodorizers, 148. 
Digestion, 57. 
effects of opium, 83. 
tea, coffee, 83. 
tobacco, 82. 
how affected, 73. 
object, 57. 
table for, 75. 
Digestive apparatus, 58. 
fluids, 57. 
Diphtheria, isolation, 150. 
Disinfectants. 148. 
Dislocations, 345. 
Distillation, 48. 
Dyspepsia, 74. 
Ear, bones, 318. 
drum, 317. 
external, 316. 
inner, 320. 
middle, 317. 
Ears, care, 321. 
Eggs, 26. 
Enamel, of teeth, 64. 
Epidermis, 203. 
uses, 205. 
Epiglottis, 128. 
Equilibrium, sense, 320. 
Eustachian tube, 320. 
Exercise, 191. 
amount, 193. 
benefits, 195. 
forms, 194. 
when, 196. 
Expression, 197. 
Expiration, 134. 
Eyes, care, 302. 
effects of alcohol, 304. 
tobacco, 305. 
oil glands, 297. 
protection, 296. 
Eyeballs, 299. 
function of parts, 301. 
membranes, 299. 
Eyebrows, 296. 
Eyelashes, 297. 
Eyelids, 296. 
Fainting, 345. 
Fat, 203. 
Fatty foods, where digested, 73. 
Femur, 172. 
Fermentation, 42. 
Fibula, 172. 
Fire, to extinguish, 345. 
Fish hook, to remove, 345. 
Foods, 17. 
amount, 36. 
classification, 18. 
inorganic, 18. 
nitrogenous, 23. 
non-nitrogenous, 23, 31. 
uses, 17. 
varieties, 36. 
Foot, arch of, 173. 
Form, good, 163. 
Fractures, 345. 
Frost bite, 345. 
Fruits, 30. 
Gall bladder, 76. 
Gastric catarrh, 79. 
Gastric juice, 72. 
Glottis, 126. 
Glucose, 35. 
Grains, 27. 
Grape sugar, 35. 
Habit, 275. 
Hair, 211. 
muscle, 213. 
Hair-sac, 213. 
Hairs, different animals, 212. 
Healthy body, 278. 
Hearing, 316. 
value, 322. 
Heart, 103. 
auricles, 104. 
beer-drinker’s, 119. 
cavities, 104. 
contractions, 106. 
course of blood through, 107 
effects of alcohol, 118. 
tobacco, 121. 
fatty, 119. 
position, 103. 
pulsations, 109. 350 
INDEX. 
Heart, 
sounds, 111. 
work and rest, 110. 
Heredity', 277. 
Horseback riding, 194. 
Humerus, 170. 
Insanity, from alcohol, 52, 292. 
Insomnia, 281. 
Inspiration, 133. 
Intestine, absorption from, 87. 
large, 60. 
small, 60. 
structure, 85. 
Intestinal juice, 77. 
Jaundice, 76. 
Joints, 173. 
varieties, 174-177. 
Kidneys, 151. 
diseases, from cold, 154. 
effects of alcohol, 154. 
excretory organs, 153. 
structure, 152. 
Lachrymal, fluid, 298. 
glands, 297. 
Lacteals, 88. 
of intestine, 85. 
Larvngoscope, 127. 
Laiynx, 125. 
Ligaments, 173. 
Lime, 21. 
Liver, 76. 
drunkard’s, 81. 
Liver sugar, 77. 
Lungs, 131. 
effects of alcohol, 137. 
tobacco, 137. 
excretory organs, 137. 
why air enters, 131. 
Lymph, 88. 
corpuscles, 89. 
Lymphatic glands, 88. 
Lymphatics, 88. 
of intestine, 85. 
Maple Sugar, 35. 
Marrow, of bone, 158. 
Mastication, 60. 
Meats, 26. 
Medulla oblongata, 262. 
centers in, 269. 
function, 269. 
Mental labor, 278. 
Micro-organisms, 40. 
Milk, 24. 
sugar of, 35. 
where digested, 72. 
Mind, affected by alcohol, 291. 
and body, 269. 
exercise, 278. 
Molds, 43. 
Mouth breathing, 125. 
Mumps, 66. 
Muscles, 180. 
contraction, 184. 
control, 187. 
harmonious action, 187. 
involuntary, 183. 
uses, 181. 
varieties, 180. 
voluntary, 181. 
work and rest, 186- 
Nails, 214. 
Nasal cavities, 124. 
duct, 298. 
Nerve, a, 257. 
cells, 255. 
current, 267. 
fibers, 256. 
tissue, 255. 
Nervous systems, health for, 277. 
two, 253. 
Nicotine, 16, 82, 121. 
Night air, 147. 
Nose, 311. 
Nosebleed, 343. 
Oat starch, 33. 
Oats, 29. 
(Esophagus, 59. 
Olfactory nerve, 312. INDEX. 
351 
Opium, effects, 250. 
digestion, 83. 
nervous system, 294. 
habit, 250. 
preparations, 251. 
Optic nerve, 300. 
Oxygen, 97. 
supports life, 140. 
Oysters, 27. 
Pain, 327. 
Pancreas, 77. 
Pancreatic juice, 77. 
Parotid glands, 66. 
Patella, 173. 
Patent medicines, 251. 
Pelvis, bones of, 172. 
Pericardium, 103. 
Periosteum, 156. 
Perspiration, 208. 
affected, 210. 
checking, 211. 
controlled, 210. 
object, 211. 
Pharynx, 59, 68. 
Physiognomy, 196. 
Plasma, of blood, 94. 
Pleura, 130. 
Poison, 52, 345. 
Portal vein, 87. 
Potash, 22. 
Potato starch, 34. 
Potatoes, 29. 
Poverty, from alcohol, 54, 335. 
Pressure, sense, 326. 
Pulsations, of heart, 109. 
Pulse, 111. 
Pyloric opening, 70 
Pylorus, 71. 
Radius, 171. 
Reflex action, 272. 
acquired, 274. 
importance, 274. 
nerve current, 273. 
Respiration, 135. 
Respiratory center, 270. 
Rest, 279. 
Ribs, 169. 
Rice, 29. 
Rowing, 194. 
Saliva, 66. 
cells, 66. 
uses, 67. 
Salivary glands, 66. 
Salt, 18. 
Scalds, 344. 
Scapula, 170. 
Scarlet fever, isolation, 149. 
Sebaceous glands, 214. 
Sensation, common, 327. 
Sewer gas, 147. 
Shock, 346. 
Skeleton, object, 164. 
Skin, 202. 
checking action, 211. 
coloring, 205. 
Skull, 165. 
Sleep, 280. 
needed much, 281. 
to promote,. 281. 
Smell, 312. 
affected, 313. 
developed highly, 313, 314 
uses, 314. 
Sneezing center, 270. 
Soda, 22. 
Soups, 38. 
Spinal column, 165. 
cord, 263. 
nerves, 264. 
Sprains, 346. 
Standing, 188. 
Starch, 27, 32. 
Starch grains, 32. 
Stings, of insects, 346. 
Stomach, 59, 70. 
digestion, 72. 
effects of alcohol, 79 
glands, 76. 
movements, 73. 
Strength, and alcohol, 198. 
Sugar, 35. 
Sun stroke, 346. 
Swallowing, 09. 
Sweat glands, 207. 352 
INDEX. 
Sympathetic system, 253. 
Synovial fluid, 173. 
Tactile bodies, 206. 
Taste, 309. 
and tobacco, 310. 
buds, 308. 
sense, 309. 
smell, 309. 
Tea, 83, 252. 
Tears, 298. 
Teeth, 61. 
care for, 65. 
fish, horse, serpent, 61. 
shape, 63. 
structure, 63. 
two sets, 62. 
varieties, 63. 
Temperature, and alcohol, 230. 
bodily, 226. 
lowering, 228. 
raising, 229. 
regulation, 227. 
sense, 325. 
Tendons, 183. 
Thoracic cavity, 169. 
duct, 89. 
Tibia, 172. 
Tobacco, 233. 
effects on appetite, 233. 
digestion, 82. 
eyes, 305. 
heart, 121. 
lungs, 138. 
morals, 239. 
nervous system, 233. 
scholarship, 237. 
taste, 310. 
expensive habit, 235. 
filthy habit, 235. 
opium habit, 234. 
strong drink, 234. 
unlawful, 236. 
Tobacco, 
what it costs, in money, 246. 
the body, 240. 
the mind, 243. 
Tongue, 306. 
Touch, 323. 
corpuscles, 323. 
in lower animals, 325. 
sense, 323. 
Trachea, 128. 
Transfusion, 93. 
Tympanic membrane, 317. 
Ulna, 170. 
Urea, 153. 
Vaso-motor center, 270. 
Vegetables, where digested, 73. 
Veins, 114. 
Venous blood, 96. 
Ventilation, proper, 144. 
improper, 146. 
Ventricles, capacity, 107. 
of heart, 105. 
strength, 109. 
Vertebrae, 166. 
Villi, of intestine, 85. 
Vocal cords, 126. 
Walking, 194. 
Water, 19. 
purity, 21. 
source, 20. 
Weight, sense, 326. 
Wheat flour, 27. 
starch, 32. 
Whiskey, 48. 
Wine, 45. 
Winking, 297. 
Work and rest, 193. 
Wounds, 346. 
YEAST, 42.