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A LECTURE
ON
THE HUMAN  BODY.
BY JOHN A. PAKSONS.
y.'2-**
       -geto p*f
PUBLISHED BY C. SHEPARD & COMPANY,
    No. 152 FULTON STREET.
        1854. 
QT
             Entered according to Act of Congress, in the year 1854,
                         By John A. Parsons,
In the Clerk's Office of the District Court of the United States for the Southern District
                             of New York.
Biixin & Bbothses, Printers Rnd Stereotype™, 2u North William street, X. Y. 
THE
HUMAN   BODY.
   The subject of this  lecture is the  human body.
Against this subject there will doubtless be a prejudice
in the minds of many of my hearers, because it is not
delivered by a physician.   I will not undertake to deny
that there are grounds  for this  prejudice.   If I  had
spent a number of years in studying the  human frame
under  able professors, and  had put  my knowledge in
practice in after years, I would, of course, be more com-
petent to lecture on the subject than I can be now.
   On the other hand, my acquaintance with the living
body, though very limited, is more  than  it would have
been had not a failure of my health induced me to in-
vestigate its cause and seek the remedy.
   This, I hope, will be a sufficient  excuse for stating a
little personal  experience.
   When I was in charge of a few small missionary sta-
tions in the western part of New Jersey, I at first occu-
pied a large room on the second  floor of an  ill-built
house, in an exposed  situation.   The  sashes on the  op-
posite sides of the room were so loose that the wind blew
through them  with little hindrance,  and, in winter time, 
4
 even with a large fire, I could not  always keep com-
 fortable.  If any one conjectures that this exposure was
 the cause of my sickness he will be much mistaken, for I
 never enjoyed better health.
   What then was the cause of my disease 1
   It was occasioned by a change of residence.
   I left my cold room for a warmer room in a better
house.   My new apartment  was much  smaller  and
tighter than my previous one.  It had but one window,
which could neither be pushed up nor pulled down, and
of course it could be ventilated only by the entry.  In
this close apartment, which in the winter was heated by
an air-tight sheet-iron stove, I slept at night and studied
by day.   This almost constant occupation of a small,
ill-ventilated, over-heated room, combined with too little
work for the muscles, and too much work for the brain,
soon undermined my health.
   I could not  study to advantage: I gradually lost
flesh, and strength, and color, and appetite.
   Nor was  this  all.  I soon  obtained a cough.  The
first  and the second  attacks of this cold, as it is popu-
larly termed,  though in my case it did not  arise from
exposure, were  driven  away by appropriate treatment,
but not the third.
   It hung on me for months and would not go away.
In the spring I was so reduced, that a short walk at a
slow pace would tire me, and I shivered under an over-
coat in the mildest weather.
   I was obliged to leave  my station and go home.
Then I consulted a distinguished  physician, who, after
sounding  my chest, told a relation of mine that, I had
the consumption, and would never preach again. 
5
   Although this opinion was kept from  me, I  knew
that my case was well nigh hopeless, for both my mother
and  one of my  brothers  died  of consumption, and
neither of them, when first subjected to medicinal treat-
ment, was so weak  as I was then.  It was this which
induced me  to read  a few popular works  on the human
frame, one of which was written by Dr. Andrew Combe,
formerly royal consulting physician, in England.
   The  last named work was the  more suited to  my
case since the doctor had inherited a consumptive ten-
dency from his parents, and had  preserved his life with
the greatest care.
   The  conclusion to which I came,  from the  slight
knowledge of my system thus acquired, was this: that in
order to regain my health I must exercise my brain less
and my muscles more, that  I must eat simple  food and
drink pure  water or milk, and that I must take a daily
bath, and breathe  pure air as much as possible.   Accord-
ingly I put these things in action.   I ventilated  my sleep-
ing room during the day, and kept the window partly,open
in the night, and  spent most of the day in the  open  air.
   At first I was so weak, that I was obliged at frequent
intervals to  sit down on  the wayside and rest, before I
could resume my  slow and  tottering walk.
   By this  means, however, since the season was favor-
able, I was  enabled to spend almost the whole day in
the open air.
   This course of treatment I pursued for  months, and
gradually regained my health.
   It was a long time before I  got rid of my cough,
even after I had gained an  appetite and was improving
in flesh and color, but at  length it left me. 
6
   The residt was that I, who had panted after walking
a few rods, and had shivered in the mild breath of spring,
could now run up and down the mountains and endure
more cold than most.
   Hoping, my hearers, that you will excuse this personal
narration in consideration of the object, permit me to
remark, that  my knowledge of the human frame  then
began, I have since  extended, although I am aware
that  it is very limited.   You will not, of course, expect
me to  treat of every part of the body in one  lecture,
nor would it be possible.  It is my design to treat only
of some of its most important organs.
   If I shall succeed in giving my hearers a clear con-
ception of these, then my object will  be accomplished.
   I intend to treat of the blood vessels, of the organs
that  purify the blood, and of those which  convert the
food  into blood.
   And first of the blood vessels.   The blood vessels
are the heart, the arteries, the capillaries and the veins.
The  heart is a hollow muscle lying in the chest, partly
to the left, between the two lungs.  The muscles  form
the lean flesh and are the instruments of power,  causing,
by their contractions, every motion of the  body.  The
heart is divided into two cavities, one on the right  and
the other on the left, which have no direct communica-
tion  with each other.  These  cavities  themselves are
divided each  into two chambers, which are called the
right auricle, and the right ventricle, and the left auricle,
and the left ventricle.   The right auricle opens  into the
right ventricle, and the left auricle opens into the left ven-
tricle.   From the right ventricle goes a large tube called
the pulmonary artery, which separates into two branches, 
7
one leading to the right lung and the other to the left.
   These  branches  divide  and  subdivide  into almost
countless tubes, until they are brought into contact with
all the air-cells of both lungs.   Having done this they
unite into  larger tubes called pulmonary veins,  and
these again into  larger, until forming four great veins,
two  from each  lung, they communicate  with the left
auricle.
   This cavity opens into the left ventricle.
   From  this chamber arises  the main artery of the
body, called the aorta.   This divides and subdivides into
smaller and still smaller arteries, which  are  distrib-
uted  throughout  the  body.    From  these extend the
capillary vessels, which are many times thinner than the
finest hairs, and  form a network through the whole
structure of the body, impermeating every organ, every
muscle, every bone.  They even penetrate the nails, and
the whole length of  every hair.  These capillaries com-
municate with the veins which  run in an opposite direc-
tion  to the arteries.  These veins  unite into larger ones,
and  these  into  still larger, until they form two great
veins, one of which  opens into the right  auricle  from
above, and the other into the same cavity from beneath.
Such is the structure of the heart, the arteries, the capil-
laries, and  the  veins.    What now  causes the blood
to circulate  through  these vessels %
   It is caused in part by the alternate contraction and
relaxation of the four cavities  of the heart.   The open-
ings that lead into these  cavities, and out of them, are
guarded by valves that permit the blood to pass through
them on its way from the veins to the arteries, but pre-
vent  its  return.   The  auricles contract when the ven- 
8
tricles relax, and  the ventricles  contract when the au-
ricles relax.   Thus the auricles force the blood into the
ventricles at the very time that the ventricles are empty
and ready to receive it.
    Having thus seen how the ventricles  receive  their
blood, let us now inquire how the auricles become filled
with blood.
    It is  done in this way.   When the auricles relax,
they are, of course, enlarged, and thus are partially empty.
    Into  the vacuum  thus formed in the right auricle
the  blood is  forced  from the veins of the body by the
pressure of the  air.   The same cause also  drives the
blood of the pulmonary veins into the left auricle.   The
right auricle, when filled with blood, contracts and forces
it  into the  right ventricle.   The right ventricle, in its
turn, contracts and drives the blood among the pulmonary
arteries.   The left auricle being filled with blood at the
same time with the  right  auricle, also contracts and
forces it  into the left ventricle.
   The left ventricle in its turn contracts and drives the
blood into the  main  artery and its branches.   The
arteries contract behind the blood and force it into the
capillaries.  Through the capillaries the blood is urged
by nervous influence into the veins.   It is driven along
the veins partly by a little contraction of their coats,
but  mainly by the pressure of the  air which forces it
into the right auricle every time it  relaxes.   In order
to prevent the blood from flowing backward in the veins
when the right  auricle  is  contracting, they are  pro-
vided with valves  that allow the blood to pass onward
but  prevent  its return.  The blood easily circulates
through  the  pulmonary  arteries and veins, since  it is 
9
forced into  the pulmonary arteries by the contraction
of the right ventricle, and it  is driven from the pul-
monary veins  into the left auricle by the pressure of
the air.
   Thus the blood is drawn from every part of the body
to the right side of  the  heart, and sent  thence to  the
lungs, and it is drawn, from the lungs to the left side of
the heart, whence it is distributed to every part of  the
body.
   I have stated that the blood vessels are distributed
among the lungs.  These organs therefore  now present
themselves for our consideration.
   The lungs, two in number, are  placed  in  the  chest,
the one on the right side of the heart, and the other on
the left.  They are  composed  of six hundred millions
of little air-cells.  These are grouped together in sponge-
like masses, and  every mass  is united  to a small tube
which opens into every cell.  These tubes communicate
with a smaller  number of larger  tubes, and these with
others still fewer  and larger in number, until they unite
into two great tubes, one of which comes from the right
lung and the other from the left.   These are the  bron-
chial tubes,  and they unite in the  windpipe, which com-
municates with the  outer air  by  the  nostrils and  the
mouth.   Such is  the structure of  the lungs.
   And now for the  manner of breathing.
   Before explaining  this process we must look at  the
formation of the chest.   The chest is the large cavity
in the upper part of the trunk.  The walls of the chest
are supported by the ribs.   The ribs are the semicircular
fiat bones, twelve on each side of the  body, that curve
around within the chest.   All  except  the four lowest 
10
are fastened to the breast-bone in front, with an elastic
substance called cartilage.
   All are attached to the spine behind by hinge joints,
and thus can be moved upward and downward.
   The ribs  are lower  before  than behind, and curve
downward at the sides.  Now, since the ribs are lower
before  than behind, you will perceive that when they are
raised the breast-bone is thrust outward, and the chest
is enlarged in front.
   For the same reason, when the ribs are lowered, the
breast-bone is forced inward and the chest is diminished
in front.
   Again, since the ribs  curve  downward at the sides
when their middle parts are raised, the  chest  will be
enlarged from side to side, and when they are lowered
the chest will be diminished from side to side.
   The principal muscles that promote breathing are the
diaphram, the abdominal muscles,  and  the muscles be-
tween the ribs.
   The diaphram  fills the bottom of the chest and is
fastened to the lowest ribs.
   The abdominal muscles are placed in the lower  part
of the  trunk beneath  the  diaphram, from which  they
are separated by the liver and other organs, and they are
fastened by tendons to the ribs.  The muscles  between
the ribs  pass crosswise from rib to rib on both sides of
the body. WThen we are about to draw in tho breath the
diaphram contracts downward, and swelling in the middle
presses the ribs out, and the muscles between  the  ribs
contracting from above, raise  the middle of every rib.
   The chest is thus enlarged beneath, in front, and on
both sides, and  the air in  the  lungs, which are never 
11
entirely empty, expanding with the chest, becomes rari-
fied, and  cannot resist the pressure  of  the outer air
which rushes in and fills the lungs.  Thus we breathe in.
   What now takes place when we are about to breathe
out'?   The abdominal muscles  contracting pull  the
ribs downward and inward, and enlarging in the middle
press  the liver and other organs against the diaphram,
and force it up into the chest, and  the muscles between
the ribs contracting from beneath pull down the middle
of every rib.  The chest is thus diminished beneath, in
front, and on both sides, and compresses the lungs and
forces the air  out.  Thus breathing is like blowing a
bellows.
   The alternate  enlargement and  diminution of the
chest  in breathing, must modify to some extent the cir-
culation of the blood.  When the chest is enlarged, the
chambers  of the heart are also enlarged, and hence will
receive and discharge more blood." When  the  chest is
diminished the chambers of the heart are also diminished,
and hence will receive and  discharge  less blood.   Thus,
at the very time that the lungs are filled with air, more
blood is sent among them,  and less blood when  they are
partially empty.  I have before stated that it is  the con-
traction of the left ventricle which  drives the blood into
the arteries.
   This begets an impulse  that is felt to the extremities
of the body, and is called a pulsation, and by repetition
forms the  pulse.
   There  are  two pulsations every time we breathe in,
and two every time we breathe out.
   Thus there are four pulsations  for every respiration.
Hence, if we wish to ascertain the state of an invalid's 
12
 pulse without  disturbing him, we have only to count
 the  number of times he breathes and  multiply it by
 four.
   In the vigor of life we breathe, on an average, eigh-
 teen times a minute, and have seventy-two pulsations.
   In infancy it is more, but in old age it is less.
   We thus perceive  that there is a regular proportion
 between the quantities of air and of blood  that are  sent
 to the lungs.  It is computed that, on an average, a pint
 of air enters the lungs at every inspiration, and that  one-
 eighth of  a pint of blood is distributed  among them at
 every pulsation.  Since, then, there are four pulsations
 for every respiration,  four-eighths  or one-half of a  pint
 of blood is sent to  the lungs  for  every pint of air.
 This in  twenty-four hours amounts to 25.920 pints of
 air, and 12,960 pints of blood, which is equivalent to
sixty hogsheads of air and thirty hogsheads of blood.
   It may be  asked how so great a quantity of blood
 can be sent to the lungs when there are only about  one
hundred pints in the body.
   It is done by continual circulation, the  same blood,
though in a changing  state, returning often to the lungs.
The  blood makes the  entire circuit of the body in  six
minutes, and this is repeated two hundred arid forty
times in twenty-four hours.
   We have seen, my hearers, that a pint of air enters
the lungs at every inspiration, and that one-eighth of a
pint  of blood is sent among them at every pulsation.
   You will naturally inquire, how is it that such quan-
tities of blood and of air can exert much influence over
 each other during the short time they are together ;  for
 we no sooner breathe in the air  than we breathe it out 
13
again, and the blood travels four times as quick as the
air.  It is done in this way.
   The  air on entering the lungs is distributed among
six hundred millions of air-cells, and the blood is still
more minutely divided, for the capillaries in which it is
contained form a network over every one of these cells.
   Thus the air and the blood, being subdivided among
each other in quantities too small for human conception,
work great changes in each other during little time.
   These statements may give some idea of the import-
ance attached by the Creator to  the purification of the
blood.   But this conception will be increased if we con-
sider the extent of surface over which the air and the
blood are spread, when exposed to each other's  influence
during twenty-four hours.   Every pint of air we breathe
in is diffused over the whole surface of the lungs, which
amounts to one hundred and  fifty square feet.
   It is easy to compute the space over which 25,920
pints are spread.
   This amounts to 3,888,000 square feet, which exceeds
the eighth of a  square mile by 403,200 square  feet.
But we  have  seen  that the  blood is sent to the lungs
four times as often as the air,  and hence is spread over a
surface four times as great.
   This amounts to 15,552,000 square feet, which is the
space occupied by 6,620 city  lots, and exceeds the  half
of a square mile by  1,612,800 square feet.
   So great are the surfaces over which such large quan-
tities of air and of blood  are brought  into such  inti-
mate contact every day.
   Now no one will suppose  that the air and the blood
are thus brought together for no purpose, and that on 
14
leaving the lungs they are in the state as before.  To
this  point I will now direct your attention.  The cells
of the lungs, and  the coats of the pulmonary arteries,
are composed of delicate transparent membranes, that
permit  the  gases  to pass through them but not the
blood, and hence the latter can be changed by the action
of the air without entering the cells of the lungs.
   What is the nature of this change 1
   Oxygen passes from the air into the blood, and car-
bonic-acid gas passes from the blood into the air.  What
is oxygen, and what is carbonic-acid gas 1   Oxygen is a
gas that has a great attraction for the elements of almost
all substances, and hence readily combines with them.
It forms, by weight, one-fifth of the air, eight-ninths of
the ocean, nearly one half of the globe, and much more
than half of the bodies of all plants and animals.
   Without it  we could not  produce either light  or
heat.   When wood, for example, is burning, the oxygen
of the air combines with the charcoal of the wood, which
is called carbon, giving out light and heat, and forming
carbonic-acid gas.
   Thus we see that  carbonic-acid gas  is a union of
oxygen and charcoal.  It has properties differing alto-
gether from those both of the solid and gas which join
to form it.
   It is a poison, as is proved by the death of those who
have remained a short time in a close room where  char-
coal was burning.   It is  from  the  accumulation of this
gas in the blood, more even than the want of  oxygen,
which causes death in drowning.
   Thus we see that the blood parts with a poisonous
gas to the air, and takes  from  it a healthful element in 
15
return, and thus from two causes the air is made impure
while purifying the blood.   But there are other  impu-
rities to be removed.  These  are  dissolved in water,
which,  in the  form  of vapor, passes from  the  blood
along  the  whole  length  of the  tubes that branch
among  the  lungs, and thus pass  into  the  outer air.
Thus, also, the air is made impure while purifying the
blood.
   In  addition to  the  other benefits which the blood
receives from the air, it obtains from it electricity.  This
is stored up by the nerves, which  furnish it to the
muscles and enable them  to perform the functions of
the body.
   We have seen that the  air of the lungs changes the
nature  of the blood.  This change  of nature is accom-
panied  by a change of color.  Before reaching the lungs
the blood is of a dark-red  color, but after passing from
the lungs it is of a bright  scarlet.   It retains this color
until it enters the capillaries,  where  it undergoes a
change from bright scarlet  to dark red, and in this con-
dition enters the veins.
   What causes this change from bright scarlet to dark
red blood 1   The causes are twofold.
   The oxygen of  the blood unites with the tissues of
the  body, for which it  has great attraction,  and forms
various compounds, but chiefly carbonic-acid gas.
   Thus portions  of  the body are  destroyed, but they
are immediately replaced by new flesh formed from the
blood.
   The blood being thus deprived  of its healthful ele-
ments, and filled with noxious ingredients, becomes again
of a dark red color.   We have seen that our own flesh is 
16
constantly wasting away, and as constantly being re-
newed.
   This  pulling down and  rebuilding of  the  body is
constantly going on in every  tissue, even in the solid
bones, so that on an average we obtain an entirely new
body every five years.
   It proceeds faster in the  young than in  the old, and
in the healthy than  in  the  diseased.   In youth  the
supply is greater than the waste, and hence at this period
we grow larger.   In manhood the supply and waste are
equal, and hence our bodies then remain the same in size.
   In old age the waste is greater than the supply, and
hence at this period we  gradually waste  away until
feeble nature  cannot repair  the crumbling body, which
returns to the  elements from which it was formed.
   I have stated that the wasting away of  the body in
the capillaries takes away oxygen from  the blood and
fills it with carbonic-acid gas.  The  removal of this car-
bonic acid,  and the restoration of oxygen is  accom-
plished mainly by the lungs.
   In performing this work,  however, it is aided by the
skin, which, over its whole surface, permits carbonic-acid
gas to go out from the blood to the  air, and oxygen to
come in from the air to the blood.
   Thus the  skin breathes  as well as the lungs, and
poisons the air, and robs it of nutriment while purifying
the blood.
   But the skin serves a more  important  purpose even
than that of breathing.
   All over the surface of the  body are little openings
called pores.  There  are  seven millions of tubes that
pierce through the  skin,  and communicate  each with  a 
11
little bag  called a sweat gland.   These glands are  all
surrounded with blood vessels.
   What  duty do these glands perform 1
   Before answering this  question I must make a little
explanation.
   When the tissues of the body are disorganized  by
their union with oxygen, not only does carbonic-acid gas
result, but certain other compounds of  which nitrogen
forms a part.
   What  is nitrogen \
   It is a gas that has only a feeble attraction for a few
elements,  and hence makes but few combinations, and
from  these it is  easily separated.   It is for  this reason
that nitrogen plays an important part in  those sub-
stances that are easily decomposed.  It forms, by weight,
nearly four-fifths of the air, and one-sixth of the muscles
of the body,  and is a constituent of the  most important
articles of food.
   The compounds of nitrogen with other elements are
dissolved  in  water.  The water  for  this  purpose  is
obtained partly  from the  liquids we drjnk, and  partly
from  the  union of oxygen  and hydrogen which  result
from  the  decomposition of the tissues.  Hydrogen is
the lightest of gases, having about one-fourteenth the
weight of common air.   It forms one-ninth of the weight
of water, and is  an essential part of vegetables and ani-
mals.   When oxygen and  hydrogen combine  to form
water they give  out great heat.  Thus the temperature
of the body  is preserved as well as by the union  of
carbon and oxygen.          >
   The water thus obtained dissolves the compounds of
nitrogen, and oozes from the blood vessels into the sweat
       2 
18
glands, where, being  converted into vapor by the heat
of the body, it issues from the pores, and is called the
insensible perspiration.   Since the pores of the skin are
seven  millions  in number, and are, on an  average, a
quarter of an inch long, their united length is 1,750,000
of inches.   Now, since  63,360  inches make a mile, we
find by division that the united length of the pores of
the skin is  nearly twenty-eight  miles.   I have  stated
that  the conversion of  the impure water of the blood
into the vapor that issues from the pores of the skin, is.
due  to the  heat  of the body.   It hence follows, that
when we perspire freely, much heat passes from us, and
less heat when we perspire less.  The  sweat  glands are
thus the regulators of animal heat, and act much more
freely in summer  than in winter.   On the contrary, the
lungs act more freely in winter than in summer, for cold
air, being more  dense than warm air, will  give more
oxygen to the blood, and receive more carbonic-acid gas
in return.   Thus  each is more active when the other is
least so, and thus  it was ordained, that in all seasons the
blood might be purified and the health preserved.
   The pores of  the  skin are  liable to be closed by a
thin glazing formed over their mouths.   This glazing is
caused  by the hardening of some  impurities that pass
•through them, and also  by the old  oil that is secreted
from  the blood for the purpose of rendering the skin
flexible.
   The removal  of this glazing is one of the benefits
which are derived from a daily bath.  Those  persons
therefore, who wash the entire body, pass off impurities
much  more freely from  the skin than  those who wash
•only the face and the hands.  The insensible perspira- 
19
tion  passes, of course, into the air, and thus while  the
blood is rendered pure the air is made impure.
   The amount of morbid matter  that passes off from
the healthy skin in twenty-four hours, is  estimated at •
two pounds.
   The amount of impure and poisonous matters  that
pass  out of the blood through the skin and the lungs,
is almost twice as much as are removed by the liver, the
kidneys, and the large intestine combined.
   Think of this  fact, think of  the vast  volume of
gaseous matters that are required to weigh  two  pounds,
think of the sixty hogsheads of poisonous air and  foul
vapor that is discharged from the lungs, and then you
may  realize  how much purer is the  air of  the  heavens
than the air  of a house, and then you may feel the need
of ventilation.
   It is supposed by many that  the draught  up  the
chimney, making a vacuum in the room,  and thus caus-
ing the pure air to rush in through the crevices of the
door and windows, will furnish a sufficient ventilation.
This might be the case in an ordinary apartment, were
it  not for the  fact that the outer air being colder, and
of course heavier  than the air of the room, will fall to
the floor as soon  as it  enters the room, and be drawn
into  the stove, and thus the fire  will be fed with pure
air, while we breathe the poisonous exhalations of  our
own  lungs and skin.
   How can this be remedied \  In a very simple way.
Let a hole about the width of a stove-pipe be made into
the  chimney from the upper part of the room.  Then
the upward draught of the chimney will  draw away the
foul  air from the upper part of the room, and the pure 
20
 air from  the windows and door will rise to supply its
 place.
   To this it will be objected, that a hole in  the upper
 part of the  chimney does  not  look very  ornamental.
   This objection will be  removed simply by driving
 two spikes in the wall beneath the hole and one above
 it, and by resting a picture, or engraving, on  the lower
 spikes, and letting  it hang over in front from a  cord
 which is fastened to the upper spike.  Thus the air can
 find ready entrance into the chimney behind the picture,
 while the appearance of the room, as well as the health
 of its inmates, will be  improved.   Of  course,  my
 hearers, much remains to be said respecting ventilation,
 but its further discussion would lead me away from my
 subject.  Let us now proceed with the purification of
the blood.
   Among the organs which serve this purpose are the
kidneys.   The kidneys are  two in number, and are  situ-
ated in the large cavity beneath the chest, in  the lower
part of the trunk.
   This large cavity is called the abdomen.
   The kidneys are placed half way from the  top to the
bottom of the abdomen, one on each side of  the spine.
 They are small bodies, and weigh each about four ounces.
   The length  of each kidney is  twice  its width, and
its width is more than twice its thickness.   Its shape is
 somewhat of a flattened oval.   Its structure is dense, but
it is easily torn apart.
   Each kidney has an outer layer, and several internal
bodies arising from  that layer.
   The outer layer is composed of small tubes  and blood
vessels, and a large number  of little globules.   Into 
21
every one of these globules a tube enters, and is coiled
about many times, and is interwoven with a network of
blood vessels, and  then  passes out again.   Such is the
structure of the outer layer.
   From the internal surface of this outer layer a number
of pale red bodies, shaped like pyramids, project towards
the centre of each kidney.   The bases of these pyra-
mids, resting upon the outer layer, touch each other, but
their  sides are  apart, and hence, in the centre of  each
kidney, and between the adjoining pyramids, there is a
hollow space.   This hollow space communicates with a
tube on the outside of the kidney which leads downward.
   Let  us now examine the  structure  of the pyramids.
Each pyramid  is  composed  of a number of straight
tubes which run from its base to its point, and are  con-
tinuations of  the tubes of the outer layer.   The spaces
between these tubes are filled with a spongy pith.   Such
is the internal structure of these pyramids.   Let us now
look to their covering.   The tubes of the outer layer
pass not only to the inside of the pyramids but also  to
their  outside.  In doing so  they are  interwoven  with
blood vessels, and form a delicate  covering to  each
pyramid from its base almost  to its point.
   Such is the structure of the kidneys.
   And how do they act in purifying  the  blood ?  In
this way.   The dark red blood circulates through the
blood vessels of  which  we have spoken,  and certain
impurities dissolved in water, ooze into the little tubes,
and then pass into the hollow space of each kidney, and
thence are conducted  out of the system.   What is the
nature of the impurities thus removed %   It is  a  sub-
stance composed  mainly of carbon, oxygen, hydrogen, 
22
 nitrogen, and sulphur, for sulphur, as well as phosphorus,
 and other elements, form a part of the body and the blood.
    It is by the kidneys that the salt and other mineral
 impurities of  the blood are removed.   The next  pu-
 rifier of the blood is the liver.  The liver is the largest
 organ of the body,  and  has an average weight of four
 pounds.  It is placed in the upper part of the abdomen,
 immediately beneath the diaphragm.  It lies mainly on
 the right side of the body, though it extends to the  left
 side beyond the centre of the body.  Above, it bulges
 out, but it is scooped out beneath, and its edges  are very
 thin.   On the  right side  its middle part is very thick,
 but thence to the extreme left it diminishes in thickness
 like a wedge.
   The liver is a gland.   In its lower part  there is  the
 gall bladder, which is a pouch leading into the small
intestine.
   From the gall tube proceeds the main tube of  the
liver.   It has branching tubes, and branches of branches,
 each ending in a cluster of little pouches.
   The outside of every one of these pouches and tubes,
and the outside of the gall bladder, is brought into con-
tact with branching veins that bring back the dark  red
blood from the  stomach, small intestine, and pancreas.
   From the impure blood on the outside of the tubes,
 and pouches of the liver, bile is secreted  and poured
into the small intestine.  From the impure blood on  the
 outside of the gall bladder, gall is formed, and  is  also
poured into the  small intestine.   And  now what  be-
 comes of the gall and the bile \  They pass along  the
 folds of the small intestine, which  is a tube very long
 and very narrow, until they reach the lower part of  the 
23
right side of the abdomen, where they pass through a
valve into  the  large  intestine.  The large  intestine is
wider than  the small intestine, but  not  so  long, being
about five  feet in length.   It rises for some distance
in the abdomen, and curves around to the left, forming
almost a complete circle before it leads out of the body.
   It is composed of three coats, the outer being a thin
shining membrane, which is pierced by numerous small
tubes, each  communicating with a  little bag.  These
secrete from the blood a thin,  watery fluid, for the pur-
pose of making slippery the surface of the large intestine
and  protecting it from injury.   The inner  coat is also
a delicate membrane, pierced with many small tubes,
each opening into a little bag.  These secrete from  the
blood a slimy fluid called  mucus, which gives a smooth
surface.  Between these two membranes there is a coat
of muscular fibres.  Part  of these run lengthwise and
part run around the large intestine.
   The circular fibres are much more numerous at fre-
quent points along this organ,  and hence give it the ap-
pearance of a  series  of pouches.  The long fibres, by
contracting, make the large intestine shorter, and  the
circular  fibres, by contracting, make it  narrower, and
thus it is capable of a variety of motions.   And now for
the use of this organ.  Its inner coat is pierced not only
by the mucous tubes, of which we have spoken, but also
by about ten millions of  other little  tubes communica-
ting with small bags.   These secrete from the blood its
more solid impurities.  As these impurities are poured
into  the  large intestine, they are mingled with the gall
and the bile received from  the small intestine.   When
these materials have  sufficiently accumulated, the mus- 
24
cular fibres contract behind them and thus drive them
out of the system.
   Such are the organs that purify the blood.
   The blood of the veins, being thus freed from most
of its noxious ingredients, does not receive any further
purification until it reaches the lungs.
   But  there is a  portion of the impure  blood of the
capillaries which is separated from  the rest, and is con-
veyed to the right side of the heart in different vessels
from the veins.
   The fluid thus separated from the blood looks some-
thing like water.   It is  called lymph, from  lympha, a
Latin term for water, and the  vessels  which convey  it
are called lymphatics.  The lymphatic vessels begin in
a network of  delicate  tubes which connect them with
the capillaries.   Hence they proceed in parallel tubes
from almost every tissue  of the body to the root of the
neck, when they empty their  contents  into  the veins.
The lymphatics are provided with valves that allow the
lymph to pass through them on its way from the capil-
laries to the heart,  but  prevent its return.  In their
course they are intercepted by many small egg-shaped
bodies called glands.
   Before  entering these glands the lymphatic vessels
divide into several  smaller tubes, which enter the glands
and form a network within them, and  bend hither  and
thither  so as  to  present much surface in little space.
After going out of the glands these little tubes unite,
and form  larger  tubes the same in number as before.
These glands are fully supplied with nerves  and blood
vessels.   The  arteries and  the organic  nerves enter
them, and branch, and bend hither and thither, and are 
25
interwoven in  every  direction with  the lymphatics.
Thus in small quantities, over large surfaces, though in
little space, the transparent lymph, and the thread-like
nerves, and the scarlet blood, are brought into intimate
contact, and exert great influence over each other in a
short time.
   What is the nature of this influence \
   This is a subject surrounded with darkness.  There
is no doubt that the blood becomes noxious from contact
with the lymphatics, and requires to be purified before
it can enter the arteries.   But what change does it exert
upon the lymph %
   We know that when a  poisonous substance enters a
lymphatic gland, the blood rapidly accumulates within
it, forming an inflammation.   This it does in order that
either by nervous influence, or by parting with some of
its own elements, or by removing some of the  elements
of the noxious compound, it may cause it to  pass into
new combinations and become harmless.  Thus poison
in the lymphatics is far less injurious than poison in the
veins.
   But I apprehend that  the  chief change which the
blood makes in  the lymph consists  in a different ar-
rangement of its ultimate  elements.   What do I mean
by this \
   I can best  explain it  by an  illustration.   Certain
plants have the power of forming sugar in their tissues.
Of what is  sugar formed %  It is composed of carbon,
and oxygen, and hydrogen. Now oxygen and  hydrogen
both exist in  sugar in the exact proportions in which
they combine to form water.   Thus sugar is formed by
the  union of charcoal  and of the elements  of water. 
26
But can the chemist produce sugar out of charcoal and
water 1
   No, it is not in his power, for sugar is  the product
of life.  With the exception of the vital power residing
in the bodies of animals, it is the only living plant drink-
ing water from the ground, and from the air, and breath-
ing in carbonic-acid  gas, and breathing out oxygen,
while retaining  the carbon, that  is  able  to  combine
carbon and the elements of water in such a way as  to
form  sugar.  But more than  this.   A  grain of wheat
contains a  large  proportion of  starch  but very little
sugar.   Let it, however, be planted in the earth, under
the influence of air, and water, and light, and heat, and
electricity, and it  will germinate  and  convert its starch
into  sugar.  Again, in the ripening  of the grain the
plant converts its  sugar back to starch.
   This it  does not by the  addition or subtraction of
one or more elements, but by arranging  them in a dif-
ferent way; for the chemist, on analyzing  starch, finds
it  to consist of the same element as  sugar, and  in the
same proportion.   Now no one would  suppose that sub-
stances possessing such different properties as sugar and
starch, differed from each  other  only in a  different
arrangement of  their ultimate elements, were he not
told so by the  chemist.  Let us not then be surprised,
when we are informed that the change which the blood
makes in the lymph consists not  so much in  the addi-
tion  or  subtraction of elements  as  in their  different
arrangement.  The lymph being thus changed and par-
tially purified, is poured into the veins at the root of the
neck, where it is mingled with  the blood, which has also
been partially purified by the organs we have mentioned. 
21
   Then the red blood and the clear lymph are sent to
the lungs, whence, afcer parting with  carbon and impure
vapor, and receiving oxygen and electricity, they become
scarlet, and are sent to every tissue of the body pregnant
with the elements of destruction and restoration.
   We have seen that  the oxygen of the air enters the
blood, combines with the tissues of the body, and forms
noxious compounds which are removed from  the system.
   We  have  also  seen that the  wasted  tissues  are
replaced by new flesh formed from the blood.   Unless,
then, ne^w blood is  made to counterbalance  the loss of
the old, we will gradually waste away and die  of starva-
tion.  To prevent  this result we have  the organs of
nutrition.
   These are the teeth, the salivary glands, the stomach,
the small intestine,  the pancreas, and the chylous veins.
   When the  food enters the  mouth,  it  is cut,  and
ground, and mashed by the teeth.   Hence, if a person
has no teeth, his food should be divided very minutely
before it ^enters the mouth.  The motion of  the jaws in
chewing,  and  the rolling of the food about  the mouth
by the tongue, excites the salivary glands to action.
   What is a salivary gland \  It is a tube, with branch-
ing  tubes, and branches of branches, each ending in a
little pouch.  Between these pouches and tubes, there
is soft cellular  flesh,  which is inclosed  in a delicate
membrane, making the whole the  shape and size of a
robin's egg.
   The cellular flesh is impermeated in every direction
with nerves and arteries, and thus the  blood is brought
into contact with the outside of every pouch and tube,
and  is thus  spread over great surface in little space. 
28
    These glands are six in number, and are imbedded
 in the flesh, two before the ear, two under the jaw, and
 two under the tongue, and every one has a continuation
 of its main tube, that opens in the inside of the mouth.
    The desire for food, and its presence in the mouth,
 causes a flow of nervous influence and blood to these
 glands.
   From this blood saliva is made, and exudes into the
 pouches and  tubes  of the  glands, and  issues into the
 mouth.  There it is mixed  with the food, which is thus
 prepared for the action of the stomach.
   In order to promote the flow of saliva, it is better  to
 have our food in the solid than in the liquid form ; and
 for  the same reason those who have no teeth should roll
 it about the mouth before swallowing it.  Since the act
 of sucking promotes the secretion of saliva and mixes
it with the  milk, it is not proper to feed  an infant with
 the spoon.  From the fact that saliva is made from the
blood, if the blood be pure  the saliva also will be pure.
 Impure saliva, therefore, is  a sign  of unhealthy  blood.
 The same statement may be made respecting the mucus.
   The mucus is the  slimy substance spread  over the
 surface  of  the mouth and  tongue in order to make a
 smooth passage for the food.  It issues from little tubes
that pierce the  lining of the mouth and tongue, and
 communicate  each with a  little bag surrounded with
blood vessels.
   Since the mucus, like the saliva, is formed from the
 blood,  its  purity  or impurity will also indicate  a cor-
 responding state of the blood.  Hence the  physician  is
 often able to judge of  the condition of the patient from
 the color of his tongue. 
29
   But to return to the process of nutrition.
   The food having been chewed and mixed with saliva,
is thrust by the tongue into the back-mouth.  The back-
mouth is a pouch of a funnel shape, and leads  down to
the windpipe and the gullet.   The windpipe is in front
of the gullet, and has a valve over its top  which closes
when the food approaches, and prevents  its entrance.
The back-mouth having received the food, contracts, and
forces it over the closed valve of the windpipe down into
the gullet.
   The  gullet is a tube that  passes down through the
chest and opens into the stomach.  It is composed of
muscular fibres.   The upper fibres of the gullet contract
upon the food within  them, and force it down a little,
and the fibres beneath them, contracting in succession,
give to the food a continuous downward motion until it
enters the stomach.   The stomach is a large bag, capable,
in a grown person, of holding about three pints.   It is
placed beneath the diaphragm, somewhat  to the left, in
the upper part of the abdomeen.   Its right portion is
beneath the left portion of  the liver.  The stomach has
two openings, one on the left leading into it from the
gullet, and  another  on the right leading out of it into
the small intestine.
    Around each opening there is a muscular ring, which,
by contracting, closes  the  passage, and  never relaxes
except when something  is either to be forced  into the
stomach or forced out it.  The muscular ring on the
right is called the  pylorus, a Greek term for a  door-
keeper.
    It is a little lower than  the ring on the left, and the
stomach hangs between them.  The stomach is covered 
                         30
with two coats of muscles, the one running lengthwise,
and the other around it, and these, by contracting, dimin-
ish its size in every direction.   Its inner lining, called the
mucous membrane, is very thin, and is arranged in num-
erous folds, which greatly enlarge its surface.   This is
everywhere pierced  by more  than a million of small
tubes, each having branches, and every branch a group
of little bags.
   In contact with  these is a  network of blood vessels,
from which they obtain mucus to give a smooth surface
for the rolling  of the food.  In addition to this, over
the whole surface of the  mucous membrane, little fibrils
jut out like  short threads, so many and so close as to
resemble the delicate nap of velvet.
   Within these fibrils there is a network of blood ves-
sels, from which a fluid is secreted,  clear  as spring-water.
This liquid is called  the  gastric  juice, from  gaster,
a Greek term  for the stomach.
   The gastric juice converts the food within the stomach
into a grayish fluid, sligthly sour, and slightly sweet.
   This fluid is called chyme.
   This change in  the nature of  our food is called its
assimilation, which  means  the act  of making one thing
like another.   Thus the  conversion of food into chyme,
is called its assimilation to chyme, and the successive
changes which chyme undergoes before it is converted
into the tissues of the body, are but successive assimila-
tions.   In fact, the sum  of all the changes experienced
by the food from the time it enters the  stomach until it
becomes flesh, is called its assimilation to flesh.   Let us
now see the mode in which the food is submitted to the
action of the gastric juice. 
31
   There is  a contraction of the stomach about one-
third of  its length from the right extremity.   The por-
tion on  the  left of  this contraction is  several times
larger  than the portion on the right.  It is only in the
left portion that the unassimilated food is contained.
   There it is arranged in a# globular mass, the outer
layer consisting of the food first eaten,  and the  next
layer of the  food next  eaten, and so on to the centre,
which  consists of the food eaten last.
   When the food has been thus arranged, the capillary
vessels within the fibrils become loaded with blood, and
from it the gastric juice is secreted and poured into the
stomach.  At first this  juice produces  no  apparent
change upon the food, big: soon the  outer layer slowly
softens, until, losing its texture, it is completely dissolved.
The muscles  then contract upon this softened layer and
carry it toward the  pylorus.   Then, in like manner, the
next layer of food is  dissolved in the same way,  and
removed to the same place.
   Thus the  process goes on until all the food is con-
verted  into chyme.
   In its action upon the food the gastric juice is aided
by the muscles of the stomach, which, by their alternate
contraction and relaxation, compress it in various ways,
and give it a sort of churning  motion.  As soon as the
chyme, by its gradual accumulation in the right portion
of the  stomach, amounts to two or three ounces, a series
of actions takes place, of which the  following is the
result.
   The small end of the stomach, contracting behind the
chyme, forces it toward the pylorus,  which relaxes and
suffers it to pass into the small intestine. 
32
   The pylorus  then  contracts,  and the small end  of
the stomach relaxes, and they remain so until the same
quantity of chyme again accumulates, when the same
motions are renewed with  the same result.  Thus the
process goes on until  all  the  chyme resulting from
the dissolution of the food is driven into the small in-
testine.  I have said that our food, by the action of the
gastric juice, is converted into a different substance with
different properties.
   This, however, is true only of the  solid portion  of
our food.  The water which we drink, whether it is pure
or whether it has other substances dissolved in it, is not
acted -upon  by  the gastric juice, but is absorbed, un-
changed,  into  the  veins of the stomach, where it is
mingled with the blood.   Until • this  absorption takes
place, the gastric juice will not be secreted, and, of course,
the food will not be assimilated.  Now, the water will
not be drawn into the veins unless the body needs it, and
this need will be indicated by the  sensation of thirst.
If, then, we drink when we are not thirsty, the water will
remain some  time in the stomach and delay the assimila-
tion of our food.  This  is  one  reason for drinking no-
thing but pure water, for ordinarily we will not drink
water  when  we are  not thirsty, but if something  be
added to  the water to make it agreeable, we will drink
for the mere pleasure of drinking.   It is also a reason
for taking food in  the solid rather  than  in the  liquid
form, for in  the latter  case  we will be liable to take
more water than the body requires.  Thus much of the
liquid food.  Let us turn now to the solid food.
    We have seen that the assimilation of the solid food
is accomplished by the gastric juice.  Of  course, then 
33
the greater the quantity and the purer the quality of
the gastric juice, the more food will it be able to  as-
similate.
   We  have also  seen that this juice is secreted from
the blood, and hence its  quantity and purity will  be
affected by the state of the blood.  But the condition
of the blood, as we have noticed before, is indicated by
the condition of the mucus and saliva of the  mouth.
If, then, the mucus and the saliva be impure, the gastric
juice will be deficient and depraved,  and hence will be
able to  assimilate imperfectly only little food.
   It hence follows, as a natural consequence, that when
the secretions within the mouth have a bad color, and
unpleasant taste, we should not eat.
   Should we  neglect this warning, our food will  be
mixed with  impure  saliva, and hence will  enter the
stomach in an unfit condition.   It will then be acted on
by a small quantity of bad gastric juice, which  will as-
similate imperfectly  only a portion of the food.
   And what becomes of the remainder 1
   It acts in the  stomach as it would do in any other
damp warm place.
   It putrifies  and sends forth  poisonous gases, which,
enlarging, press against  the fibres of the stomach, and
injure in various ways.  The consequence is, that either
there is a backward action of the muscles of the stomach
and gullet, and the foul mass is vomited forth, or else it
is forced into the small intestine, causing the bowel com-
plaint.  This shows the folly of trying  to gain strength
in sickness, by eating food, and proves the benefit  of
fasting, for it is not, no, it cannot be proper, to  burden
the system with the assimilation of food when it  is over-
      3 
34
tasked in endeavoring  to  purify the blood.   Even  in
health we should be careful not to  cat  more than the
body requires;  for, if we do, then either the food will
be imperfectly  assimilated  from the want of sufficient
gastric juice, or else the  stomach will receive  more
than its share of blood and nervous energy, and thus rob
the other organs of their  share, or else only a part of
the food will be assimilated, and the  rest  will breed
disease.
   But how can we know when we have eaten exactly
enough 1  Simply by eating only when  we have an ap-
petite, and by ceasing when we have  satisfied that ap-
petite.
   This can easily be observed if we will only eat simple
food:  but if we season our dishes highly to pamper the
taste, we  will eat for the  mere pleasure of eating.   Thus
simple food as well as pure  water is the  best nutriment
for man.   This  fact is proved by experience, as well  as
prescribed by theory; but, though all acknowledge it, few
will  practice it, for  most men  choose present pleasure
even at the expense of future pain.
   Having said thus much  of the stomach, we will now
proceed with the process of nutrition.
   The chyme,  as we have  noticed, is poured from the
stomach  into the small intestine.   The small intestine
is a narrow tube of great length, being about four times
as long as the body.   It is  folded many times in various
ways  and ends, as we have already said, in  the lower
part of the  right side of the abdomen, where it com-
municates through a valve with the  large intestine.
The small intestine  has two layers of muscles, the one
running  lengthwise  and the other around it, which by 
35
contracting, make it both shorter and narrower.  Around
these muscles, as well as on the outside of every internal
of the body, there is a thin shining membrane.
   This  is  everywhere  pierced  by  millions of  little
tubes  communicating  each with  a little  bag.   From
every one of these exudes a  thin, watery fluid, called
serum, which lubricates  the outer  surfaces  of all the in-
ternal organs, and thus  enables them to slip over each
other without  injury.   The serous membrane,  which
surrounds the  small  intestine, extends behind it like a
riband.
   This  flat  appendage, with its  two layers of  serous
membrane, is called the mesentery.   Between the layers
of mesentery,  there are  nerves, and arteries, and veins,
and other vessels, passing back and forth.
   The mesentery is fastened to  the spine, and thus
keeps the small intestine in its place, and  yet allows it
to move freely in all directions.
   The small intestine, like the stomach, has an internal
lining, which is arranged in numerous folds, so as greatly
to enlarge its surface.   Millions of small glands pierce
this coat, and pour out mucus to lubricate its surface.
Millions of little fibrils also project from it, and  secrete
from  the blood a fluid something like the gastric juice.
In the upper  part of the  small intestine a tube  leads
into it on the left from the pancreas.
   It is in this same part of the small intestine that the
sail tube leads into it from the liver on the right.
   'The pancreas is placed in the upper part of the abdo-
men behind the lower part of the stomach.   It is a tube
with  branching tubes, and branches  of branches, each
ending in a little bag. 
36
   Every one of these tubes and bags  is brought into
contact with branching nerves and arteries.   From the
blood of the arteries they secrete a fluid called the pan-
creatic juice, and pour it into the small  intestine.
   The pancreatic juice looks like saliva, though it has
very different properties, and aids the intestinal juice in
changing the nature of chyme.
   Let  us now proceed with the process of nutrition.
The  chyme received from the stomach, being acted on by
the intestinal juice and the pancreatic juice, is converted
into  a fluid that looks somewhat like milk, though it
possesses very different properties.   This white fluid is
called chyle.   In assimilating chyme to  chyle, the intes-
tinal and pancreatic juices  are  aided by  the alternate
contraction and relaxation of the muscles of the small
intestine, which give it a sort of  churning  motion.
   It is a matter  of dispute among physiologists whether
or not the gall and the bile aid the other juices  in as-
similating chyme to chyle.
   Those who maintain that  it does, urge in its favor an
experiment several times repeated in France, in Germany,
and in England.
   The abdomen of an animal was cut open, and its
gall tube was tied, and then it was fed.   Some time after
it was examined,  and no chyle was found  in the small
intestine, nor in the vessels that branch from  the small
intestine, and hence it was concluded that the gall and
the  bile are essential to the assimilation  of  chyme.
Now this  does not seem to be a fair conclusion, for the
wound inflicted in cutting the animal open, and the fever
resulting from it, would  of  themselves  have  prevented
the assimilation of chyme, even if the gall tube had not 
37
been tied.  If the experimenters had cut open two ani-
mals instead of one, and had tied the gall tube of one,
and not of the other, and after feeding, had found chyle
in the one whose gall tube was not tied, and found  no
chyle in the other, then the experiment would have been
conclusive.
   But  this was not done, and hence  the  experiment
affords no proof that the gall and the bile are necessary
in converting chyme into chyle.  But it may be asked,
Why are  these fluids poured into the upper part of the
small intestine if they afford  no aid in assimilation'?
To this it may be  answered,  that  they dissolve fatty
matters and thus prepare them for assimilation, and also
delay the putrefaction  of waste  matters  that  pass
through the small intestine.
   These  actions  are  very different from  assimilation,
and yet they are essential to bodily health.
   Having examined the arguments of one side, I will
now turn  to those of the other.  The fact that the gall
and the bile are secreted from the dark red blood, while
the gastric, the intestinal, and the pancreatic juices  are
all secreted from the bright scarlet blood, is urged as a
proof that the former are not made for the  assimilation
of chyme, but for the purification of the blood, and
hence, that  though they may enter  the small intestine
partly to  dissolve  fatty matters and delay putrefaction,
it is mainly  for the purpose of  purifying the blood.
   Such is the first proof.
   And now for the second.  The bile and the gall in a
healthy state of  the system are never found in the stom-
ach.  Whenever, by the backward action of the small
intestine,  and the relaxation of the pylorus, the gall and
     3 
38
the bile are forced into the stomach, the stomach recog-
nizes  them  as  enemies and immediately proceeds to
expel them.
   It either drives them back to the place whence they
came, or else, aided by the gullet, it vomits them forth.
Now this is not the  case with either the intestinal juice,
the pancreatic juice, or the chyle.
   The stomach can bear their presence, and makes no
violent effort to remove  them.
   Now why is the  stomach  content with these and not
with those1?
   Is it not because it is endowed by its Creator with the
power of discriminating between what is good  for the
body  and what  is injurious to itl
   If so, then have we not sufficient proof that the gall
and the bile are noxious fluids, instead of assimilating
juices, and that they are secreted from the blood for the
purpose of purifying it, and of being removed from the
body.
    And here let me remark, that the presence of an
emetic in the stomach  causes a backward action of its
muscles, which is often propagated to the small intestine.
Thus the gall and the bile are forced into  the  stomach,
which, aided by the gullet, vomits them forth  together
with  the emetic.
    When this  happens, the patient naturally supposes
that the gall and the bile were in the stomach before
the emetic was swallowed.  If he acts on this supposi-
tion, these noxious fluids will continue to be given off as
often as the emetic  is administered, until death  ensues,
as has sometimes been the case.
    Let us return now to the process of nutrition. 
39
   We  have said that the assimilation of chyme is ac-
complished  by  the  intestinal  and  pancreatic  juices.
These act at first upon the chyme in the  upper part
of the small intestine, and convert a portion of it into
chyle.
   This fluid is at once absorbed by  the coats of the
small intestine.
   What now becomes of the undissolved chyme 1  The
muscles of the small intestine above the chyme contract
upon it and force it down a little.
   Then additional intestinal juice is  secreted, another
portion of the  chyme is converted into chyle, which is
absorbed by the small intestine.  Thus the  continually
diminishing chyme is continually being forced down the
whole length of the  small intestine, until the balance
of it approaches the large intestine.
   Here, instead of chyme, we have  the portion of it
that cannot be dissolved.
   This consists of the bran of wheat and corn, the skin
of seeds, and fruit, and other indigestible matters.
   These pass through a valve into the large intestine,
where they are mingled with the  impurities that have
been secreted from the blood.
   Thus we see that there is a provision in  the body for
the  purpose of separating the nutritious portions of  our
food from the innutritious.
     Hence  we  find  in most  articles of food  a large
 quantity of  waste material.
    If this were  not  the case  we  would soon become
 diseased.   I will now give additional  proof of the fact,
 that if is beneficial to health to  have  innutritious mat-
 ters mingled with our food.  In order that the muscles 
40
of the stomach may churn the  food to the greatest ad-
vantage, it is  necessary for them to be  filled out with
a certain bulk.  If in order to obtain  this bulk we eat
a large quantity of pure nutriment, the gastric juice will
not be able to assimilate all of it, and  hence there will
be disease.
   But  if we  eat  food that has much  waste material
mingled with it, we can take little nutriment, and  yet
have sufficient bulk.  In addition to this, the innutritious
materials  will cause the food to be spread  over large
space, and hence the  gastric juice  can  act  on  it to a
better advantage.
   In accordance with these views, we find that, in sum-
mer time, when we do not need as  much nutriment as
in winter, we have fruits, and vegetables, which usually
have great bulk combined with little nutriment.
   This is the proper place also to remark, that ever
since the  time when machinery was so perfected as to
separate the bran from the wheat, constipation has been
a general complaint,  while before that time  it  was
scarcely known.  Such is the penalty we are obliged to
pay for disregarding the laws of health.
   We will  now proceed with the process of nutrition.
In describing  the assimilation of chyme to chyle,  we
have said that the chyle, as soon as it  was formed,  was
absorbed by the coats of the small intestine.
   Let us now look  at  the vessels which receive the
chyle and pass it onward.
   In the inner coat  of  the small  intestine  there  is a
network  of  small  vessels.  From this network small
tubes  arise that unite into larger tubes, and the.se  into
still  larger.   The last pierce  to the  outside  of  the 
41
mucous coat,  and pass some distance between it and
the muscular coat.  At length they pierce the muscular
coat, and run between it and the outer coat of the small
intestine, until they reach  the mesentery.  The mesen-
tery, as we have already stated, is simply a flattened con-
tinuation of the serous membrane of the small intestine.
The tubes  then pass between the layers of the mesen-
tery, when they unite and form a network  of vessels.
From this network arises tubes that branch, and enter
a set of glands, where they form a network, and bend
hither  and thither, and are interwoven with nerves and
blood  vessels.   The  tubes,  after going out of  these
glands, again unite into larger tubes the same  in number
as before.   These tubes again branch and enter another
set  of  similar glands, where they are interwoven with
nerves  and blood vessels, and after leaving these glands
they again unite and form larger tubes, which leads to a
pouch  in the  upper part of the  abdomen.   From this
pouch, called the receptacle of the chyle,  there is a tube
that rises through the chest, and communicates with a
vein at the root of the neck.
   The vessels that convey the chyle from the small in-
testine to the receptacle of the chyle, are called lacteal
vessels, and the glands  through which  they pass  are
called lacteal glands.   They  are so called from lac, the
Latin term for milk, because the chyle resembles milk.
When  trie  chyle is absorbed by the mucous coat of the
small intestine, it enters the la'cteal vessels along which
it goes, and passes through the lacteal glands.  Within
these glands the chyle is brought into intimate contact
with the blood, which changes  its nature  by remov-
ing  some of  its elements,  adding  others to  it, and 
42
altering  the arrangement of those which it retains.
   Within  these glands,  also, those little circular flat
bodies are formed which give  the scarlet color to the
blood.  They do not, however,  obtain this color  until
they have entered the lungs.  These bodies are so small
that it takes five thousand of them laid side by side to
extend an inch, and yet each of  them contains another
cell which has a nucleus within it.
   Thus we see  that  the chyle is  assimilated  by the
blood within these lacteal glands, and after going out of
them is a different fluid from what it was  before.
   Then  the  assimilated  chyle  goes to  its receptacle,
whence it rises through the chest and enters the veins.
Thence the  chyle, together with the lymph, and the dark
blood, is sent to the lungs, where it  undergoes another
assimilation.
   The air  of the lungs, by its action upon the white
chyle, the clear lymph, and the red blood, giving to  them
electricity, and oxygen, and removing from them carbon-
ic-acid gas and noxious vapor, changes their nature, and
forms them  all into a uniform fluid, the scarlet blood.
   And now the scarlet blood  itself must undergo an
assimilation.   This is done when it enters  the tissues of
the body, and destroys a  part of them.   Then out of
the scarlet blood, new flesh is formed to counterbalance
the loss of the old, and this is the final assimilation.
   Having thus traced the changes which the*food un-
dergoes in  the body, let  me remark, in the first place,
that since the juices which  assimilate the chyme are
secreted  from the blood, if  the blood be impure  we
will have depraved or deficient chyle.
   In the second place I will observe, that  since our 
43
flesh is formed from the blood, if the blood be impure
we will have deficient or unhealthy flesh.
   Thus close is the connection between a healthy body
and pure blood.
   In the third place let me remark  upon the change
which the chyle undergoes in passing through the lungs.
It is not until it is exposed to the  action of the air that
it loses its white color,  and assumes a scarlet hue.   And
without scarlet blood there can be no healthy blood, and
this  change  of  color  will be  only partial, unless we
breathe pure air.   All the  other  assimilations of our
food might be perfect,  and still they would be counter-
balanced if we should  inhale a foul atmosphere.  How
then is it that so much importance  is  attached  to
the quality of our  food, and so little to the purity of
the air'?
   We eat ordinarily only three times a day, and not at all
in the  night, and can go without eating for several days.
Thus it is with our food.   On the other hand we breathe
day and night,  eighteen times a minute, and if we stop
it for three minutes we will  die.
   Would it not then be supposed that we would be
more careful to  breathe pure air than to eat good food 1
And yet we  devote most of our attention to the former,
and scarcely any to the  latter, and  this, too, when in
order to obtain the required nutriment, we must exercise
muscles and brain day  after day, and year after year;
whereas, there is an ocean of pure air covering the whole
globe  to the height of fifty miles  above our heads, that
only needs to be led into our apartments while the foul
air is forced  out.
    Since, in the former  part  of this lecture, I pointed 
44
out one way in which an ordinary apartment could be
ventilated, and since further discussion would detain us
too long, I shall say no more on the subject.   I shall be
satisfied if I have given my hearers even a faint idea of
its overwhelming importance.
   I think, my hearers, that even from  the imperfect
description of the human body which I have given, you
may obtain some  conception of the infinite  wisdom
employed  in its construction.  It is  a  marvellous  in-
stance of Almighty power, and, in union with the soul, is
the crowning work of creation.
   We, who are subject to  sorrow and  disease, cannot
conceive of the glorious beauty that enrobed  the forms
of our first parents as they walked in happiness and
purity in the garden of Eden, when angels were their
guests, and God was their friend.
   Though  they had  motions and sensations like our
own, though like us they assimilated food  and breathed
the air, yet their bodies were gifted with the power of
resisting forever the inroads of disease and of death.
   And thus would it have continued had they  not dis-
obeyed  the  command of their Creator and eaten of the
fruit of the tree of knowledge.  This fruit was endowed
by the Almighty with the power of altering the consti-
tution  of the body, so that it would  gradually yield to
the elements of decay.  If, after eating of this baleful
fruit, they had  partaken of  the fruit of the tree of life,
then they would have obtained an antidote, and regained
their immortality.  But  this was not  to be,  for  the
Almighty drove them out  of the garden of  Eden,  and
placed at its entrance cherubim, and a  flaming  sword
which turned in every direction, to guard the way of the 
45
tree of life.   Over the scenes of sin, and pain, and sor-
row, that then ensued, angels would weep if they could
weep.  It touched the compassion of God.  No sooner
had He driven the unhappy pair from the gates of Par-
adise, than He turned their despairing gaze to Him who
should bruise the  serpent's head, the promised seed of
the woman.
   And who was this 1  None other than his own eter-
nal Son, who was to  assume our nature in conjunction
with  his  divine nature.   In the  course of revolving
years, after a guilty race had all been drowned by the
deluge, and  none, save eight righteous, remained  to  re-
people the  globe; after clearer  prophecies had been
promulgated, and a preparatory covenant  had been  in-
stituted, the Virgin Mary was indicated as the destined
woman whose seed should bruise the serpent's head.
   It was through the overshadowing influence of the
Holy Ghost upon her, that she conceived an infant who
was both God and man. Then it was that to his everlast-
ing, Almighty, all-wise, boundless divinity, Jesus Christ
joined his new-conceived mortal, feeble, ignorant, limited
humanity.   Such was the mysterious Being who was born
of a woman, and was laid in a manger.  Well, then, might
the angels, with songs of  holy joy, announce  it  to the
shepherds of Bethlehem, and well might a meteor, gleam-
ing in the sky, guide the wise men of the East  to the
destined king of the Jews.
    Although our Saviour, being born of a woman, pos-
sessed a soul that was subject to sorrow, and a body  ex-
posed to disease and death, yet, through the influence
of  the Holy Ghost,  he was not  conceived in iniquity.
Hence it  was, that though he suffered and died, it was 
46
for the sins of others, and not for his own.  It was to
atone for our sins that the Son of God  underwent his
lowly birth, and suffering life, and painful death.
   Does  it not, my hearers, indicate the inconceivable
value of the  human body, when even the Eternal Son
of God did not disdain to  unite it to his  divine nature %
Would God have become  -man if the body is so worth-
less as many deem  it %  Surely not,  and therefore the
health of the body should be the subject of our thoughts
as well as the health of the soul.  And  the failure of
the one will  subject  us to temptation  as well as the
failure of the other.   It was when  our  Saviour's  body
had been reduced by a superhuman  fast of  forty days,
that the  devil urged  him  at first to prove his divinity
by converting stones into bread, and afterwards to cast
himself from  the wing of the temple that  the angels
might sustain him, and lastly,  to worship the tempter
that he might possess the glorious kingdoms beheld from
the mountain top.   Such  were the temptations, but
Jesus overcame  them all,  and bade his defeated adver-
sary to worship  the Lord  his God,  while angels  came
and ministered unto the conqueror.
   It  was while  he was in the body that Jesus  endured
that sore agony in the garden of Gethsemane, when he
did sweat, as  it were, great drops of blood, and prayed,
" Father, if thou be willing, remove this cup from  me:
nevertheless, not my will, but thine be done."   And the
Father listened  to his prayer, and an angel came down
from Heaven  to strengthen him.
   It  was his body that was betrayed by  one of his own
disciples, seized by his enemies,  condemned in the judg-
ment  hall, was beaten with rods, crowned with thorns, 
47
and spit upon.   It was the agony of his body hanging
upon  the accursed cross, beneath a frowning heaven,
above a mocking world, that made him utter that bitter
cry, " My God, my God, why hast thou forsaken me."
   It was at the parting of the soul from his body, that the
earth did quake and the rocks rent, and the veil of the
temple parted in twain, and many graves of holy men,
opening wide, released  their victims  freed  from death,
and  the Roman  centurion, listening  to the voice of
conscious nature, cried aloud, " Truly, this was the Son
of God."
   It was his body, pale, distorted, and bloody, that was
lowered from the  cross and borne to the garden, and laid
in the  silent gloom of the new-made sepulchre, hewn out
of the solid  rock.   It  was his  lifeless body  that was
guarded by Roman soldiers until the dawn of the third
day, when an angel came down  from heaven and rolled
away the stone from the door of the sepulchre, and sat
upon it, and glared, like lightning, upon the  warriors,
who became  as dead men.
   It was his body which his soul, returning from Para-
dise, rejoined in the grave.  And then his wounds were
healed, and his blood circulated,  and his lungs breathed,
and  color came to his cheek, and strength to his limbs,
and  he arose from the grave forever triumphant over
death.
   The body of our Saviour, after his resurrection, was
the same that he  possessed before his death, though it
was  freed from subjection to disease and decay.
   This is proved by the fact  that his raised body re-
tained traces of the wounds he had received during the
crucifixion.  It was only after feeling the prints of the 
48
nails  in  the Redeemer's hands, and the mark of the
spear in his side, that the doubting Thomas believed in
the reality of his  resurrection, and exclaimed, " My
Lord  and my God."
   It was his body that from the top of  Mount Olivet
rose to heaven, while half a thousand disciples gazed
upon  his lessening form until an intervening cloud hid
him from their sight.   It was his body that continued
to rise, passing world  after world of  countless  creation,
until  he  entered the  gates of heaven, amid the halle-
lujahs of archangels,  and of seraphim, and cherubim.
It was his  body that  sat upon the  right hand of the
Father, where he received the  adoration of angels, and
wielded the sovereignty of the universe.
   It  is his body that  still continues in heaven pleading
for his people, presenting  their prayers to the Father,
and sending down upon them the Holy Spirit.   It  is in
his body, once humiliated, now glorified, that  he  will
come  down from heaven  and redeem his people from
their  enemies, and restore to them their  beloved  city,
and reign over them  forever.   Such is  the exaltation
imparted to the human body by Jesus Christ.
   I would now remark, my hearers, that our Saviour's
resurrection is a pledge of our resurrection.
   As sure  as Jesus rose from  the sepulchre with the
same  body  which  was crucified, so  sure will  we rise
from our graves with  the same bodies which shall  part
from  our souls.  This, many will declare to be impos-
sible,  because our bodies will be decomposed, and their
elements will rise in the air,  and fly on the wings of the
wind, and sparkle in the foam of the ocean, and form a
part of the solid globe, and enter  the bodies of plants, 
49
and of animals, and of successive generations of men.
    They deem it impossible, even for God, to trace the
countless  atoms of millions of men in their  intricate
wanderings, and to restore them to the same bodies from
which they came.
    But who shall dare to limit the power and the wisdom
of God %
    Not until we have sounded to its depths the  skill dis-
played  in the construction of the human body, should
we presume to measure the power of Him who holdeth
creation in the hollow of his hand.
    It is too much the custom of the present day for man
to boast of the attainments of science, and to  measure
his puny arm against the arm of Omnipotence.
    But what is the amount of knowledge gathered from
a thousand sources in all departments in science as com-
pared with what is unknown ?  It is but as a few drops
of  water  out of the  boundless  ocean.  Such  is my
answer to the first objection.  But there is another, and
a stronger objection.
    It is urged that the dead bodies of one generation
have been  formed in part of the dead bodies of pre-
ceding  generations, and that the  particles  which are
thus common  to several, cannot be restored to all, and
that,  consequently,  our bodies  after  the resurrection
will not be the same as before death.   In reply to this
I remark, that it proceeds on the supposition  that the
identity of the body cannot be  preserved unless all its
particles are restored to it; but this cannot be  allowed.
The body during life is continually changing; every mo-
ment it is losing old flesh and receiving new,  and yet,
during  all this  time, it is the  same body.  In  order,
       4 
50
therefore, that the body, after the resurrection, be  the
same as it was during  life, it is only necessary for  the
elements of the  old body,  which are not common to
other  bodies, to be gathered together as a nucleus and
incorporated with new  matter.
   This was not  necessary in the  case of our Saviour,
for  he was raised from  the dead before his body had
yielded to  corruption; but  such  must  have been  the
mode  in which those saints  were  restored to life, who,
after the resurrection  of our Redeemer, came out of
their graves and went into the holy city, and appeared
unto many.
   Their bodies must have been dissolved, and therefore
the earthy particles remaining  in their graves must
have been incorporated with new matter when they were
rebuilded into immortal bodies.
   As it was with them, so shall it be with  us on that
day when the archangel's trump shall sound, and call us
forth to life and immortality.
   Having thus shown the identity of the body in this
world and the next, I will next remark that they closely
resemble each other.   Of this our Saviour himself fur-
nishes a remarkable proof.  When our Saviour appeared
for the first time before his assembled disciples, after his
resurrection, and said, " Peace be unto you," they were
affrighted, supposing him to be a spirit.  It was  not
until he had said unto  them, " Behold my hands and my
feet, that it is I myself: handle me and see ;  for a spirit
hath not flesh and bones as ye see me  have," that they
were reassured and believed him to be the  risen Lord.
It is further stated by St. Luke that he showed them
his hands  and his  feet, and ate a piece of a boiled fish 
51
and of an honeycomb.   Thus we see that our Saviour's
body possessed  traces of the wounds which it had re-
ceived during the crucifixion, and that  it assimilated
food just as it did before his death.
   Thus our Saviour in his glorified humanity resembled
Adam and Eve in the garden of  Eden.  And such, we
have every reason to  believe, will be our condition after
the resurrection.
   With these glimpses of a glorious theme I must close.
   With you I have looked into the mysteries of the
body, have glanced into the  garden of Eden, have wit-
nessed the  chief events of our Saviour's life, have seen
him  die upon the cross, rise from  the  grave, ascend to
heaven, and sit upon the throne.
   We  have also looked  forward  to the time when he
shall come down to redeem his people.   And oh! may it
be our lot then to meet his approval, and share with him
those joys which " eye hath not seen, ear hath not heard,
neither  hath it entered the heart of man to conceive." 
 
A LECTURE
ON
THE HUMAN BODY.
BY JOHN A. PAESONS.

       U*to grck:
PUBLISHED BY C. SHEPARD & COMPANY,
   No. 15 2 FULTON STREET.
        1854. 
 
 
 
 
NLM032054271