New-York daily tribune. [volume] (New-York [N.Y.]) 1842-1866, 1850-11-28
VENTILATION A LECTURE
BY JOHN H. GRIsCOM, NJ D.
iRcnorted fnr the Tribune

A large and highly intelligent audience Assem-
bled in the lecture room of the Brooklyn Female
Academy, on Tuesday evening, 10 listen to lee
ture by JOHN H. GRIscoM, Ventilation, who,
being introduced to the audience, spoke substan
TALLY as follows Ladies and Gentlemen-In in
Producing this subject l must throw myself upon
your kindness in regard to the nature of this sub
iect, and the multiplicity of the points which it
presents for discussion But with your indulgence
I will endeavor to point out to you its prominent
points. If any Of you were asked the question
upon what do we live Your first answer would
be, of course the food which we eat. The air
which we breathe would scarcely enter your
mind.
shall show, however that not only is the food
which we eat e secondary matter, in relation TO
our subsistence, bat without the atmosphere the
food itself would be useless. You all kno W what
the food is Tor it is converted finally into blood
The meat which we eat and the water which we
drink descend into the stomach and undergo vital
operations which change their condition and color,
and finally in that new condition, it is passed
from that organ and soon finds 1t way into the blood
The food, after digestion, is of homogeneous sub
stance, and of whitish color The color OF the
blood as you all know, ia red and vermillion
Now, you viii perceive at once, that before this
food can be converted into blood it must neces
sarily undergo many processes, so as to be able
to nourish the body. Now, what is this physical
change This is what | wish to direct your at
tention to this evening; or, as the programme
calls it, " Ventilation Now, how long can you
go without eating Perhaps day, without great
discomfort; possibly you may live a week with
out food. But how long you exist without
air In five minutes, if air is entirely shut off,
life will cease Respiration is the last act of dl.
gestion. Digestion is the act OF converting food
into blood. Between the act Of taking food into
tbo md digest
| i've organs, there is a great operation going on ;
but the most important of all these changes which
20 to render the food blood is that of respiration
| propose to direct your attention, first, to the
mechanism, and second to the chemistry OF res
| plratlon:
First, you will ask, how does the air come in
contact with this food? 1t is received by organs
which appropriate it to its proper use Next, you
may ask, how does the air get into the chest :
The common idea, that the chest opens and the
air rushes in, is a mistaken suppostlon There IS
no more familiar mode of expressing this opera
ton, than by comparing it to pair of bellows in
working which vacuum is created within, and
! the air rushes in and fills that vacuum. This IS
very simple operation, but it is precisely the same
as mechanical respiration. Next how is the chest
enlarged This is done by set of organs called
the muscles of respiration" The chest is com
posed of ribs-twelye on each side. Beside the
motion of the ribs which give this movement OF
hearing to the chest, there is very large increase
! by peculiar muscle called the :" floor OF the
chest
The speaker here went on 70 describe the eper-
alton of the lungs showing that they have a duty
to perform toward swelling out the chest He
next spoke of the capacity OF the chest, remark
ing that it's capacity depends in q great measure
upon the habits OF the individual some having
much fuller chests than others; and those are the
best off who have the largest chests, as they have
the best lungs.
He continued: {" It is the easiest thing in the
world to contract the chest, but it is not so easy
to c1pand it. But it can be enlarged greatly by
cultivating the muscles lying over the chest
| Twelve pints of air is the amount which the chest
will contain the amount which may be taken at
a single respiration is another matter. Public
singers Including, of course, chimney sweeps and
| charcoal mem will inhale eight or nine plnts Of
air at a single respiration. cannot too earnestly
exhort you to cultivate the expansion of the chest
as a means of increasing health and happiness
There is one other point to which wish to di-
rect your attention, in relation to the mechanism
OF the lungs; it is the heart. This is very es-
sental organ to the function of respiration. You
| doubtless all know where the heart is situa-
ted. 1t lays very near the center of the chest,
| against the left ribs. tt is only the pulsaton Of
the heart striking against the ribs which creates
the beating. The heart pusates about - times
per minute. Night or day, it is ever in motion:
Although it it not essential to the nOurlshment OF
the body, yet, it is important to maintain the
flows from the heart through the body, and thas
gives it nourishment. When this blood has flow
ed through the body and comes back to the heart,
it is of entirely different color from when it left
it. 1t carries with it, life, health vigor; it brings
back O totally different material What now be-
comes of it 1t is thrown back through the lungs.
There must, then. be some intimacy between
the circulation of the blood, and the heart There
are 70 ounces of blood pass through the heart per
minute, and 25920 respirations every "a hours,
and "a hogheads of blood pass through the heart
in the same time. And next as to chemical res
piration. What is the mpurity in the blood which
the atmosphere is required to remove! That in
gredient of the atmosphere which produces this
effect is the oxygen. The standing temperature
of the body is % degrees, whether in frozen Lap
lands or the sunny South
The speaker here tried several experiments to
show that carbonc acid gas is degenerated in the
lungs, and thrown off into the open air, remarking
that this is the material often found IN wells
which have been long closed. He then took q jar
containing oxygen gas, and tired several eX-
periments, illustrative of the difference between
oxygen and carbonic gass He remarked that we
eXhale about eight ounces OF carbonlc gass every
"a hours. Oxygen, said he, is non influential,
inert substance; it is poisonous substance, al
though you sometimes drink tin soda water. But
the stomach has the power OF separating bad from
good substances, while the lungs have no such
property. There is selecting power In the
lungs as there is in the stomach. AS to the guam
tity of air which is necessary to maintain life,
there are various opinions. Some think it requires
four cubic feet per minute others say 20 feet; but
probably II cubic feet per minuets what is really
necessary. You may easily ascertain how much
air there is in any room where you are,
But, ladies and gentlemen the experiments
which l have shown, will enable you to under
stand the great necessity of charging the cap!acl-
ty of the chest so as to admit each inspiration
much air you can get into the lungs, You
you may get too much food into the stomach.
There is never any danger of producing anything
like Indigestion in the lungs Catherine Sinclair,
in one Of her works, truly remarks that " all the
joys of life are destroyed by being afraid OF the
SSntS s6R pg youF eyes to the