Hannibal journal. (Hannibal, Mo.) 1852-1853, 1853-02-17
From the Scientific Amtricdn.
:. ana u. fIissA unon Animal Life.

A very interesting lecture was deliv cred on
the l,h inst, by DR.. Griscom, at the New York
Mechanics Institute, on the "lnhuepce Of Air
in connection with Animal Life" The lecturer
commenced by saying that some Of them would
be surprised 10 hear that they lived at the bot
tom Of an immense ocean Of air fifty miles deep;
yet il was so, and the color Of this ocean, which
is called atmosphere, is deep cerulean blue. =
To perceive this color il was necessary 10 be
able 10 see at once the whole volume, and also
on calm and clesr day. for no color could be
perceived II seen IN small quantities, or when
there was either wind or haziness. In like
manner the color Of water could not be seen ia
small quantities, and was only perceptible where
there was a vast expanSe Of ocean. The air
was also substance capable Of condensation and
expansion. Its expansion was seen in the winds
by which ships were made to traverse the ocean,
and also in windmills. The tornado was anoih-
er phase Of IFS expansion, by which trees were
uprooted, and houses overturned, and was al
most equal to the power Of steam. The great
est weight OF the atmosphere was fifteen pounds
70 the square inch, and this weight presses on
every way, both upward and downward. To
explain the pressure upwards, the lecturer ex-
hausted the air out of large vase, which then
remained fast TO the plate on which it stood. but
on the air being let in il was easily removed
II remember, said he, being asked the question, IT
There is pressure Of fifteen pounds 20 the square
inch, the reason why we were not at once
crushed by the weight; but this is, as before
Explained, because the air presses in all direc-
tions with the same force, and hence there is an
equilibrium. This is a most important element,
and one which requires 10 be known, and also
that the air never presses more than fifteen
pounds to the square inch. The next quality OF
the air is elasticity. Press it SO as 10 make It
occupy smaller space than il otherwise would,
and then take away the weight, and 1t comes
back and occupies IFS original space. The lec-
turer then explained that in the air there were
two gases; one oxygen, which is that part OF the
atmos phere by which we live, and which is the
one fifth part; and the other nitrogen, which is
four -fifths Of the atmosphere. Oxygen sup
ports life and combustion, and nitrogen restrains
lis effects and dulls lis operation. The quantity
of air which person consumes depends in a
measure OH oneself, and by training can be made
more or less. The tailor and shoemaker take
little in comparison ~i;a :hc !=tr-er. end 'he
public speaker and singer, or those who cry
commodities 10. sale through the streets.
: man in good health makes eighteen respiraiions
, in minute, and in twenty -four hours consumes
fifty one hogsheads Of the air. As the oxygen
: which supports life is so small we ought to be
very particular how we permit other gases to
mix with it and vitiate it. The blood when il
enters the lungs, is black, but when the oxygen
acts upon il it becomes red, and sends it through
the veins TO impart life and animation. This
black blood is produced by carbon and imparts
) the blackness which we see in the face Of per-
sons who lose their lives by sullocation, because
the oxygen was not allowed 10 reach the lungs
TO purify it. When we send out the air from
the lungs, we do not send il in the same manner
as we inhaled it, for when eXhaled it is as dead
: ly a poison as arsenic or corrosive sublimale.-
The lecturer showed this by experiments, ant
' filled vase with his own breath, in which 4
e lighted candle would not live. 1t was such all
as killed persons who went down into wells II
a the country, or who died when pan OF charcoa
Is was placed in room. The danger OF taking
: lmpurc matter into the stomach was not so grea
as into the lungs, for the stomach had power Il
$ eiect impurities which the lungs had not. BE
Il side the impure air which we exhale there ar
e 9 800 pores on every sqaure inch Of the surfac
v of the hody, and 10 body Of large size ther
l. are 2, 500 square inches; and these multiplied
% make T. 900 600 of pores. There is sort o
d drainage pipe in the body, which sends out mat
e ter as well as gas, and this pipe is calculated a
y ;wcnty-eight miles long. The particles of mat
eter which are sent out. and which do not DIS
> solve are so numerous, that IN China, where III
N houses are low aud great many persons are =
l. the habit Of assembling in one room, II has bee
D. discovered that, after fifteen or twenty year.
these particles adhere 10 the ceiling of the rooms
'e that the farmers will contract 10 put up ne'
II ceiling il they are allowed TO take down the ol
one, SO valuable has il been found iof manure.
N