New Orleans Republican. [volume] (New Orleans, La) 1867-1878, 1876-06-07
Campoaiflsn of Air.

The most beautiful analyeis which Liebig
invented 10 that of air. TIE composition
Of the air was made known at tie end of
the last century. and then it wa shown to
proportions, the oxygen being about enc.
fifth end the nitrogen about four-ffths Of
the volume and nearly the same proper
tons by weight. But these proper ions
were not exactly ascertained, because it
was necessary to remove the oxygen ty
means Of complicated process of dedagra-
tion by mixing 1t with hydrogen, which Oc-
q ioBed certain lDperfecti0ns. These were
entirely removed BY the method which Lie
closed 1t in one of these tnbes, and then
brought in contact with it solution of pyro-
gallo acid in caustic potash. This pyrO
gallste of potash has very great avidity
for oxygen, and in short time absorbs the
whole Ut the oxygen contained in the tube.
In that tube We have quantity Of air, and
my assistant has introduced quantity of
pyrogsllate Of potash. and you sec how
gradually the absorption takes place. The
gas becomes Diminished and The gas rises
in the tube accordingly, and out of the
original Eve parts there remain only four 1T
the conclusion of the experiment. The
whole of the oxygen 10 absorbed without
leaving any residue whatever, and you
have one Of the most accurate methods Of
ascertaining the composition of tho
air. Applying this generally to the
most varying circumstances, it is found
that the air, for instance, on Mont
Blanc, and in the deepest mine, and
wherever else it has been investigated
in any part Of the globe, has the same COM
position. There il nowhere any difference
whatever. The very same regularity is ob
served in the composition of sea water,
wherever you analyze it, except in the i'm.
mediate neighbOrhood Of mouths of rivera
it contains the same amount of salt, and
this regularity of composition is one of the
great safeguards for the existence and pres
ervatiOn of animal and vegetable life. OF
course there are impurities in the air.
. quantity of csrbOnio acid, and in
other places there is found q quantity
of ammonia, and that increases during
the winter time, when no vegetation is GO
ing on, and deere asses in the summer time
These email additions of gases not being
oxygen or nitrogen, are 30 imperceptible
that it requires very large volumes merely
to show their presence, and still larger ones
in order to determine their quantity.
presence of these light impurities il actu-
ally beyond the limits OF accuracy which
Are imposed upon rs by our methods Of re-
search. We can not regulate the pressure
Dr. the temperature - We should like, 90
that there should be no difference
between the pressure inside or ont. There
sre these slight Irregularities which We
llWsys have to allow for, but they
Are still greater than those produced by
The admixture of carbonic. acid and am
monia. And here again you find . wonder.
Ful provision of nature, that the diffueiOn |
If gases 10 90 great that they can NOT, for
my length Of time, collect in inclosed
,laces, except they are specially made i'm
,erviOus to gases. In open nature, in
'oons, In csverns, houees, valleys, on noun
ans, the gases get diffused 20 quickly that |
Vou may stsnd before . limekiln and You |
will hardly perceive it; in fact, in order to
perceive the presence of gas, which goes |
lwsy in volumes. you must actually 60
lose to tho fire and hang your head over it. |