The mirror., 1917-09-20

gaseous compound carbon and oxygen 1t is procured by
the of combustion and respiration and
in the air, though 10 minute quantity Plants
live and absorb into their tissues; they abstract
assimlate its carbon and its oxygen the atmosphere
condition 1t is also present spring water and
in quantities. that spakles eervesces also produced
during the of putrefacon fermentation and slow
animal and vegetable substances of
largely employed by the manufacturers of bread
aeraed Under of about 800 pounds que
6e and when allowed escape through small jet rapidly
evapoaes and intense cod much become
frozen. 1t does support burning The gas derived
it, carbon doxde, is invisible and heavier than air by
halt and has odor and slightly acid pure
the be espired supports repira-
ton combustion When the portion atmosphere
creased to considerable extent happens sometimes endan-
life. The familiar 'rising of bread brought by
carbonc acid escaping through and permeang dough-
making it light and porous. In this form is known yeast
baking powder. We its also in the chemical
fire engine
In of the world large quantities of carbonc acid
constantly issuing from openings of the eahs surface
Two such places the Poison Valley lava
Groo del Cane. Naples, in Italy. The
valley about half mile around about thirty five deep,
in which the air loaded with carbonc gas animals
entering killed in few minutes Even birds that fly
the valley they do high above
The Groto del Cane, the Groto of the Dog, is small
in the of volcano. carbonc acid
gas flows constantly into the groo but the level of the
does reach the height of mouth. When
air breahed and again. the quantity carbonic
acid in is increased much, that may become deadly
the air in the Poison Valley.
Two other gases that may generally be found
and ammonia The first is merely form of oxygen
produced the passage lightning through After
thunderstorm said be present. sometimes suf
hcien proportion to give the air slightly pungen odor
is active chemically than the ordinary of oxygen
and consequently has stimulating effect upon animals
Ammonia, hartshorn it is sometimes called, from
by
har deer is almost always present in the air in small guam
titles 1t produced chiefly by the decay of animal and vege
table NATTER especially the former Though present the
in small quantities. it is of much value the plant world
because contains nitrogen in form in which be read
lily be absorbed by plants All plants contain nitrogen,
which is essential their growth, but the greater part of the
nitrogen the air in such form that be absorbed
by them They obtain their supply from the soi which
usually contains nitrogen in form that be taken up
by plants, and from the ammonia in the air. The latter is
taken directly the air by the plants but the rains falling
through the air absorb the ammonia and carry the SOIL
from which it is taken into the plants by their roots
Besides the gases that have been mentioned pres
in the air, all times small quantity of waer-vapor,
which is in many ways mankind oxygen
ITSELF The quantity of the always the
AS rule, the quantity greater air than in cod and
less land than Frequently the air feels damp
in cold weather. and dry in hot weather. and is natural
suppose that there vapor in the damp day than
the dry This, however, always There
cold day in winter though the winter day may
moist You will be able understand why this is by
comparing the air to If we fill sponge with water.
and squeeze gently little will be forced of it,
then the pressure the sponge When the air
cool will appear dry the surface but there will still be
it, and being squeezed harder than before will be-
moist the surface and will be forced of
Now cold has effect upon laden very much
like pressure the SPONGE When the air coo of
the moisture forced of it, and the air damp When
it again. the air dry though there is still
vapor in it. 1t dry because it absorb
vapo the dry after squeeze it,
though still contains From this that the air
always moist when there is much water-vapor in
it, dry when there only little 1t feels moist when
there much waervapor present it hold, and dry
when hold than already has, And also
that in hot weather the air hold much moisture
cold weather. that whether the air feels dry
moist is generally much watevapor in it in hot
weather in cold
All plants, from the great redwood of Cali
fon the smallest flowers that dot the fields need cabonc
acid gas keep them alive and make them grow Their
the power when the shines them take
carbonic acid from the air and oxygen exchange
way you balance is kept should be-
oxygen needed by animal of all kinds furnished by the
plants and carbon acid required by plants thrown off
in the breath of animals.
O:-Can you tell me if absolutely
6e-proof3 Can they be destroyed through heats B.A.
A:-Concete latter "seing') not fire.
proof in the that they be destroyed aposed
into gas by using extraordinary heat Sand, limestone.
quartz of which manufactured product easiy
vapozed which easily generates heat up
to $500 degrees-Fahrenheit.
Concrete in its various forms are fre-proof in
the that they withstand destruction by the ordinary
and flames generated within without building our
fire departments are called upon to exnguish.