The daily morning journal and courier. [volume] (New Haven, Conn.) 1894-1907, 1898-05-09

tie way into the water, boiling all the
while. Then it will rise again, sink
once more little lower, and so contin-
uing will perhaps finally reach the bot
tom of the jar before it all boils away.
In the state in which the liquid air is
| poured on the water the experiment
| proves that it is just a little lighter
| than the water. In that condition 1t
contains about one-fourth oxygen and
| three-fourths nitrogen. The nitrogen
is more volatile than the oxygen and
lighter. This boils off faster than the
oxygen and SO leaves the liquid heavier
than it was, and it begins to sink.
| Finally, when little is left but the OK
ygen, it sinks to the bottom.
This liquid air is curious stuff. 1t
cannot be handled in vessels of iron,
steel, glass or rubber, for it makes all
of these substances so brittle, by it's
| intense cold, that they would snap to
pieces at the slightest provocation.
One of the experiments shown is to
take an ordinary tin cup and cool it for
a moment by holding 1t in the liquid
air. When it is withdrawn it an be
| broken into bits with the fingers just
as If it were a wafer. AS the metal
gets warm again it resumes it's ordina-
ry toughness. You can touch the IL
quid air. If you do it with caution and
skill, and not get hurt, although it's in
tense cold would destroy your flesh as
quickly as a red-hot iron AS you
draw your fingers through the liquid
air it feels cold. but not intensely so.
This is beause it does not come actual
| ly in contact with the skin. The heat
from the fingers sets it to boiling and
there is a layer of free air always in
terposed between the liquid and the
fingers. When a woman started to
touch the liquid air with gloved fingers
she was stopped and warned that a
moments immersion under such cir
substances would burn her hand as If
she had put it into furnace. If you
let drops of the air fall upon your hand
they do not do any injury, but bound
off in the same fashion that water
drops hop about on a red-hot stove.
Your hand is really red hot as COM
pared with the drops of liquid air.
The liquid air is handled in cans Of
copper or aluminium. To keep it the
cans are covered and lined with felt
and light covering Of thick felt is
placed over the mouths of the cans.
This covering must be left loose, for If
it were not the evaporating air would
gather within the can until it would
rend in two anything much less strong
than a steel cannon. 1t is this con-
slant evaporation which keeps the air
in it's liquid form. 1t takes in heat so
slowly that a gallon can of air has
been used for experiments during a
whole evening and lasted for four or
five hours. With can of this cold Ii
quid at hand one can freeze any of the
things which we are accustomed to see
in liquid form.
This great cold has very curious
effect upon water or anything which
contains much water. A little water
poured into the can of liquid air is
frozen instantly and then, if allowed
to remain until it is at the tempera-
ture of the liquid air, 1t will be found
to have become so brittle that the ap-
parently solid cake of ice can be
crushed and crumbled to fine powder
!, in the fingers. A beefsteak frozen in
, this manner may be broken UP in the
} same way, although before it was froz-
: en- it may have been tough enough for
theoretical boarding house purposes
, A light rubber tennis ball immersed
) for moment in he liquid air an6
| then thrown against the wall broke
, into bits exactly as If it We're thir
glass.
Mercury forms the base for a num-
Der of interesting experiments. Pro
lessor Barker of Philadelphia, who has
J been showing liquid air in a number o.
: lectures, takes about two pounds O
this mobile metal and pours it into {
hammer shaped wooden mould, at the
same time standing an ordinary wood
en- hammer handle in it in the mould
: Then he pours liquid air over the mer
t curry few times and eventually take:
out the mercury, frozen solid abou
the handle, and drives nails with it a!
t IL it were hammer of iron. Mr.. Trip
: Ter pours mercury into a trough abou
eight inches long and places in eacl
end of the trough some iron hooks
He freezes the mercury, removes +
from the trough, and hanging it up b,
one of the hooks, suspends a fifty
! pound weight from the other hook. II,
leaves it hanging while he does othe
experiments, and it will be twent.
minutes or more before the mercur.
/, gets warm enough to snap in two ant
: let the flfty-pound weight drop.
An interesting experiment was on
in which the air of the room was actu
i ally frozen before the eyes of tn
: spectators. This was done by taking
Y some of the liquid air in a glass tub
and connecting this tube to an al
$ pump. AS the ordinary air pressur
I was removed the liquid air boiled wit
great fury and this so reduced tn
temperature of that remaining in tn
:, tube that the wathers saw the air o
: the room gather in liquid drops on tn
outside of the tube and finally trickl
down it's sides and fall off. Durin
one of these experiments, when a con
;, siderable quantity of the liquid air ha
been spilled, a lot Of it ran over tn
handsome evening gown of one Of tn
women in the party. 1t wet the fabri
i like water and dark spots appeared a
1 once. 1t was easy to see that the wo
! man was worried about her gown, an
t although she did not move at once, sh
i was seen examining 1t carefully littl