The record-union., 1897-10-17

grees below the atmosphere at go de-
grees Fair Inasmuch as it boils rap
idly on the surface, owing to its OBJ
! sorption of heat from the atmosphere,
1t looks like carbonated milk on the
surface, but upon dipping some of 1t
out in a glass and observing It's color
| through the glass, it has very much
| the appearance of ordinary water, and
about the same weight. Its tempera-
] ture is very deceptive, for as It runs
! from the condenser one may allow IL
| to trickle over the fingers for snort
space of time, and it appears TO nave
1 the atmospheric temperature me
| truth, however, of the matter is tnat
| it does not come in contact with the
| fingers at all; the hand being some
| thing like 4S0 degrees warmer than
| the liquid, it throws the liquid INTO
| spheroidal state and 1nterpoSeS De-
| tween it and the finger film OF atmos-
| pheric air The sensation is very mucn
| like pushing ones hand into a bag
of feathers or into a mercury patn, al
| lowing of course, for the difference IN
| weight between the mercury and the
liquid air. If, however, the hand is
immersed in the liquid sufficient time
to establish contact, the flesh would
be burned, the same as II 1t were ex-
posed to 40 degrees of heat, measured
above the atmospheric temperature. Ii
test tube of one and one-half inches
diameter, having a couple OF POUNDS
| of mercury in the bottom is immersed
in liauid air. the mercury will be frozen
solid in a few seconds, and may be
hammered out and otherwise manipu-
lated the same as lead An alcohol
thermometer of large size will be frozen
instantly upon being immersed In the
liquid.
! A tablespoon of liquid air poured on
about a fluid ounce of whisky VIII
freeze it at once into flat scales, giving
the whole the appearance and color OF
cyanide of potassium. This may be
emptied out on a table and will re-
main frozen in that condition for fully
five minutes. One thing that impresses
one is that while all molecular motion
is practically arrested at this tempefa-
ture, the odor is perfectly distinct
! showing that these particles Whlch
| stimulate the sense of smell are active
| and Independent of the temperature.
/ A handkerchief of either silk, linen or
| cotton saturated with the liquid, VIII
be charred and destroyed just the same
as if it were put in an oven and brown
| ed. though no change of color IS ap-
parent. It's evaporation is quite slow
| and it may be carried about for num-
| ber of hours in an open vessel without
entirely disappearing. 1t probably rep
resents a compression of about TOO at
mospheres, and would, therefore, in
confined space and at 60 degrees tenn
perature, represent a pressure of some
where from ten to twelve thousand
pounds to the square inch.
| Liquefying air is not new thing; 1t
has been performed by exerting enor-
nous pressure or by freezing air to an
unusual degree, or by a combination of
pressure with refrigeration. There are
so many uses to which liquefed air
can be put that scientists hardly know
where it's usefulness will end If 1t can
be produced at low rate of cost in
commercial quantities. Among other
advantages, air in the portable, cheap
form of a liquid, as 1t passes back to its
ordinary state can be used for illu-
minating purposes by mixing its es-
Gaping gases with atmospheric air in
certain definite proportions Moreover,
as driving force in the way of de-
tonators, or explosive material to drive
engines, liquid air is obviously power
that can be, under certain conditions,
profitably applied.
Fluid air costs about 10 marks ($2 2o)
for five cubic meters reduced. This new
method is the invention of Professor
Linde of Munich. 1t produces the
LIQUID for 10 pfennings (21 cents) for
five cubic meters, and it yields the pro-
duct either as a gas or fluid, as one
wishes This is one of the most in
| genious pieces of mechanism recently
| known; its chief feature is its economy
of working, for it uses air to refriger-
ate air. After the pump has worked
for a certain time, one turns ahcock
and the LIQUID air runs out at tenn
perature of 273 degrees below zero. In
! Professor Linde's method, an air pump
of five horse power condenses air to a
pressure of 200 atmospheres; this air
passes down a spiral tube and is let out
| in chamber, causing great cold; then
it rises and passes on the outside of
! the spiral tube, bathing it and thus
cooling the new air that has been
pumped into the tube to take tssplace
/ This cooled air follows on into the
| chamber. expands and again lowers its
temperature, then passes on up around
the spiral tube; but as its temperature
| has become much lower, the new air
lin the tube is still further refrigerated.
This circulating process goes on, until
the new air pumped into the tube
reaches the expansion chamber at a
temperature of 273 degrees below zero,
when it drops into the chamber in
the form of liquid. Thus the air, stead
fly cooled, is made to refrigerate the
newly pumped air more and more un-
til the necessary degree of cold is at
tanned Another idea, which may or
may not be an Improvement, is to have
the pump and all parts of the machine
kept very low in temperature
pressed Air.
The Severed Bond.
They stood beside little grave,