The citizen. (Frederick City, Md.) 1895-1923, 1900-05-11
LIQUID AIR.
Experiments in Cartridges So Far Un.
satisfactory.

satisfactory.
Ever since it was demonstrated that
liquid air could be readily produced
on commercial scale it has been
hoped and expected that one of the
principal uses to which it would be
applied would be that of an explosive
material for blasting purposes particu-
larly in mines, where the new explo-
sive would have the important advan-
tages of safety in handling and of not
vitiating the air, like gunpowder or
dynamite, by the gases of ignition.
Some months ago a report an
nounced that liquid air had been
formally adopted for blasting pur
poses in the government coal mines
in Germany, says Consul General Ma
son, of Berlin, in !. report TO the State
Department but inquiry proved that
this announcement was at least pre-
mature.
Among the most systematic and in.
teresting practical experiments this
far made in this direction has been
the series of tests lately undertaken
by the Vienna Crystal Palace Ice
Company in the presence of experts
from the Austrian technical committee
, for the War Department The liquid
air used in these tests was obtained
from the Linde Company at Munich,
and shipped to Vienna in open TASKS,
provided with the Dewar vacuum jac-
ket and packed with felt and cotton
Wrappings In wooden cases, with a
loose cap of felt over the open mouth
of each flask.
When put up at the laboratory for
shipment the liquid contained rs per
cent oxygen and 25 per cent. nitro
gen; but before it had reached Vienna
and was used in the experiments it
had lost about half it's bulk by evapor-
alton, and what remained contained
IS per cent oxygen to Is per cent.
nitrogen. The absorbents used in pre-
pairing the cartridges were silicious
mari (Kieselguhr) and solar OIL" and,
according to the report, two methods
of preparation were employed. BY
one process the mari and oil was
mixed in wooden vessel, and the
liquid air gradually added until a stiff
paste was formed, which was packed
In paper cartridge shells covered with
asbestos.
By the other plan, the mixture of
mari and oil was put into the cart.
ridge, which was enclosed in a lead
case with layer of felt between.
and the liquid air then poured in until
the paste was completely saturated.
The cartridges prepared by both meth
DDS were safe and readily transporta.
Bile, and their explosive power tested
by firing at the bottom of deep holes
bored in rock. The results showed
that while liquid air is an efficient ex-
plosive, 1t Is far less effective than
dynamite, guncotton, explosive gela.
tine, or giant powder.
The conclusions of the military ex-
perts were concisely as follows Both
methods of preparing the cartridges
were pronounced wasteful, and in con-
sequence of the rapid evaporation of
the liquid air they must be used i'm
mediately after being prepared; be-
yond fifteen minutes the evaporation
will so affect the cartridge that 1t is
likely to miss fire and it's strength
cannot be even roughly guaranteed. On
the other hand, the cartridges when
freshly prepared are powerful and
well adapted to coal and other mining.
The net conclusion to be derived
from these and preceding experiments
in Europe is that, notwithstanding the
obvious advantages of liquid air as an
explosive for mining purposes, the
rapid deterioration of the cartridges
and their varying and uncertain
strength are obstacles so serious that,
until they can be overcome, its value
and application to that use will re.
main experimental and comparatively
limited.