The morning news. [volume] (Savannah, Ga.) 1887-1900, 1899-03-10

when the hydrogen was boiling away at
one-inch pressure.
In 1923. Faraday. in he laboratory of the
Royal Institution liquefed a gas Chic
rine) for the frs time in the annals of
science. Seventy-ive years afterward
Frof. Dewar working in the same labor
atory, succeeded in reducing to liquid ny
drogen and hehum, the two gases to hold
oui against the onslaughts of modern
chemistry. The apparatus used in the
Royal Institution to-day differs very great
iy from that used by Faraday.
Prof. Dewar's chemical laboratory has
been compared TO the engine room of all
Atlantic liner. and, indeed, IL does not
come up to ones ideas as 10 the workshop
of a chemist. Here are to be found gas
engines huge compressors, pumps. belts,
shafting, and a whole host OF engineering
appliances. For every gas there is a crit
ical temperature. and when the gas is
above the temperature no amount of COM
preston can reduce il to a liquid. The
first slep then is to get the gas down TO
the required temperature When this Is
done it is compressed until IL assumes the
liquid states. Oh May 10 an experiment
was started with hydrogen cooled to 205
degrees centigrade and escaping continu-
ously under a pressure of $50 degrees at
mosphere from the nozzle of the coil OF
pipe at the rate of ten TO fifteen cubic
feet minute in a vacuum vessel, tloubly
silvered. of special construction, surround
ed with a space kept below 200 degrees
centigrade. With these arrangements
liquid hydrogen began to drop from this
vacuum vessel into another, doubly iso-
lated by being inciosed within a third coil,
and in five minutes twenty cubic cent?
meters of liquid were collected. In its
liquid condition hydrogen is clear and col
orless, looking for all the world like wa
ter except that il bofls away al this ex-
ceedingly low tempeTa ture-the lowest that
man has ever reached.
Prof Dewar has shown how liquid hyt
drogen can be used as condensing agent
for the production of very high vacua the
contents of a closed tube containing air
being quickly condensed as solid air when
one end of the tube was immersed ~ the
liquid. When the portion of the tube from
which the air had thus been removed by
condensation was sealed off with blow
pipe, a vacuum so high was obtained that
it would scarcely allow an electrical dis
charge to pass. Sir William Crookes has
stated that the vacuum produced by liquid
hydrogen in so short a space of time as
one minute was higher than he could OBJ
tain with the ordinary pump after work
ing ID for several hours. The first question
usually asked a scientific man when he
makes a discovery is, What is the use of
it?" Liquid air has already been of very
great use to the scientific man in his in
vestigations, and there is no doubt that as
time goes on practical applications for it
win be found.
It has enormous expansive and explosive
power and experiments have been made in
this direction. For instance. when liquid
air, enriched by the evapora lion of a large
part of its nitrogen is mixed with now
dered charcoal an explosive is formed
comparable in power to dynamite, which
can be made to go off violently by using
a detonator. This new explosive has been
used in coal mines for blasting purposes,
and its chief advantage is its cheapness
the cost being to all intents and purposes
simply that of the power used in quifying
the air Then liquid air is being used in the
manufacture of chlorine, and in some other
chemical industries. The fact that at the
temperature of liquid air the tenacity of
metals is enormously Increased suggests
wide field of usefulness for this sub
stance. Steel, which breaks ordinarily with
stress of thirty-four tons per square
inch, is nearly twice as strong after be-
ing immersed in a bath of liquid oxygen
or air. AT these low temperatures metals
are perfect conductors of electricity and
do not dssipate the current at ALL as they
do at ordinary temperatures. Thus, if any
one could devise a commercial method of
keeping copper wires irrrnl in liquid
air, II would be possible to make the Fails
of Niagara provide electricity sufficient to
light every city, drive every train and
tram, and run every mandatory In the
whole of the United States. Liquid air can
now be produced so cheaply that it will
be strange if uses for 1t are not quickly
found.