The New York herald., 1922-02-22

the German Zeppelins that harried Lon
don time after time during the world
war. The ZR-1 Is under construction by
the navy, however, and recently ar
rangements were made, with the CO.
operation of the allied Governments. that
the Zeppelin plant in Germany should
build for the navy a Zeppelin of the l.
type, which proved successful during the
war.
The ZR-1 was described to-day as
strictly a reproduction of the best Ger
man airships, only slight notifications
in plan having been made by the Navy
Department. The policy of the de-
partment in planning the ship is under
stood to have been to attempt no inn
provement until the tried and proven
practice Of the German airship builders
had been duplicat ted successfully and
then to advance in speed and size by
slow strides and with emphasis laid in
every succeeding design on safety and
sound structural developments.
The Zeppelin to be procured in Ger
many also will be of the proved type and
the business of airship building in the
country on a major scale, either for
military or commercial purposes, has
been generally expected by technical
officers to start from this point. In this
connection, IL was said to-day that ex-
animation of all German records had
failed to reveal any disaster such as
that to the ZR-2. which was far larger
than any German built craft of the
kind, or to the Roma.
Whatever may have been the cause
of the wreck either of the ZR-2 or the
Roma, ii is certain that the flying Off
GERS of the army and navy do not re-
gard these tragic accidents as offering
any reasonable ground for the abandon
ment OF the attempt to produce for the
American military services ships of the
size and kind, particularly for employ
ment in coast defense operations.
In the investigation particular atten-
tion will be paid not only to the possi-
BILE structural defects of the Roma and
the information reaching Washington
that the box elevating plane would not
work. but also TO the question whether
the ignition of the gas in the Roma
was caused by contact with the high
tension wires. There are some aero
nautiacl experts in Washington who de-
clare that the ignition OF hydrogen ball
loon gas by high tension electric wires
has never before been the cause OF an
airship disaster. The statement was
made tonight that when the Roma
had its first trial trip propeller caused
a large cash in its gas bag near one OF
the engines, but that this did not result
in disaster.
The great advantage OF nelium gas
over hydrogen is that helium is non-ex-
plosive while hydrogen Is highly ex-
plosive In a hclium filled airship there
Is no danger OF explosions due t. static
or electric connections. or from ignition
due to sparks from exhausts of motors
Probably the greatest disadvantage in
the use of helium Is its cost OF produce
tion. its availability and Its buoyancy
es compared to that OF hydrogen. Hy-
drogen, with 100 per cent. purity and
under standard atmospheric conditions.
has a buoyancy OF 10 pounds per 1000
cubic feet OF air displaced, while helium
under similar conditions has 644 pounds
lift. When helium has lost purity and
consequently lift on account OF diffusion
with air, 1t can be put through re-
publication process and used again.
The navy maintains a helium plant at
Fort Worth, Tex. where helium Is ex-
tracted from natural gas by compressor
systems II is required that a plant of
this character be located where there is
an abundance OF gas and also an abun-
dance OF water for cooling the numerous
compressors
Tho natural gas after passing through
this plant becomes purer Illuminating
gas than before, when II is then re-
turned TO the gas company for CONNER
clal use. The natural gas Is first passed
through lime. which removes carbon d.
oxide II Is then liquefod, leaving nitro
gen and helium gases. which are drawn
off and further compressed. thereby IL
quefying the nitrogen and leaving the
helium. which Is drawn off and COM
pressed into cylinders and placed In
storage for shipment.