Evening star., 1921-09-25
PERIL EMPHASIZED
In N WRECK OF R2
NJ = -, :. :.
Substitution Of HeIium for
Hydrogen, Reducing Fire
Hazard, Strongly Urged.

a.
The wrecking of the United States
Navy dirigible. the ZR-2. over Hull,
England, with it's heavy loss of life.
emphasizes anew the danger in the
use of an infiammable gas like hydro
gen in balloons and the advantages
in substituting the harmless helium
when the supply makes its use prac-
ticable. according to bulletin issued
by the National Geographic Society.
Quoting from communication to
the society by the late G. Sherburne
Rogers, the bulletin says:
THE qualities of helium that make
1t SO valuable for use in balloons are
it's lightness and it's incombustibility.
Helium is the lightest of the so-called
inert gases. which do not combine
with oxygen or any other substance
and therefore cannot explode or burn.
Dangers Enumerated.
Hydrogen. the gas commonly used
in filling balloons, is. on the other
hand. highly infiammable. Many
great balloon, or rigid airship. cost
ing hundreds of thousands of dollars
TO construct, has been destroyed by
fire in few minutes-some by light
ming. some by sparks from the motor,
and others by any one of. the numer-
Gus accidents that may happen even
when the craft is in its hangar.
"In military balloons or airships the
fire hazard is, of course, greatly in
creased, a single well placed incen-
diary bullet being sufficient to trans
= mass of flames; and in this event
rhe fate of the crew is practically
sealed. This weakness, inherent in
>all hydrogen-filled balloons. was not
only a potent factor in the practical
failure of the German Zeppelin pro-
gram, but has always been draw
back to the development of the
lighter -than-air craft.
with the fire hazard completely
eliminated by the use of helium. how
ever. the risks of ballooning are
greatly decreased and many new pos
'sibilities open up. The power plant
of the airShip may be placed as close
as desired to the great gas bag with
out fear of sparks. and by thus max
ing the design more compact. and so
reducing the wind resistance. the
speed and cruising radius of the craft
may be materially increased.
Sparks Harmless With Helium.
I'm military airships machine guns
may be mounted directly on the en-
NSAopC ihStcdt VI bcils luChtu away
in the gondolas. as far as possible
from the dangerous gas: and, on the
other hand, all danger of attack with
1ncendiary bullets disappears. This
Is not simply theory; tests have been
conducted on model balloons filled
with helium, and all efforts to :ex-
plode them or bring them down with
lncendiary bullets failed.
There is always a chance in
thousand that an anti-aircraft shell
might explode directly within the en-
velope and it might also be possible
to bring down helium-flled balloon
>by driving an airplane through It
bodily. :
The only apparent disadvantage of
felium Is the fact that it Is about
twice as heavy as hydrogen. 100 cubic
feet OF heliunE weighing us ounces
and the same volume of hydrogen
only 8 ounces. Both gases. however.
are so exceedingly light in comparison
+, with air (Which weighs s pounds. per
= 100 cubic feet) that this is of little:
practical importance, the buoyancy
or lifting power of helium being SO
per cent than. of hydrogen. More
over, this gfEater weight has it's
compensation. fo-. hydrogen is 10
light that it passes through the walls
of the gas bag and escapes. at a far
more rapid rate than helium''
HeIium Discovered ON the sun.
bulletin points out, helium was dis
covered on the sun in 1865. It was
, not until 1895. however, that it was
. known to exist on the earth. and it
was then believed to be a very rare
element. 1t was when helium was
discovered in 1903 to constitute be-
veep l and 2 per cent of the mil
-ons of cubic feet of natural gas
going to waste in Kansas, that its
use for initiating balloons first be-
'anle possibility: but no one seems
TO have thought OF such a use for
The newly found gas until. after the
beginning of the world war.
Before the war the worlds total
supply of helium was probably less
Jhan 100 cubic feet. and its value was
enents conducted by the United States
during the war showed that the ele-
ment could be recovered from ma
/ tural gas at a cost of less than 10
cents a cubic foot.
L. S. Has World supply.
Since the armistice huge plant for
tsolating helium has been constructed
ct Fort Worth, where the supply of
natural gas for both Fort Worth and
Dallas is used as raw material. The
plant is turning. out 10000 to $4,000
cubic feet of helium daily, and will
reach soon its maximum output of
5000 to 10000 cubic feet, at which
'iiAC ~ IS cAptCtcu tldI lHc COSI Will
have been reduced to about 10 cents.
The use of helium gas requires bal
looms Of somewhat different design.
since even at 10 cents a foot the gas
is too valuable to be waived" or al
lowed to escape to regulate buoy
:.ncy. Work is being carried on by
riie Army and Navy to develop a type
Of balloon fitted for the economical
use of helium.
At present all helium produced by
The government in it's unique plant
Is stored compressed in steel cylin-
slers. Cylinders on hand can take
care of 1S.000.00O cubic feet. The
hundreds of thousands of cubic feet
of helium which the Army and Navy
now have "filed away" in their metal
containers constitute practically the
world supply.