The sun. [volume] (New York [N.Y.]) 1833-1916, 1907-07-07
WELLMAN'S POLAR AIRSHP
HOW THE AMERICA rs EXPECTED
TO DO ITS DUTY.
The Explorers Hopes n 60 Figures.
which Are Said Not % Lie-Tho ship II
Immense-Carries Many Clever Devices.
Including o sausage Guide Rope.

aNh&hy AHCNOt SONtCtus
Including = sausage Guide Rope.
II Walter Wellman's airship does not
fly to the pole on the wings of the Arctic
breezes IL will not be beoause Mr.. Wellman
has JAILED In his attention to long and short
division, decimals and the like.
The article he contributes to the June
McCture's Va like a mixture OF Jules
Verne, fractions n advanced chemistry.
II there we're u a thing IA a mathe-
NAUTICAL certainty 1t would seem TO have been
corralled by Mr.. Wellman.
Blu there 10 a tradition that only one
thing is absolutely certain to happen and
that 10 the unexpected. Lots of pe.p.5
will ave up the Mcclure article and Lcep
tab to see how all these wonderful calcu-
lations work out.
The America, as Mr.. Wellman patri-
otically calls his airship. is 1888 feet long.
Its greatest diameter is 52.5 feet.
The steel car underneath it is ii5 feet
long, and from the bottom of this car to
the top Of the gas reservoir the distance
is 65 feet. the height Of a four story house.
The surface Of the gas reservoir or balloon
Is $4,000 square feet, or more than half an
acre, and the weight Of the envelop Of cot
JOu, sllk anu TuDDer - TWO TONS.
when tho ship sets out on its voyage"
says Mr., Wellman, there will be % $40
pounds Of men and materials moving north
ward in this engine Of the air"
At this point the explorer gets busy with
his deoimals and division. At S~pitzbergen.
where the airship has been building. they
expect--the word expect occurs fire.
Quently-to make hydrogen gas 80 per cent.
pure, with a lifting power to the cubic foot
Of .o7see2 pounds. With a capacity in the
bag Of PCS. 400 cubic feet they expect to lift
10. $50 pounds.
Ordinary spherical ballons.' says Mr..
Wellnan. like the one used by Andree.
are usually Of a single thickness Of silk or
cotton several times vanished.
W have used three c~ottons, zach rub
bered. or two cottons and one silk, all rub
bered. in h central part OF the reservoir.
where there Is the greatest pressure Of gas.
and two cottons in the ends.
These fabrics are stuck together In one
piece of cloth. and though the thickest
weighs only a little more than one-tenth
OF a pound a square foot, the tensile
strength runs to 500 pounds to the foot, OF
five times the maximum work put upon the
fabric by the pressure of the gas. This
factor OF safety is carried throughout.
In addition to the tensile strength OF the
cloth every seam is Tapped about one inch
M doubly sewn. Inasmuch as there is
danger Of the gas escaping through the
needle holes, all the sewing line are covered
by double bands Of silk cemented TO the en-
velope-frst a band covering the seam.
then over that another and wider one.
The primary purpose OF these bands 10
to make the envelopea as gastight as possible.
but incidentally they add enormously
to the strength OF the skin. The outer sur
face OF the balloon 10 c~aoutohouc. vulcan
lied, quite smooth, well calculated TO shed
rain and snow and to prevent moisture
entering the fabric. There 10 no netting
Of cordage or wires on the outside OF the bal
loon to hold snow, frost or rain water"
Mr.. Wellman next takes up the question
Of loss Of gan by leakage. He allows for
l.5 per cent. daily, though expecting
much less. This would diminish the lifting
power at the rate Of IL pounds an hour.
The loss il offset by the rate at which the
gasolene tank will be lightened.
In the cargo are $500 pounds Of gaso-
Iene. Every hour the motor is in oper-
alton il consumes a pounds OF this.
~ ~ ASb VI thaby Bctooito
Can you make more gas on the wayp"
Cant you carry a supply OF gas with
you. compressed in steel tanks?" MIR.
Wellman replies: Instead OF needing
new supplies Of gas en- route. we shall
have gas to burn. And we propose to
burn it-that is TO say. burn the surplus.
be IL much or little. The more we work
the motor the more rapidly we reduce
A.. uu.tulN - A.. Ia.l 1Ax.l - A.
more the load is reduced the more gas
we have to dispose Of.
Ordinarily this surplus gas is released
deliberately. through the valves into the
surrounding air. But when we remem-
bered the high c~alorific value Of hydrogen,
that it's heating power q pound Ia more
than three times that Of gasolene. we said:
A pity TO waste so much energy. to throw
il away when it lies within ten feet OF our
motor. Can't we burn 1t as fuel?'
in response to this Chief Engineer
Vaniman rugged a motor with a two way
valve. Through one inlet came gasolene,
through the other hydrogen. To exper-
iment he started the motor with the liquid
fuel. then shut of the gasolene and turned
ON the gas. Instantly the motor accel-
Grated it's rate. This change from fluid
to gas. and from gas back TO fluid. was
effected by the mere turn of a valve. The
system worked perfectly.
without working the calculation too
fine, for every ten hours of full motoring
with liquid fuel we gain two hours Of mo-
toring with the gaseous fuel. which is re-
lieved Of its load as a buoyant force. Hence
the store of fuel carried in our ship, roughly,
ia as follows: Hours Of motoring with
gasolene, $50; with hydrogen, 80; total,
1870 hours.
The most unfsvorable aspect Of the
polar area. 80 far as meteorological condi-
tons are concerned. is the high humidity,
the prevalence Of fogs and the precipita-
ton Of snow or rain. We have to lake
into account the probability that almost
any hour the huge surface of our gas reser-
voir may take on several hundred pounds
weight of nov or moisture, and the pos
sibility that In a snow or sleet storm Of
unusual severity 1t may take On as much
as a thousand pounds. At all hazards,
we must prevent the America being over
loaded in this manner and forced down