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TOILERS UNDER THE SEA
British Admiralty insisted upon better
workmanship and more reliable performance
on the part of the pumping equipment,
but the English authorities still
held to the hand-driven apparatus. Investigators
in the United States Navy,
however, did much better than this.
They made a long stride forward by introducing
another link in the safety chain
devised for the security of the Government
divers. Now, instead of using hand
pumps they use steam or electric-driven
air compressors, and these store the air
in suitable tanks at high pressure.
As a result, our naval divers, instead
of drawing their air directly from pumps,
have their supply hose connected to the
reservoirs that hold enough of this vital
element in reserve to meet all needs for a
long time after the compressors are
stopped. This removes the hazard of inattention
on the part of surface attendants
and dependence upon the continual
operating of either hand-worked pumps
or compressors. More than this, the
diver is emboldened, and he sinks
to the far-away sea bed in confi-
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from the helmet, after it has come down
tii the diver for breathing purposes, goes
directly out into the enveloping water—
unless the dress be of the self-contained
sort in which the exhaled air is drawn
through a cartridge of caustic soda so as
to save the unused oxygen for re-inhalation.
The air escaping into the sea commonly
makes a good deal of noise in the
helmet. This is a disadvantage, because
it interferes with the best use of the
submarine telephone which is recognized
now of such practical importance. Our
naval divers have their helmets equipped
with an improved regulating escape
valve, and this is so constructed that it
greatly lessens these objectionable noises,
and telephonic communication is therefore
made more nearly perfect.
Today, divers can drop to the sea bed
almost with the speed of falling stones
without fear of being crushed to death
by the rapidly-increasing pressure of surrounding
water. They can do this because
the air supply, when
drawn from tanks highly
charged, is so abundant
HIS SUIT A RECOMPRESSION CHAMBER IN ITSELF
"A" is the compressed air tank. "B" and "D" are parts of the chemical apparatus for cleansing exhaled air for further
use, and "C" is the telephone connection. By means of the net of cloth-covered chain the suit is made to serve as a
recompression chamber.
deuce, knowing that if he takes proper
care his air supply will not fail him.
An abundance of air is fundamentally
the secret of successful and safe deep
submergences.
In most diving suits, the air escaping
and continuous that it offsets at every
foot of submergence the growing hydrostatic
pressure. This means that the
underwater worker can reach the point
where he wishes to operate with the least
exhaustion in getting there. But nature