Evening star. [volume] (Washington, D.C.) 1854-1972, 1931-06-14
NAVY TO TEST BELL
ABLE TO SAVE IS
New Device Will Be Tried Out
on Fatal S-4 at Early
Date.
Continued From Page one.)

Continued From Page One)
substitute for the lung" which will re-
main the primary escape continuance
for American submarines. 1t will be
used in emergencies where use of the
lung is impracticable. Such contin-
gencieS are when the water is too cold
for safe escape by means of the lung"
or when members of the crew of the
disabled vessel are too weak from gas
poisoning or injuries to help themselves.
The new rescue chamber, it is
thought, might have effected the re-
lease of the men trapped in the ILL
fated British submarine PoSeidon, sunk
recently in the China Sea. Had 1t
been in existence at the time of the
S-4 disaster, too, serious loss of life
probably would have been averted.
AS in the case of the lung" which
was the invention of American naval
experts, the Government will make no
attempt to keep the design of the new
apparatus secret. Under this policy
the rescue chamber undoubtedly will
be made available to other navies.
Tests at 100 Feet.
In the tests with the S-4 at New
London the chamber will be tried out
at depths Of 100 feet or more, with
conditions Stimulating those of an actual
disaster. The deep sea experiments
will follow Immediately after several
preliminary tests to begin June % at
the New York navy yard.
Experiments with three previous
types of bells were conducted at Key
West during the Winter of 1890, with
varying degrees of success. AS a result
Of those tests the three types were
abandoned in favor of the new design,
which has been developed in the bureau
of construction and repair of the Navy
Department under direct supervision of
Lieut. Comdr. Allen r. Mccain.
Because of McCann's intensive work
in designing it, the rescue chamber has
been referred to as the Mccain bell, !"
but Mccain modestly declines to &C
cept credit for its invention. He de-
clareS 1t is "a bureau development" to
which a number of persons have con-
tributed valuable ideas and advice.
Technical details of construction were
handled by Lieut. Comdr. j. w. Page
of the Naval Construction Corps.
Pear Shaped Chamber.
The bell as now evolved is a large,
pear-Shaped chamber of steel, with
self-contained air motors for drawing
1t to the deck of submarine by means
of steel cable, previously hooked to
an eye on the hatch of the Sunken
craft by 81 diver. It is operated by a
crew of two men, who stay in an air.
tight upper compartment. The crew
is supplied air, light and telephone
services through cables from a tender.
The narrow, lower half of the bell
is open to the sea. When the bell is
drawn flush against the deck and
around the hatch of the submarine, a
rubber gaSket presses tightly against a
circular steel plate around the hatch
and completes a seal. The water in the
lower part of the chamber then is eX-
PEELED, making of the chamber a huge
vacuum cup" which is held rigidly to
outside. In case the submarine is list
ing badly the bell may be clamped
down with bolts
With the lower compartment empty
OF water it is possible then for those in
the upper section to open a water-tight
hatch. descend to the deck of the sub
marine, open the hatch of the vessel
and allow the submarine crew to enter
the bell. The numerical limit of those
rescued at each trip is governed only by
the space limitations of the upper
chamber. 1t is estimated about 20 men,
including the crew of the bell, can crowd
into this chamber if necessary.
Ascent Is Regulated.
With the rescued men safe in the up
per compartment the operators of the
bell have only to replace the submarine
hatch cover. ref1ood the lower compart-
ment by the turn of lever, and the
buoyancy of the bell causes it to break
away and rise to the surface. The speed
of ascent may be retarded by "brak-
ing clutch" connected with the cable
hooked to the submarine.
Water ballast equal to the weight of
each man taken aboard the bell is
emptied before the ascent, to compen-
safe for the added weight. The ballast
is carried in large cans, each contain
ing 30 pounds of water, and is dis
charged by the simple process of dump
ing the contents of the cans into the
lower chamber before the latter is sealed
of and refllled with water.
On reaching the surface the chamber
is hauled partly out of the water by
a crane, small hatch on top is opened
and the rescued men are taken aboard
the tender. The bell then may return
Immediately for another load of pas
SengerS.
Throughout its Journeys to the bot
tom and back the men in the bell are
in constant telephone communication