The bystander. [volume] (Des Moines, Iowa) 1916-1922, 1916-07-21
May YET RAISE
SUNkEN TREASURE
Work Of Navy Divers Shows What
Can Be Done at Great
e 91s l,5G
Depths.
MAKES SALVAGE POSSIBLE
Projects for Raising lon0-lost Rich
GaIleys and Warships Now More
FavorabIy considered Than
Ever Before.

Neutrality-suspicious. I'LL TIE IuuAOuS
Of dollars that now lie at the bottom
of the sea in the form of ships and
their sunken treasure be forever lost
to the world? Most Of the vessels that
have been sunk, whether by accident
or In the course Of war. lie in compare.
lively shallow waters. many Of them
at q depth of less than 800 feet, and
the problem Of their recovery does not
seem entirely hopeless in the light
Of recent improvements in deep-sea
diving and the feats accomplished by
the expert divers Of the United States
navy. The matter is the subject of an
article In the bulletin Of the Pan-Amer-
lean Union at Washington. In discuss
ing the organization Of companies in
the United States whose purpose is the
recovery of some Of the wealth. now
lying in the oceans depth. the writer
Of this bulletin says:
Certain it is that the project Of
recovering sunken ships or the most
valuable Of the treasures that have
gone down with them is more feast
BILE now than it was only four or five
years ago. Such great improvements
in diving apparatus have recently been
made that 1t is now possible for
diver to operate for limited time even
at the great depth Of 300 feet below
the surface. These improvements are
largely due to the remarkable expert
ments in deep-sea diving conducted un-
der the auspices of the Bureau Of Con-
struction and Repair of the Navy De-
partment of the United States in 1914.
Prior to that time the greatest depth
reached by divers was 21O feet, two
English officers having accomplished
that feat during a series of tests car
ried on by the British admiralty in
1907. For the benefit of those who do
not appreciate the difficulty of diving
to such depths + may be stated that
at a depth of ten feet below the sur
face the pressure is 4.33 pounds per
square inch Of surface of the body SUBJ
merged. This pressure increases pro-
protionatsly and at: a depth of 100
feet it has increased to 43.3 pounds
and at a depth of 800 feet to 1899
pounds.
Makes Salvage Possible.
Notwithstanding this tremendous
pressure, the expert divers Of the
United States navy" this bulletin de-
clares, shave succeeded in not only
reaching a depth of 300 to $50 feet,
but in remaining at that depth for
from five to twenty minutes at time,
making examinations and observations
in regard to sunken vessel that
made its subsequent salvage possible.
This work was done in connection with
the raising of the United States SUBJ
marine F-4 which, it Will be remem-
bered, plunged to the bottom Of the sea
just off the harbor Of Honolulu. on
March rs, 1915. Not only did the div
ers establish new worlds record for
deep-sea diving upon that occasion, but
the subsequent raising and recovery Of
the F-4 is the only instance In history
where a sunken vessel was recovered
from depth Of 800 feet"
The bulletin writer thereupon gives
q brief sketch of the history of diving
as a useful art from the time Of
Aristotle down to the present, and af.
ter describing modern diving out
fit and explaining Id some detail the
matter of the divers being subjected
to two pressures, viz, the pressure of
the air inside the helmet and suit and
the external pressure of the water, con-
tinues as follows:
"The necessity Of having the air
pressure within the diving dress COM
pensate the external water pressure,
thus subjecting the diver to pressure
directly proportional to the depth to
which he descends, is the dangerous
element in deep sea diving. At a.
depth, for instance, Of 100 feet, diver
must be subjected to pressure Of
four atmospheres, Or 60 pounds per
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