The sun. [volume] (New York [N.Y.]) 1916-1920, 1919-08-03
xxEk--

closer and closer to the horizon Ma,
time slipped by in getting her trims
for her dip and during the whole n.
Rod she drifted away from the desir.
spot. Herein lay the germ O; a ne,l
catastrophe.
The type Of submarine in aues,io
carried her fuel tanks outside OF Ma
main or pressure resisting hull. Wb.,
full these tanks were safe against N
crushing force of the sea, but the en-
gines had partly exhausted them an
this fact was not needed. Accordingh
they gave the vessel added buoyancr
and to just that extent more waits
had to be taken into the ballast tanh
to make the boat submergible. Nov
see what happened when she sank b.
meath the surface. Before she vr
200 feet down-her officers and Grew
were inside of her-those fuel tank
collapsed and the air escaped frcn
them. The result was exactly EQUIV.
alent to suddenly increasing the crafts
dead weight either by leakage or added
water ballast. Without warning she
hastened oottomward, but she did no,
halt where 1t was expected she would +
The submarine had drifted over hOL
256 feet deep, not 200 feet, and no one
realized 1t until she came to stand.
still with the hand of her depth gaug
quivering It's startling messagel
Fails to Rise.
At once the usual tanks were blOsn
free OF water but the boat did not RE
because that discharge was not suH.
cient to overcome the UNEXPECTEDLY
increased negative" buoyancy. Imas
inc how those men felt. No wonder
their cheeks blanched and for a while
there was excitement and confusiOn
True, the boat was not leaking, but
neither was she responding as she
should have done: she seemed to b
glued to the waterbed.
Finally emergency facilities vsr
brought into play and the vessel roS
surfaceward, to the infinite relief d
every one. Picture what might have
happened had she dropped into still /
deeper hole. This close shave Illus
trates the chances that are taken FRI
quently when our submarines M.
nnuvre, and possible disaster can "
guarded against only by making surs
that the hull is absolutely sound and
that none of the sea valves, &c, is d.
fective. And how does a testing doci
like that designed by Major Laurent
and copied by the Germans Insult T
against preventable mishaps?
He does It by permitting the submit
rine to be tested in port. either at
naval base or a building yard, undE
conditions that are no more trouble
some than those incidental 10 tn
working OF the usual dry dock Al
that is necessary is that there shall h |
a sufficient depth of water TO sub
merge the entrance to the testing J!
dock far enough to permit the under
water boat to be fioated into the grer
steel cylinder which constitutes th
unique feature of tho structure. Tm
cylinder is then sealed by q globur
caisson which Is seated and made tgs
Just like cork pressed firmly ins
the mouth of a bottle. When "
submarine has entered the cylin6
and has been duly centred. so thatE
cannot shift in any direction, the "
tube is filled with water which cor
pletely envelops the contained crS.
Then, by means of pumps, the pre-
sure exerted by this water is graduag .
raised so that the submarine is sui /
jected to a crushing force which ca
be made to correspond to that OF an'
actual submergence in the sea
Tests QuickIy Made.
All the while, men inside OF her ciA
watch for the slightest leak and J"
cate 1t promptly, and they can also
by means OF suitable instruments, o.
dect any reformation of the hull AM
whether or not the structure is per
manently affected or returns TO ~
erstwhile form when the EXTERN
pressure is relieved. They can IKE
wise work the boats pumps and
other things that show just how |"
mechanisms will function under 3,
vice conditions at any designed SUI
mergence. At a moments notice lN
ny OIOSldllC stEeSS OF the SA4
water can be dropped. because the o.
servers within the craft keep IN VOC
touch, by telephone. with the engln~
I'm charge of the external operations
With facilities OF this sort availaos
submarines can be tested quickly az,
easily. The Germans have prov"
that 1t is we'll worth while to ha"
auxiliaries OF this kind. and they ia"
similarly demonstrated that iesH.s
docks can be made large enough
deal with the biggest of modern SUI
aqueous torpedo vessels.
Our own submarine fioti,las 'a'''V'
be kept efficient and cannot De
amined periodically. as they shou'u ~
unless We too provide ourselves W..
kindred means 10 greater secu'''!'
The italians have developed even
more up TO date submarine auN"'aI.
In the shape of a combined seaso"'1,
tender and testing dock capao.t-
travelling thousands Of miles. ~.
tender or depot ship Is also a n'o..,
repair base, supply craft ana Nv. a
source OF relief crews for the "ea',.
personnel of the active boats o. INV
fiOtilla-