The sun. [volume] (New York [N.Y.]) 1833-1916, 1915-02-21

h''N' - NV IL TGHn
II Is to make her rise,
1t has been said that a man walking
from one end OF "a submarine to IN.
other would. in ali probability. cause
nor To- plunge dangerously. so delicate
X the state Of cQuipoise when totally
submerged. Whatever MAY have been
tho case in the carly types. # Is GER
fanny not so now. So eteadv urc
modern submarines when running be-
low h surface. especially those uf
the British. Russian. French and
japanese and German navies. that the
long up and down hill glider which,
with some boats. used 10 amount TO
yaws of from 20 Ia 30 fcet. have now
been reduced 20 a few feet in so many
hundreds Of yards. In fact. his switch
ha'k motion il almost unnoticcablp
except when the submarine Is being
swung around at u sharp angle. In no
case. however. is IL sufficient materially
20 affect the firing Of the torpcdoes.
the reserve ~buuyanCy Of a SUBJ
marine in the awash conditioner
owing trim. a. Il is called in the
British fiotillas-is necessarily very
small. amounting to little more than
two or three pounds in a thousand.
which in "A 800 ton vessel means "A
difference ~ only about 100 gallons OF
sea water between the ability To float
and the i~nevitability Of sinking. Any
material Increase IN TIE small margin
OF what * known as positive buoyancv
must he accompanied ny a correspond
ing increase I'm the power OF propul-
sion, otherwise Il would bc quite i'm
nngCihIn 20 Irfx. lar ,,,.a l.
other word TO overcome the vessels
natural tendency TO float on the sur
face.
tor these and other reasons n sub
marine when running submerged is I'm
such a delicate state OF equipoise that
any sudden increase or loss OF weight
would upset the balance and so cause
the vessel TO either dive or rise with
dangerous rapidity.
This would he the effect produced
when a torpedo was discharged were
provision not made to counterbalan-e
this sudden loss Of weight by mea ne OF
compromising tanks, into which suf-
iicient water - pumped to compensate
for the loss of weight incurred by the
discharge OF each TORPEDO.
Many submarines are also fitted
with bow and stern trimming tanks.
into which water can lie pumped in
such a manner as to correct any ten
dency of the vessel Ia Loaf too high
or low at either extremity.
OF the many complicated problems
surrounding submarine boat construc-
ton the motive power and lropelling
engines have been in tac past. and are
SIN, the most profound puzzles.
steam. compressed air. electricity.
petr ! and heavy oil have all been us a
with varying results since first this
type of vessel cam" into being and
many curious engines FOR using these
prime I'm conjunction with
each other and with chemical COM
pounds have been evolved nv in
gent"us Inventors.
About steam and compressed air
little need hc said. for although given
"A good trial, especially 10y tho French
naval authorities. they were abandoned
some years ago in favor Of "A cotnhina-
ton 80 petrol 9nd electric engines.
which in turn have given place 20
more powerful machines using heavy
oil ami electricity. Steam is. however.
again being used in conjunction with
turbine engines for surface propulsion.
Tho carrying OF large quantities OF
petrol or heavy oil is under all cir
CumStanCes attended with % certain
amount of risk. and wnen many tons
have to be carried in a confined
space, as In a submarine. this risk is
mere than doubled, as he sllghtes'
leakage when the vessel is submerged
would mean that "a powerful Explosive
mixture of petrol and air would be
made.
II j. also quite impossible. for
obvious reasons 10 use a petrol engine
when running submerged, y second
motive power, an engine, with It's adj
ditiunal space and weight. has to be
carried TO drive the submarine when
under water. For this purpose cleo
trlc!ty is used In almost al types. But
Electricity. again. has many draw
backs: " costs IN wcicht naarly thirty
times more than other motive powers
and Is extremely dangerous, for should
salt water in any way gain access TO
the storage batteries chlorine gas
would be iven off in large quantities,