The Winslow mail., 1910-12-10

IL by which dangers to their
crews can be reduced to a
minimum. Those who are used to
serving in these deadly little craft
will tell you that these dangers are
not so great as is usually imagined,
and that the loss of life from acct
dents has really been comparatively
small.
The two great dangers are COLI
sion and explosion, and special at
tention has been given to methods
that will prevent loss of life in case
of accident from these two sources.
When the submarine Is submerged
it is really half blind, for the peri
scope Is only a makeshift eye, but
even this has been greatly improved
Formerly the lens in use only allowed
half the horizon to be examined, un-
less the periscope was turned round.
1t could therefore happen that ship
might come up unnoticed and strike
the submarine before 1t could dive
to safety Now, however, a new lens
has been devised which gives COM
plete view all round, so that an ap-
preaching vessel can be seen from
whatever quarter 1t comes. The peri
scope Is the eye of the submarine.
It's vertical telescope tube looks like
very thin smokestack, extending 10
feet above the submarines bridge
and it's top part contains the so-called
eye, which sends down images of the
outer world to the interior Of the SUBJ
marine, either by reflection or refrac-
tion. One system Is almost as good
as the other. The reflection apparatus
has two mirrors at As degrees at the
two extremeties. The apparatus by
refraction has two prisms of total re-
fection, as in a camera. Behind the
top one a mirror sends down the
image that can be enlarged-like the
telescope attachment to a camera
but both systems have the disadvant-
age of looking on the world through
pinhole.
Suppose the "eye" be fixed north
Those in the submarine get glimpse
due north. To glance a few degrees
on either side the whole tube must be
turned or else the eye alone. In the
first case-if the tube does not twist
or grtp-the image turns with 1t and
observers have to move around the
table. If the eye alone be turned the
lower prism or mirror remains fixed
The image, consequently, shows all
objects inclined at the angle of the
eyes turning.
For years past the French admir-
atty has never ceased to hunt for
something better. The navigation
of submarines under water absolutely
demanded an apparatus capable of
disclosing simultaneously the whole
circle of the horizon-plus a tele-
scopic magnifier for the object to be
carefully examined.
And here we are on the delicate
ground of a state secret. They have
found their apparatus. 1t is known,
too, that they got upon its track by
seeking to utilize an annulary prism
devised by Colonel Manjin for the
taking Of circular photographs Of the
horizon from captive balloon. This
Is all we really know of the construc
ton of the machine that is to put
French submarines on a footing of
such enormous superiority that the
mind does not at first grasp the
meaning of 1t. But the effects pro-
duced by the machine have not been
kept SO secret
In Brest three submarines and
three submergibles were fitted with
the apparatus at once for experiment
and extraordinary tales are told of
exploits under water.
Up to within a mile of it's prey
the submergible floats on the surface
like a simple torpedo boat Then,
fearing to be seen, it sinks and con-
tinues navigating six feet under wa
perfected periscope. Within 500
yards of the doomed ship they pull
In the telescope tube and navigate
a short time by the compass.
When they Judge they are within
500 yards they push the tube into
the air again-just high enough to
let them see their prey. 1t is prac-
tically invisible to people unsuspi-
cious of it's presence in that particu-
lar spot At 300 yards the torpedo is
shot and what happens is what hap
pened to the Russian feet so often.
These are submergibles, 112 to 220
feet long, semiseagoing and furnished
with both steam and electric engines.
Their normal plane of travel being
on the surface just like a torpedo
boat their primary motive power is
the steam. These steam engines run
the dynamos to renew the motive
power of the electric engines and all