Year: 1877

lEHihtuclphia


Engineers who for the past few years
have paid particular attention to the
armor-plating of vessels, with view to
making them impregnable to the enemy's
shot above the water line and to their
torpedoes below it, as well as those who
have made these destructive implements
of warfare their special study, have been
long and patiently waiting for just such
a conflict as has recently been begun be-
tween the Turk and the Russian. Of
late years the invention of heavy guns
has been followed by the rolling of iron
or steel plates which could with difficulty
be penetrated by this artillery, and that
again by the manufacture of still more
powerful guns, until limit has been
reached caused by the non-buoyancy of
the heavily-weighted floating batteries.
Naval authorities, since the sinking in
mid-ocean of the Captain, have been
rather chary about the weight of the
armor placed on vessel, and it is likely
that the experience of the war Just COM
menced will teach some of the stronger
naval powers the folly of spending mil
lions of dollars on single iron-clad,
which in a moment may be crippled by
torpedo, or which may go down with all
on board in a heavy sea, simply from her
own unwieldiness. r3


The science of defending harbor or of
rendering a river impossible by the
means of stationary torpedoes, and of
bringing destruction upon the iron-clad
fleet of an enemy by movable ones, has
made great advances with the last few
years. There are two classes of these
submarine mines, respectively fixed and
movable, and the methods of discharge
in the stationary ones, as well as the
modes of locomotion in the others, are
varied to suit the surrounding circum-
stances. The primitive torpedoes were
moved on the sea bottom, allowed to float
few feet below the surface, and ex-
ploded by meausof percussion caps which
were fixed on their upper ends and struck
when the vessel scraped over them. These
were fitted only for certain purposes, such
as blockading the entrance of harbor
against the passage of the ships of an
enemy, and they were Objectionable be-
cause while one of the combatants was
kept out of harbor, the other wasabout
as effectually kept in, as the torpedoes
were generally laid in so great hurry
that sufficient time was not allowed for a
complete chart, and, even with ismade,
the currents of a harbor might so shift
the moorings of torpedo that friendly
vessel would be sunk. sI...I


Later, torpedoes were fixed in their po-
sitions, but instead of being fired by per
cussion were exploded by means of an
electromagnetic battery ON shore. In
the various details of connection with the
shore, internal mechanism and explo.
sions, there is great difference in the
torpedoes of different governments and
manufacturers. In some gunpowder is
used, in others nitro-glycerine, dynamite
or gun-cotton. Sometimes each torpedo
has distinct connection with the shore
while in others the wires meet at some
one point and all are conveyed to shore
within single cable.


These electric stationary mines have
some decided disadvantages, among which
is the possibility of the cable or cable:
connecting them with the shore being
grappled and cutby a boat party, thereby
rendering the torpedoes perfectly useless
In this variety of torpedo it is necessary
to know the exact moment at which the
vessel is passing over the mine, and thi'
is ascertained by two experts, one o.
whom is located ON shore, opposite thu
line of torpedoes, and who closes tht
electric circuit when vessel crosses hi
line, thus giving notice to another in
dividual, whose observatory is so located
that he can see the ships coming bow on
and by means.of a transit or theodolit,
with graduations corresponding with th'
lines of sight to the several torpedoes h,
is observing, he is enabled to tell whethe
the enemy's ship is sdirectly over torpe
do, to the right or left, or 50 far ava,
that the explosion of it would do no dam
age Should, there be another line o
torpedoes the same mode of operation i
followed, so that it becomes almost al
impossibility for the passage to be mad
without accident. Another advantag
of torpedoes of this kind is that afte
hostilities have ceased, and, for the bene
fit, or rather the protection of commerce
the Instructions are to be removed, Their
is far less danger incurred by those whit
raise them, than there would be wer
the ordinary percussion torpedoes used
|