PREPARATION OF TORPEDOES.
SERVICE TORPEDO.
=Pattern D.—Plate I.=
=Priming the Service Torpedo.=—Take the torpedo out of its box; remove
the screw-cover of the case and take out the wet gun-cotton found in
the primer-case; wipe the primer-case dry and insert a primer of 16
one-half inch blocks, or 4 two-inch blocks of dry gun-cotton.
The wet gun-cotton removed from the primer-case is to be put in one of
the empty exercise torpedo-cases and dried when opportunity offers.
Wipe the screw-thread carefully and screw down tight the cover on its
washer, taking care not to cut it, using the open-end wrench provided
for the purpose in the supply-box. _It is absolutely necessary that
this case be closed water-tight._
=_Note._=—It is not advisable to prime torpedoes for a much longer
time before using than the exigencies of the service require, although
experiments at the Torpedo Station show that service gun-cotton
torpedoes may remain primed for three months, under service conditions,
and yet be relied upon to explode.
=Testing the Detonator.=—Select a detonator, brighten the ends of
its legs and attach them to leading-wires. _Put the detonator in
a safe place_, connect the leading-wires to the terminals of the
testing-magneto and turn the crank. Rattling of the armature will
indicate continuity of the circuit and is presumptive evidence that
the detonator is good. The wires from the detonator can be taken to
the binding-posts T, T of the firing-key of the A machine and tested, a
deflection of the needle furnishing proof of continuity (_Plate XVI_);
or they can be taken to the terminals of the C machine which will
indicate continuity by the striking of its gong. (_Plate XVI_).
=Splicing on the Detonator.= (_Plates I and II._)—The detonator
should now be spliced to the spar leading-wires. In splicing on the
detonator, so arrange the length of wire that the spherical rubber
packing can be placed on the leading-wires five inches from the bottom
of the detonator-case, the splices being between the detonator and
the packing. Remove the water-cap from the screw-cover of the case.
Strip the braiding and rubber tape from the leading-wires for at least
six inches from their ends and put on a neat whipping, which shall be
outside the packing.
Reeve the ends of the leading-wires through the water-cap and rubber
packing. Remove so much of the insulation as may be necessary, for
making the splice, from the leading-wires and from the legs of
the detonator; brighten the wires and place the insulation of the
detonator-legs alongside that of the leading-wires, with the ends of
the insulation flush, and expend the bare detonator-legs in turns
at right angles around the leading-wires. Turn the ends of the
leading-wires back over the splices, and trim off the ends. _One splice
should be one-half inch from the detonator and the other one inch from
the packing._ Insulate from metallic contact the splice nearest the
packing with twine and pass several turns about the wires until the
detonator is reached, where the end of the twine is secured. A strip of
okonite tape can be used, taking care that the insulation is not too
bulky. (See sample splice in supply-box).
=Fuzing the Service Torpedo.= (_Plate I._)—Having lined the holes of
the dry blocks with the rectifier, to be found in the supply-box,
enter the detonator through the hole in the cover and push it in until
the packing is seated; screw up the water-cap hand-tight. Provide the
spindle, to be found in Box 53, and secure it to the torpedo-case.
=Shipping the Secondary Spar.= (_Ship‘s._)—Enter the end of the
secondary spar in the loop of the outer band, and push in until the
key-way is abreast the slot in the loop of the inner band; then put in
the key and stop it in.
=Shipping the Service Torpedo.= (_Ship‘s._)—Insert the stem of the
spindle in the outer end of the secondary spar and push it home as far
as the shoulder. Put in the torpedo-pin and stop it in.
To prevent the strain of towing from starting the splice, turn
a cuckold‘s-neck in the spar leading-wires, and lash it to the
secondary spar or to the spindle, clear of the torpedo-case. The spar
leading-wires should then be led in along the ship‘s spar, abaft the
topping lift, and stopped to it at intervals of about four feet.
=Fuzing and Shipping the Service Torpedo, and Shipping the Secondary
Spar.= (_Boat‘s._) =Pattern B. Boat-Fittings.=—See that the
elevating-arm points aft. Rig in the main spar clear of the guide-ring.
Point the inner end of the secondary spar through the guide-ring,
the outer end resting on the rail. Reeve the leading-wires through
the guide-ring from forward aft, and fuze the torpedo. Then ship
the torpedo in the secondary spar, securing it by the torpedo-pin,
which must be stopped in. Turn a cuckold‘s-neck in the leading-wires
and stop it to the secondary spar or to the spindle, clear of the
torpedo-case. Slew the secondary spar in position, butt aft. Reverse
the elevating-arm, by revolving it downward, until the guide-ring is in
line with the swivel-crutch and heel-rest, carefully tending the inner
end of the secondary spar by a line bent on. Ship the secondary spar
in the main spar, by rigging the latter out or in, and secure it by a
toggle, which must be stopped in.
The boat spar leading-wires are rove through the main spar. To
facilitate this, a reeving-line and weight, found in the supply-box, is
rove through the main spar, before the secondary spar is shipped; one
end of the line is secured to the heel-bolt, and the other around the
spar abreast the wire-hole.
When the secondary spar is shipped, bend the end of the leading-wires
to the reeving-line, rig out the torpedo until the heel of the spar is
conveniently placed for hauling on the after end of the reeving-line,
and reeve the leading-wires through the spar, being careful to avoid
chafing the insulation.
When the contact spar leading-wires are used they must be rove through
the main spar, from aft forward, before fuzing the torpedo.
The spar leading-wires from the heel of the ship‘s spar are taken
to the terminals abreast the heel of the spar; from the heel of the
boat‘s spar they are taken directly to the C machine, or to the
firing-battery, a hand-firing key being interposed when the battery is
used. (_See Plate XV._)
_No connection, however, is to be made with terminal, machine, or
battery, until the torpedo is submerged and at the proper distance from
the side of the ship or boat._
=Testing the Circuit from Ships.=—After the torpedo is submerged the
circuit may be tested, to do which connect the spar leading-wires
to their proper terminals and connect the binding-screws T, T, of
the firing-key, to the proper permanent wires. Place the firing-key
as directed for testing the detonator, ship the crank of the D.
E. machine, turn rapidly with the sun, and press the key T of the
firing-key. A deflection of the compass-needle will indicate that the
circuit is complete. (_See Plate XVI._) Or, the testing-magneto may be
used to test the circuit.
_The firing-battery must not be used to test the circuit._
=To Fire.=—Make connections with the firing-battery, or with the A
machine (_Plate IX_). When using the battery, close the hand-firing key
at the moment it is desired to fire. When using the A machine, press
the key F of the firing-key, and keep it down; turn the crank of the
machine rapidly, and at the instant it is desired to fire, press firmly
the key T of the firing-key (the key F being already down).
The Service Torpedo must be immersed 10 feet, and from ships may be
safely exploded at 35 feet from the side.
=To Test the Circuit from Boats.=—The spar leading-wires are brought
directly to the machine, (_See Plate XVI_), _but not connected until
the torpedo is submerged_, when the circuit may be tested by connecting
it to the binding-screws of the C machine, turning the crank of the
machine and pressing the key T, as for testing the detonator. Or, the
testing-magneto may be used to test the circuit.
_The firing-battery must not be used to test the circuit._
=To Fire.=—Make connection with the battery (_Plate XV_), or with the
C machine (_Plate XVI_.) When using the battery, close the hand-firing
key at the desired instant. When using the C machine, manipulate the
keys as directed for the firing-key of the A machine.
The Service Torpedo must be immersed not less than 10 feet, and may be
safely exploded at a horizontal distance of 22 feet from the boat.
EXERCISE TORPEDO.
=Pattern D.—Plate II.=
=Priming the Exercise Torpedo.=—Remove the transportation thumb-screw
and loosen the thumb-screw on the lug of the hinge. Throw back the
cover, replace the second wet block of gun-cotton from the top with
a dry 2-inch block, or four ½inch blocks, and put the cover back in
place; insert the spindle, to be found in box 53, through the loops on
one side and screw down taut against its shoulder; screw down also the
thumb-screw on the lug of the hinge. _It is absolutely necessary that
this case be closed water-tight._
The wet gun-cotton removed is to be placed in one of the empty exercise
torpedo-cases, to be dried when opportunity offers.
=_Note._=—Do not allow the dry primer to remain in the exercise torpedo
any considerable length of time before use, as it may absorb enough
moisture to prevent detonation.
The detonator is tested and spliced, and the torpedo fuzed in the same
manner as directed for the Service Torpedo.
=Shipping the Exercise Torpedo.=—To be done in the same manner as
prescribed for the Service Torpedo.
The Exercise Torpedo may be used from either a boat‘s or ship‘s spar.
It may be safely exploded at an immersion of 5 feet, and a horizontal
distance of 20 feet.
PREPARATION OF THE CONTACT TORPEDO.
=Pattern D.—Plate V.=
=To Convert a Service Torpedo into a Contact Torpedo.=—Attach a
circuit-closer, Pattern B, to the frame on the lower head of the
torpedo by screws through the lugs.
=Testing the Circuit-Closer.=—Remove the water-cap and spherical
rubber packing from the side of the circuit-closer; remove its
screw-cover; take out the inner plunger. Remove the braid for a few
inches from the longer leg (insulated double-conductor cable) at the
outer end of the contact spar leading-wires, whipping the braid.
Remove the rubber tape from the conductors, and pass them through the
water-cap and packing and through the cylinder of the circuit-closer.
Remove the insulation for one inch, brighten and lay up the naked wires
and connect them to the binding-posts of the circuit-closer, taking
care that the bare ends do not project far beyond the binding-posts.
Seat the inner plunger, hauling on the wires at the same time, so as
not to leave any slack wire in the cylinder. Set down the water-cap on
the packing in the side of the circuit-closer. Replace the diaphragm,
friction-plate and screw-cover. Remove the insulation for one inch
from the shorter legs at the outer end of the leading-wires, and
bend the naked wires together temporarily. Connect the inner ends of
the leading-wires with the terminals of the testing-magneto, or of
the C machine. Close the safety-break. Remove the safety-pin from
the circuit-closer and press down the contact-arms. Under these
circumstances a test with the testing-magneto, or with the C machine
should show continuity. Release the contact-arms and put in the
safety-pin. A test should now show no continuity. After this test the
safety-pin must not be removed until just before submerging the torpedo
prior to firing.
_It is absolutely necessary that the circuit-closer be closed
water-tight._
=Priming the Contact Torpedo.=—Proceed as in priming the Service
Torpedo.
=Fuzing and Shipping the Contact Torpedo, and Shipping the Secondary
Spar.=—Proceed as with the Service Torpedo, except that the contact
spar leading-wires must be rove through the main spar, from aft
forward, before fuzing the torpedo. The detonator must be spliced to
the short legs of the leading-wires.
=To Test the Circuit.=—The torpedo having been submerged, connect the
inner ends of the leading-wires to the testing-magneto, or to the C
machine. Close the safety-break and the hand-firing key and test. Under
these circumstances continuity should be found.
=To Fire at Will.=—Connect to the firing-battery, close the
safety-break and, at the desired moment, close the hand-firing key.
=To Fire on Contact.=—Connect to the firing-battery. Close the
safety-break. When contact is made the contact-arms will be forced in,
and the torpedo will explode.
=_Note._=—The safety-break should be habitually left open, being
closed only just before it is desired to put the circuit in condition
to fire by closing either one of the two remaining breaks—that in the
hand-firing key, when firing at will, or that in the circuit-closer,
when firing on contact.
IMPROVISED TORPEDOES.
Torpedoes may be readily improvised from kegs or casks pitched outside.
The fuze should be put in place before filling with powder, in order
that it may be near the center of the charge. The spar leading-wires
pass out through the close fitting scores in the bung. The latter,
after being secured in its place, should be pitched over thoroughly,
and weight added to the whole, in order that it may be readily
immersed. For exercise torpedoes, bottles, oil-cans, etc., may be used.
An excellent composition for rendering the bung and the entrance of the
leading-wires water-tight is made by melting together 8 parts of pitch,
1 of beeswax and 1 of tallow. It is to be applied while fluid.
In order to burn all of the powder in the torpedo, a spindle, to
contain the fuze, should be made on board of wood, following the
general form of spindle in a gunpowder torpedo, and using a wrapping of
cotton cloth, bunting, or paper, to prevent the powder passing through
the flame-holes and choking up the spindle.
=Splicing on the Fuze.=—To splice the fuze to the spar leading-wires
so arrange the length of wire that the fuze will be entered in the
spindle, reaching well into the torpedo-case when the entrance for
the wires is closed. The leading-wires must be stripped of covering
exterior to the insulation, to a distance extending to just outside
the entrance. At this point the outer wrapping on the wires should
be secured by a good whipping. If the outer wrapping on the wire is
admitted inside, it will, after a time, act so as to introduce water to
the charge.
To make the splices, strip the insulation from the leading-wires for
about an inch, and brighten them. Brighten the fuze-legs and twist them
around the leading-wires in a manner similar to that employed in the
Service Torpedo, arranging the splices, however, so that they shall be
at equal distances from the top of the fuze. Cut off extra ends and
lay the splices in the scores of the fuze-plug; turn the insulator
down over them, and secure it with the insulator fastener. (See sample
splice in supply-box).
USE OF THE PERMANENT WIRES AND ELECTRIC SWITCHES.
=Connecting.= (_Plate IX._)—The connections with the firing-battery
are as follows:—one wire from each switch is connected to one battery
terminal, and the common-return wire, with the hand-firing key
interposed, is connected to the other battery terminal.
The connections with the firing-key of the A machine are as
follows:—one wire from each switch is connected to one binding-post,
marked T, of the firing-key, and the common-return wire is connected to
the other binding-post of the firing-key, also marked T.
When electric switches are used an intelligent and careful person must
be stationed at each switch, the index of which must be kept pointing
toward “Battery off; connection through,” except when it is desired
to prepare the circuit for firing any torpedo, when the index must be
turned so as to point toward the torpedo which is about to be fired.
The circuit for firing any single torpedo may thus be arranged; or, by
moving the index to point toward “Battery on both” the circuits will be
prepared for firing the two attached to that switch.
By a proper manipulation of the switches the circuits may be prepared
so that any one, two, or three, or all four of the torpedoes may be
fired simultaneously.
It must be borne in mind, however, that the electric switch is only a
commutator for establishing the paths of the currents and that it must
not be used as a firing-key.