The crew having been stationed at their respective posts, the handles
having been shipped on the tow-reel, the tow-line is then reeled up until
the torpedo will launch clear, and swing out under the leading block on
the yard. Hold the torpedo by the handspikes, and take off the handles of
the brake. In swinging out, care should be taken that in starting from
the deck the fore slings do not foul the fore top lever. The stern of the
torpedo can be steadied by keeping a slight strain on the buoy-rope. The
safety-key line must be kept clear, and not checked, or it might break
the stop and draw the safety key before intended.
The buoys must be placed in a proper position, and hands stationed by
them to launch them overboard the instant the torpedo takes the water.
It would be better to stop the screw, if circumstances would allow of it,
when lowering the torpedo and buoys into the water, to prevent the chance
of the buoys fouling the screw. The torpedo, on reaching the water, will
_immediately_ diverge clear of the ship; the buoys being launched, as the
strain comes on the buoy-rope, they will be towed clear away from the
screw, and full speed may be put on at once. The men at the handspikes
must veer steadily, occasionally checking the torpedo, that it may be
kept near the surface, and not allowed to dive, which it will do if the
tow-rope is slacked up altogether, and then a sudden strain brought on it.
[Illustration: DRAWING 4.]
Eventually it will come to the surface, when the bow is pointed up by
the strain on the tow-rope; greater the speed the more quickly will it
be brought to the surface. In shallow water this should be particularly
attended to, as in diving it might strike the bottom and injure the
levers; and if the safety key has been withdrawn, explode; moreover it
brings an undue strain on the tow-rope. The torpedo can now be gradually
veered out to the distance required, the safety-key line so attended,
that a sufficient strain is kept on it as not to allow of a long bight
of line dragging astern of the torpedo; at the same time having due
regard to the strength of the yarn by which the line is stopped to the
handle of the torpedo. The distance veered must depend upon the nature
of attack. The tow-line should be marked with knots every ten fathoms;
under some circumstances the torpedo would be close to the ship until
passing the enemy (_see_ Tactics); at other times veered to 40 fathoms it
will be found most suitable. The full divergence of 45° is obtained up
to 50 fathoms, beyond that the bight of the tow-rope in the water drags
the torpedo astern unless the tow-rope is triced much higher up, which
has its disadvantage; 40 to 50 fathoms of tow-rope gives the best command
of the torpedo, veering 2 or 3 fathoms of tow-line suddenly will always
sink the torpedo some feet below the surface. Should it become necessary
to use the torpedoes with a stern-board they can be so used, but in
this case the port torpedo is used on the starboard bow and starboard
on the port; all other arrangements being exactly the same. In rough
weather, advantage should be taken of the roll, and the torpedo allowed
to swing out from the yard, and be let go by the run, checking the
tow-rope immediately the torpedo is in the water. It is not absolutely
necessary to ease the vessel when launching, the torpedo can be launched
at full speed. In the event of its being found necessary to cut adrift
the torpedo, in consequence of coming suddenly across a friendly vessel,
the tow-rope should be cut near the brake, and if the buoy-rope has been
rove through the large stern-ring, the torpedo will sink and be lost, the
buoy only remaining. If the buoy-rope has been rove through the small
stern-ring, the torpedo will be suspended by the buoy-rope; and should
the safety key not have been withdrawn, can be recovered with safety.
In the event of wishing to recover it when the buoy-rope has been rove
through the large ring, a toggle must be lashed on the tow-rope abaft the
leading block on the yard, when it can be recovered by the buoy-rope; as
a general rule, it will however be found best to expend the torpedo, and
not attempt its recovery. By slacking the tow-rope roundly and stopping
the vessel, a friendly ship can pass over the bight of the tow-rope
without striking the torpedo; but this is rather a delicate operation,
particularly if the safety key has been withdrawn.