The motor of the torpedo, as illustrated, is composed of a number of
disk-shaped armatures fastened on the shaft, combined with the screw
propeller; the field magnets, being also of disk form, are arranged so
that the armatures revolve within close proximity, but not touching the
pole surfaces. This enables an exceedingly high efficiency and great
power to be realized from a motor of light weight. This construction of
motor is specially suitable for use in the equipment of torpedoes and
launches, and permits an increase of the power of the motor in either
of two directions, i. e., either by increasing the number of disks of
a given diameter upon the shaft, or by increasing the diameter of the
disks, both of these methods giving increased power in direct ratio
to the increase of size. The accumulator or secondary battery, c, is
especially designed to store the energy in a small space, and with
light weight, and so as to command an amount of energy representing
the power necessary for a speed of 25 miles an hour or more. In the
electrical circuit, between the motor and accumulator, variable
resistances and other governing devices are interposed, by which the
current passing to the motor is regulated automatically in accordance
with the speed of the motor, or with the electric pressure in the
circuit from the accumulator. A circuit closer or variable resistance
operating in the circuit is connected by the cable with a variable
resistance at the switch board, and operated by the current controlled
thereby. The force to the motor can be regulated, controlled, or
stopped at the will of the manipulator at the switch board placed at
the point from which the torpedo is dispatched. Signaling devices or
guide rods, O, for indicating the position and direction of movement
of the torpedo to the operator can be arranged to be raised and
lowered, through the medium of electrical appliances, P, at will, by
a current sent through the paying-out cable from the keyboard at the
base of operations. Fixed means or sight rods can be used, and hooded
incandescent lamps, O_{2}, can be carried by the signal or sight rods,
by which means at night or in the day the operator will be enabled to
direct the torpedo to the object of attack in spite of adverse or cross
currents, or a change in the position of the vessel under attack.
The body of the torpedo containing the machinery and explosive can be
arranged to be any desired depth below the surface of the water, and be
supported by a buoy as a shield, or be covered by a protection against
shot, the displacement of the torpedo being regulated in accordance
with the means employed for maintaining it the desired distance below
the surface. The torpedo can be ballasted and provided with fins
to offer the necessary resistance to the action of the propelling
machinery. The electrical paying-out cable, G, is shown in a coil in
proximity to the chamber at the bow, which is designed to carry the
explosive charge in a fixed or detachable magazine, arranged when
detachable to drop a determined distance, and to be fired electrically
by the operator or automatically.
Fig. 6 illustrates an apparatus in which a dynamo is operated by a
rotary engine having a throttling device controlled electrically by
the current passing through the discharging circuit of the generator;
the circuit of the generator is connected with the paying-out cable of
the torpedo, through the medium of the key board, in which a variable
resistance and regulating devices are employed for controlling the
operation of the torpedo. Electric magazines are shown arranged
to operate in the discharging circuit of the generator, and to be
connected with the appliances forming part of the equipment of the
torpedo through the medium of the paying-out cable, in conjunction
with which is arranged the circuit-closing devices of the switch board
under the control of the operator at the stations. Automatic electric
pressure regulators are used in the circuit from the source, so as
to reduce or regulate the pressure to some predetermined limit. The
circuit controllers and manually operative variable resistances upon
the switch or keyboard can have indicators connected with them. Under
such conditions, with the circuits and appliances upon the torpedo
constructed to a known standard, the control of such torpedo in all
its movements and operations is easy and certain. Such appliances
are especially designed for use upon men-of-war or steam or electric
launches when the torpedo vessels are not equipped with electrical
magazines. Fig. 5 illustrates a floating fort or battery equipped with
machinery, electrical apparatus, and torpedoes, as illustrated in Figs.
2 and 6. The floating fort or battery equipped with electrical or other
machinery for propelling can be anchored in suitable positions, or
moved from place to place to be in torpedo range of a fleet, or in a
suitable position for supplying torpedo launches with torpedoes, and
electric or other means of power.
Fig. 3 illustrates a steam launch, and Fig. 4 an electric launch
fitted with electrical appliances and compartments containing a means
for carrying and discharging electrical torpedoes. By the employment
of such means, and a well-organized system of coast defense, it will
be practically impossible for hostile vessels to land troops, or to
inflict a serious damage upon shipping or seaport towns. Any extent
of coast or estuary can be thoroughly protected by launches, light
vessels, and appliances operated from fixed electrical stations,
supplied with power and means of operation from any point, however
distant. For carrying such a system into practical operation, the cost
will, it is claimed, be but a tithe of what would be required for
placing an inefficient system of fixed mines and forts, or for building
men-of-war for coast defense, as men-of-war are practically defenseless
against a greater number of high-speed launches equipped with movable
and controllable torpedoes, the reasons for which are obvious, as a
sufficient number of such launches would cover a greater distinctive
range than the vessel which depended upon the range of its guns, or
those combined with uncontrollable torpedoes.