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.