This contains 300 feet of insulated double-conductor wire cable. The inner ends of the cable are connected to binding-screws on the sides of the reel, where short wires are to be attached, for making connections with batteries, etc., after the requisite amount of cable has been unreeled. A handle is becketed to the cover of the box, to be used in reeling up the cable. The binding-screws must be kept free from rust (no oil to be used in cleaning), and must be occasionally turned to keep them from setting. The cable, as now issued, consists of two cores, each core composed of seven No. 22 A. W. G. copper wires of not less than 95% conductivity, coated with tin and laid up in a strand. Each core is separately insulated with okonite composition to an external diameter of ¼ inch and is wrapped with tape soaked in okonite composition. The two insulated cores, laid side by side, are covered with hemp braiding to protect them from chafe. The resistance of the core is 2.2 ohms per 1000 feet. The cable in the reel box is for general use and to replace disabled permanent wires. It must never be subjected to a strain of over 100 pounds, nor jerked or hauled in from any length, but under-run. The cable must be stowed in a cool, dry place. SHIP‘S WIRE-BOX. This box is marked “Wire-Box—Ship‘s.” It contains four spar leading-wires of insulated double-conductor copper wire cable, 70 feet each in length, precisely similar to that found in the reel box, and two machine-connecting wires 12 feet each in length. The spar leading-wires are to connect the torpedo with the terminals of the permanent wires. To guard against mistakes in making connections those for use on the starboard side are painted green and marked with one knot and those for use on the port side are painted red and marked with two knots. The machine-connecting wires are insulated wires for connecting the D. E. machine, Pattern A., with the firing-key and for general purposes. BOAT‘S WIRE-BOX. This box is marked “Wire-Box—Boat‘s.” It contains the same articles as “Wire-Box—Ship‘s,” similarly marked. CONTACT SPAR LEADING-WIRES. =Pattern B.—Plate V.= These consist, practically, of three insulated copper wire cables which lead, in use, as follows:—1st. wire, from the detonator to one terminal of the battery; 2nd. wire, from the circuit-closer to the second terminal of the battery _via_ the safety-break; 3rd. wire, branching in two legs at its outer end, from the detonator and the circuit-closer to the second terminal of the battery _via_ the hand-firing key and the safety-break. The safety-break and the hand-firing key are connected to their proper leads by wires of convenient length to permit placing the battery out of the way when connected up.