The Works Of Messrs. Schneider And Co.

XXXV .—TORPEDO - LAUNCHING TUBES. f 11HE Schneider-Canet system of artillery includes J- a series o£ torpedo-launching tubes, of varions patterns, fulfilling the numerous conditions required in service in modern fleets. A special section of the artillery department is reserved for this work. The tubes are of gun-metal or of steel, as may be found expédient, and they can be adapted for launching any type of torpedo now in service in varions countries. The series may be divided into two principa] classes : i. SCHNEIDER-CANET TUBES ABOVE WATER-LINE. The. large number of patterns of this class differ one from the other only in their mountings, which vary in design, according to the conditions of service and the type of ship on which they are fitted. They can, more- over, be extended in front by a spoon-shaped guide, which insures the horizontal position of the torpedo being retained when it pénétrâtes the water after launching. The following details are common to all the types : (j) The clelicate mechanism carried by the torpedo itself, and especially the screw which propels it, are secured against all damage that might be caused either by the sudden influx of compressée! air or by the déflagration of powder gases. (k) The device for closing the rear of the tubes. This is of a special design, resembling the interrupted threads of a breech-block ; a progressive turning of the closing arrangement insures a tightness of the joint under the pressure at wliicli firing takes place. Some of these devic.es are closed mechanically, reducing the efforts to be developed on the governing crank. Figs. 770 and 771, Plate CXXXIII. (l) For the tubes supplied witli compressée! air-firing device, the mechanism for launching with powder is also delivered, unless otherwise stipulated. (<Z) Smokeless powder can be used when required, so as to prevent an enemy from noticing the exact instant a torpedo is fired, and from aiming at a dangerous part of the ship. (m) Firing can be effeeted by a percussion, or an electric, fuse, and the firing device can be worked mechanically or by electricity at will. (/) The Schneider-Canet tubes are provided with automatic apparatus which render impossible, in current manœuvres, any mistake in the order of succession of the varions actions. (</) The tubes are fitted with luminous sights which render night service possible ; the deviations resulting from the speed of the target, and the ship itself, being corrected automatically. From the above remarks, it will be seen that it will prove sufficient, to obtain a clear idea of the Schneider- Canet system, to give the details of one tube, a special description being added of each of the principal types of mountings. FIXED TUBES. (n) Fixed Tube on Deck in the Bow of Torpedo- Boats.—The tube may be made of gun-metal or of steel, the thickness of the walls, and consequently the total weight, varying according to the metal used. It consists of two cylindrical rings, the length and inside diameter of which dépend upon the type of torpedo to be used, and which are fitted together by means of flanges and bolts. The top centre line on the inside surface is made with a groove, in which the torpedo tits ; this serves as a guide during firing (Fig. 772, Plate CXXXIII.). On the tube are the following parts : The breech-closing arrangement, which is, broadly speaking, like that used for guns ; its operation is there- fore familiar to gunners who are already accustomed to the service. The closing device consists of a circular plate, made sliszhtlv convex to the rear, which fits to the tube, and is made to pivot on a vertical hinge ; round its circumference is a series of continuons and interrupted threads, similar to those of gun breech-Blocks. This disc is strengthened by a certain number of ribs ; it carries in the rear a fixed handle, and the firing bolt, to be described later. The tube ends at the rear in a ring cut with a rabbet, in which the disc fits when it is closed. In this rabbet is formed the joint that insures tightness during firing, the disc bearing against a special plastic ring placed in the rabbet. To close the disc and obtain the required contact, a round ferrule is screwed in the projection of the rabbet, and is made to turn round its centre ; on its inside are cut a series of continuons and interrupted threads, which correspond exaetly to those on the disc, in such a manner that it is sufficient, in order to fix the disc to the tube when it is at the bottom of the rabbet, to turn the ferrule to a degree corresponding with the pitch of the continuons threads, this action being transmitted by a toothed sector fitted to the outside of the ferrure, and by a pinion placcd in the thickness of the ring in the rear of the, tube. The whole system is worked by a crank. To open the disc, the crank is turned round to disengage the continuons threads, the disc being then brought to the