The Works Of Messrs. Schneider And Co.

262 MESSES. SCHNEIDER AND CO.’S WORKS. by two steps, the non-reinforced part of the tube being in (39j in.) maximum. During recoil, the liquid in the front the shape of a truncated cone. The force of recoil is transmitted direct to the trunnion-ring by the jacket, the latter being made with dovetails, which secure it to the trunnion-ring and to the tube. In order to prevent the sliding of the tube during firing, the bearing of the dovetails is made more secure by allowing a slight longitudinal shrinkage to the jacket and trunnion-ring. The breeeh-block is on the Schneider-Canet system, with interrupted screw and composite obturator. All the parts can be put together and taken to pieces without the help of any special tool. The gun can be fired with percussion, or an electric, fuse. It lires ordinary shell, weighing 140 kilogrammes (309 Ib.), and armour-piercing projectiles, weighing 164 kilogrammes (362 Ib.). The charge consists of prismatic brown powder, and weighs 87 kilogrammes (192 Ib.); the corresponding density being .94 (equals weight of powder divided by the capacity of the powder-chamber). The mounting is central-pivoting, with hydraulic recoil and automatic return by gravity. It consists of a carriage, with slide and transom of cast steel, and a cast-iron bedplate ; it weighs in all 33,200 kilogrammes (31 tons). The trunnion centre is 2,200 metres (86.614 in.) above the floor level. The carriage rests on the slide with the interposition of cylindrical rollers, on which it is guided in its travel, so as to prevent all deviation or raising of the system ; it carries at its lower part two recoil cylinders, ■each with a piston fitted to the front of the slide. The slide is made with an incline of 4 deg. (7/100), and consists of two parallel cheeks with a cross-beam in front; it is joined to the transom, which turns round a pivot on a set of free rollers kept in place by rings. Cramps fixed to the transom hold a string-piece on the bedplate, and pre- vent the raising of the slide during recoil. The bedplate forms a pivot, and the string-piece above referred to serves as a circular rack for lateral training. It is bolted on wood beams to a masonry foundation, the weight of which insures the stability of the system. The range of elevation is from — 7 deg. to + 25 deg., and the required elevation is given by cranks working a shaft, and a set of gearing which acts on a toothed sector fitted to the gun. In the arrangement of the gearing, means are taken to insure a smootli working of the gun during elevation, as well as to prevent all shocks on the mechanism when there is prépondérance of the muzzle. As the shaft on which the cranks are keyecl is fitted to the slide and not to the ■carriage, the men need not leave the cranks when the gun is fired. For lateral training, the range runs through 360 deg., and this is obtained by cranks working a shaft and a set of gearing that engages the rack on the bedplate ; this same mechanism serves to run in the gun by hand- power, after disengaging a pinion to prevent the mounting from revolving; and for this a set of gearing with plate- chain transmissions is provided. The recoil cylinders are f'ormed for constant volume, and with loaded valves. They limit the recoil to 1 metre part of the cylinders acts on the valve and opens it, giving a passage from the front to the rear, a small part of it flowing through two vents in the piston. When the recoil is spent, the valve closes, and the liquid in returning from the rear to the front, passes through the two openings, thus setting up a résistance which Controls the running out of the gun, that takes place automatically, through the incline of the slide. The cylinders are placée! at the lower part of the carriage, in order to insure the préserva- tion of the rods and prevent losses in liquid. This causes a greater momentum in running out than would be the case were the cylinders placed above the slide ; expérience, however, has shown that this inconvenience is not to be feared when, as in the present instance, the stability given to the carriage is properly proportioned to the distance from the cylinders to the trunnions—a distance which has been reduced to a minimum. The mounting is provided with the following accessory gear : a loading crâne, with quick-lowering motion ; a loading platform, from which the gun can also be trained, with hand-rail and steps for sighting at minus angles ; elastic buffers which limit the travel of the carriage on the slide in both directions ; an index for the elevation of the gun, with plates showing the direction for turning the cranks ; slieet-iron covers for protecting the délicate parts of the mechanism from dust and splinters. The averao-e initial velocities obtained with the gun have varied between 665 and 707 metres (2182 ft. and 2316 ft.), with a powder charge of 87 kilogrammes (192 lb.), and an armour-piercing shell weighing 164 kilogrammes (362 lb.). 24 - Centimetre (9.449 - In.) Coast - Defence Gun, on Muzzle - Pivoting- Mounting (Fig. 869).—The principal characteristics of this type of material are the following : Length of gun... 19 calibres 19 calibres Weight ,, 14,600 kg. 32,178 lb. ,, mounting ... 27,810 kg. 61,2931b. ,, armour-piercing shell 144 kg. 317 lb. „ prismatic brown powder... 39 kg. 86 lb. Muzzle velocity in service ... 470 m. 1,542 ft. Angles of elevation ... + 30 deg. - 7 deg. + 30 deg. - 7 deg. The breeeh-block is cylindrical, with three threaded parts and three interruptions ; it rests on a bracket which revolves round a vertical hinge-bolt. The obturator con- sists of a composite elastic dise, which unités the advan- tages of the Broadwell ring and those of the usual plastic obturator, while allowing the breech to be worked with great facility. It is placed between the movable head and the front surface of the breeeh-block. Firing is effected with a percussion fuse, by means of a movable boit, or with an electric fuse, when the boit is fittecl with the neces- sary terminais for electric connections. The percussion piece is not in the centre of the vent unless the breech be completely closed, thus doing away with all risk of pré- maturé fire. The mounting consists of the bedplate, and the transom