The Works Of Messrs. Schneider And Co.

24-CENTIMETRE GUN AND DISAPPEARING CARRIAGE. 275 top part of which constitutes horizontal slides, in which are fittecl friction rollers of the type previously described, to facilitate the travel of the cradle. The slide is continuée! at its lower part by a cylindrical sleeve made of plates, inside which is the hydraulic cylinder used for raising the mounting and regulating the disappearing action. The vertical motion of the sleeve is guided by a set of horizontal rollers, mounted on the vertical pivot of the movable platform. The movable platform carries the horizontal shield, and also the lateral training mechanism. It is circular, and its lower face bears on a series of friction halls; it is fitted with a vertical ring, to which are attachée! the centring rollers of the sleeve. The platform is guided in its rotaiy motion by a second series of rollers, the vertical axes of which are fitted to the cylinder that forms part of tlie cast-iron bedplate runuing up and clown. The cast-iron counterweight con- sista of a large-diameter ring, guided in its action by a set of horizontal rollers on vertical guides ; at a given moment, it can rest completely on a bedplate bolted on the lower part of the movable sleeve, and then the weight of the wliole arrangement is sufficient to act against the resisting power of the accumulator. The counterweight can be raised independently of the sleeve, by three piunger pistons contained in vertical hydraulic cylinders, worked simul- taneously by the forcing pump. These hydraulic cylinders are embedded in the foundation. The required elevation is given the gun by a hand- wheel placed in the rear of the left-hand cheek of the slide. The transmission contains a set of square-toothed wheels, an endless screw and differential gearing, working a square pinion that engages the toothed sector fitted on 24-Centimetre Schneider-Canet Gun and Disappearing Carriage. which carries the whole of the system ; this bedplate contains a ring that bears on the foundation, and through which run the foundation bolts. Its top part is made with a groove that forms a path for the friction halls. It is strengthened by a series of radiating ribs. Its lower part ends in a vertical cylinder, which rests direct against the cemented wall of the pit, and carries the axles of the | guiding rollers of the movable platform. The pit itself [ communicates with a large-sized room that contains part of the hydraulic mechanism and the counterweight. The room is joined to the battery communications through an underground passage. The fixed piunger that works in the hydraulic cylinder is drilled for its whole length, and parallel with its centre line ; the conduit thus established communicates through a tube fitted with regu- I lating valves, with a hydraulic accumulator, designed for [ storing a power slightly above that required for counter- | balancing the weight of the movable mounting during tlie left side of the gun. Lateral training is obtained with the help of a mechanism similar to that described further on for the 27-centimetre (10.630-in.) gun mountings. The plate chain that surrounds part of the circumference of the movable platform, is driven by a spurwheel keyed on a vertical shaft, which goes through a ehest containing the driving mechanism. The gun can be trained direct from the platform with tlie help of a crank, or through a chain transmission worked by a gunner standing on the shield. When the gun is in battery, the cast-iron counterweight rests on the lower collar. On firing, when the carriae'e recoils, it travels on the slide rollers, and the recoil cylinder acts in the same way as that for the types described above. When the recoil is spent, the valve that establishes com- munication between the recoil cylinder and the recupe- rator closes and maintains the gun run in. At the same time, the valve which establishes a communication between