The Works Of Messrs. Schneider And Co.

BARBETTE TURRETS. 245 engage in a part of tbe slides tliat are turned over at an angle, and bring the ammunition tray into the required position for loading or unloading. A latch-bolt allows of the apparatus being held fast at both extreme positions. The projectiles and cartridges are brought to the lower staging in a truck, on a line fixed to the deck beams. Barbette Turret for 32-Centimetre (12.598-In.) Gun (Figs. 808 to 813, Plate CXXXIX.).—Turrets of this type have been built, among other ships, for the “ Pelayo,” of the Spanish Navy. The gun is held by longues and grooves in a carriage, which travels on a slide formed of two beams pivoting round horizontal trunnions, attachée! forward to the floor of the platform; between the beams are the recoil cylinders and the Intermediate compensator, the system being complétée! by damps and buffers. The recoil piston-rods are fitted to two lugs in the front of the carriage ; in the rear is the intermediate piston-rod. The intermediate piston is made with a series of small vents, and the recoil cylinders are provided with regiets of varied section, calculatecl to maintain a practically constant effort during the period of recoil. When the gun is fired, the carriage.in recoiling moves the piston-rods in the cylinders ; this causes the liquid to flow through the rectangular vents, and to lift the valves until it reaches the interme- diate cylinder. When the recoil is complété, the valves fall back on their seats, and the gun remains run in. To run it out for firing anew, water under pressure is delivered through a special pipe to another cylinder, and the front of the intermediate cylinder is connectée! with the exhaust. In conducting operations inversely, the gun would be run in. The gun, carriage, and mounting rest on the movable platform, which consists of two beams joined by a circular built-up girder. The framing of the turret is stiffened by radiating stays. A staging of plates and angles in front, carries the hydraulic cylinder for elevating the gun. The wliole of the platform rests, with the interposition of a series of rollers, on a ring bolted to the deck. The central ammunition tube is provided at the top with a ring, which insures the accurate guiding of the system. Below the armoured deck is fixed a lateral training circular piece, which surmounts the guiding socket fixed to the frame ' that carries the hydraulic cylinders. Inside the tube are the guides, hydraulic cylinders, and gear for the working of the hoist. The gun is elevated by means of an hydraulic cylinder, the piston-rod of which, acting on the underside of the carriage, causes the latter to oscillate l'ound its trunnions. Lateral training is obtainecl by con- nectée! hydraulic cylinders, placed underneath the armoured deck ; the piston-lieads of these carry each a pulley round which passes a plate - chain that surrounds tbe rack fixed to the tube. The. two ends of the chain being fixed to the hydraulic cylinders, it is sufficient, in order to train the gun, to put one of these cylinders in connection with the accumulator and the other with the exhaust. The dis- tribution valves are worked by a small hand-wheel within easy reach of the gunner. For loading, the gun has to be elevated to its maximum angle. Ammunition is raised by means of a drum carrier with three conipartments ; the working is controlled by the hydraulic cylinders and gear a hydraulic automatic brake Controls the delivery from the' hoist at the top staging. The carrier is mounted on a roller truck, which by travelling in the slides is brought I to the rear of the breech ; it is free to turn round its axle, so as to place successively each one of its compartments opposite the bore. To the rear is the telescope rammer, with the Help of which each part forming the charge is driven home. Manœuvres on the lower staging are carried on with the help of hydraulic crânes and tackle, made to travel on a circular line fitted to the deck-beams. Barbette Turret for 340-Millimetre (13.386-In.) Gun. -—Turrets of tins type (Figs. 814 to 818, Plate CXL., and Figs. 819 and 820), have been built for battleships. They comprise the carriage and its slide, the turret, the elevating and lateral mechanisms and the hoist. The gun is invariably joined to the movable carriage which constitutes the mounting proper, by a tongued and grooved ring which surrounds the breech-end. The'carriage rests on shoes forming damps on the slide- I paths of the main beams of the mounting, which ' consists of two vertical parallel cheeks strongly stayed i together. Recoil is governed by two hydraulic cylinders, which aet at the same time as controllers in running I out the gun, which can be effeeted at all angles by i introducing water under pressure to the rear of the I recoil pistons. The whole of the system rests on the ! movable platform, to which is fitted a vertical tube formed of plates, as illustrated by Figs. 814 and 815 ; ammunition is suppliée! through this tube. It extends down to the magazines placed under the armoured deck, and is guided at both ends ; as will be seen from Figs. 815 and 818, it is used to rotate the turret, through the hydraulic cylinders and chain on a lower deck. The dis- tribution ehest for water under pressure is placed at the i level of the lower staging. The mounting and all its [ mechanism are coinpletely protected by the fixed armour, and also by a light structure which turns with the plat- form. In the the rear is the gunner’s stage, surmounted hy a shield. For elevating the gun, the slide pivots round its trunnions in front, the tmnnion plates being fixed to the movable platform ; the latter rests, with the interposition of a ring of rollers, on the fixed circular path bolted to the upper deck. Elevation is obtained by means of a hydraulic cylinder, the piston of which, placed under the slide, causes the whole of the mounting- to rise or fall ; a valve-chest, with i a lever within easy reach of the gunner, is suitably arrangée! I for obtaining the required actions. The lateral training mechanism consists of a toothed ring fixed on the tube (see Fig. 817), and surrounded on half its cireumference by a I plate-chain. Pulleys are mounted on the ends of the piston-rods of the two hydraulic parallel cylinders, and around these pulleys the chain passes. When one of the cylinders is open to the pressure, the other is free to the