The Works Of Messrs. Schneider And Co.

210 MESSES. SCHNEIDER AND CO.’S WORKS. ■close the breech, the crank is turned round inversely. A special latch, governed by a spring, alternately joins the support to the breech-block and to the gun. Figs. 703 to 706, Plate CXXI., show the breech closed, the block unscrewed, withdrawn, and the breech opened. Figs. 707 to 710 illustrate another type of Schneider- Canet breech-blocks for large-calibre guns ; the general arrangement is similar to that just described ; but besides the endless screw and the rack gear for turning the breech-block, there is a separate bolt which forms a hinge for swinging it to the side. A set of gearing Schneider-Canet Breech-Mechanism for Large-Calibre Guns. Figs. 707 to 710. placed under the bracket puts the endless screw in motion, and insures the opening and closing of the breech. The inechanism for percussion firing and the safety device, are similar to the corresponding parts of the preceding breech-block. In another modification, the continuous action of a crank also produces the opening and closing of the breech. The opening action consiste of turning, withdrawing, and swinging the breech-block to the side by means of pinions .and racks ; but in this type all the toothed wheels are «overed, which insures greater safety in service. The breech-block has four threaded parts and tour | ceases to give place to another. interruptions ; it is fitted at the back with a toothed sector for turning, and with a longitudinal rack for withdrawing, the block. It is guicled in a bracket provided with a closing disc, and which can turn round a hinge supported on steel lugs. The hinge bolt is fitted with two pinions of different diameter ; one of these engages a double-toothed rack that can slide borizontally in a groove on the rear end of the gun to effect the turning ; the second set of teeth is arranged to engage the toothed sector fitted to the breech-block ; the other pinion works the longitudinal rack when the turning is completed, and withdraws the breech. The action of the crank is transferred to the two pinions through an endless screw and a suitably-geared wheel. A double- latch bolt fitted in the bracket fixes it to the breech, and the block to the bracket, so that the three motions of unscrewing, withdrawal, and swinging to the side, always follow in the required succession. A small cam on the hinge bolt fixes the unscrewing rack during the withdrawal of the breech-block and its swinging to the side. The teeth of the pinions and rack are so shaped that the breech-block is never abandoned when one action