=The firing mechanism= like that of the American 75 is located on the left side of the gun instead of the right side as on the 3” and the French 75. The gun can be fired when it is within 2 inches of the “in battery” position, which increases the possible speed of firing. CHAPTER IX THE 4.7” RIFLE, MODEL 1906. GUN. Weights and Dimensions. Weight 2,688 lb. Caliber 4.7 in. Total length 134.92 in. Length of bore 129.42 in. Length of rifling 111.9 in. Number of grooves 42 Twist Right hand. Weight of proj. based fuse 60 lb. Weight of proj. point fuse 45 lb. Weight of powder charge 95 oz. Muzzle velocity, 60 lb. proj. 1,700 ft. per second Muzzle velocity, 45 lb. proj. 2,050 ft. per second Maximum range 11,000 meters THE CARRIAGE. Weight of carriage complete 5,320 pounds Weight of carriage and gun complete 8,068 pounds Maximum elevation 15 degrees Maximum depression 5 degrees Maximum traverse 140 mils. =The gun= is built up and consists of a tube, jacket, locking hoop and clip. The jacket covers the rear half of the tube and projects beyond the tube at the rear to form the breech recess. The jacket also has a recoil lug on the under side for connecting the recoil cylinder. The clip is a short hoop near the muzzle and has guides formed on it to guide the gun in the cradle on recoil. The jacket also has guides formed on it. The length of the gun is approximately 11 feet. [Illustration: 4.7” Rifle] =The breechblock= is of the interrupted screw type having four threaded and four plain sectors. It is operated by a handle which swings from left to right turning and withdrawing the breech with one motion. An extractor is fitted for throwing out the shell case when the breech is opened after firing. The firing mechanism is of the type known as a continuous pull mechanism, that is, the mechanism is cocked and fired by the pull on the lanyard or by downward pressure on the firing handle located at the right side of the breech. The recoil system is of the hydro-spring type. The two parallel steel tubes (the spring cylinders) are fitted into a frame surmounted by heavy steel rails which form the gun slides thus forming the cradle. The recoil cylinder is fitted between these two. The recoil and counter-recoil piston rods are attached to the gun lug and recoil with the gun, while the spring cylinders and recoil cylinder remain stationary.