Since the springs are assembled under an initial load of over 750 pounds, a pull of more than 750 pounds must be exerted upon the spring compressor in assembling them. This can be done by passing a handspike through the loop at the rear end of the compressor and making use of the service of the entire gun squad, or the block and tackle may be used as described above. _To avoid the possibility of injury to the gun squad in compressing or releasing the springs, all should be required to keep arms and bodies away from the front of the spring column during these operations._ CHAPTER VI FRENCH 75 GUN. =Weights and Dimensions.= Weight 1015 lbs. Total Length (about) 107 in. Rifling 24 grooves Twist—right-hand slope, 7 degrees, 1 turn in 25.6 calibers. CARRIAGE. =Weights and Dimensions.= Weight complete 1642 lbs. Weight of gun and carriage complete 2657 lbs. Weight at end of trail, carriage limbered 114 lbs. Diameter of wheels 52.5 in. Length of recoil (about) 45 in. Maximum angle of elevation (338 mils.) 19 degrees Maximum angle of depression (178 mils.) 10 degrees Amount of traverse of gun on carriage (106 mils.) 6 degrees =The gun= is of the built-up type and consists of a forged steel tube which extends from muzzle to breech. A breech hoop is shrunk over the rear of the tube and extends beyond it to provide a breech recess. This recess is threaded with seven threads to take the breechblock. A bronze jacket encircles the central portion of the tube. Inner and outer locking hoops screw to and firmly fasten the tube, hoop and jacket together and prevent them from separating under the stresses of recoil. A muzzle hoop is screwed on the tube at the end of the muzzle. [Illustration: _75 M.M. FIELD GUN_ _MODEL OF 1897_ (_FRENCH_)] [Illustration: 75 M.M. FIELD GUN MODEL OF 1897 (FRENCH)] A recoil lug on the under side of the breech hoop forms a point of attachment between gun and recoil mechanism through the media of a piston rod and coupling key. The rear sight is attached to the rear portion of the breech hoop. On top of the hoop at its rear end are two quadrant seat plugs. The front sight is fixed on top of the rear end of the jacket. A sweeper plate which sweeps and lubricates the roller is secured to the front end of the jacket.