763,618. Ordnance, elevating and training gear. BAUER, R. E. Dec. 11, 1953 [Jan. 12, 1953], No. 34546/53. Class 92. [Also in Group XXIX] In a combat vehicle hydraulic power transmission system (see Group XXIX) the elevation of a cannon 91 is effected by a hydraulic motor 6 under the control of a reversing valve 41, and the traverse of the cannon is effected by a radial-cylinder motor 5 under the control of. a valve 40. Valves 40, 41 are controlled manually either from a gunner's or a commander's control mechanism. Valves 41, 40 carry rollers 258, 259 engaged in slots 252 in blades 226, 224 which are pivoted on the ends of a stub shaft 228 which is mounted in slots 225 of a housing. The stub shaft is normally urged by a spring 234 to the position shown in which rollers 260, 261 of the gunner's control mechanism are engaged in the slots 252. The gunner's control mechanism comprises handles 276 secured to a shaft 274, rotation of the handles about the axis of the shaft actuates, through a suitable linkage, the roller 261 to pivot the blade 224 and control the position of the valve 41. Rotation of the handles and the shaft 274 about an axis perpendicular to the shaft actuates the roller 260 thus pivoting the blade 226 and controlling the position of the valve 40. The commander's control is generally similar to the gunner's and when it is to be operative a switch 198 is closed, resulting in the actuation of a piston 188 which moves the stub shaft 228 to the other end of the slots 225, disengaging the rollers 260, 261 from the slots 252, and bring- ing rollers 264, 265 of the commander's control mechanism within slots 250 so that the valves 40, 41 are under the control of the commander's mechanism. Provision is made for traverse and elevation of the cannon manually.