_Name of Part_ _Where located_ Breech Block On block carrier Vent Bushing Front end of block Block Carrier Hinged to jacket; supports block Block Stop Screwed into front face of carrier Hinge Pin Hinges carrier to jacket Hinge Pin Catch In hinge pin Extractor In breech recess Extractor Lever Mounted on hinge pin Operating Lever Pivoted on block carrier Lever Pivot Pivots lever on block carrier Lever Latch In operating lever Lever Latch Spring In operating lever, lower part Lever Latch Pivot In operating lever, lower part Block Latch In recess in carrier Block Latch Spring Around latch bolt Firing Lock Case In hub of the block carrier Locking Bolt Nut and Pin On firing lock case, rear face of carrier Firing Pin In axle hole, center of firing lock case Firing Pin Spring Around firing pin Firing Spring Sleeve Around firing pin spring Sear In slot in firing lock case Trigger Fork Rear end firing lock case Trigger Shaft On rear end firing lock case Trigger Shaft Detent On trigger shaft Firing Pallet On pallet shank Pallet Shank On recoil lug of gun Firing Handle On firing handle shaft Firing Handle Bracket Attached to right side of cradle Firing Handle Shaft Assembled in bracket, right side of cradle Trip Latch Attached to trip latch plunger Trip Latch Plunger Assembled to firing handle Adjusting Screw Assembled to firing handle bracket Check Nut Assembled in adjusting screw [Illustration: _3 Inch Gun Carriage, Model of 1902._ _Plan_] THE GUN CARRIAGE.