Cock lock, remove fusee spring box and spring, turn crank handle upwards, hold it with right hand and fusee with left, move recoiling portion, with gun horizontal, backwards and forwards, to see that it works freely and that barrel goes home. Weight necessary to move recoiling portion should not exceed 4 lbs. (converted guns 7 lbs.) tested by placing loop of spring balance over knob of crank handle, and pulling to rear when handle is slightly above the horizontal. ASSEMBLING THE GUN. Reverse all the foregoing operations with the exception that the recoiling portions must be replaced before the packing and packing gland. In order to assemble the barrel and breech casings, they will have to be turned upside-down—_i.e._, the filling hole down, and the bottom plate of breech casing uppermost—they should be positioned by the crosshead joint pin. Care must be taken that the ejector tube spring is in position before joining the casings together. When assembling the feed block the longer of the two bottom pawls must always be placed at the front. When assembling the tangent sight, it will be found convenient to place the slide on the stem before attaching the milled head; in this position the pinion is prevented from turning with the pawl when engaging the arms of the slide spring outside the lugs in the pawl. REPLACEMENT OF DEFECTIVE PARTS OF THE LOCK. Should any of the components belonging to the lock become defective they can be replaced from the spare parts, without stripping the lock right down. Proceed as follows:— (i) =Sear.= Fully cock, lift the sear, and let the firing pin engage with the tumbler and trigger; with the lock on the bench, left side up, drive out the sear axis pin, and remove the sear with its spring. (ii) =Tumbler.= Fully cock, thus engaging the firing pin with the sear; drive out the axis pin of tumbler, pull the trigger slightly, and lift out the tumbler. NOTE.—Care should be taken not to allow the screwed head to lift the sear when once the tumbler has been removed. (iii) =Trigger, Lock Spring or Extractor Levers.= Release the lock spring, drive out the lock spring axis pin, remove the keeper bracket, extractor levers and lock spring; if the trigger is defective, drive out the trigger axis pin and remove the trigger. (iv) =Firing Pin.= Proceed as for (iii), but do not remove the trigger. Remove the tumbler axis pin and tumbler, raise the sear, push the screwed head out of its way, and the firing pin will drop out. (v) =Gib, Gib Spring, or Extractor Spring.=