The Locomotive Of Today

112 The Engine: Rever sing Lever, Rod and Serew. grades of expansion. The trigger may be as shown, on the back of the lever, or it may be placecl upon the front, a spring being provided to keep the catch down in its notch, as other- wise it would be liable to work up when the engine is running' and allow the lever to be thrown violently to the front or back of its travel, according to the position of the valve gear, which might have unpleasant results. The spring may be flat, situated between the trigger and handle as shown, or it may be coiled and attached to the bottom of the catch rod, with one end secured to a hook in the lever; another mode of attachment is by a bracket Htted above the catch, the catch rod passing through it, and the coiled spring being on the rod between the catch and bracket. A boss is provided at a point in the length of the lever and having a pinhole for the attach- ment of the forked end of the reversing rod, which at its other end is coupled to the arm of the reversing shaft. A bracket is fixed to the side of the plate for the driver to place his foot upon and so inerease his power to pull the lever over. In the above lever the reversing rod is coupled to an arm projecting up from the reversing shaft, but in cases where these arms are carried downwards, the lever is then made mueh longer and pivotted at or near its centre, the lower halt being carried down below the footplate and the rod coupled to it there. A modification of the lever, fitted with a screw at the top instead of the handle is shown at B. The lever has a forked end at the top and is fitted with a pair of sliding blocks, which work upon projecting pins upon the nut through which the- screw revolves; it is pivotted at its centre, and being usually coupled to an arm projecting up from the reversing shaft, the top of the lever stands over to the back when the engine is in forward, and to the front in backward gear. The pivot may be, as shown, fixed to the side of the tank, or in the case of tender engines, which have no tanks, it is fixed to a separate plate attached to the frame beneath it. The screw is cut with a treble thread so that the movement of the nut, and with it the lever, may be as quick as possible; it is carried in brackets. at each end, and fitted with a wheel by which the driver may operate it. The wheel has attached to it a circular notehed plate and, upon the bracket carrying the bearing for the- screw, a catch is provided which can be dropped into the corresponding notch of the plate, thus securing the screw in any required position, as the thrust upon the nut when the engine is running is liable to cause the screw to revolve and put the motion into full gear. Above the screw and nut a. guard or cover is fixed, having at its top a slot of a length