with each other, the engine will run towards one side or the other of the track, according to the inclination of the axles. It sometimes happens that the bolts which hold up the wedges in the jaws are broken. When this occurs the wedge drops down, and of course the box has so much lost motion that it soon manifests itself in the working of the engine. These bolts, and also those which hold up the clamps on the frames at the bottom of the jaws, should be examined when the engine is inspected, so as to be sure they are in good condition. The bolts and nuts about both the engine and tender trucks should be watched to see that none are lost or work loose. The engine and tender should occasionally be lifted up from the centre plates of the truck, and the latter be lubricated with tallow. It often happens that these become dry, so that they are difficult to turn when the weight rests on them, and therefore they will not adjust themselves easily to the curves of the track. QUESTION 469. _What other parts of a locomotive should be examined before starting?_ _Answer._ It should be certain that the brakes on the tender are in good working condition, that is, that the bolts, nuts and keys are all secure, the levers, rods and chains properly connected, and the shoes fastened and not too much worn. If either an atmospheric or vacuum brake is used, it should be tested before starting, to see that the pump or ejector is in good working condition. It is also well to apply the brakes to the train before starting, so as to see whether the connections are in good condition and properly connected. It is always best for the locomotive runner to examine the connections of the brake hose through the whole train himself, to be sure that they are properly made. The inside of the water-tank should also be examined occasionally, to see whether it is clean, and if not it should be thoroughly washed out. The man-hole should always be covered before starting, in order to prevent cinders and coal from falling in, which are liable to obstruct the pump valves. It is hardly necessary to say that it must always be certain before starting that there is enough water in the tank to feed the boiler until the next point is reached at which a supply can be obtained. The sand-box must also be filled, the bell rope in good condition, and if running at night the reflector of the head-light must be polished and the lamp supplied with oil and the wick trimmed so as to burn brilliantly. The locomotive runner must also see that the proper signals are displayed in front of his engine. QUESTION 470. _What tools, etc., should every locomotive runner on the road carry?_