KEYING SIDE RODS.
When it is necessary for an engineer to key up side rods, he should select a place where the track is straight, and as even as possible. Then he should put the cranks on the center, and take care that he can move the connections laterally after the job is done. If he now moves the engine so that the cranks are on the other center, and finds that the rod connections can still be moved, that side is all right. If the other side be treated in a similar manner, his rods are not likely to give trouble. With a worn-out engine and rough road-bed, it is a difficult matter to preserve the true mean between loose and tight side-rod connections. But, in a case of doubt, the loose side is the safe side. Yet most engineers are inclined to err on the side of danger, for they will generally tighten up the rods to prevent them from rattling. On a Western road, where solid-ended brasses were adopted, it was often amusing to hear the engineers protesting against the noise the side rods made when the brasses began to get worn. They would rattle from one end of the division to the other; but they would not break pins, or fracture themselves, and tear the cab to pieces, or ditch a train, as happens so often from other rods being keyed to prevent noise. Sprung crank-pins and broken side rods are very often the result of injudicious keying.