and the external fittings are added, when the cranes again seize the engine and convey it to the paint shop. Meanwhile the tender has been constructed in another shop. It is now coupled to the engine, the two are painted, and, after receiving a trial, are ready for service. The usual time required in the erecting shop for building an engine is about four weeks, while the shortest time in which any engine has been built in this shop in the ordinary way of business is fourteen days. As an illustration, however, of what could be accomplished at these works in case of emergency, it may be mentioned that some time ago, as an experiment, the erection of an engine was commenced at six a.m. on a Monday, and at one o'clock on the following Wednesday, or within a space of twenty-five-and-a-half working hours from the time the frame plates were selected and laid down, the engine was finished, and in steam, and ready to work a train.
In the fitting shop, which, to the unaccustomed eye, presents a most bewildering appearance, with its endless ramification of pulleys, shafting, revolving wheels, and machinery of every description, all kinds of operations connected with the making of the various parts of an engine may be seen in progress. Here are turning lathes, planing, shaping, slotting, boring, and drilling machines. Here are made the cylinders, the pistons, the valves, connecting rods, injectors, axle-boxes, and a hundred other small fittings and castings, all these being adjusted to standard gauges suitable to the various classes of engines, without respect to the individual engine for which they may happen to be used. Thus, to a great extent, the interchangeability of parts is secured, so much so, that four of the standard classes of
