USING REVERSE-MOTION AS A BRAKE.
Numerous attempts have been made to utilize the reversed engine as a brake for stopping the train, and even by this means to save some of the power lost in stopping. Chatelier, a French engineer, experimented for many years on this mechanical problem. He injected a jet of water into the exhaust-pipe, which supplied low-tension steam to the cylinder, instead of hot gas or air coming through the smoke-box. This was pumped back into the boiler on the return stroke. Thus the act of stopping a train was used to compress a quantity of steam, converting the work of stopping into heat, which was forced into the boiler and retained to aid in getting the train into speed again. Modifications of this idea produce the car-starters that pass so frequently through our Patent Office.
As a means of conserving mechanical energy, the Chatelier brake was not a success; but, in the absence of better power brakes, it met with some applications in Europe. Some of our mountain railroads use it, under the name of the water-brake, as an auxiliary to the automatic brake.