Page:Popular Science Monthly Volume 57.djvu/426

416 The boiler is a very compact form of the upright type, such as is used in fire engines. It is about fourteen inches in diameter and twenty inches high. To increase its strength, it is surrounded with two layers of piano wire. The engine is of the locomotive type, consisting of two



cylinders, the pistons of which are connected with cranks on the end of the shaft, these cranks being set at right angles, so as to prevent catching the engine on the dead center. The direction of rotation is reversed by means of the ordinary link motion. The fuel used is



gasoline, which is carried in the cylindrical tank located under the front of the carriage. The gasoline is vaporized and then, mixed with a proper proportion of air, passes to a burner placed under the boiler. The amount of steam generated is regulated by the amount of gasoline