All About Engines

The Modern Reciprocating Engine *35 horizontal engines should be installed in some cases, the general tendency is towards high-speed vertical engines, totally enclosed, and provided with an arrangement whereby oil is pumped regularly at constant pressure between the rubbing surfaces. High speed gives the steadiest running, and is especially desirable in driving dynamos ; total enclosure keeps out dirt, and especially grit, which is liable to get between the rubbing surfaces and cause wear ; and forced lubrication, together with enclosure, renders the engine fool-proof. As an example of such a modern engine, we shall describe that made by Messrs. Beiliss and Morcom. The makers call this a quick-revolution, not a high-speed engine, for while it makes from 200 to 650 revolutions a minute, according to size, the shortness of the stroke enables this to be attained without requiring a high-piston speed. The reci- procating parts, therefore, are subject to smaller changes of motion than would be the case in an engine making the same number of revolutions a minute and proportioned as in horizontal engines. They are made with one, two, or three cylinders, and may be used either condensing or exhausting to the atmosphere. The first engine of this type—and the first engine to have forced lubrication—was made in 1890, and is still running for ten or twelve hours a day in the makers’ works at Birmingham. It gives 20 horse- power at 625 revolutions a minute, and in the twenty- six years it has been at work it must have made 3,000 million revolutions.