Page:Popular Science Monthly Volume 12.djvu/157

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THE GROWTH OF THE STEAM-ENGINE.

economy in working steam in this manner, it seems gradually displacing all other forms of engine.

PSM V12 D157 Hornblower compound engine 1781.jpg
Fig. 19.—Hornblower's Compound Engine, 1781.

44. An example of this form of pumping-engine, and one which is a favorite with many engineers, is the beam and crank engine (Fig. 20),

PSM V12 D157 Compound pumping engine 1860.jpg
Fig. 20.—Compound Pumping-Engine, 1800.

C D, E F, with double cylinder, A, B, working the "combined bucket and plunger," or double-acting pump, J. In its cylinders steam