Page:Popular Science Monthly Volume 12.djvu/158

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THE POPULAR SCIENCE MONTHLY.

is usually expanded from four to eight times. The Leavitt compound engseine is shown in Fig. 21.

PSM V12 D158 Leavitt pumping engine.jpg
Fig. 21.—Leavitt's Pumping-Engine, 1875.

In this engine the lower ends, A, B, of the two cylinders are brought close together under the centre of the beam, thus shortening

PSM V12 D158 Worthington compound pumping engine 1870.jpg
Fig. 22.—The Worthington Compound Pumping-Engine, 1870.