MARINE ENGINES.

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tandem form, having generally the high-pressure and low-pressurecylinders in line, but occasionally alongside, and always communi-cating their power to one crank. 3d. The three-cylinder intermed-

a, High-pressure cylinder.b B, Low-pressure cylin-ders.

c c, Piston rods.d, Crosshead for pistonrods.

es, Side rods connectingbottom and top cross-heads.

F, Crosshead for connecting rod.

G, Connecting rod.

h h, Frame and guides for crosshead.

l, Crank.

k k, Main frame.

ll, Columns supporting main frame.

m, Condenser.

N, Lever for working air-pump.

o, Air-pump.

p, Feed pumps, &c.

Q, Kingston valve.

Fig. 378 b.— Three-cylinder Compound Steeple Engine for the Paddle.

iate receiver compound engine with one high- and two low-pressurecylinders, the steam passing from the high-pressure cylinder into thereceiver, and thence into the two low-pressure cylinders respectively.

The arrangement shown by Fig. 378 B is of the three-cylinderdass. The steeple form of engine is adopted; the three cylindersof each engine being bolted to each other and to the keelsons.