STATIONÄR Y ENGINES.

199

secured to the cast-iron beams upon which the bell-crank pillowblocks and air pump and condenser are fitted. The air pump is ofthe ordinary kind, fitted with india-rubber valves for bücket, head,and foot valves. The condenser is a separate vessel placed alongside

Fig. 126.—Direct-action Compound Pumping Engine.

of the air pump, the waste-steam pipe coming in at the top, andfitted with a packed gland. The valve gear for these engines is ofthe usual description, with cataract pumps for regulating the numberof strokes. Although the machinery in these engines is rather com-plicated, yet when economy in fuel and great regularity in working