STATIONARY ENGXNES.

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lever for the eccentric rod for the starting handle. These leversshould be made very strong and well feathered, and rriay be castalong with the shaft, at least those for the stoup and balanceweight, but the eccentric lever should be made a separate castingfor adjustment. As the strain is light a cast-iron shaft and leversmay be adopted, when the weigh shaft is placed under the floor ofthe engine house out of sight; but a preference ought to be givento wrought iron in all valvular arrangements, as the material isbetter adapted for any sudden strain, even although balance valvesare adopted.

The valves are actuated bv means of an eccentric and rod. The

Fig. 158.—Eccentric and Rod.

A, Eccentric sheave. b, Eccentric rod and strap. c, Gab end.

eccentric sheave is so arranged that it can be put on and taken offthe main crank shaft without disturbing any other detail, and issecured on the shaft with a key, as these engines only require tobe worked in one way. The eccentric rod is of wrought iron; one-half of the strap is forged on with suitable lugs, and the other halfhas lugs forged on for bolting the hoop together, with a single boltand nut for each lug. The rubbing surfaces are of brass, rivettedto the strap, and then accurately turned to suit the sheave. Thelugs on the strap do not fit closely together, so as to adjust at anytime the rubbing surface. Suitable mechanism for lifting theeccentric out of gear when starting the engine should be arranged.This may be worked in a variety of ways; with hand levers, orwith a foot lever and rod attachment, which the attendant can press