[174] & [175]. Two forms of crank pin eccentrics; sometimes used to drive the slide valve instead of the ordinary sheave and strap, as [No. 183].
[176]. Crank pin set in a boss formed on the driving wheel.
[177]. Double rod crank.
[178], [179], & [181]. Hand cranks. These should always be fitted with a loose ferrule of wood for the hand if possible, as much power is lost by the slipping of the hand to change its grip as the crank revolves.
[180]. Solid three-throw crank shaft, turned out of a solid forging.
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[182]. Built crank. Several modifications of this are in use for large marine shafts.
[183]. Solid sheave eccentric.