STATIONARY ENGINES.

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bedded on balks of timber, which in some instances form the founda-tion. In these engines a long stroke and low rate of piston speedare adopted, the motion for the pump being as simple as practicableto suit the requirements. The connecting rod is coupled to the pinon the crank, or cast-iron disc when so fitted, by a strap with jibsand key, and the crosshead end has a short fork forged on theconnecting rod, fitted with straps, jibs, and keys. The crank shaftis generally as short as practicable, and is supported by a bearingon the bed plate, and one at the end carried on a pillow block boltedto a box girder secured to the foundations. The fly wheel is madeheavy, and is placed at the middle of the shaft between the twobearings; and at the extreme end a cast-iron crank is fitted, withholes for the pin to vary the stroke of the pump when required.The motion for the pit pump is transmitted by a wooden connectingrod, strapped with wrought iron secured with bolts; the other endof the rod taking a bell crank or arm fitted to the shaft on whichthe bell crank is placed. The latter can be suited to any angle atwhich the pump may require to be placed, as in working the edgecoal in certain localities.

In other arrangements, when the pumping shaft is vertical, themotion for the pump is taken from a crosshead fitted to a Pro-longation of the piston rod, which is continued through the end ofthe cylinder; the crosshead is guided the same as for the main con-necting-rod end, and is connected to the bell crank by wooden rodsstrapped with wrought iron. In such examples the pit pumps arein duplicate, with a bell crank for each, connected together in thesame way; by this means the engine is better balanced, as one setof pump rods is moving upward and the other set downward. Thepillow blocks for the bell cranks are fitted to balks of timber, andthe foundation for the engine is built of brickwork laid on the topof these balks, the brickwork being overlaid with timber for beddingthe engine; the bed plate is secured by long bolts passing down tothe bottom of the foundation. There is no feed pump connectedto these engines, a steam pump being fitted for supplying the boilerswith water.

There are a variety of engines for pumping water of the geareddescription, working plain cranks connected to bell cranks by asingle rod, the bell crank having a jaw cast on it, with a pin fortaking the end of the connecting rod passing through the jaws.This type of engine is generally adopted for low lifts, and is a very