1086

THEORY AND PRACTICE OP ENGINEERING.

Book II.

is given to the pulley i and j and band A, which work, the saw b, and which cut off thehead of a pile in less than a minute.

Fig. 1657.

STEAM PILE-DRIVING MACH1NB.

This machine has been very successfully employed on the railways in America , where thegauge was 6 feet from centre to centre; two piles were driven at the same time, with aram weighing 16 cwt. ; the number of men employed consisted of an engine tender, oneman for throwing each apparatus in and out of gear, and one man to attend to each pile,making all together five men for driving two piles, which is about half the number of menrequired to drive two piles by the ordinary crab engines. By the machine the ram waslifted four or five times in a minute, and the cost of the whole engine and apparatus wasabout 7004