FORCES TOO GREAT OR TOO DELICATE.

35

CHAP. VII.

EXERTING FORCES TOO GREAT FOR HUMAN POWER,AND EXECUTING OPERATIONS TOO DELICATE FORHUMAN TOUCH.

(40.) It requires some skill and a considerableapparatus to enable many men to exert their wholeforce at a given point, and when this number amountsto hundreds or to thousands, additional difficultiespresent themselves. If ten thousand men werehired to act simultaneously, it would be exceed-ingly difficult to discover whether each exerted hiswhole force, and consequently, ,to he assured thateach man did the duty for which he was paid. Andif still larger bodies of men or animals were neces-sary, not only would the difficulty of directing thembecome greater, but the expense would increase fromthe necessity of transporting food for their subsist-ence.

The difficulty of enabling a large number of mento exert their force at the same instant of time hasbeen almost obviated by the use of sound. Thewhistle of the boatswain occasionally performs thisservice; and in removing, by manual force, the vastmass of granite, weighing above 1400 tons, on whichthe equestrian figure of Peter the Great is placed atSt. Petersburgh, a drummer was always stationed onits summit to give the signal for the united efforts ofthe workmen.

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