Page:A Dissertation on the Construction of Locks (1785).pdf/18

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require. The ſecurity of Locks therefore, and their comparative excellence, are determinable by the number, variety, and diſpoſition of the wards, or other impediments inſerted in the paſſage by which the lever, or key is conveyed to the bolt. If theſe outworks do not ſecure the bolt from the intruſion, and application of every inſtrument but its proper key, the Lock is inadequate to its intended purpoſe; and however intricate or difficult, the paſſage to the bolt may be rendered by a ſkilful and judicious diſpoſition of the wards; yet, if any acceſs to the bolt is practicable by a workman of equal ſkill with its maker, the Lock is defective in the main point of excellence, which is effectual ſecurity; and is entitled to no higher claim than comparative merit.

The Conſtruction of Locks, is a ſubject on which many ingenious mechanics have employed their thoughts; and the art hath received many, and great improvements from

their