Page:A Dissertation on the Construction of Locks (1785).pdf/28

 the effect, which the cauſe was capable of producing. He ſeems evidently to have conceived the principle, but hath certainly failed in the execution. For, by giving an uniform motion to the tumblers, and preſenting them with a face which tallies exactly with the key, they ſtill partake in a very great degree of the nature of, and the ſecurity of his Lock is thereby rendered in a proportionable degree defective. To make theſe remarks more intelligible, I muſt intreat my readers to ſuppoſe the key, with which the workman is making his way to the bolt, (by the proceſs above deſcribed) to have paſſed the wards, and to be in contact with the moſt prominent of the tumblers. The impreſſion, which the ſlighteſt touch will leave on the key, will direct the application of the file, till ſufficient ſpace is prepared to give it a free paſſage. This being accompliſhed, the key will of courſe bear upon the tumbler, which is moft remote; and