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Inventory no. 52905 - Former Display Label

The Tic-Tac Escapement

Of considerable rarity, the Tic-Tac escapement shown here, seems to have been a product of the period of intensive experiment by London makers in controling the pendulum. The earliest example of its use so far known is by Joseph Knibb in the split-second clock produced by him for James Gregory in 1673. A modification of the anchor escapement, it has one arm slightly longer than the other, but embraces only two or three teeth of the escape wheel, instead of the eight or more covered by the anchor. Examples of its use in clocks by Thomas Tompion c. 1675, by Samual Watson c. 1695, as well as the John Knibb shown here of c. 1680 are known. However, it seems never to have been in widespread use, perhaps because it offered no real advantages over the horizontal verge escapement for controlling spring-driven pendulum clocks.

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