The watch on the left dates from c 1660. It was made by William Crayle (1630-1710) of the Strand, London and shows hours and minutes by a single indicator. The minutes are indicated on an outer scale numbered from 5 to 60. At the end of the hour a new Roman hour-figure appears on the left of the semi-circle. In contrast, the watch on the right shows the time in hours and minutes by separate indicators. Thomas Tompion (1639-1713), one of the finest English clockmakers of the 18th century, made this watch in partnership with Edward Banger in c 1705. The balance wheel is fitted with a balance spring and Tompion type regulator which greatly improved timekeeping.
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