Oval verge escapement watch, c 1630.

Watch made by Richard Jackson. Jackson was given the freedom of the Clockmakers' Company in 1632. Until the 15th century, clocks were powered by falling weights, and so could not be moved about. The use of a coiled spring to drive the hands meant that portable clocks and watches could be made, but they were not very accurate. Jackson's verge escapement watch is an example of such a watch.