2024 January Meeting

In 1807, the chronometer maker William Hardy persuaded the Board of Longitude to run a trial, at the Royal Observatory, of a regulator escapement that he had recently invented and fitted to an existing clock, by another maker. Its performance was such. that the Astronomer Royal ordered a bespoke clock from Hardy for use with the new Mural Circle that was being made for the Observatory by Edward Troughton.

Hardy’s clock is one of the most important that the Observatory ever owned. It served as a transit clock from the time of its arrival until it was retired from active service in 1954. During the period 1823 to 1871 it was also the de facto sidereal standard – the clock by which all the Observatory’s other clocks were set. During its life, it has undergone numerous and significant alterations. It can be seen today in the same position that it has occupied since the end of 1850.

In total, Hardy made at least 18 regulators, and possibly as many as 23 or more. Amongst those who originally owned them were wealthy individuals rich enough to have an observatory of their own. Others were supplied for government and privately funded institutions, including two clocks for the American Coastal Survey and three to the Russian Government. A recent survey of 12 of Hardy’s surviving clocks has shown that only two of them may once have been identical. The talk will end with a review of these 12, with some of the differences between them will being highlighted.