It came from a family in Leicester who believed it had been bought at auction by their grandfather at a country house sale sometime from the 1920s-30s.

The appeal was all in the makers’ name: the movement is signed for the well-known partnership of Thomas Mudge and William Dutton and numbered 721.

It was dated by the hallmarked case and serial number to c.1766 – a year after Mudge and Dutton (both apprentices of George Graham) became partners at 148 Fleet Street and the publication of Mudge’s influential book Thoughts on the Means of Improving Watches, Particularly those for Use at Sea.

The movement features his lever escapement – perhaps the greatest single improvement ever applied to pocket watches. It is contained in a rococo pierced foliate case and an outer case featuring an engraved crest of a leopard’s head above a crown.

Bids opened at the low estimate of £2000 with trade interest on the book. The battle was joined by three phone lines plus two collectors and a BADA dealer before switching to online bidding. It was hammered down to a watch dealer at £5500.