“In 20 years I have never seen anything quite like it,” says auctioneer Richard Bromell of Sherborne’s Charterhouse. “It has a central dial for Greenwich which is surrounded by 11 smaller dials telling the time in the various countries. Having originally been presented to a Victorian relative [of the vendors] who built railways for a living, he would have been able to keep track of time with all his business interests.”

Of the 12 cities listed, included are Port Natal, Sidney (sic), Madras, New York, Sevastopol, Calcutta, St Petersburg and Paris. It also strikes the quarter hours on eight bells driven by a triple fusee movement.

Its Long Street Salerooms appearance on December 10 is thought to be the first time that the 2ft 3 1/2in (70cm) high clock had been on the open market since it was presented to an ancestor of the vendors nearly 150 years ago.

With a bank of telephone bidders, five-figure commission bids from collectors in the South West and the US, bidding rose quickly to £20,000 and then stopped at £21,000, when the clock went to a UK dealer on the telephone.