Sussex Saleroom: 14th, 15th, Thursday 16th May 2019
A HISTORICALLY INTERESTING BRASS-BOUND ROSEWOOD TWO-DAY MARINE CHRONOMETER WITH AUXILLARY COMPENSATION
By John Poole, London, No. 1086, circa 1844, used during the 1874 Transit of Venus Expedition
The two-tier case, lacking top lid, with glazed observation cover, and with circular ivory roundel engraved with Admirality arrow and POOLE 1086 TWO DAYS, brass gimbals and locking lever, the circular silvered 3 3/4in. dial signed John Poole, 57 Fenchurch Street, London 1086, with blued steel spade hands and seconds subsidiary at the VI and power reserve at the XII, the movement with Admiralty arrow, bi-metallic compensated balance with Poole's auxillary, blued steel helical spring and diamond endstone, Earnshaw spring detent escapement
16cm wide, (one key).
This chronometer was purchased by the Admiralty on 14 August 1844. It served on HMS Cygnet, HMS Lightning, HMS Shearwater, HMS Sylvia, HMS City of London and HMS Caroline. It spent periods at Devonport, Portsmouth, the Cape Observatory and Hong Kong. It saw service in WWI, left wartime service in 1916 and was sold in 1919.
Selected for service with HMS Shearwater, this took it to Rodriguez Island, arriving on 18 August 1874, for the observations for the Transit of Venus. The expedition was led by Commander J. W. L. Wharton, RN. One of three chronometers taken on the expedition, it is recorded that Captain Wharton preferred this instrument over the others for his observation work.
Account of Observations of the Transit of Venus, 1874, edited by Sir George Airy, KCB, Astronomer Royal, London 1881, which details this chronometer.
Astronomical Observations Made Under the Direction of G. B. Airy 1841-47, details Poole No. 1086, which was rated for purchase by the Board of Admiralty, at the Royal Observatory, Greenwich in 1844.
Sold Bonhams, London, 28 June 2011, lot 137.