Marine chronometer by Poole, London, c. 1840

Dealer description — Howard Walwyn

A fine mid-19th century brass-bound rosewood 8-day marine chronometer by this famous chronometer and instrument maker. The three-tier rosewood case is neatly bound in brass, with reinforced corners, flush brass straps, and a vacant brass cartouche to the top lid. The front of the middle tier has a brass push button with a twelve-point star escutcheon above a rectangular ivory name plaque, and the sides are fitted with two substantial brass carrying handles. The interior is arranged to house the chronometer bowl within its gimbal ring, with the lid opening on brass hinges. The circular silvered dial is engraved with Roman numerals and an outer minute track, and is signed Poole London and numbered 882 . There is a subsidiary power reserve at XII, marked WIND / UP , and a small seconds dial below the centre. The dial is protected behind a convex glass set in a brass bezel. The 8-day marine chronometer movement is housed in a brass bowl and carried in a brass gimbal ring within the box, arranged to maintain a level running position when in use aboard ship. The plate is stamped JM for John Molyneux , a frame maker from Rainhill, Prescot. Date: circa 1840 Height : 8 ⅜ in (21.2 cm) Width : 7 ½ in (19 cm) Depth : 7 ½ in (19 cm) *John Poole was the head of a London family firm that that was one of the leading makers of marine chronometers in the 19th century. John Poole senior (c.1791–1844) worked from Clerkenwell and, from the early 1830s, traded close to the river at Brunswick Terrace, Commercial Road. This was an advantageous position for supplying mariners and naval officers and he strengthened the firm’s standing through early submissions of their marine chronometers to the Greenwich trials. His sons entered the business: John Poole junior (1818–1867) emerged as the leading adjuster and is best known for inventing “ Poole’s auxiliary ”, a secondary compensation device applied to chronometer balances to reduce middle temperature error, James Poole (1816–1900) worked as a watch and chronometer maker (recorded in Clerkenwell/Pentonville) and remained an important part of the wider workshop output, with the Poole trade continuing in various forms into the later 19th century. For this chronometer dated to around 1840 , the safest attribution is to the Poole workshop founded by John Poole senior and carried forward by his sons immediately after his death . This was a period when instruments could plausibly be in progress under the established business while being finished and adjusted by the younger generation. It is therefore entirely reasonable to describe an 1840 piece as “John Poole” in the senior-founded concern, while noting that, by the mid-1840s, day-to-day adjustment and development work was increasingly associated with John Poole junior and James Poole also active in the business. Poole Marine chronometers are well represented in museum collections today including the Greenwich National Maritime Museum , the Sydney Observatory collection, the Museu Maritim de Barcelona and the Mystic Seaport Museum in the USA. HW6667