JAMES CLARK ROSS (1800-1862)
The Chronometer of HMS Erebus used by Captain Ross on the voyage of the Erebus and Terror to the Antarctic in 1839-1843.
An early Victorian Eight-Day Royal Greenwich Observatory marine chronometer. ARNOLD & DENT No. 1212 (circa 1839). The silvered dial signal ARNOLD & DENT 84 Strand, London, No. 1212, Roman hour numerals, subsidiary second dial (at VI) with Arabic numerals and inscribed "with AIRY'S COMPENSATION" and the Government Mark up-and-down dial (at XII) inscribed "UP 1-2-3-4-5-6-WIND all hands of blued steel, main frame assembly carry fusée, barrel and centre wheel, the top plate inscribed with the Government Mark, sub-frame assembly carrying the remainder of the train, Earnshaw escarpment, cut bimetallic Pennington format balance with AIRY'S COMPENSATION, blued steel helical balance spring, dovetail spring detent with jewelled locking strone to side with convex glass, gimballed in brass bound three-tier mahogany box (probably later), mother-of-pearl disc (unsigned) to front of middle section, trade label of NEGUS NAUTICAL INSTRUMENTS 69 PEARL STREET, NEW YORK on inside, flush recessed brass handles.
Dial diameter 112mm.: Box 120mm. square
Sub-frame assembly: This is numbered 1212 in three places
a. underside of bottom plate
b. on balance cock
c. on balance cock support
Main frame: This carries the frame maker punch T.G.W
Dial: is numbered 1212 on the reverse. The AIRY'S COMPENSATION, a later adaption named after the astronomer royal, was fitted between 15 Nov. 1882 and 15. January 1883.
AN IMPORTANT POLAR CHRONOMETER -- ONE OF THE FIRST TO BE USED TO NAVIGATE ANTARCTIC WATERS AND PLOT THE COASTLINE OF THE ANTARCTIC CONTINENT.
In 1838 John Barrow and the Admiralty planned a special expedition to the Antarctic, refitting two bomb vessels for Polar use. Ross, with his experience og Arctic navigation and his skill at magnetic observations, was the obvious choice to lead the expedition. He was appointed to the command of the Erebus on 8 April 1839 with Captain Francis Crozier appointed to the Terror. The two ships were refitted with final inspections by the Admiralty on 2 September 1839. The chronometer was released to the Erebus on 30 August and the ships sailed on 5 October for Tasmania, stopping at Kerguelen Island before arriving in Hobart on 16 August 1840. By 1 January 1841, the expedition had crossed the Antarctic Circle, pushed through the ice and sailed into the sea that would be named for Ross, planting a flag on Possession Island, and claiming the Antarctic coastline of 'Victoria Land', and naming the volcanoes on 'Ross Island' Mount Erebus and Mount Terror. The two vessels continued along the Ice Barrier (which came to be known as the Ross Ice Shelf) looking for an opening until well into February and then returned to the Derwent River, Hobart. The following November they set off south again and despite heavy ice reached the Ice Shelf by February, again sailing eastwards. By March Ross was forced to sail north, until a collision forced them to retreat to the Falklands for repairs to Erebus over the winter. In December 1842 Ross tried again to go south but could not penetrate the pack, and headed home, arriving in Folkestone on 4 September, 1843.
The chronometer was returned to the Admiralty from the Terror on 13 September 1843. The voyage had lasted 4 years and 5 months, during which the ships had surveyed large areas of the Antarctic, had taken magnetic readings, gathered oceanographic data and large collections of botanical and ornithological specimens (under the guidance of the assistant surgeon Joseph Hooker).
The chronometer played an important role in the development of navigation in the 19th century. The introduction of accurate clocks by Harrison in the late 18th century allowed mariners to calculate their position of longitude to an accuracy of a few nautical miles, a considerable improvement on using lunar tables. Ross's expedition was fitted out with scientific instruments of the highest quality to fulfil the Royal Society's demanding scientific program (outlined in their 100-page volume), which, aided by Ross's 'well-known scrupulosity and exactness in their use', were confidently expected to deliver results. The expedition's results were published by Sabine over the twenty-five years following their return. In spite of their ambitions, inadequate instruments were later blamed for errors in their oceanogrpahical findings.
This particular chronometer was subsequently used by the Admiralty in a number of vessels with spells in HMS Plymouth, and extensive use on the schooner Gulnare from 1849-1865. The schooner was a surveying vessel under the command of Admiral H W Bayfield, which mapped and charted the eastern seaboard of Canada and the Great Lakes. In 1883 the chronometer was in use on HMS Northampton, under the command of Admiral McClintock, the very same Admiral McClintock who had helped discover the fate of the the Erebus and Terror on Sir John Franklin's Last Expedition.