Challenger expedition

The Challenger expedition of 1872–1876 was a scientific exercise that made many discoveries to lay the foundation of oceanography. The expedition was named after the mother vessel, HMS Challenger. Prompted by Charles Wyville Thomson—of the University of Edinburgh and Merchiston Castle School—the Royal Society of London obtained the use of Challenger from the Royal Navy and in 1872 modified the ship for scientific tasks, equipping her with separate laboratories for natural history and chemistry. The expedition, led by Captain George Nares, sailed from Portsmouth, England, on 21 December 1872. Other naval officers included Commander John Maclear. Under the scientific supervision of Thomson himself, she travelled nearly 70,000 nautical miles (130,000 km; 81,000 mi) surveying and exploring. The result was the Report Of The Scientific Results of the Exploring Voyage of H.M.S. Challenger during the years 1873–76 which, among many other discoveries, catalogued over 4,000 previously unknown species. John Murray, who supervised the publication, described the report as 'the greatest advance in the knowledge of our planet since the celebrated discoveries of the fifteenth and sixteenth centuries'. Challenger sailed close to Antarctica, but not within sight of it. To enable her to probe the depths, 15 of Challenger's 17 guns were removed and her spars reduced to make more space available. Laboratories, extra cabins and a special dredging platform were installed. Challenger used mainly sail power during the expedition; the steam engine was used only for powering the dredge. She was loaded with specimen jars, filled with alcohol for preservation of samples, microscopes and chemical apparatus, trawls and dredges, thermometers, barometers, water sampling bottles, sounding leads, devices to collect sediment from the sea bed and great lengths of rope with which to suspend the equipment into the ocean depths. Because of the novelty of the expedition, some of the equipment was invented or specially modified for the occasion. In all, she was supplied with 181 miles (291 km) of Italian hemp for sounding. On her 68,890-nautical-mile (79,280 mi; 127,580 km) journey circumnavigating the globe, 492 deep sea soundings, 133 bottom dredges, 151 open water trawls and 263 serial water temperature observations were taken. About 4,700 new species of marine life were discovered. The scientific work was conducted by Wyville Thomson, John Murray, John Young Buchanan, Henry Nottidge Moseley, Alphonse François Renard and Rudolf von Willemoes-Suhm. Frank Evers Bed was appointed prosector. The official expedition artist was John James Wild. As well as Nares and Maclear, others that were part of the naval crew included Pelham Aldrich, George Granville Campbell, and Andrew Francis Balfour (one of the sons of Scottish botanist John Hutton Balfour). Also among the officers was Thomas Henry Tizard, who had carried out important hydrographic observations on previous voyages. Though he was not among the civilian scientific staff, Tizard would later help write the official account of the expedition, and also become a Fellow of the Royal Society. The original ship's complement included 21 officers and around 216 crew members. By the end of the voyage, this had been reduced to 144 due to deaths, desertions, personnel being left ashore due to illness, and planned departures.