Ross expedition
The Ross expedition was a voyage of scientific exploration of the Antarctic in 1839 to 1843, led by James Clark Ross, with two unusually strong warships, HMS "Erebus" and HMS "Terror". It explored what is now called the Ross Sea and discovered the Ross Ice Shelf. On the expedition, Ross discovered the Transantarctic Mountains and the volcanoes Erebus and Terror, named after his ships. The young botanist Joseph Dalton Hooker made his name on the expedition. The expedition inferred the position of the South Magnetic Pole, and made substantial observations of the zoology and botany of the region , resulting in a monograph on the zoology, and a series of four detailed monographs by Hooker on the botany, collectively called "Flora Antarctica" and published in parts between 1843 and 1859. The expedition was the last major voyage of exploration made wholly under sail. Among the expedition's biological discoveries was the Ross seal, a species confined to the pack ice of Antarctica. Expedition. Background. In 1838, The British Association for the Advancement of Science proposed an expedition to carry out magnetic measurements in the Antarctic. Sir James Clark Ross was chosen after previous experience working on the British Magnetic  Survey from 1834 onwards, working with prominent physicists and geologists such as Humphrey Lloyd, Sir Edward Sabine, John Phillips and Robert Were Fox. Ross had also had many previous expeditions to the Arctic, including experience as captain. People. The expedition was led by a Captain of the Royal Navy, James Clark Ross, who commanded HMS "Erebus". HMS "Terror" was commanded by Ross's close friend, Francis Crozier. The botanist Joseph Dalton Hooker, then aged 23 and the youngest person on the expedition, was assistant-surgeon to Robert McCormick, and responsible for collecting zoological and geological specimens. Thomas Abernethy, who had  been on previous Arctic expeditions with Ross, was gunner. Hooker later became one of England's greatest botanists; he was a close friend of Charles Darwin, and became director of the Royal Botanical Gardens, Kew for twenty years. McCormick had been ship's surgeon for the second voyage of HMS "Beagle" under Captain Robert FitzRoy, along with Darwin as gentleman naturalist. Ships. The expedition was made in two unusually strong warships, HMS "Erebus" and HMS "Terror". Both were bomb ships, named and equipped to fire heavy mortar bombs at a high angle over defences, and were accordingly heavily built to  withstand the substantial recoil of these three-ton weapons. Their solid construction ideally suited them for use in dangerous sea ice that might crush other ships. The 372-ton "Erebus" had been armed with two mortars – one and one – and 10 guns. Voyage. In September 1839, the "Erebus" and the "Terror" departed Chatham, arriving at Tasmania (then known as Van Diemen's Land) in August 1840. On 21 November 1840 they departed for Antarctica. In January 1841, the ships landed on Victoria Land, and they proceeded to name areas of the landscape after British politicians, scientists, and acquaintances. Mount Erebus , on Ross Island, was named after one ship and Mount Terror after the other. McMurdo Bay (now known as McMurdo Sound) was named after Archibald McMurdo, senior lieutenant of the "Terror". Reaching latitude 76° south on 28 January 1841, they spied ...a low white line extending from its eastern extreme point as far as the eye could discern... It presented an extraordinary appearance, gradually increasing in height, as we got nearer to it, and proving at length to be a perpendicular cliff of ice, between one hundred and fifty and two hundred feet above the level of the sea , perfectly flat and level at the top, and without any fissures or promontories on its even seaward face. Ross called this the Great Icy Barrier, now known as the Ross Ice Shelf, which they were unable to penetrate, although they followed it eastward until the lateness of the season compelled them to return to Tasmania. The following summer, 1841–42, Ross continued to survey the "Great Ice Barrier", as it was called, continuing to follow it eastward. Both ships stayed at Port Louis, in the Falkland Islands for the winter, leaving in September 1842 to explore the Antarctic Peninsula, where they  conducted studies in magnetism, and returned with oceanographic data and collections of botanical and ornithological specimens. The ships arrived back in England on 4 September 1843, having confirmed the existence of the southern continent and charted a large part of its coastline. The Ross expedition was the last major voyage of exploration made wholly under sail. Both the "Erebus" and the "Terror" would later be fitted with steam engines and used for the 1845–1848 Franklin expedition to the Northwest Passage, in which both ships (and all crew) would ultimately be lost. Discoveries. Geography. Ross discovered the "enormous" Ross Ice Shelf , correctly observing that it was the source of the tabular icebergs seen in the Southern Ocean, and helping to found the science of glaciology. He also identified the Transantarctic Mountains and the volcanoes Erebus and Terror, named after his ships. Magnetism. The main purpose of the Ross expedition was to find the position of the South Magnetic Pole, by making observations of the Earth's magnetism in the Southern hemisphere. Ross did not reach the Pole, but did infer its position. The expedition made the first "definitive" charts of magnetic declination, magnetic dip and magnetic intensity, in place of the  less accurate charts made by the earlier expeditions of Charles Wilkes and Dumont d'Urville. Zoology. The expedition's zoological discoveries included a collection of birds. They were described and illustrated by George Robert Gray and Richard Bowdler Sharpe in "The Zoology of the Voyage of HMS Erebus & HMS Terror". The expedition was the first to describe the Ross seal, which it found in the pack ice, to which the species is confined. Botany. The expedition's botanical discoveries were documented in Joseph Dalton Hooker's four-part "Flora Antarctica" (1843–1859). It totalled six volumes (parts III and IV each being  in two volumes), covered about 3000 species, and contained 530 plates figuring in all 1095 of the species described. It was throughout "splendidly" illustrated by Walter Hood Fitch. The parts were: Hooker gave Charles Darwin a copy of the first part of the "Flora"; Darwin thanked him, and agreed in November 1845 that the geographical distribution of organisms would be "the key which will unlock the mystery of species". Influence. In 1912, the Norwegian explorer Roald Amundsen wrote of the Ross expedition that "Few people of the present day are capable of rightly appreciating this heroic deed, this brilliant proof  of human courage and energy. With two ponderous craft – regular "tubs" according to our ideas – these men sailed right into the heart of the pack [ice], which all previous explorers had regarded as certain death ... These men were heroes – heroes in the highest sense of the word." Hooker's "Flora Antarctica" remains important; in 2013 W. H. Walton in his "Antarctica: Global Science from a Frozen Continent" describes it as "a major reference to this day", encompassing as it does "all the plants he found both in the Antarctic and on the sub-Antarctic islands", surviving better than Ross's  deep-sea soundings which were made with "inadequate equipment".