A screw steam corvette of 1,500 tons, which was lent to the Royal Society by the British Admiralty in 1872 for what was to become the most important oceanographic expedition of the era. After being stripped of nearly all her armament, she was fitted out with laboratories and all the necessary equipment to plumb the ocean depths, and became, therefore, the earliest research ship completely dedicated to oceanography. She departed in December 1872 for a circumnavigation that lasted three and a half years during which time she steamed nearly 11,000 kilometres (70,000 mls.). The senior scientist aboard the Challenger was Wyville Thomson (1830–82), who had earlier completed two oceanographic expeditions to discover more about what lay on the ocean bed. His book, The Depths of the Sea (1873), was based on the findings of these expeditions and it is now generally regarded as the first book on the subject.
During the voyage the Challenger took hundreds of soundings, including the first one of the Marianas Trench, also making the discovery that there were mid-ocean ridges (see geological oceanography). She collected thousands of biological samples which showed that at all depths the oceans were teeming with life.
On his return Thomson was knighted by Queen Victoria. Such was the amount of information gained during the circumnavigation that it took the next twenty years to complete the 50-volume Challenger Reports. After Thomson's death, these were edited by his assistant, the geologist John Murray (1841–1914), who had accompanied him on the Challenger. The modern science of oceanography developed from these reports, and Murray is acknowledged to be the founder of geological oceanography. In 1951 scientists aboard a second research ship of the same name were able to sound the bottom of the Marianas Trench for the first time.
Subjects: Maritime History.