Set sail December 21, 1872,
Portsmouth, England
Docked May 24, 1876,
England

The idea for the H.M.S. Challenger expedition, which investigated the physical and biological properties of the world’s oceans, began with two British naturalists, William B. Carpenter and Charles Wyville Thomson. Having already dredged in the North Atlantic Ocean off the coast of Britain, they realized a wealth of information could be obtained from the oceans if they were examined in a systematic way.

Prompted by Carpenter, the Royal Society, the major scientific society in Great Britain, asked the British Admiralty to supply a ship and crew to make such a voyage. The request was granted. Naval command was given to Sir George Nares, while Thomson was put in charge of scientific research. The instructions given to these men were to:

investigate the physical condition of the deep sea throughout the...