Reviews the major deep-sea expeditions from that of HMS Challenger in 1873 to 1960. Emphasis is on the increasing sophistication of vessels and equipment used, the growth of international cooperation and the proliferation of branches of oceanographic studies. Arctic work by Nansen, Sverdrup, recent Soviet scientists, the Scripps Institution and the Norpac program are mentioned (maps). Vessels used during the period and their activities are tabulated. Two maps show cruises of the Atlantic Polar Front Program Jan-Dec 1958 in the Greenland and Barents Sea