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First deep-ocean dive

First deep-ocean dive
Who
William Beebe, Otis Barton
Where
Not Applicable
When
15 August 1934
On 15 August 1934, William Beebe (USA, 1877–1962) and Otis Barton (USA, 1899–1992) descended to a then-record depth of 923 m (3,028 ft) in a tethered bathysphere off Bermuda in the Caribbean. Beene led the expedition while Barton designed the bathysphere, the depth of which was limited by the steel cable (and telephone line) that connected it to the surface. This remained the deepest dive by humans until Barton broke the record in 1949.