Bathysphere

The Bathysphere (Greek: βαθύς, bathus, "deep" and σφαῖρα, sphaira, "sphere") was a unique spherical deep-sea submersible which was unpowered and lowered into the ocean on a cable, and was used to conduct a series of dives off the coast of Bermuda from 1930 to 1934. The Bathysphere was designed in 1928 and 1929 by the American engineer Otis Barton, to be used by the naturalist William Beebe for studying undersea wildlife. Beebe and Barton conducted dives in the Bathysphere together, marking the first time that a marine biologist observed deep-sea animals in their native environment. Their dives set several consecutive world records for the deepest dive ever performed by a human. The record set by the deepest of these, to a depth of 3,028 feet on August 15, 1934, lasted until it was broken by Barton in 1949.

In 1928, the American naturalist William Beebe was given permission by the British government to establish a research station on Nonsuch Island, Bermuda. Using this station, Beebe planned to conduct an in-depth study of the animals inhabiting an eight-mile-square area of ocean, from a depth of two miles to the surface. Although his initial plan called for him to conduct this study by means of helmet diving and dredging, Beebe soon realized that these methods were inadequate for gaining a detailed understanding of deep-sea animals, and began making plans to invent a way to observe them in their native habitat.

As of the late 1920s, the deepest humans could safely descend in diving helmets was 100 feet, since beyond that point the pressure becomes too great.Submarines of the time had descended to a maximum of 383 feet, but had no windows, making them useless for Beebe's goal of observing deep-sea animals. The deepest in the ocean that any human had descended at this point was 525 feet wearing an armored suit, but these suits also made movement and observation extremely difficult. What Beebe hoped to create was a deep-sea vessel which both could descend to a much greater depth than any human had descended thus far, and also would enable him to clearly observe and document the deep ocean's wildlife.

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