Bathysphere

Unpowered spherical deep sea observation submersible lowered on a cable
the particular deep diving device

The Bathysphere 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 922.93 m on August 15, 1934, lasted until it was broken by Barton in 1949 in a vessel called Benthoscope.

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 8 square miles (21 km2) area of ocean, from a depth of 2 mile (3 km) 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 several hundred feet. Submarines of the time had descended to a maximum of 116.74 m, 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 160.02 m 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. These articles caught the attention of the engineer Otis Barton, who had his own ambition to become a deep sea explorer. Barton was certain that a cylinder would not be strong enough to withstand the pressure of the depths to which Beebe was planning to descend, and sent Beebe several letters proposing an alternative design to him. So many unqualified opportunists were attempting to join Beebe in his efforts that Beebe tended to ignore most of his mail, and Barton's first efforts to contact him were fruitless. Barton's design called for a spherical vessel, as a sphere is the best possible shape for resisting high pressure. Initially only two of the windows were mounted on the sphere, and a steel plug was mounted in place of the third window. Beebe and Barton conducted several successful dives during the summer months of 1930, documenting deep sea animals which had never before been seen in their native habitats. During these dives, Beebe became the first person to observe how as one descends into the depths of the ocean, some frequencies of sunlight disappear before others, so that below a certain depth the only colors of light that remain are violet and blue. After packing the plug in more securely, and sending the Bathysphere down for another test dive in which the plug held, Beebe and Barton set off for their radio dive on September 22. The Bermuda Aquarium, Museum and Zoo (to which Beebe had given some of Bostlemann's original drawings) has long displayed a copy of the bathysphere, and another reproduction is on display at the National Geographic Museum.

Although the technology of the Bathysphere was eventually rendered obsolete by more advanced diving vessels, Beebe and Barton's Bathysphere represented the first time that researchers attempted to observe deep sea animals in their native environment, setting a precedent which many others would follow. One possibility is that although the animals described by Beebe indeed exist, so much remains to be discovered about life in the deep ocean that these animals have yet to be seen by anyone other than him. Although the term "Bathysphere" originally referred specifically to the vessel used by Beebe and Barton, more recently movies and video games have begun to use the term "bathysphere" for any spherical deep sea vessel lowered on a cord. In the movie Warlords of Atlantis, a vessel called a bathysphere is the means of transportation for the characters in and out of the Atlantis. In the video game BioShock, a bathysphere is the means of transportation to and around the undersea city of Rapture. In the video game Psychonauts, a vessel called a bathysphere is used for transport to an area at the bottom of the camp's lake. In the episode "Twenty Years to Midnight" of the animated television series The Venture Bros., Action Johnny is found living in a bathysphere, feeding his addiction to heroin and other narcotics.