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Benthoscope

Unpowered spherical deep-sea observation submersible lowered on a cable

Wikipedia contributorsAdapted for Fathomly · View authors
1 min read
Source updated June 21, 2025
Image credit is listed at the end of this article.

The Benthoscope was a deep sea submersible designed by Otis Barton after the Second World War. He hired the Watson-Stillman Company, who had earlier constructed his and William Beebe's bathysphere, to produce the new design of deep diving vessel, which was named from the Greek benthos, meaning "bottom".

The Benthoscope was essentially similar to the bathysphere, but was built to withstand higher pressures, with a crush depth of 10,000 feet (3,000 m). Its internal diameter was 4.5 feet (1.4 m), and its wall thickness was 1.75 inches (44 mm). It weighed 7 short tons (6,400 kg), an increase in weight of 1,600 pounds (730 kg) over the bathysphere. Two windows of fused quartz were installed, one facing straight ahead and the other diagonally down. Other arrangements followed the bathysphere, with oxygen supplied from cylinders, and calcium chloride and soda lime used to absorb moisture and CO2 respectively.

In August 1949, Barton established a new world depth record with a solo descent to 4,500 feet (1,400 m), which remains the deepest dive by a submersible suspended by a cable.

The Benthoscope is now on display in front of the Los Angeles Maritime Museum in San Pedro, California.

Watch videos about BenthoscopeExplainers and documentaries on YouTube (opens in a new tab)

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This article is adapted from the Wikipedia article “Benthoscope”, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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