Exploring the Depths of the Ocean

Apparently ocean exploration began around 5000BC!
I am going to concentrate on 1930s+ and the creation of the firstbathysphere
(from the Greek ’ bathus’ meaning ‘deep’ and ‘sphaira’ meaning ‘sphere’) which was a unique, unpowered, spherical deep-sea submersible which was lowered into the ocean by cable. It was created/designed by American Otis Barton an inventor and actor.

Otis and William Beebe ( a naturalist)- made a dive off Bermuda in June 1930. The dive was conducted from the deck of a former British naval ship called the *Ready.

They set the first record for deep-sea diving by descending to 600 ft. (180 m).
In 1934 they improved the record to 3,028 ft ( 923m).

Otis in 1949 set a new world record of 4,500 ft (1,372m) in the Pacific Ocean with the benthoscope (from the Greek ’ benthos’- meaning ‘sea bottom’ and ‘scopein’ to ’ view’). It was designed by Otis and Maurice Nelles.

(Jacques-Yves Cousteau (1910-1997) - a French man and co-developer of the Aqua -Lung- deserves a mention because through his 120 television documentaries and 50 books he permitted many through viewers/readers to explore the resources of the oceans.)

Jacques Piccard (1922-2008) was a Swiss oceanographer and engineer. He was known for developing submarines for studying ocean currents. In the bathyscaphe Trieste Jacques with his colleagues reached 24,000 feet.
Jacques with Lt.Don, of the US Navy, on January 23, 1960 were the first to explore the deepest known part of the world’s ocean, the Challenger Deep, in the Mariana Trench, located in the western North Pacific . The depth measured 35,813 feet (10,916 m) - a more accurate measure later 35,798 ft (10,911 m).

Others have followed - James Cameron(2012 first solo descent), Victor Vescovo, Kathryn D.Sullivan and Vanessa 0’Brien (read their stories)

The Deepsea Challenger was built in Australia in 2012 - construction was headed by Ron Allum ( Read development). J

Sources
Encyclopedia of Great Explorers
Wikipedia