Design features reveal that the bathyscaphe was engineered with one goal in mind: to reach the deepest depths of the ocean. In fact, the word "bathyscaphe" takes the first part of its name from the ancient Greek word for "deep": bathys. ("Scaphe" indicates a light, bowl-shaped boat.)

Why was the bathysphere built?

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. ... The record set by the deepest of these, to a depth of 3,028 ft (923 m) on August 15, 1934, lasted until it was broken by Barton in 1949.

What was the Trieste and what did it do?

Trieste is a Swiss-designed, Italian-built deep-diving research bathyscaphe which reached a record depth of about 10,911 metres (35,797 ft) in the Challenger Deep of the Mariana Trench near Guam in the Pacific. It was the first crewed vessel to reach the bottom of the Challenger Deep. ...