Development of submersibles
Humans have attempted to design diving suits that would extend underwater stays beyond the capacity of their lungs since antiquity.
Cornelis Jacobszoon Drebbel, the court inventor of the English King James I, built the first navigable submarine in 1620. It was a fishing boat equipped with oars and snorkels and had a hull sealed with goat skins. The bow was flattened to push it under water as soon as it began to move. The vessel was able to reach a depth of 3.6 meters and reportedly went from Greenwich to Westminster.
The first German submarine was tested in Lake Steinhude in 1772. The wooden "pike" had the form of a fish and stayed under water for up to 12 minutes. "Turtle", the first real submersible, was built in 1776 by the American David Bushnell. It was driven by two hand-cranked screw propellers and unlike its predecessor models had no oars or sails.
The invention of the steam engine and the storage battery accelerated the development in the 19th century. Given their utility for military purposes, many investments were made in the construction of submarines. However, military submarines were only able to reach depths of 600 and in some cases, 900 meters. Although research submersibles can reach much greater depths and are smaller and more agile, they usually have a limited range.
The most famous of them was "Trieste", a so-called bathyscaphe ("deep boat"). This term coined by its builder, Auguste Piccard, describes a submersible with a pressure hull for observation purposes and a ballast tank. Trieste was developed by Auguste Piccard in 1952 and made her maiden voyage in 1953. She broke several depth records and ultimately set the depth record of approx. 10,910 meters that is valid to this day when she reached the Challenger Deep in the Mariana Trench on January 23, 1960. She was crewed by the Swiss Jacques Piccard, the son of the boat's builder, Auguste Piccard, and the American Don Walsh. The Trieste had a pressure hull made by Krupp in Essen and a viewing pane made of conically shaped Plexiglas. One of these doors today is owned by the Rebikoff-Niggeler Foundation in the Azores.
It took until March 2012 for another attempt to dive to Challenger Deep, in a voyage made by the filmmaker James Cameron in the Deepsea Challenger.