The Bathyscaphe Trieste 1, being loaded aboard a support vessel.

The Swiss Auguste Piccard invented the bathyscaphe, which means deep boat. It had two main parts: a cylindrical metal float, from which a steel ball was suspended. The metal float contained gasoline, which provided lift since gasoline is lighter than water. The float also held a couple of tons worth of ballast in the form of iron sheet, scrap iron and gravel.

In 1960 Jacques Piccard (the son of Auguste Piccard) and Navy Lieutenant Donald Walsh descended in the Trieste to the deepest known point on Earth - the Challenger Deep in the Mariana Trench. The two men made the deepest dive in history: 10,915 meters.