Bathyspheres

The bathysphere, a sealed gondola capable of maintaining interior pressure at great ocean depths, was devised to overcome the limitations of previous diving equipment. Designed as a sphere with quartz windows, Beebe descended about a kilometer underwater in this vessel.
 Charles William Beebe United States 1934 Bathyspheres

The bathysphere, a sealed gondola capable of maintaining interior pressure at great ocean depths, was devised to overcome the limitations of previous diving equipment. Designed as a sphere with quartz windows, Beebe descended about a kilometer underwater in this vessel.