S6670 Spade

S6670  Spade

Designed approximately around 1690 by Papin the design was a rudimentary strong and heavy metal and wood square box that used an air pump to achieve buoyancy. Rudimentary yet ornate with spade like iron decorations and heavy iron conning tower buoyancy proved a difficult thing and his two inventions sank or were destroyed by angry boatbuilders who felt threatened.  His attempts at submersibles were overshadowed by his invention of the "steam digester” which developed into the modern day pressure cooker.