Willy Heinrich dives under Antarctic ice - 1902
Even today’s Polar Bear Club members face dangers from extreme temperatures and angry leopard seals. So when Heinrich, then employed as a ship’s carpenter, made his dives during the Deutsche Sudpolar-Expedition, he did so to repair the ship wearing only a Siebe diving helmet (pictured here) and a canvas suit. His under-ice observations were of little scientific use, but he improved his equipment -- no doubt out of self-preservation -- and allegedly built an “ice bicycle” for the crew’s amusement.
Freezing point: Being the go-to-guy for underwater repairs couldn’t have been great fun, but Heinrich made numerous dives, at least once during the Austral winter to free the ship’s anchor, when the surface temperature alone was roughly minus -5.5°c.