While preparing book talks for my forthcoming title, The Heroic Age of Diving, I came across a long forgotten, failed attempt at self-contained underwater breathing apparatus–in 1855!
So far, no other experts I’ve checked with recognize Levy’s name. However, Levy was not the only one working on the concept in the late 1840s and early 1850s. Another Frenchman, Pierre Aimable De Saint Simon Sicard, patented an underwater rebreather design in 1849; and Theodore Schwann, a German professor living in Belgium invented a rebreather for miners in 1853.
But Levy’s device appears to be different in that he had an oxygen bladder rather than a tank. The lime and caustic soda carbon dioxide scrubber was fairly well-known by the 1850s.
The only other reference I’ve found relates the same story, with additional details, from the October 27, 1855 edition of Scientific American:
Had Levy been a bit more cautious in his testing, the history of diving might have changed dramatically.