The origin of the multi-chamber gun dates back to the 19th century. In 1857, U.S. inventor Azel Storrs Lyman (1815–1885) was granted a patent on "Improvement in accelerating fire-arms",[6] and he built a prototype in 1860 which proved to be unsuccessful.[7][8] Lyman then modified the design in collaboration with James Richard Haskell, who had been working for years on the same principle.[9][10]