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The Slocum revolver, designed by Frank Slocum and manufactured by the Brooklyn Arms Company, was one of the more successful workarounds for Rollin White's patent on the bored-through cylinder. The most significant advantage of Slocum's design was its use of standard .32 rimfire cartridges, unlike most other workarounds which used proprietary ammunition. Slocum did this by using a very clever chamber sleeve idea, in which the chambers are actually separate removable pieces that fit in the cylinder.