At the end of the American Civil War, one thing became clear in the world of handguns. The era of the percussion revolver was over, and the era of the self-contained metallic cartridge had arrived. Except for the folks at Smith & Wesson, that posed a problem for just about all the other manufacturers as S&W at that stage held the exclusive rights to the Rollin White patent of the bored-through cylinder design. Everybody had to come up with some creative idea to develop a functioning handgun to stay in business without falling foul of the Rollin White patent. Colt was one of the manufacturers and they found a solution via one of their employees, Alexander Thuer. Although complicated, the design did circumvent the Rollin White patent as the cartridges were slightly tapered and loaded from the front and not from the rear. The design was ultimately not very successful, and it is speculated that less than 5,000 of these conversions were done. It was also in 1869 that the Rollin White patent expired, although the Thuer conversions were still done up to 1872. (Erlmeier, Brandt Ref. 346)
