http://www.rockislandauction.com/viewitem/aid/1025/lid/2314

The Moore patent "teatfire" revolver was one of the more (no pun intended) successful workarounds to the Rollin White patent. Designed by Daniel Moore and David Williamson, the gun was a 6-shot .32 caliber pocket revolver which used a proprietary type of cartridge. It was loaded from the front, and the rear of the case had a nipple in its center full of priming compound. This allowed the rear of the cylinder to only have a small hole through which the hammer could reach to hit the nipple and fire the round, as opposed to a rimfire design in which the whole rear of the cartridge had to be exposed at the back of the cylinder. Some examples, including this one, included a unique type of extractor for pushing out spent cases.