The Volcanic repeating pistol was the first direct step along the development path of the lever-action rifle that became an icon of the American West. Introduced before the advent of modern brass-cased cartridges, the Volcanic was notable for both its repeating action and the self-contained ammunition that made it practical. Volcanic pistols (and rifles) are quite rare today, but they are a pretty cool corner of firearms history. Well, Edmund Lewis and Stephen Rutter wrote a gorgeous book on the history of the Volcanic, with more than 340 glossy color photos of some really impressive specimens: http://www.forgottenweapons.com/book-review-volcanic-firearms/