The term derringer is a genericized misspelling of the last name of Henry Deringer, a famous maker of small pocket pistols in the 1800s. Many copies of the original Philadelphia Deringer pistol were made by other gun makers worldwide, and the name was often misspelled; this misspelling soon became a generic term for any pocket pistol. The original Deringer pistol was a single-shot muzzleloading pistol; with the advent of cartridge firearms, pistols began to be produced in the modern form still known as a derringer. A derringer is generally the smallest usable handgun of a given caliber. They were frequently used by women, because they are easily concealable in a purse or as a stocking gun. Derringers are not repeating firearms—repeating mechanisms such as used on semi-automatic handguns or revolvers would add significant bulk to the gun, defeating the purpose. The original cartridge derringers held only a single round, usually a pinfire or rimfire .40 caliber cartridge, with the barrel pivoted sideways on the frame to allow access to the breech for reloading. The famous Remington derringer design doubled the capacity, while maintaining the compact size, by adding a second barrel on top of the first and pivoting the barrels upwards to reload. Each barrel then held one round, and a cam on the hammer alternated between top and bottom barrels. The Remington derringer was in .41 Rimfire caliber and achieved wide popularity. The .41 Rimfire bullet moved very slowly, at about 425 feet per second (a modern .45 ACP travels at 850 feet per second). It could be seen in flight, but at very close range, such as at a casino or saloon card table, it could easily kill. The Remington derringer was sold from 1866 to 1935.
