A derringer is a small pocket pistol named after Henry Deringer, a famous 19th-century small pistols maker. Many copies of his original Philadelphia Deringer pistol were made by other gun makers worldwide, and the name was often misspelled; this misspelling soon became an accepted term for any pocket pistol, along with the term palm pistol, which Deringer's competitors invented and used in their advertising. The original Deringer pistol was a single-shot muzzle loading pistol; with the rise of cartridge firearms, pistols began to be produced in the modern form are still known as a derringer.
A derringer is usually the smallest usable handgun of a given caliber. They were often 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 those used in semi-automatic handguns or revolvers would add more size to the gun, defeating the purpose of hiding it.
The little derringer featured in this post, the BTJ Derringer, was made by Bellmore Johnson Tool Company in Hamden, Connecticut and is chambered in .38 special caliber rounds. It can fire two shots.
Original BTJ's were only made one year in 1985. A very collectible firearm indeed.
Sources: infospaze.com/Derringers
https://www.gunsamerica.com/975299195/BTJ-DA-38SPL-Derringer.htm
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