This Exploded View first appeared in the September 1995 issue of American Rifleman.
Most of us think of O.F. Mossberg & Sons as a major producer of rifles from 1922 to 1986 and a mammoth shotgun maker today. But founder Oscar Mossberg's first product was neither rifle nor shotgun but a repeating pocket pistol.
In 1919, Mossberg, his sons Iver and Harold, and a single employee set up in a loft in New Haven, Connecticut, and made the first of some 37,000 Brownie pistols that continued in production until 1932. The principles behind the $5-range pistol involved a break-open action; four 2V' barrel tubes that were chambered for the .22 Long Rifle cartridge and rifled in a single cluster; a firing pin that retracted, rotated 900 and then fell after each long trigger pull to fire each chambered cartridge in succession.
Above all, the Brownie offered simplicity and economy in a highly portable package. It was, in a sense, the Sharps derringer brought up to date. 
Additional Reading:
2019 First Look: Mossberg MC1sc Pistol
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