Do not Rule out the Derringer
The humble derringer-style pocket gun has served western civilization for a large part of the past three centuries. The original Derringer was the Philadelphia Deringer (note, just 1 R) invented by one Mr. Henry Deringer, around 1825. His pistol, usually a large caliber single shot fired by the then-novel percussion cap, made him much more money or fame than the Model 1814 or 1817 rifles he designed for the Army or the dueling pistols he lavished attention on. His guns were so popular that they were imitated (here’s where you see the imitators used two R’s).
Read more in my column at Firearms Talk.com