is possible that production started several years earlier. Production almost certainly ended before the end of the Wheelock era (c 1864). This is based on no more than the logic of simplifying production. In 1861, it is possible that Allen produced the bar-hammer, side-hammer, and center-hammer percussion revolvers as well as the rimfire and lipfire cartridge revolvers simultaneously! Because demand from the Civil War was consuming just about any arm produced, it would have made sense to cease production of the less advanced models. The lineage of the pepperbox is clear in the cylinder design, grip design, standard-style trigger, and patented bar hammer double-action design. This may represent simple design evolution, as the double action pepperbox 'pocket pistols' were very popular in the market. Allen may have been counting on visual and functional design similarity to help sell these revolvers. The design may also be very thoughtful in regards to avoiding patent issues. By incorporating his unchallenged 1845 patent for the bar-hammer double-action mechanism, Allen may have wished to avoid any patent infringement problems from Colt for his own revolving mechanism IF the revolver was produced before the expiry of the Colt patent in 1857. Considering all of the evidence that Allen was a thoughtful and frugal businessman, it may simply demonstrate that using common parts was less expensive than designing new ones. Finish was blued, with wood grips as standard, though ivory could be had for an extra cost. The Allen bar-hammer is actually quite advanced in that pulling the trigger advances the cylinder, cocks the hammer and drops the hammer, firing the weapon. The cylinder can be removed for cleaning with the removal of cylinder pin. A separate rammer would be needed for loading. It is likely that the cylinder would be removed for loading, so reloading under duress is not practical. The author finds these revolvers aesthetically pleasing and very practical for a pocket pistol. This style was manufactured and sold in three different sizes. Small frame Bar-Hammer revolver The small frame is a five-shot, .28 caliber revolver, though some .30 caliber models are known. The barrel is 2.5 inches long. The cylinder is engraved with a scene of forest animals identical to the 'pocket-size' side-hammer percussion revolver. As with many models, changes were made during production, and collectors note an 'early' and 'late' variation. Mid frame Bar-Hammer revolver The mid frame is a five-shot, .32 caliber