During the development of the 1860 Army revolver, Colt did consider mechanical options other than simply scaling up the 1851 Navy pattern. One of these, as evidenced by this Colt prototype, was an enlarged version of the 1855 Pocket, aka Root, revolver. That 1855 design used a solid frame and had been the basis for Colt’s revolving rifles and shotguns, and so it would be natural to consider it for use in a .44-caliber Army revolver. How extensive the experimentation was is not known, and I believe this is the only known surviving prototype of a Dragoon-size 1855 pistol. It survives in excellent shape, and is a really neat glimpse at what might have been…