Staff Writer (Updated: 11/26/2013):
The Model 1870 was of a clean design. Most notable regarding its appearance was the use of an "open-frame" describing how there was no structural "bridge" spanning across the cylinder. The cylinder was smooth-sided and sat within the frame just above the trigger group and pistol grip. The trigger itself was housed within an oblong ring while the hand grip was a slender checker-gripped protrusion made to fit comfortably in the hand. The hammer was seated above the pistol grip while the barrel was rounded and fitted the forward sight. The revolving cylinder held six cartridges of 11mm caliber and firing was of double-action. The double-action method was credited to British gunsmith Robert Adams and simply implied that the pulling of the trigger performed the two functions of 1) cocking the hammer and 2) releasing it to strike the base of the chambered round. In a revolver, this action also included the revolving of the cylinder chambers to supply a fresh cartridge base to the hammer.