Pettengill Army Model Double Action revolver manufactured by Rodgers & Spencer & Co., of Willow Dale, New York. There were approximately 3,400 total Pettengill Army revolvers manufactured, with this example included as one of 2,000 purchased by the U.S. Ordnance Department between October 1862-January 1863. The Pettengill double action revolver is known for fouling internal parts after several discharges, which made it nearly impossible to fire. Pettengill Army revolvers were issued in quantity to the 3rd Michigan Volunteer Cavalry and in small numbers to several other Midwestern cavalry regiments. The top strap is marked "PETTENGILLS/PATENT 1856/PATD JULY 22 1856/& JULY 27 1858". The serial number "4231" is stamped on the side of the cylinder, inside of the trigger guard, underside of both grips, and on the butt. "W" sub-inspection mark on the left side of the loading lever and bottom flats of both grip panels, and "WW" on the left of the barrel and frame. Boxed script "NW" (Nathaniel Whiting) inspection cartouche stamped on the left grip panel.