The Parrott rifle was a type of muzzle-loading rifled artillery weapon used extensively in the American Civil War. Parrott rifle The gun was invented by Captain Robert Parker Parrott, a West Point graduate. He was an American soldier and inventor of military ordnance. He resigned from the service in 1836 and became the superintendent of the West Point Foundry in Cold Spring, New York. He created the first Parrott rifle (and corresponding projectile) in 1860 and patented it in 1861. Daniel Treadwell, who developed a method for making built-up guns in early 1840s, tried to claim that his patent infringed on an earlier one, but in 1866 S.D.N.Y. court dismissed it, deciding that Treadwell's claim was invalidated by a 1843 British patent to John Frith. Parrotts were manufactured with a combination of cast and wrought iron. The cast iron made for an accurate gun, but was brittle enough to suffer fractures. Hence, a large wrought iron reinforcing band was overlaid on the breech to give it additional strength. There were earlier cannons designed this way, but the method of securing this band was the innovation that allowed the Parrott to overcome the deficiencies of these earlier models. It was applied to the gun red-hot and then the gun was turned while pouring water down the muzzle, allowing the band to attach uniformly. By the end of the Civil War, both sides were using this type of gun extensively. Parrott rifles were manufactured in different sizes, from the 10-pounder Parrott rifle up to the rare 300-pounder. In the field, the 10- and 20-pounders were used by both armies. The 20-pounder Parrott rifle was the largest field gun used during the war, with the barrel alone weighing over . The smaller size was much more prevalent; it came in two bore sizes: and . Confederate forces used both bore sizes during the war, which added to the complication of supplying the appropriate ammunition to its batteries. Until 1864, Union batteries used only the 2.9-in. The M1863, with a 3-in bore, had firing characteristics similar to the earlier model; it can be recognized by its straight barrel, without muzzle-swell. Its range was up to with a trained crew. On June 23-24, 1862, President Abraham Lincoln made an unannounced visit to West Point, where he consulted with retired Gen. Winfield Scott regarding the handling of the Civil War and the staffing of the War