A Dahlgren 11-inch smooth-bore naval gun, opposite Yorktown The Dahlgren guns of large caliber were made of cast iron, solid and cooled from the exterior. The powder-chamber was of the “Gomer” form — almost a cone with the base forward and of the size of the bore of the gun, so that when the projectile was rammed home it would not go entirely down to the bottom of the cavity, but would leave a powder-chamber behind it so shaped that the gases had access to a greater surface of the projectile than if the bore had been cylindrical to the base. The 11-inch Dahlgren had a bore of 132 inches in length, a maximum diameter of thirty-two inches, and a weight of 16,000 pounds. The service charge of powder was fifteen pounds, the maximum twenty pounds, and the weight of the solid shot 170 pounds. It sometimes fired a shell weighing 130 pounds. |
A 10-inch Columbiad in battery Semmes With a charge of fifteen pounds of powder this gun, above Farrar's Island on the James River, could throw a shot weighing 123 pounds 3,976 yards, or as far as the Dutch Gap Canal, over two m iles away. |
An 8-inch Parrott and a Rodman gun In this battery at Yorktown are a pear-shaped Rodman gun and the long slim lines of an 8-inch Parrott in front. The latter is reenforced by an extra part shrunk over the powder chamber. |