Note 1 — Chapter III · THE FORTIFICATIONS.
Reading edition
: The exact figures of this Armstrong Gun are: Weight, 101.2 tons. Length, 32.65 feet. Length of bore, 30.25 feet. Diameter of bore, 17.72 inches. Length of charge of powder, 5 feet. Weight of charge, 450 pounds. Weight of shot, 2,000 pounds. Velocity at the muzzle, 1,548 feet per second. At such velocity, a ball of such weight would have a "smashing effect" of 33.230 "foot-tons," and would penetrate 24.9 inches of wrought iron. Range, when fired at the highest elevation, over 8 miles.