Columbiad

The Columbiad was a large-caliber, smoothbore, muzzle-loading cannon able to fire heavy projectiles at both high and low trajectories. This feature enabled the columbiad to fire solid shot or shell to long ranges, making it an excellent seacoast defense weapon for its day. Invented by Colonel George Bomford, United States Army, in 1811, columbiads were used by the United States coastal artillery from the War of 1812 until the early years of the 20th Century. Very few columbiads were used outside of the U.S. and Confederate Armies; nevertheless, the columbiad is considered by some as the inspiration for the later shell-only cannons developed by Frenchman Henri-Joseph Paixhans some 30 years later.

The first columbiads produced in 1811 had a 7.25-inch (184 mm) diameter bore and fired a fifty-pound projectile. Although some Second System forts were armed with this weapon, the Army did not widely adopt early columbiads due to initial high costs of manufacture. Only after 1844 did an eight-inch (203 mm) model and a ten-inch (254 mm) model see mass production. The eight-inch (203 mm) columbiad could project a 65-pound shell 4,400 yards (4,000 m) or 4,800 yards (4,400 m) for solid shot; the weapon weighed 9,240 pounds (4,190 kg). The ten-inch (254 mm) columbiad weighed 15,400 pounds (7,000 kg) and hefted a 128-pound shell to 4,800 yards (4,400 m) or solid shot to 5,600 yards (5,100 m). These cast iron weapons were typically mounted on seacoast carriages designed to recoil up a slightly inclined set of "rails" or wooden beams. The mounted columbiad could pivot left or right on a traversing rail. In most cases the arc of pivot was less than 180 degrees, but some batteries allowed 360-degree traverse.

...
Wikipedia