George Martin
The Shipboard Behemoths
The battles for control of Southern coastal forts were dominated by artillery duels between the most powerful weapons of the Civil War--heavy, large-caliber naval guns with bores of 6 to 15 inches in diameter. These big guns employed a wide range of highly destructive ammunition, such as the massive 11-inch, 121-pound shell at left [photo]. Ammunition for the smooth-bores was generally spherical, and for the rifled guns, conical.
By the start of the War, the shell appeared to have established its superiority over the old-fashioned cannonball by virtue of its explosive force. But the invention of ironclad vessels revived the use of solid shot, which when fired cannon, was capable of piercing the ships' armor.