Howitzers fall somewhere between guns and mortars, the other main artillery types. Like guns, they can be moved, if slowly. They do not fire straight at the target, but lob shots high into the air to plunge down on a target. The charge of powder and the barrel angle can be varied, which means a howitzer can lob missiles over a wall or intervening woods. In close action, they can fire canister rounds directly into enemy formations, blasting them with hundreds of musket balls. These experimental batteries can also fire carcass shells and quicklime rounds, setting fire to enemy structures or poisoning enemy troops with caustic chemicals.
Historically, ballistics was not an imperfectly-understood science and, apart from inaccurate targeting, a shell did not necessarily do any damage when it arrived. Erratic winds could send shells off course. Shell fuses had to be lit while still in the barrel, and the length of fuse judged to match the flight time. If the fuse was too short, the shell could explode in mid air; too long and the enemy might be able to put it out before it exploded!