1.   The chicken launcher was a two-stage operation, Hart says, involving a powder charge and compressed hydrogen.

2.   The most challenging game involves choosing the perfect angle and powder charge to send Gonzo the Cannonball across the stage and through a target while he emits classical tunes.

3.   It contains small powder charges in the muzzle, rather than in a slug farther back in the weapon.

4.   The Hunley rammed a black powder charge at the end of a spar into the Union ship.