What is (a) A tool used in driving down compactly the composition contained in a rocket, or like firework. (b) A deviation from the line of fire, peculiar to oblong projectiles called?

drift — (Mil.) (a) A tool used in driving down compactly the composition contained in a rocket, or like firework. (b) A deviation from the line of fire, peculiar to oblong projectiles. (Webster's 1913.)

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