What is the detachable fore part of a gun carriage, consisting of two wheels, an axle, and a shaft to which the horses are attached. On top is an ammunition box upon which the cannoneers sit called?

limber — (Mil.) The detachable fore part of a gun carriage, consisting of two wheels, an axle, and a shaft to which the horses are attached. On top is an ammunition box upon which the cannoneers sit. (Webster's 1913.)

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