The measurement of the mortar is expressed by the diameter of the ball, using the French ancient system of measurement, in which 1 pouce (1 inch) is worth 2.707 cm.

However, its first major operational use was even earlier, during the American Revolutionary War, in General Rochambeau's French expeditionary corps, from 1780 to late 1782, and especially at Yorktown in 1781.

[1] The Mortier de 12 pouces used a cylindrical chamber, which, although quite efficient, used to wear easily.

[2] Some of the Mortier de 12 pouces were used in coastal defenses, in which case they were fixed on solid metal platforms.

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