The Mortier de 12 pouces Gribeauval (Gribeauval 12-inch mortar) was a French mortar. It was made using the Gribeauval system developed by Jean Baptiste Vaquette de Gribeauval. It was part of the siege artillery. The measurement of the mortar is given by the diameter of the ball. It is measured using the French ancient system of measurement, in which 1 pouce (1 inch) is equal to 2.707 cm. The Gribeauval system was a new way of making artillery as a single piece of metal and then drilling a bore hole. This meant they could be made much lighter and more accurate.