Note 18 — BOMMEL.

“This excellent manner of defending places is practised thus,” says Grotius in his description of this siege: “when a city which dreads a siege has many soldiers, the fortifications are carried outwards to a distance, to stop the progress of the enemy. By this means those who are shut up have a longer time to defend themselves, and still further, the internal parts of the place remain longer in safety. Thus then the prince of Orange gave orders that, before the boulevards of Bommel, others should be made, and then still others, which should be inclosed with a fosse of water, as well as the preceding ones, so that in the end, all that was capable of defence should be further surrounded by a parapet.”—Annals of Grotius. This, then, is the origin of the multiplication of the exterior works of places of war and of the covered way, to which Grotius gives the name of parapet. Engineers have since made it their study that all fortifications should sustain one another, and might be, at the same time, sustained by the body of the place.