Cross section of one of the two gun towers on Fort Island Pampus. In the middle a cross-section of a gun tower drawn by Henk Tol, a volunteer at Fort IJmuiden. Unfortunately, there is nothing left of it now. To the left of the 2 towers an animation of one of the two turret brakes and to the right an animation of the accumulators that provided constant pressure for the hydraulic systems in the turret, such as the elevation of the cannons, the boosters and the turret brakes. On the far right is one of the two boosters, which pushed the heavy shells into the gun barrel.