De Kievit, Menaldum of the "upright shaft" there are two "crown wheels" The upper "crown wheel", which has 35 cogs drives an Archimedes' screw via a "crown wheel". This screw was used to pump water into the polder. The lower "crown wheel", which has 35 cogs, drives a gearwheel with 32 cogs on the axle of an Archimedes' screw, which was used to drain the polder. The axle of the screw is diameter and long. The screw is diameter. It is inclined at 10°. Each revolution of the screw lifts of water. "De Kievit" is open to the public at any time it
Trammel of Archimedes Trammel of Archimedes A trammel of Archimedes is a mechanism that generates the shape of an ellipse. It consists of two shuttles which are confined ("") to perpendicular channels or rails and a rod which is attached to the shuttles by pivots at fixed positions along the rod. As the shuttles move back and forth, each along its channel, the end of the rod moves in an elliptical path. The semi-axes "a" and "b" of the ellipse have lengths equal to the distances from the end of the rod to each of the two pivots. An ellipsograph is a trammel