De Olifant, Burdaard Archimedes' screw. This Archimedes' screw has an axle diameter of and is diameter overall. It is inclined at an angle of 17½°. Each revolution of the screw lifts of water. The drive to the smaller of the two Archimedes' screws that drain the polder is from a 36 cog gear wheel meshing with the "great spur wheel". This drives a 33-cog gear wheel which drives the Archimedes' screw via a 41-cog gear wheel on the axle of the Archimedes' screw. This Archimedes' screw has an axle diameter of and is diameter overall. It is inclined at an angle of 121°.
Screw meaning of the word "screw" has long involved the idea of a helical screw thread, but the Archimedes screw and the screw gimlet (like a corkscrew) preceded the fastener. The word "bolt" is also a very old word, and it was used for centuries to refer to metal rods that passed through the substrate to be fastened on the other side, often via nonthreaded means (clinching, forge welding, pinning, wedging, etc.). The connection of this sense to the sense of a door bolt or the crossbow bolt is apparent. In the 19th century, bolts fastened via screw threads were often