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°.
Archimedes of circles. The earliest known copy of the text is in Arabic. The scholars T.L. Heath and Marshall Clagett argued that it cannot have been written by Archimedes in its current form, since it quotes Archimedes, suggesting modification by another author. The "Lemmas" may be based on an earlier work by Archimedes that is now lost. It has also been claimed that Heron's formula for calculating the area of a triangle from the length of its sides was known to Archimedes. However, the first reliable reference to the formula is given by Heron of Alexandria in the 1st century AD.