Model of Archimedes' screw, 1761-2.
This model was made by George Adams in 1761-2 to demonstrate the working of the hydraulic screw whose invention is traditionally ascribed to Archimedes. Turning the handle at the top makes a ball travel up the helical tube. This model was probably inspired by the French experimental philosopher Abb&eactue; Nollet who wrote
'by means of this ingenious machine a body rises by virtue of the same force that makes it descend. It can easily be seen that if the lower part of the screw is immersed in water the pipe must fill as it turns so that water will flow out at the top.'
The hydraulic screw is still in use in many parts of the world.