Tom blok Photo collection by Th.Schiöler Spiral scoops, screws and the chain pump The Archimedean screw Photo 153
The Archimedean screw
Gul streg
Photo 511 x 506 pixels, 43,6 K
 
A screw near Cairo
It is hard work to turn an Archimedean screw. Even more exhausting than pedaling a bicycle. On a bicycle, you are only pressing downwards, but for the screw, it must be pushed all the way round. It needs at least twice as much power as a bicycle.
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