Tom blok Photo collection by Th.Schiöler Spiral scoops, screws and the chain pump Spiral scoops Photo 147
Spiral scoops
Gul streg
Photo 511 x 506 pixels, 43,6 K
 
Flow from a scoop-sâqiya
The outlet from the scoop-wheel ought to be large, so as to reduce the hydraulic resistance. The construction of this water-lifting device is so old that all technical problems have been solved. It is still popular and there must be more than 400,000 in the Delta.
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