Waterfall (M. C. Escher)
Waterfall (Waterval) is a lithograph print by the Dutch artist M. C. Escher which was first printed in October, 1961. It shows an apparent paradox where water from the base of a waterfall appears to run downhill along the water path before reaching the top of the waterfall.
While most two-dimensional artists use relative proportions to create an illusion of depth, Escher here and elsewhere uses conflicting proportions to create a visual paradox. The waterfall's leat has the structure of two Penrose triangles. A Penrose triangle is an impossible object designed by Lionel Penrose and his son Roger Penrose, and (independently) by Oscar Reutersvärd.
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