An animation of two interwoven waterways is presented. Each waterway forms a complete circuit. Geometry and viewpoint combine to provide the illusion that the waterways are continuously flowing downhill and that each is in front of the other. Admirers of M.C. Escher may notice some similarity between this animation and his drawing entitled "Waterfall."
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Robert Rudd is an engineer at BF Goodrich Aerospace in Vergennes, Vermont. He received bachelors and masters degrees in mechanical engineering from Rensselaer Polytechnic Institute in Troy, New York, and has worked at the Unisys and Singer Corporations.