When observers approach or move away from the image with fixing their eyes on the central cross, one ring appears to rotate clockwise while the other one to rotate counterclockwise.pic.twitter.com/X7Wh5Hp9aN
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Ah, I don't remember seeing that one. Very nice. Actually, I was thinking of "A tire" from this page on your website: http://www.ritsumei.ac.jp/~akitaoka/rotate-e.html …pic.twitter.com/Z2VVwWOloS
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