Visual Illusion Small 320×73 Medium 640×146 Large 1024×234 Download Tiff Original 2400×549 | (1.3 MB) Description Print this figure on a sheet of paper and then give it a slight twirling motion as if you were swirling water around in a dish. The cog-wheels will appear to revolve slowly, while the other wheels turn rapidly in the opposite direction. Keywords Visual illusion Galleries Visual Illusions Source: Arthur Mee and Holland Thompson, eds. The Book of Knowledge (New York, NY: The Grolier Society, 1912)
