OLOUR. 25 really be at more than one part of the circle at a time, though the appearance is so different. W N E S F I H O D R O L G T Or if we print on a card the letters as here arranged, seven letters on each side (the heads of the letters on the one side being towards the opposite edge of the… … of the card. Or a mouse can be drawn on one side of a card, and a cage on the other, when the card is rotated the mouse will appear to be in the cage.* * These are called “ Thaumatropes,” from the Greek tliaiima , a wonder, and trepo, to turn. c
Light · Color · Optical illusions · Optics
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