As the tube is rotated, the tumbling of the coloured objects presents the viewer with varying colours and patterns. Typically there are two rectangular lengthwise mirrors. Setting of the mirrors at 45° creates eight duplicate images of the objects, six at 60°, and four at 90°. A kaleidoscope is a tube of mirrors containing loose, colored objects such as beads and pebbles. The viewer looks in one end and light enters the other end, reflecting off the mirrors. Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. A two-mirror model yields a pattern or patterns isolated against a solid black background, while a three-mirror (closed triangle) model yields a pattern that fills the entire field. Coined in 1817 in English by its inventor Sir David Brewster, the word "kaleidoscope" derives from the Ancient Greek ? ? ? (? ? ) (beauty, beautiful), ? ? ? ? (? ) (form, shape) and -? ? ? ? ? ? (tool for examination), and it literally translates to "observer of beautiful forms. " Kaleidoscopes operate on the principle of multiple reflection, where several mirrors are attached together. Any arbitrary pattern of objects shows up as a beautiful symmetric pattern because of the reflections in the mirrors.
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