A kaleidoscope is a cylinder with mirrors containing loose, colored objects such as beads or pebbles and bits of glass. As the viewer looks into one end, light entering the other creates a colorful pattern, due to the reflection off of the mirrors. Coined in 1817 by Scottish inventor Sir David Brewster, "kaleidoscope" is derived from the Ancient Greek καλός (kalos), "beautiful, beauty", εἶδος (eidos), "that which is seen: form, shape" and σκοπέω (skopeō), "to look to, to examine", hence "observer of beautiful forms."
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