††The kaleidoscope is an optical toy which was invented in 1816 by Sir David Brewster. A kaleidoscope is a triangular tube containing up to three angled mirrors. At one end is an eyepiece, and at the other end small pieces of coloured glass and coloured foil are trapped between clear glass panels. This coloured glass and foil is able to move freely when the tube is shaken. The pieces are reflected several times by the mirrors to form a circular pattern which can be seen by the user. By shaking or rotating the tube, the pattern can be made to change.
