The Kaleidoscope is perhaps the most well known of all optical toys.
Known to the ancient Greeks, the Kaleidoscope was rediscovered and patented
in 1817 by the Scottish scientist Sir David Brewster. The name "Kaleidoscope"
is a combination of three Greek words that mean "an instrument with which
we can see things of beautiful form." After the publication in 1819 of
Brewster's Treatise on the Kaleidoscope, it was only a short while
before the Kaleidoscope became an extremely popular toy.
In its simplest form, the Kaleidoscope is actually a Taleidoscope or
mirrored Kaleidoscope, In a Taleidoscope, three mirrors are taped together.
The mirrors for a hollow triangle and are placed in a long tube. One end
of the tube is open and the other end is covered with a hole in its center.
By looking through the hole at the end of the tube and rotating it, you
could see beautiful changing patterns.