i think they work by turning the knob at the end. there is a tub of beads there and it makes a lovely image from the reflect of the mirrors. this is probbly wrong.
It was invented in the 19th century by Sir David Brewster. He named it from two Greek words meaning 'beautiful' and 'form', and added the word scope to show that it was something that you look...
kaleidoscope is a thing/object which works on the principle of multiple reflections. the three plain mirrors reflect light that,s why we can see paterns.
A kaleidoscope doesn't work in a diagram, it works with light. Basically the light bounces around inside, and then hits your eye, but because of all the mirrors, it comes out with some cool...