Kaleidoscope
A kaleidoscope consists of a tube containing mirrors and pieces of coloured glass or paper, whose reflections produce changing patterns when the tube is rotated.
"Kaleidoscope" is derived from the Ancient Greek word (kalos) "beautiful, beauty", (eidos) "that which is seen: form, shape" and (skopeĊ), "to look to, to examine", hence "observation of beautiful forms.