| In the Zoetrope, a series of images is viewed, one after
another, though slits in a drum. The vertical viewing slits are in the
upper edges of the drum, and the pictures are placed on a band of paper
inside the lower portion of the drum. The observer looks through the slits
as they pass by and sees the pictures that are diagonally opposite.
The Zoetrope is sometimes called "The Wheel of Life". This example is in the Wileman collection of devices for optical recreations at the North Carolina School of Science and Mathematics at Durham.
A similar device was sold by Max Kohl of Chemnitz for 16.50 Marks (about $4.00) in 1900.
uses essentially the same geometry, except that the vertical slit is
replaced by an internal, multiple-sided mirror that is used to view