Thaumatropes

So I've taken the LEAP and gone in the direction of movement and optical illusions. Now for something you can all try at home. remember sleepy hollow, this clip might refresh you memory. . . .

 

It's basically this:

 

 

When spun looks like this:

 

 



Found out they're called thaumatropes. Wanna know a little more about thaumatropes:

A thaumatrope is a toy that was popular in Victorian times. A disk or card with a picture on each side is attached to two pieces of string. When the strings are twirled quickly between the fingers the two pictures appear to combine into a single image due to persistence of vision.