Little Rhodia pads are perfect for flip animation, don’t you think? The N° 10 is 2×3″ and the Nº 11 is 3×4″. The graph ruling helps the artist guide the drawing from one page to the next.
The first flip book appeared in September, 1868, when it was patented by John Barnes Linnett under the name kineograph (“moving picture”). A flip book is a book with a series of pictures that vary gradually from one page to the next, so that when the pages are turned rapidly, the pictures appear to animate by simulating motion or some other change. (Per Wiki)
Want to make your own flip book? Instructions can be found on Wired how-to.