An advertising card, featuring the "bicycle wheels" or "strobic circles" illusion. The front of the card has a set of blue concentric circles and a set of red concentric circles, as well as the instructions for the illusion. The back of the card has more advertising information.
PEARS' Bicycle Wheels
OR STROBIC CIRCLES.
GIVE this a rapid continuous twisting motion, thus [curved arrow icon] when each circle will separately revolve on its own axis.
