<p style='text-align: justify;'>Maxwell had a lifelong interest in zoetropes. They provided moving images for amusement and for illustrating scientific phenomena. To improve the moving image, Maxwell replaced the slits by convex lenses which focussed the images on the axis of the Zoetrope and offered a wider field of view. Maxwell set this as a Tripos examination problem when he was an external examiner for the Mathematical Tripos in 1869.</p>