Did you know that Dr. Seuss wrote Green Eggs & Ham on a dare that he create a story out of just 50 different words? That and more fun facts are featured in this less than two-minute video from the University of California’s Fig. 1 video series about the beloved mid-century children’s author Theodor Geisel, better known as Dr. Seuss. Watch how picture books were made at the time (different shades of the same color were denoted with percentages, so the printer knew how dark they should be), and how fiercely dedicated to his aesthetic Geisel was (one note on a draft reads “White inside the hambone always”). The video is maddeningly short–all we can do is hope there’s more where that came from.