Four leaves of colored, interactive anatomical flaps appear throughout this popular anatomical textbook, which recapitulates the combination of art, engineering and anatomy in Galileo’s world. As a pop-up flap book, it represents both the mechanical approach to the body and an engineering approach to the printed book. Its colored illustrations show the persistence of art in anatomical texts. And it was heavily used; in addition to the lab-stains and marginal annotations, the OU copy contains 84 pages of hand-written student notes.