Armillary sphere, 1535.
© Science Museum / Science & Society Picture Library
Plate showing a diagram of a Ptolemaic armillary sphere, a demonstrative instrument, to illustrate the Earth centred model of the universe. It is taken from 'Margarita Philosophica' (Pearl of Wisdom), 1535 edition (p 546), written by the medieval philosopher, Gregor Reisch (1467-1525). This encyclopaedic work contains commentaries on the subjects of astronomy, geometry, anatomy and geography.