Leaf from De Sphaera.

A leaf from Joannes de Sacrobosco's De Sphaera, illustrated with astronomical figures in wood block.
Born at the end from XIIe century, Joannes de Sacrobosco studied in Oxford, arrives in Paris about 1220.
His book De Sphaera is divided in four chapters and is founded on the astronomy of Ptolemy with accompanying notes by the Arabs: Sacrobosco is one of the first doctors of the Middle Ages to use the astronomical writings of the Arabs.
De Sphaera is adopted at once by the university of Paris, and soon by all those of the Western world. Abundantly copied, it was then the first book of astronomy printed, since 1472, in Ferrare. One counts on the whole not less than 65 editions. Thus, De Sphaera was the handbook of initiation to astronomy for all the students of the beginning of XIIIe at the end of XVIe century.
And in full XVIIe century, after the publication of revolutionibus of Nicolas Copernic (1543), which made null and void the cosmology of Ptolemy, and that of Astronomia nova of Kepler (1609), which eliminated the circles from the astronomical practice, the Sphere of Sacrobosco is still published and taught in the schools of Germany, France and the Netherlands. However, this treaty is very short and rather poor of ideas.