TITLE: Tractatus de Sphaera Mundi
AUTHOR: Johannes de Sacrobosco [John Halifax of Holywood]
DESCRIPTION: A fitting end to this volume, this map is from a treatise
that is often cited as atypical of the medieval period because it is derived
entirely from the writings of earlier scholars, leaning especially on Ptolemy's
astronomical work the Almagest. However, even without the addition
of the new discoveries, it achieved a great popularity that lasted well
through the Renaissance, for after the invention of printing no fewer than
65 editions succeeded each other in rapid order and occupied the attentions
of the foremost scientific printers of the time. Its popularity may be explained
not only by its dependence on established authority, but on its slight bulk
and the simplicity to which elaborate theories were reduced. Its four chapters
deal with the terrestrial globe, circles, the movements of the stars and
with the planets. It was doubtless this brevity which recommended it to
seafaring folk, for it was known to have been one of the standard text books
of the Portuguese seamen during their great age of exploration.
Johannes de Sacrobosco, latinized for John Halifax of Holywood, a teacher
of mathematics and astronomy at the University of Paris during the 13th
century. He was probably from Yorkshire, England, educated at Oxford, and
migrated to Paris in 1221, where he compiled his Tractatus de Sphaera
Mundi (a manual or textbook for beginners in the study of astronomy
and cosmography, illustrated by a world map and diagrams and Sacrobosco's
Compotus, Quadrans, Algorismus, Cautelæ ) Twenty-five editions
of this work appeared prior to 1500, and a further 40 editions up to 1647,
even though no original work was included, nor added to the reissues (even
though such items as his earth-centered diagrams of the solar system were
superceded by the Copernican theory and new geographical discoveries outdated
his map). This map, therefore had one of the widest distributions and circulation
among students during these two-three centuries.
As can be seen in this woodcut printed example, its is a simple map based
upon the construct of Ambrosius Aurelius Macrobius (ca. 410, Slide
#201 ) and containing a hemispherical world divided into seven climatic
zones, a system devised by the Greeks and Ptolemy. This map shows the uninhabitable
Southern Frigid Zone (at the top, the map has a South-orientation ); the
unexplored Southern Temperate Zone which is habitable; a central Hot Zone
which is not habitable; the Northern Temperate Zone where Europe, Asia and
Africa occupy the known world; and the Northern Frigid Zone which is also
Therefore, Sacrobosco is one of the best representations of the entire medieval
period, since his influence spans both the early and later periods. He lived
and worked in the early medieval period of the 13th century; and his maps
continued to be reproduced in large quantity for another four centuries,
no small feat for such a simple cartographic scheme.
LOCATION: New York Public Library
*Bagrow, L., History of Cartography, p. 44.
Beazley, C., The Dawn of Modern Geography, Volume II, pp. 573-75.
*Bricker, C., Landmarks of Mapmaking, pp. 14, 60.
Brown, L.A., The Story of Maps, pp. 98, 152, 198-201.
*Brown, L.A., TheWorld Encompassed, no. 13.
*Harley, J.B., The History of Cartography, Volume I, pp. 306, 307, 314,
Kimble, G.H.T., Geography in the Middle Ages, p. 9.
*Tooley, R., Maps and Mapmakers, p. 49