CHAPTER II

ROGER BACON. _Fr. Rogeri Bacon Opera Quaedam Hactenus Inedita._

J. S. Brewster. London, 1859.

_The Opus Majus of Roger Bacon_, edited with an introduction and analytical table by John Henry Bridges. Oxford, 1897–1900.

_Letter concerning the marvelous power of art and of nature, and concerning the nullity of magic._ Translated from the Latin by Tenney L. Davis. Easton, Pa., 1923.

_Part of the Opus Tertium_ of Roger Bacon, including a fragment now printed for the first time, edited by A. G. Little. Aberdeen, 1912.

PIERRE MAURICE MARIE DUHEM. _Le Système du monde_, histoire des doctrines cosmologiques de Platon à Copernic. Paris, 1913–1917.

WITELO. _Vitellionis Turingopoloni Libri X._

Basel, 1572.

_Vitellionis Mathematici Doctissimi_ Περὶ Ὀπτικῆς. Nuremberg, 1535.