In the course of researches among the libraries of Scotland and Italy, of England and France, of Spain and Germany, I have received much kindness from the learned men who direct these institutions. I therefore gladly avail myself of this opportunity to express my thanks in general to all those who have so kindly come to my help, and in particular to Signor Comm. G. Biagi, and Signor Prof. E. Rostagno of the Laurentian Library; to Signore L. Licini of the Riccardian Library; to the Rev. Padre Ehrle of the Vatican Library; to Signor Cav. Giorgi, and the Conte Passerini of the Casanatense; to Signor Prof. Menghini of the Vittorio Emanuele Library, Rome; and to Signor Comm. Cugnoni of the Chigi Library. I am also much indebted to the kindness of Professor R. Foerster of Breslau; of Mr. W. M. Lindsay, Fellow of Jesus College, Oxford, and the Rev. R. Langton Douglas of New College, who have furnished me with valuable notes from the libraries of that university, and, not least of all, to the interest taken in my work by Mr. Charles Godfrey Leland, who has been good enough to read it in manuscript, and to favour me with curious material and valuable suggestions. If the result of my studies should prove somewhat disappointing to the reader, I can but plead the excuse with which Pliny furnishes me, it is one having peculiar application to such a task as is here attempted: ‘Res ardua,’ he says, ‘vetustis novitatem dare, novis auctoritatem, obsoletis nitorem, obscuris lucem, fastiditis gratiam, dubiis fidem, omnibus vero naturam, et naturae suae omnia.’ 17 VIA MONTEBELLO, FLORENCE, _November 17th, 1896_. CONTENTS PAGE CHAPTER I State of Scotland in the twelfth century—Necessity of foreign travel to scholars bred there—Michael Scot: his Nation and Birthplace.—The account given by Boece, how far it is to be believed—The date of Scot’s birth and nature of his first studies—Scot at Paris: his growing fame, and the degrees he won in that school—Probability that further study at Bologna formed the introduction to his life in the south, 1 CHAPTER II The position held by Scot at the Court of Sicily—His service under the Clerk Register, who seems to have been the same as Philip of Tripoli—Scot appointed tutor to Frederick II.—Advantages of such a position—He teaches the Prince mathematics and acts as Court Astrologer—Publication of the _Astronomia_ and _Liber Introductorius_—Frederick’s marriage—Scot produces the _Physionomia_ and presents it on this occasion—Account of this the most popular of his books, and of the sources from which it was derived—Scot quits Sicily for Spain, 18 CHAPTER III