second expounded the system of Avicenna himself, and the third contained the more esoteric and occult doctrines of natural philosophy.[89] Of these the first alone had reached the Western schools. It is plain then that until Michael Scot took the work in hand Toledo had not completed the Latin version of Avicenna by translating that part of the _Alchefâ_ which concerned the Natural History of Animals. The _Abbreviatio Avicennae_ thus came to supply the defect and to crown the labours of the ancient college of translators. This place of honour is actually given to it in the Vatican manuscript just referred to, where it follows the _De generatione Lapidum_, and forms the fitting close of that remarkable series and volume. Thus, while the _De Animalibus ad Caesarem_ connects itself with the _Physionomia_, and with Scot’s past life in Sicily, the _Abbreviatio Avicennae_ joins him closely and in a very remarkable way with the whole tradition of the Toledo school, of which, by this translation, he at once became not the least distinguished member. [Illustration: FROM M.S. FONDO VATICANO 4428, p. 158, _recto_] The authority of this manuscript, now perhaps for the first time appealed to, is sufficient not only to determine the relation of Scot’s work to that of the earlier Toledan school, but even, by a most fortunate circumstance, enables us to feel sure of the exact date when the translation of the _Abbreviatio_ was made. For the colophon to the Vatican manuscript, brief as it is, contains in one line a fact of the utmost interest and importance to all students of the life of Scot. It is as follows: ‘Explicit anno Domini mºcºcºx.’[90] The researches of Jourdain had the merit of making public two colophons from the manuscripts of Paris, containing the date of another and later work of Scot,[91] but since the days of that savant no further addition of this valuable kind has been made to our knowledge of the philosopher’s life. The date just cited from the Vatican copy of the _Abbreviatio_ shows, however, that further inquiry in this direction need not be abandoned as useless. We now know accurately the time when this version was completed, and find the date to be such as accords exactly with our idea that Scot must have quitted Sicily soon after the marriage of Frederick; for the year 1210 may be taken as a fixed point determining the time when he first became definitely connected with the Toledo school. It will be remembered that we anticipated this result of research so far as to use it in our attempt to conjecture the date of Scot’s birth.[92]