This Source Book explores a millennium of European scientific thought accompanied by critical commentary and annotation; nearly half the selections appear for the first time in the vernacular. Representing "science" in the medieval sense, selections include alchemy, astrology, logic, and theology as well as mathematics, physics, and biology.

Samuel Pepys (1633-1703) was a student of Magdalene College, Cambridge, and bequeathed his personal library of 3000 volumes to the College on condition that the contents remained intact and unaltered; they remain there, in his original bookcases, to this day. In the early twentieth century, a project to produce a complete catalogue was begun, and four volumes were published between 1914 and 1940. Volume 3 lists 51 volumes of medieval manuscripts, some of them consisting of several items bound together. The author, the outstanding palaeographer and prolific writer of catalogues M. R. James, remarks on the almost total absence of Latin liturgical and theological manuscripts, and calls attention to the historical, literary and scientific writings in English and French, several picture-books, an interesting 'scrapbook' and a unique copybook from 1400 included in Pepys' collection. This book continues to be a valuable resource for medievalists and Pepys scholars alike.