To understand this amazing period and the spirit which dictated its voluminous, though now forgotten, masterpieces, to analyze it, even to its barbarisms, we need only examine the Constitutions of the University of Paris and the extraordinary scheme of instruction that then obtained. Theology was taught under two faculties--that of Theology properly so called, and that of Canon Law. The faculty of Theology, again, had three sections--Scholastic, Canonical, and Mystic. It would be wearisome to give an account of the attributes of each section of the science, since one only, namely, Mystic, is the subject of this _Etude_. Mystical Theology included the whole of Divine Revelation and the elucidation of the Mysteries. And this branch of ancient theology has been secretly preserved with reverence even to our own day; Jacob Boehm, Swendenborg, Martinez Pasqualis, Saint-Martin, Molinos, Madame Guyon, Madame Bourignon, and Madame Krudener, the extensive sect of the Ecstatics, and that of the Illuminati, have at different periods duly treasured the doctrines of this science, of which the aim is indeed truly startling and portentous. In Doctor Sigier’s day, as in our own, man has striven to gain wings to fly into the sanctuary where God hides from our gaze. This digression was necessary to give a clue to the scene at which the old man and the youth from the island under Notre-Dame had come to be audience; it will also protect this narrative from all blame on the score of falsehood and hyperbole, of which certain persons of hasty judgment might perhaps suspect me. Doctor Sigier was a tall man in the prime of life. His face, rescued from oblivion by the archives of the University, had singular analogies with that of Mirabeau. It was stamped with the seal of fierce, swift, and terrible eloquence. But the Doctor bore on his brow the expression of religious faith that his modern double had not. His voice, too, was of persuasive sweetness, with a clear and pleasing ring in it.