To correct this text, Father Vercellone has directed his studies, and in the volumes before us the fruit of his labours has been given to the world. How arduous these labours have been, and what confidence we may feel in his selection of readings, will best be learned from an enumeration of the sources whence, with incredible pains, he has drawn the information required for the execution of his design. These sources may be classed under three heads: Vatican papers, MSS. codices, and printed books. As to the first class, Pius IX. has assisted Father Vercellone by placing at his disposal the treasures stored up in the Vatican archives. Hence, our author has been enabled to examine, 1^o, the documents of the corrections proposed and adopted by the congregation appointed to edit the Vulgate under Saint Pius V. in 1569, which documents he has compared with the writings of Cardinal Serleto, who had a great share in making those corrections; 2^o, the documents concerning the corrections proposed or adopted in a similar congregation, under Sixtus V. in 1588 and 1589; 3^o, the Sixtine edition of 1590; 4, notes of the corrections discussed in the congregations appointed under Gregory XIV. and Clement VIII. to free the Sixtine edition, from its many mistakes of the press; 5^o, the readings proposed by the learned Angelo Rocca; 6^o, the annotations of Cardinal Toleto, preserved in the Vatican; and 7^o, the Clementine edition of 1592. As to the MSS., our author has confined himself to a few, but these few are of the highest authority. Of the twenty consulted by him, the remarkable Florentine Codex of Monte Amiata is deservedly placed first. Saint Pius V. had caused the Benedictines of Florence to collate 12 codices, and the archivist of Monte Cassino to examine 24 others. The notes of both these undertakings are still in the Vatican, and have been of great assistance to Father Vercellone. Of printed editions prior to the Clementine of 1590, the author has consulted more than 80, many of them the work of excellent critical scholars. To these are to be added liturgical books, for example, the works of the B. Cardinal Thomasi, the Mozarabic liturgy, edited by Cardinal Lorenzana, and the Roman liturgy. To these again we must add, the Latin Fathers, whose works give much valuable assistance in determining the text of the Vulgate. Finally, F. Vercellone has carefully studied the commentaries of Hesychius, Rodolphus, Bruno of Asti, and the publications of Cardinals Mai and Pitra. This is the labour of a life, and few indeed could be found with the qualities required to undertake it and bring it to a happy termination.