ON the 18th of August, 1883, his Holiness, Leo XIII, addressed a letter to Cardinals Antoninus de Luca, Vice-Chancellor, John Baptist Pitra, Librarian of the Holy Roman Church, and Joseph Hergenrother, Prefect of the Vatican Archives. In this important document, the Holy Father, knowing that many of the wide-spread evils of modern society spring not only from the abuse of philosophy and theology, but from a scarcely less fruitful source of error-ignorance or perversion of the truth of history-appeals to all, who love justice and abhor falsehood and misrepresentation, to look for the true story of the past where alone it can be found, in genuine and unadulterated records. He makes a strong protest against the injury done to the Holy See and to the Church at large by those conspirators against truth who, unmindful of the sublime mission of history, degrade the honoured name by connecting it with their idle legends and dishonest statements. To facilitate research and afford increased opportunities for the strictest inquiry, the Papal Archives, containing, among other stores of knowledge, the printed and manuscript treasures of the Vatican Library, are declared to be thrown open to all who are competent to explore such mines of historic wealth. His Holiness invites the most searching investigation, requiring but one condition to be scrupulously observed. Those who shall have access to the new sources of information must, above all things, bear in mind, "that the first duty of the historian is never to venture on a false statement; next, never to shrink from telling the truth; so that his writings may be free from all suspicion of favour or malice." The cordiality with which the Papal Letter has been received by the most intelligent organs of public opinion is very striking, and affords the consolation of finding that the love of truth, deep-seated in our nature, has not yet been eradicated even by those who have conspired against that priceless virtue. Whilst this powerful and high-toned document commanded the respect of all, it was received with admiration and delight by every loyal subject of His Holiness. The Press of every shade of political opinion, clerical, or anti-clerical, pronounced it worthy of the masterhand that penned it. Among the Catholic Prelates it awakened an echo which finds its fitting expression in the vigorous and eloquent pastoral of the late Cardinal Archbishop of Dublin. His Eminence, beyond all doubt, had special grounds of sympathy with the views of the 4th of October, 1883, of the Holy Father. He knew how history has been abused in the case of Ireland, and therefore complains that "if in search of historical information on questions connected with our country, its religion, or its relation to the Apostolic See, we consult books in general circulation, be they epitomes or volumes of pretentious form, we encounter almost in every chapter the most dishonest statements of the facts of history and of the doctrines and discipline of the Catholic Church. Long-exploded calumnies, dressed out anew, as if never refuted; authentic documents distorted, if not falsified; actions in themselves indifferent, if not to all appearances perfectly good, attributed, without a particle of justification, to motives the most criminal. Such are the materials from which is constructed the thing called history; and, on the testimony of such history, our country and our Church have suffered the direst wrongs."