See this legally free ebook:
- The Invitation Heeded: Reasons for a Return to Catholic Unity, by James Kent Stone, S.T.D. [1840-1921] (London: Burns, Oates & Co., 1870). May be read online and available in pdf, epub, mobi and other formats at Internet Archive. A different impression (New York: Catholic Publication Society; Boston: Patrick Donahoe; Baltimore: John Murphy & Co., 1870) is also available at Internet Archive and Internet Archive (2nd copy).
See also the texts on the pages Apologetics and Church and Ecclesiology, as well as the following:
- “Catholic”: An Essential and Exclusive Attribute of the True Church, by Monsignor Thomas John Capel (New York: Wilcox & O’Donnell Co.; D. & J. Sadlier & Co., 1884). Includes, in appendices, the Treatise of St. Cyprian on the Unity of the Church (251 A.D.); the 18th of the Catechetical Instructions of St. Cyril of Jerusalem (347 A.D.); the letter of St. Pacien, Bishop of Barcelona, on the name ‘Catholic’ (373 A.D.); and remarks by the Protestant author Lord Macaulay. May be read online, and available in various formats (pdf, mobi/kindle, epub, etc.) at Internet Archive and Open Library., with a 2nd copy at Internet Archive and Open Library. No Imprimatur, but the author is domestic prelate of Pope Leo XIII, and its content is Catholic.
- The Catholic Church the True Church of the Bible, by Very Rev. C. J. O’Connell (St. Louis, MO, Freiburg (Baden), London: B. Herder, 1913). With Imprimatur. Available in various formats (pdf, epub, mobi/kindle, etc.) at Internet Archive and Open Library; and also available at HathiTrust Digital Library.
- The Catholic Controversy, by Saint Francis de Sales, translated by Rev. Henry Benedict Mackey, O.S.B. (London: Burns and Oates, 1886). May be read online on this page of Good Catholic Books. The 3rd revised and augmented edition, with an excellent translator’s preface (New York, Cincinnati, Chicago: Benziger Brothers; London: Burns and Oates, 1909) (Library of St. Francis De Sales, Volume III) is available in various formats at Internet Archive.
- Catholic Doctrine as Defined by the Council of Trent: Expounded in a Series of Conferences Delivered in Geneva, Proposed as a Means of Reuniting All Christians, by Adrien Nampon, translated from the French, with the approbation of the author, by a member of the University of Oxford (Philaelphia: Peter F. Cunningham & Son, 1869). With the approbation of various bishops. Available in various formats at Internet Archive, with a second copy at Internet Archive and Open Library.
Posted for the Week of Prayer for Christian Unity, on the Memorial of Saint Francis de Sales (in the Latin and Syriac sui iuris churches) and of the Blessed Martyrs of Pratulin, in earnest prayer that our separated brethren may be converted from schism and heresy to divine and Catholic truth. For other texts and ebooks, you may access the List of Free eBooks (Arranged by Title), the List of Free eBooks (Grouped by Subject), the List of Worth-It Catholic Books & eBooks, and the main page of the Catholic eBooks Project.