See this legally free ebook:

  • Catholic Church and Christian State: a Series of Essays on the Relation of the Church to the Civil Power, Volume 1, translated, with the permission of the author, from the German of Dr. Joseph Hergenröther (London: Burns and Oates, 1876). May be read online, and available in pdf, djvu, epub, kindle/mobi, Daisy, and txt formats, at Internet Archive, with a 2nd copy on this page and a 3rd copy of this page, and at Open Library. Volume I contains the following essays:

I. The Holy See and Civil Allegiance;
II. Doctrine of Infallibility;
III. The Vatican Council;
IV. The Pope and the Bishops;
V. The Syllabus and Modern States;
VI. Fundamental Principles of the Middle Ages;
VII. Civil Rulers and the Holy See; and
VIII. Pope Gregory VII.

Posted on the Memorial of Pope St. Damasus I in the Roman Rite, and on the anniversary of the issuance of the Encyclical “Quas Primas” of Pope Pius XI instituting the Feast of Christ the King. Viva Cristo Rey!