A considerable proportion of the material for the ninth Lecture had been carefully elaborated; but some of it, and the whole of the material for the other three, was in the state just described. This of course added even more to the responsibilities than to the labours of the editor. In the body of the Lectures most scrupulous care has been taken to preserve the author’s _ipsissima verba_, and, wherever possible, the structure and form of his sentences. But from the very necessities of the case, the hand had now and then to be allowed a little more freedom; connecting words, headings, and even here and there a transitional sentence or explanatory clause, had to be added; but in no single instance has a word, phrase or sentence been inserted in the text without warrant from some one part or another of these crowded note-books. With the foot-notes it has been different. One of our earliest and most serious difficulties was to find whence many of the quotations, especially in the ninth Lecture, came. The author’s name was given, but often no clue to the book or chapter. We have been, I think, in every case successful in tracing the quotation to its source. Another difficulty was to connect the various references with the paragraph, sentence or statement, each was meant to prove. This involved a new labour; the sources had to be consulted alike for the purposes of verification and determination of relevance and place. The references, too, in the note-books were often of the briefest, given, as it were, in algebraics, and they had frequently to be expanded and corrected; while the search into the originals led now to the making of excerpts, and now to the discovery of new authorities which it seemed a pity not to use. As a result, the notes to Lecture IX. are mainly the author’s, though all as verified by other hands; but the notes to Lecture X., and in part also XI., are largely the editor’s. This is stated in order that all responsibility for errors and inaccuracies may be laid at the proper door. It seemed to the editor that, while he could do little to make the text what the author would have made it if it had been by his own hand prepared for the press, he was bound, in the region where the state of the MSS. made a discreet use of freedom not only possible but compulsory, to make the book as little unworthy of the scholarship and scrupulous accuracy of the author as it was in his power to do.