Complete Works of Euclid, Vol. 2 (Elements V-IX)

PREFACE.

In editing those books of the Elements which are contained in this volume, I have taken as a foundation the codices P, B, F, and V, regarding which the brief notice that I provided in Vol. I, pp. VIII—IX, should be consulted; H. Menge collated the Bodleian codex B for books VIII—IX¹). I was able to use the Parisinus 2466 (p) only in book VII, and it is not of great importance. But since the Laurentian codex F, the best of all the Theonine codices, was lacking from VII, 12, p. 216, 20 to IX, 15, p. 378, 6 — for it is apparent that that part of the codex, which I have designated by the letter $φ$, is entirely useless, a matter which I shall discuss more fully in the prolegomena of volume IV — and since the Bononian codex b (see vol. I, p. IX) did not differ greatly from the Florentine in this part, I collated it this year at Bologna from VII, 13 to IX, 15, and I shall note the discrepancy in readings at this place. To supplement the critical apparatus in books VIII—IX, I also collated the Parisinus Gr. 2344 (q), a parchment manuscript of the 12th century, which I easily obtained through the mediation of the Prefect of the Royal Library of Copenhagen and the liberality of the Parisian librarian Léopold Delisle, so that it might be transmitted to Copenhagen.

1. In these two books, from VIII, 17, regarding the letter $ν$ which they call ephelkystikon, whether omitted or added, nothing had been noted in the collation of B.