The Works of Euclid, Vol. 1

For you, however, this method was not possible in the Latin language; your version would have been too consistent, and often obscure. Following the example of those who preceded you, you used the pronoun ipse, ipsi, ipsius. You are not unaware that I had some hesitation regarding this matter; for those expressions ipsi AT, ipsi ABΓ, I would have preferred these expressions: linea AT, angulus ABΓ, which is somewhat longer.

But since all interpreters of the Greek geometers have long used the same interpolations, you have rightly taken the shortest path to remove the obstacles that occur at every moment, etc.

To signify that two angles sharing the same vertex and a common side are placed upon the same straight line, it is said in Greek: αἱ ἐφεξῆς γωνίαι. Following the example of Commandino, Torelli, etc., I have converted these three Greek words into these two Latin words: deinceps anguli. There are some who have discouraged me from using this word deinceps, because, they said, deinceps never signified the order of things in the Latin language. I did not comply with them. For, when I had read in the Thesaurus linguae latinae of Robert Stephanus, published at Leipzig in the year 1739: duo deinceps reges. Tit. Liv. Funera deinde deinceps duo duxit. Tit. Liv. His perfectis collocatisque alias deinceps rates jungebat. Caes. Morem apud majores hunc epularum fuisse ut deinceps qui occubarent, canerent. Cic., etc., I was certain that Titus Livius, Caesar, and Cicero, etc., accepted the word deinceps in the same sense in which I had accepted it.

As for the French version, it is as consistent with the Greek text as that language permits.

Toward the end of each volume, I have placed a most accurate collation of all the variants of my edition with manuscript 190, and with the Oxford edition; so that with the help of these variant readings, one may, if he wishes, possess a copy of manuscript 190 entirely congruent to this one.

At the end of the final volume, which will be published in this current year 1814, annotations will be added concerning the most significant variant readings and certain passages of Euclid.

I have used the greatest diligence so that my edition might be as emended as possible; the proofs read by me were then read by M. Jannet, as well as by M. Patris, the publisher of my work, and reread again by me. In no proof