The elements of Euclid, explained and demonstrated in a new and most easie method with the uses of each proposition in all the parts of the mathematicks / by Claude Francois Milliet D'Chales, a Jesuit ; done out of French, corrected and augmented, and illustrated with nine copper plates, and the effigies of Euclid, by Reeve Williams ...

THE Authors Preface TO THE READER

HAving long since observed, that the greatest part of those that learn Euclid's Elements, are very often dissatisfied therewith, because they know not the use of Propositions so inconsi∣derable in appearance; and yet so diffi∣cult: I thought it might be to good pur∣pose, not only to make them as easie as possible, but also to add some Ʋses after each Proposition, to shew how they are applicable to Practice. And this hath obliged me to change some of the De∣mnostrations, which I looked upon to be too troublesome, and above the usual

reach of beginners, and to substitute others more intelligible. For this cause, I have Demonstrated the Fifth Book after a method much more clear than that, that makes use of equimultiples. I have not given all the Ʋses of the Propositions, for that would have made it necessary to recite all the Mathematicks, and would have made the Book too big, and too hard. Wherefore, I have only made choice of some of the plainest and easiest to conceive, I would not have you to stand too much upon them, nor make it your study to understand them perfectly because they depend upon other princi∣ples besides, for which Reason I have distinguished them with the Italick Letter. This is the design of this small Treatise, which I willingly publish in a time when the Mathematicks are more than ever studied.

Milliet D'chales