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they have always agreed with the Sun. As to the Printing of the *Figure* of my New Watch, I shall defer that yet a while: but it shall in time appear with all the Demonstrations thereof, together with a *Treatise of Pendulums*, written by me some days since, which is of a very subtile Speculation.

*The Character, lately published beyond the Seas, of an Eminent person, not long since dead at*Tholouse,

*where he was a Councellor of Parliament.*

It is the deservedly famous *Monsieur* *de Fermat*, who was, (saith the Author of the Letter) one of the most Excellent Men of this Age, a *Genius* so universal, and of so vast an extent, that if very knowing and learned Men had not given testimony of his extraordinary merit, what with truth can be said of him, would hardly be believed. He entertained a constant correspondence with many of the most Illustrious Mathematicians of *Europe*, and did excel in all the parts of Mathematical Science: a Testimony whereof he hath left behind him in the following Books.

A Method for the Quadrature of *Parabola's* of all degrees.

A Book *De Maximis & Minimis*, which serveth not only for the determination of Problems of *Plains* and *Solids*, but also for the invention of *Tangents* and *Curve Lines*, and of the *Centres* of Gravity in Solids; and likewise for Numerical Questions.

An Introduction to the Doctrine of *Plains* and *Solids*, which is an *Analytical* Treatise, concerning the solution of *Plains* and *Solids*, which has been seen (as the Advertiser affirms) before Monsieur *Des Cartes* had publish'd any thing upon this Subject.

A Treatise *De Contactibus Sphæricis*, where he hath demonstrated in *Solids*, what Mr. *Viet*, Master of Requests, had but demonstrated in *Plains*.

Another Treatise, wherein he establisheth and demonstrateth the two Books of *Apollonius Pergæus*, of *Plains*.

And a General Method for the dimension of *Curve Lines*, &c. Besides, having a perfect knowledge in Antiquity, he was consulted from all parts upon the difficulties that did emerge therein: he hath explained abundance of obscure places, that are

found