rson, not
long since dead at _Tholouse_, where he was a Councellor of Parliament._

It is the deservedly famous _Mounsieur 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 Sphaericis_, 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 Pergaeus_, 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 emerg therein: he hath explained abundance
of obscure places, that are {16} found in the Antients. There have been
lately printed some of his Observations upon _Athenaeus_; and he that hath
interpreted _Benedetto Castelli_, of the Measure of running waters, hath
thence inserted in his Work a very handsome one upon an Epistle of
_Synesius_, which was so difficult, that the Jesuit _Petavius_, who hath
commented upon this Author, acknowledges, that he could not understand it.

He hath also made many Observations upon _Theon of Smyrne_, and upon other
Antient Authors: but most part of them are not found but scattered in his
Epistles, because he did not write much upon these kinds of Subjects, but
to satisfie the curiosity of his friends.

All these Mathematical Works, and all