A BRIEF DESCRIPTION OF THE LIFE OF HERO OF ALEXANDRIA.

HERO, the Author of this book, had Alexandria of Egypt for his homeland, whence he drew the surname of Alexandrian; his master was Ctesibius the Ascraean, who, as Athenaeus writes in the 4th book of the Deipnosophistae Banquet of the Learned, built a certain hydraulic machine in the time of the second Ptolemy Euergetes, so that, he being his disciple, it can be gathered that he flourished one hundred years before the coming of Christ our Lord. He was a philosopher and mathematician of great name, and he wrote many works, of which part still live, and part have been lost through the long course of years; but yet they are found cited by Eutocius of Ascalon, by Pappus of Alexandria, by Proclus, by the other Hero the Mechanician, author of the treatise on War Machines and Geodesy, by some German Authors, and finally by Peter Ramus, who in his Mathematical Schools did not hesitate to place him on par with Archytas, Leontes, Eudoxus, Aristotle, and Archimedes; and this because (as he says) he joined the Geometry of Plato with the Mechanics of Archimedes, and art with the use of art, which he did principally