HERON (ca.75?)

    There has been much dispute as to the exact time that he lived, which has been variously estimated from 150 B.C. to A.D.250.  More recently, he has been placed in the second half of the first century A.D.  His works on mathematical and physical subjects are so numerous and varied that it is customary to describe him as an encyclopedic writer in these fields  There are reasons to suppose he was an Egyptian with Greek training.  At any rate, his writings, which so often aim at practical utility rather than theoretical completeness, show a curious blend of the Greek and the Oriental.  He did much to furnish a scientific foundation for engineering and land surveying.

    Fourteen or so treatises by Heron, some evkdently considerably edited, have come down to us, and there are references to additional lost works.
Heron's works may be divided onto two classes, the geometric and the mechanjcal.  The geometric works deal largely with problems on mensuration, and the mechaniccal ones with descriptions of ingenious mechanical devices.
    The most important of Heron's geometrical works is his Metrica,sritten in three books and discovered in Constantinople by R. Schone, as recently as 1896.