HERO, the name of two celebrated Greek mathematicians; the one called the old, and the other the young, Hero. The younger was a diſciple of Cteſibius. They are known by two works tranſlated into Latin by Barochius; Spiralium liber, by Hero ſenior; and Traſlat. artis et machin. militar. by Hero junior. They flouriſhed about 130 and 100 B. C.