abstract: In a classic article, Marie Boas traced the career and influence of Hero's Pneumatica through the sixteenth and seventeenth centuries, crediting the Pneumatica with the revival of ancient corpuscularism in the seventeenth century and suggesting that this was a crucial part of the inspiration for the mechanical philosophy. But Hero's influence on early mechanics extended beyond the Pneumatica, since in the course of the sixteenth century both the Automata and Belopoiica were also translated and printed. And although Hero's Mechanics was unknown in the sixteenth century, his treatment there of the five powers or simple machines came to be known through Pappus' Mathematical Collection and adopted by most mechanical writers after Guidobaldo del Monte. This paper will sketch the reception of Hero's works and examine their influence on mechanical theory and practice in the sixteenth century.