Hero (or Heron) of Alexandria was among the first true technologists of antiquity. He was a mathematician, mechanic and taught technical subjects in the prestigious Museum of Alexandria, probably in the mid-first century B.C. His biographical events are still the object of discussion.
His work places him among the most influential exponents of the Hellenistic scientific tradition. Hero, not only focused on studying the practical aspect of the inventions, but he also deepened the theoretical part. He completed numerous significant theoretical contributions, elaborated the design of his machines, and he deeply studied the works of Archimedes and Euclid. Regarding the latter, he wrote the Commentaries to Euclid's Elements.
The corpus of his work is vast. He dealt with geometry, artillery, catoptrics, pneumatics, and mechanics. As for his writings on mechanics, the treatise Automata stands out. This book had a great impact in the Renaissance period, during which it was studied by philosophers and technologists, such as B. Buontalenti (1531 – 1608) and G. Aleotti (1546 – 1636).
To our best knowledge, the first time that the text was translated into a Western language was with the edition of Bernardino Baldi in 1589. Baldi was a mathematician from Urbino and contributed to the translation of the Automatainto Italian from the Greek original text. It was a project initiated by his teacher, F. Commandino (1509 – 1575), in which G. Contarini (1536 – 1595) also participated. This is a critical edition, accompanied by explanatory notes, printed in Venice.
The dedication is to Giacomo Contarini, a Venetian nobleman. This is followed by a Discorso di chi traduce(speech of the translator). The treatise is divided into two books, both with preface by Hero. The first book is entitled Delle macchine se moventi and deals primarily with constructing of an altar that moves along a variable path. In the first book, and the second, it emerges how the construction of automata involves all kinds of mechanical knowledge and a complex variety of technical abilities. It is worth noting how the descriptions of his devices reveal the use of hydraulic elements and principles. A series of fifteen illustrations complete the text. The second volume – Delle se moventi stabili – shows how to build a macchina se movente stabile, in particular a fixed theater where the facts of the fable of Nauplio are represented. As in the first book, the explanation is accompanied by seven illustrations. At the end of the treatise are proposed annotations by Baldi, mostly of philological character to the translated text.
The treatise Automata, following the translation of Baldi, was the subject of a further edition with Greek and Latin text at the end of the seventeenth century (1693), thanks to the work of the French diplomatic, writer and scientist Melchisédech Thévenot (1620 – 1692) (Veterum mathematicorum Athenaei, Apollodori, Philonis, Bitonis, Heronis et aliorum opera Graece et Latine pleraque nunc primum edita). It seems necessary to wait for the second half of the nineteenth century for an edition translated into Western languages. It was, in fact, in 1881 that the civil engineer Victor Prou (1831 – 1884) translated the Automata into French (Les théâtres d᾿automates en Grèce au IIe siècle avant l᾿ère chrétienne d᾿après les ΑΥΤΟΜΑΤΟΠΟΙΙΚΑ d᾿Héron d᾿Alexandrie) and, sometime later, Wilhelm Schmidt (1862 – 1905) published the Opera omnia of Hero in 1899, that includes the Greek text of Automata (Heronis Alexandrini opera quae supersunt omnia) and a German translation. The English translation only appeared recently with Susan Murphy's work of 1995 (Heron of Alexandria’s On Automaton-Making).
Hero’s work also circulated in the Iberian Peninsula. However, Baldi's version in Italian is present in the National Library of Spain (BNE) and in the Library of the University of Santiago de Compostela.