Philo of Byzantium (, Phílōn ho Byzántios, ca. 280 BC – ca. 220 BC), also known as Philo Mechanicus, was a Greek engineer, physicist and writer on mechanics, who lived during the latter half of the 3rd century BC. Although he was from Byzantium he lived most of his life in Alexandria, Egypt. He was probably younger than Ctesibius, though some place him a century earlier. Life and works Philo was the author of a large work, Mechanike syntaxis (Compendium of Mechanics), which contained the following sections: Isagoge (εἰσαγωγή) – an introduction to mathematics Mochlica (μοχλικά) – on general mechanics Limenopoeica (λιμενοποιικά) – on harbour building Belopoeica (βελοποιικά) – on artillery Pneumatica (πνευματικά) – on devices operated by air or water pressure Automatopoeica (αὐτοματοποιητικά) – on mechanical toys and diversions Parasceuastica (παρασκευαστικά) – preparation for sieges Poliorcetica (πολιορκητικά) – on siegecraft Peri Epistolon (περὶ ἐπιστολῶν) – on secret letters The military sections Belopoeica and Poliorcetica are extant in Greek, detailing missiles, the construction of fortresses, provisioning, attack and defence, as are fragments of Isagoge and Automatopoeica (ed. R. Schone, 1893, with German translation in Hermann August Theodor Köchly's Griechische Kriegsschriftsteller, vol. i. 1853; E. A. Rochas d'Aiglun, Poliorcetique des Grecs, 1872). Another portion of the work, on pneumatic engines, has been preserved in the form of a Latin translation (De ingeniis spiritualibus) made from an Arabic version (ed. W. Schmidt, with German translation, in the works of Heron of Alexandria, vol. i., in the Teubner series, 1899; with French translation by Rochas, La Science des philosophes... dans l'antiquité, 1882). Further portions probably survive in a derivative form, incorporated into the works of Vitruvius and of Arabic authors. The Philo line, a geometric construction that can be used to double the cube, is attributed to Philo. A treatise titled De septem mundi miraculis, on the Seven Wonders of the World, is attributed to another Philo of Byzantium, known as "the Paradoxographer", who lived in a much later date, probably the 4th–5th century AD. It is printed in R. Hercher's edition of Aelian (Paris: Firmin Didot, 1858); an English translation by Jean Blackwood is included as an appendix in The Seven Wonders of the World by Michael Ashley (Glasgow: Fontana Paperbacks, 1980). Devices According to recent research, a section of Philo's Pneumatics which so far has been regarded as a later Arabic interpolation, includes the first description of a water mill in