Philo was the author of a large work, the
Syntaxis (), which contained the following sections: • Isagoge (; general mathematics) • Mochlica (; mechanics) • Limenopoeica () • Belopoeica ) • Pneumatica () • Automatopoeica (; mechanical toys and diversions) • Parasceuastica (; for
sieges) • Poliorcetica () • Peri Epistolon (; on coding and hidden letters for military use) 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 () of an Arabic translation (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.
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 history, placing the invention of the water mill in the mid-third century BC by the Greeks. Philo's works also contain the oldest known application of a chain drive in a
repeating crossbow. Two flat-linked chains were connected to a
windlass, which by winding back and forth would automatically fire the machine's arrows until its magazine was empty. Philo also was the first to describe a
gimbal: an eight-sided
ink pot that could be turned any way without spilling and expose the ink on top. This was done by the suspension of the inkwell at the centre, which was mounted on a series of concentric metal rings which remained stationary no matter which way the pot turns. In his
Pneumatics (chapter 31) Philo describes an
escapement mechanism, the earliest known, as part of a
washstand. He is also credited with the construction of the first
thermoscope (or Philo thermometer), an early version of the thermometer.
Mathematics In mathematics, Philo tackled the problem of
doubling the cube. The doubling of the cube was necessitated by the following problem: given a catapult, construct a second catapult that is capable of firing a projectile twice as heavy as the projectile of the first catapult. His solution was to find the point of intersection of a rectangular
hyperbola and a
circle, a solution that is similar to the solution given by
Hero of Alexandria several centuries later.
Apocrypha A treatise titled "
Seven Wonders of the World" () is sometimes attributed to this Philo but more probably belongs to a different Philo of Byzantium, distinguished as Philo 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). ==See also==