1911 Encyclopædia Britannica/Patrocles
PATROCLES (c. 312–261 B.C.), a Macedonian general and writer on geographical subjects, who lived during the reigns of Seleucus I. and Antiochus I. When in command of the fleet of Seleucus (285) he undertook a voyage of exploration on the Caspian Sea to discover possible trade routes, especially for communication with the peoples of northern India. He came to the conclusion that the Caspian was a gulf or inlet, and that it was possible to enter it by sea from the Indian Ocean. The only information as to his work (even the title is unknown) is derived from Strabo. After the death of Seleucus, Patrocles was sent by his successor Antiochus to put down a revolt in Asia Minor, and lost his life in an engagement with the Bithynians.
See Strabo ii. 68, 74, xi. 508, xv. 689; Diod. Sic. xix. 100; Plutarch, Demetrius, 47; Pliny, Nat. Hist. vi. 21; Photius, cod. 224 (on Memnon); C. W. Müller, Fragmenta historicorum graecorum, ii. 442; E. H. Bunbury, Hist. of Ancient Geography, vol. i. (1879); W. W. Tarn, “Patrocles and the Oxo-Caspian Trade Route” in Journal of Hellenic Studies, vol. xxi. (1901).