A Dictionary of Greek and Roman biography and mythology

(Ἀγαθαρχίδης), or AGATHARCHUS (Ἀγάθαρχος), a Greek grammarian, born at Cnidos. He was brought up by a man of the name of Cinnaeus; was, as Strabo (xvi. p.779) informs us, attached to the Peripatetic school of philosophy, and wrote several historical and geographical works. In his youth he held the situation of secretary and reader to Heraclides Lembus, who (according to Suidas) lived in the reign of Ptolemy Philometor. This king died B. C. 146. He himself informs us (in his work on the Erythraean Sea), that he was subsequently guardian to one of the kings of Egypt during his minority. This was no doubt one of the two sons of Ptolemy Physcon. Dodwell endeavours to shew that it was the younger son, Alexander, and objects to Soter, that he reigned conjointly with his mother. This, however, was the case with Alexander likewise. Wesseling and Clinton think the elder brother to be the one meant, as Soter II. was more likely to have been a minor on his accession in B. C. 117, than Alexander in B. C. 107, ten years after their father's death. Moreover Dodwell's date would leave too short an interval between the publication of Agatharchides's work on the Erythraean Sea (about B. C. 113), and the work of Artemidorus.

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