PTOLEMAIC STSTEM. 520 sary. As observations of the heavens increased in accuracy it was found that the heavenly mo- tions were apparently not uniform, and this was explained as fullov.s: The acceleration of the sun on one side, and retardation on the other side of his orbit, is only apparent, and results from the earth not being in the centre of his sphere, C (see Fig.), but at E, and consequently his mo- PTOLEMY. PTObKMAIC SYSTEM. tion appears to be slowest at P, and quickest at R. The alternate progression and regression of the planets was accounted for by .supposing them to move, not directly with their crystallines, but in a small circle, whose centre was a fixed point in the crj'stalline, and which revolved on its axis as it was carried round with the latter; thus (Fig.) the planet was carried round the small circle ABD, as that circle was carried round PQR (now supposed to represent the planetary crystalline). The planet while in the outer por- tion of its small circle would thus have a for- ward, and in the inner portion a backward mo- tion. The larger circle was called an eccenlric, and the smaller an i-jjici/cle (q.v.). This theory of eccentrics and epicycles satisfied the early astronomers; but further investigation showed its incompleteness, and in later times it was found necessary to explain newly discovered dis- crepancies by heaping epicycle upon epicycle, till such a complication of the .system had been pro- duced as drew from Alfonso X. of Castile, to whom the Ptolemaic system was being explained, the remark that "if the Deity were now to recon- struct the world, he (Alfonso) could give him a few useful hints." As soon as astronomers came to understand and test the Vopernican system the Ptolemaic system was discarded. See Co- pERNicAN System ; Galileo. PTOLEMAIS, tol'e-ma'is. The Roman name of a seaport of Syria, now known as Acre (q.v.). PTOLEMY, tol'e-mi (Lat. Plohnuvus; from Gk. IlToXe^aros, Ptfiteniaios) . The name of six- teen kings of Eg>'pt forming the Thirty-first or Macedonian Dynasty, which ruled from B.C. 323 to 30. Ptolemy I. (c.367-283 b.c), surnamed Soter ('the Preserver'), was a Macedonian, the reputed son of Lagus. He displayed marked ability as a soldier and was one of Alexander the Great's favorite generals in his Eastern campaigns. On the death of Alexander (B.C. 323) and the di- vision of his possessions, Egypt and Libya fell to the share of Ptolemy and. while nominally only satrap of these provinces, he was from the first virtually an independent ruler. In B.C. 300 he became King in name as well as in fact. Under his able rule Eg>'pt became a power of the first rank. Palestine and Southern Phoenicia, Cyprus, Libya, and Cyrene were included in her posses- sions, and Eg^'ptian influence was paramount in the ilediterranean. The new capital, Alexandria, soon became the foremost city of the world, both in commerce and in culture. The famous nuiseum and library founded b}' Ptolemy L, and fostered by his successors, exerted a profound influence and attracted to Ale.xandria men of letters and of science from all parts of the Hellenistic world. The King himself was the author of a history of Alexander the Great, a work of which Arrian (about A.D. 134) made free use in the composi- tion of his Anabasis. Ptolemy was a wise admin- istrator and skillfully reconciled the opposing in- terests of his Greek and Egyptian subjects. In B.C. 285, after a most successful reign, he abdi- cated in favor of his son, Ptolemy II. Ptolemy II. (b.c. 308-247), surnamed Phila- DELPius, the son of Ptolemy I. by Berenice, the grandniece of Antipater, was born on the island of Cos. He reigned from B.C. 28.5 to 247. He first married Arsinoe, the daughter of Lysinia- chus, King of Thrace, but eventually banished her, and, in compliance with ancient Egyptian custom, married his own sister, Arsinoe. Phila- delphus undertook no great wars, and under his peaceful reign Egypt prospered greatly. The security afforded by her maritime supremacy, supported by a powerful fleet, stimulated her Mediterranean commerce to a lively activity, and a great trade developed on the Red Sea with Arabia and the Somali coast. This trade was encouraged by the establishment of new ports, by reopening the old route through the Wadi Hammamat to the Red Sea, and by planting a colony, called Ptolemais Epitheras, on the Afri- can coast near the site of the modern Suakin. A canal was also opened from the upper end of the Red Sea to the Nile. An important work, undertaken in the reign of Philadelphus. was the famous lighthouse erected on the island cjf Pharos, at the mouth of the harbor of Alexan- dria, by Sostratus the Cnidian. The Egyptian history of Manetho is reported to have been com- piled at the suggestion of Philadelphus, and tra- dition alleges that the King caused the Hebrew scriptures to be translated into Greek by seventy (or seventj'-two ) elders sent from Jerusalem for the purpose. See Septuagint. Ptolemy III. (c.282-222 b.c), surnamed EuERGETES ( 'the Benefactor' ) , was the son of Ptolemy II. by his first wife, Arsinoe, daughter of Lysimachus of Thr.ace. He succeeded his father in B.C. 247, and reigned until B.C. 222. He married Berenice, daughter of Magas, the step- son of Ptolemy I., who brought Cyrene as her dowry. In the beginning of his reign he made war upon Syria to avenge the unirder of his sister Berenice; widow of Antiochus Theos. Ptolemy overran the Seleucid dominions as far as Babylon and Susa, but, after an absence of three years, he was called liomc by the news of domestic disturbances. He brought with him an immense booty, which included the inuiges of the Egyptian gods carried away by Cambyses. It was the restoration of these images to their proper temples that gained for the King his title Euergetes, and this act also furnished the mo- tive for the Decfee of Canopus pas.sed in his honor by the Egyptian priesthood in B.C. 23S. The result of the war placed Ptolemy in possession of all Coele-Syria, tngefher with Damascus and the port of Antioch. and gave him the control of the sea up to the Hellespont and the coasts nf Thrace. He wisely made no attempt to hold the more distant Asiatic possessions of the Seleucid
