From the Sporades and Cyclades the advance was easy to the islands of the Northern Ægean, Lemnos, Imbrus, Thasos, and Samothrace. The settlement of the Phoenicians in Thasos is attested by Herodotus, who says that the Tyrian Hercules (Melkarth) was worshipped there,[572] and ascribes to the Phoenicians extensive mining operations on the eastern shores of the island between Ænyra and Coenyra.[573] A Phoenician occupation of Lemnos, Imbrus, and Samothrace is indicated by the worship in those islands of the Cabeiri,[574] who were undoubtedly Phoenician deities. Whether the Phoenicians passed from these islands to the Thracian mainland, and worked the gold-mines of Mount Pangæus in the vicinity of Philippi, may perhaps be doubtful, but such seems to have been the belief of Strabo and Pliny.[575] Strabo also believed that there had been a Semitic element in the population of Euboea which had been introduced by Cadmus;[576] and a Phoenician settlement in Boeotia was the current tradition of the Greek writers upon primitive times, whether historians or geographers.[577] The further progress of the Phoenician settlements northward into the Propontis and the Euxine is a point whereon different opinions may be entertained. Pronectus, on the Bithynian, and Amastris, on the Paphlagonian coast, have been numbered among the colonies of the Phoenicians by some;[578] while others have gone so far as to ascribe to them the colonisation of the entire countries of Bithynia, Mariandynia, and Paphlagonia.[579] The story of the Argonauts may fairly be held to show[580] that Phoenician enterprise early penetrated into the stormy and inhospitable sea which washes Asia Minor upon the north, and even reached its deepest eastern recess; but it is one thing to sail into seas, and, landing where the natives seem friendly, to traffic with the dwellers on them--it is quite another thing to attempt a permanent occupation of portions of their coasts. To do so often provokes hostility, and puts a stop to trade instead of encouraging it. The Phoenicians may have been content to draw their native products from the barbarous tribes of Northern Asia Minor and Western Thrace--nay, even of Southern Scythia--without risking the collisions that might have followed the establishment of settlements.