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Knight's Mechanical Encyclopedia (ed. Knight), M. (search)
hy Arabian; we have here a description of a magneto-electric needle used in the Levant; a magnetized floating needle used in the Indian Ocean; and a correct statement of the Archimedean discovery of specific gravities. This was written about the time of Roger Bacon, 250 years before Da Vinci, 350 years before Porta, and more than 400 years before Galileo and Newton. The Phoenicians circumnavigated Africa in the seventh century B. C., as we learn from Herodotus. Strabo (writing about A. D. 18) says:— If the extent of the Atlantic Ocean were not an obstacle, we might easily pass by sea from Iberia [Spain] to India, still keeping in the same parallel. So Christopher Colon reasoned. See map. It thus appears that the Arab needle had only temporary polarity, and this was probably the case with the Phoenician. It was consulted by the captain, and not kept in a binnacle like the Chinese and the modern needle. Hercules, the symbol of Phoenician enterprise, in his colossal st