34, 5, 10.—PYTHEAS
The date of these voyages of Pytheas is uncertain beyond the fact that they were somewhere in the 4th century B.C. His Periplus, or notes of his voyage, was extant until the 5th century A.D. The fragments remaining have been published by Arvedson, Upsala, 1824. The objection raised by Polybius to the impossibility of a poor man making such voyages is sometimes answered by the supposition that he was sent officially by the Massilian merchants to survey the north of Europe and look out for places suitable for commerce. The northern sea, which he describes as “like a jellyfish through which one can neither walk nor sail,” is referred “to the rotten and spongy ice which sometimes fills those waters.” This is assuming Thule to be Iceland. Tacitus supposed it to be Shetland (Agr. 10), and described the waters there as sluggish, and not subject to the influence of the wind. See Elton (Origins of English History, pp. 73-74). Elton quotes Wallace (Concerning Thule, 31), who comments on Tacitus by saying, “This agrees with the sea in the north-east of Scotland, not for the reason given by Tacitus, but because of the contrary tides, which drive several ways, and stop not only boats with oars but ships under sail.”