... Pytheas, by whom many have been misled; for after asserting that he travelled over the whole of Britain that was accessible Pytheas reported that the coastline of the island was more than forty thousand stadia, and added his story about Thule and about those regions in which there was no longer either land properly so-called, or sea, or air, but a kind of substance concreted from all these elements, resembling a sea-lungs, a thing in which, he says, the earth, the sea, and all the elements are held in suspension; and this is a sort of bond to hold all together, which you can neither walk nor sail upon. Now, as for this thing that resembles the sea-lungs, he says that he saw it himself, but that all the rest he tells from hearsay. That, then, is the narrative of Pytheas, and to it he adds that on his return from those regions he visited the whole coastline of Europe from Gades to the Tanais.
2. Now Polybius says that, in the first place, it is incredible that a private individual-and a poor man too-could have travelled such distances by sea and by land; and that, though Eratosthenes was wholly at a loss whether he should believe these stories, nevertheless he has believed
Pytheas' account of Britain, and of the regions about Gades, and of Iberia; but he says it is far better to believe Euhemerus the Messenian than Pytheas. Euhemerus, at all events, asserts that he sailed only to one country, Panchaea, whereas Pytheas asserts that he explored in person the whole northern region of Europe as far as the ends of the world--an assertion which no man would believe, not even if Hermes made it.
Concerning Thule our historical information is still more uncertain, on account of its outside position; for Thule, of all the countries that are named, is set farthest north. But that the things which Pytheas has told about Thule, as well as the other places in that part of the world, have indeed been fabricated by him, we have clear evidence from the districts that are known to us, for in most cases he has falsified them, as I have already said before, and hence he is obviously more false concerning the districts which have been placed outside the inhabited world. And yet, if judged by the science of the celestial phenomena and by mathematical theory, he might possibly seem to have made adequate use of the facts as regards the people who live close to the frozen zone, when he says that, of the animals and domesticated fruits, there is an utter dearth of some and scarcity of the others, and that the people live on millet and other herbs, and on fruits and roots; and where there are grain and honey, the people get their beverage also, from them. As for the grain, he says,--since they have no pure sunshine--they pound it out in large storehouses, after first gathering in the ears thither; for the threshing floors become useless because of this lack of sunshine and because of the rains.
...the parallel circle that runs through Thule (which Pytheas says is a six days' sail north of Britain, and is near the frozen sea)...
For not only has the man who tells about Thule, Pytheas, been found, upon scrutiny, to be an arch-falsifier, but the men who have been to Britain and lerne [Ireland] do not mention Thule.... However, any man who has told such great falsehoods about the known regions would hardly, I imagine, be able to tell the truth about places that are not known to anybody.
Now Pytheas of Massilia tells us that Thule, the most northerly of the Britannic Islands, is farthest north, and that there the circle of the summer tropic is the same as the Arctic Circle. ... But in my opinion the northern limit of the inhabited world is much farther to the south than where the summer tropic becomes the Arctic Circle. ... But Pytheas, who misleads people everywhere else, is, I think, wholly in error here too.