According to Nansen, Eratosthenes placed Thule slightly to the north-west of Britain on the basis of the latitudes and distances given by Pytheas. The fact that Pytheas spoke of an island did not necessarily conflict with Nansen’s assumption. How could Pytheas have expected that after sailing for six days from the British Isles he would have come across a continent rather than another island? In order to ascertain that Norway was part of a continent he would have had to sail to the farthest reaches of the Gulf of Bothnia. Even the boldest assumptions did not claim that Pytheas had done that.
So the Thule that Pytheas visited was situated in Norway, somewhere around Romsdal or Nordmore where the longest day of the year was 21 hours. Since there is a clear view to the north from there, it is very possible that the barbarians showed Pytheas the place where the sun went to rest. From here he would also have been able, by sailing along the coast, to continue northwards towards Bodo where it is possible to see the midnight sun. How far north he sailed also depends, of course, on what time during summer the journey was made.
The only thing that Nansen found difficult to explain was the reference to the position of the congealed sea about one day’s journey from Thule and Strabo’s depiction of the merging of land, sea and sky. Nansen believed that both the congealed sea and the sea lung meant a congealed or mushy mass. The phenomenon that Pytheas saw and which inspired him to employ this metaphorical expression was possibly the sludge which is formed in great amounts at the edge of drift-ice when the waves grind the ice into slush. Such slushy ice would fit extremely well Pytheas’ description, according to which one could not walk or sail upon it. If one adds the thick fog which often hangs over areas of drift ice and which envelopes the land and sea in its shroud, the description is credible. If Pytheas stayed in Norway for the winter – and according to Nansen his journey probably lasted more than a year – he might have seen a similar, if more modest, phenomenon in the spring. There is, however, no mention in Pytheas’ book that suggests he wintered there.
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