Nansen continued the work in which he took the deepest interest--the bathymetrical features of the Norwegian Sea, his chief aim being the greatest attainable accuracy in the construction of instruments and the working out of results[161]. In 1914 he accompanied a Russian expedition through the Kara Sea to the Yenisei, and went by land across Siberia as far as Vladivostok. The result was a most interesting narrative, but it is the appendix which will prove most valuable to polar students and navigators. He here gives a list of all the Kara Sea expeditions from Stephen Burrough in 1556 to the date at which he wrote, with the results of their voyages; and then, with the information derived both from books and from his own experience, he explains the causes of the prevalence of obstructive ice and of its absence. His conclusion is that steamers should very rarely fail to get through the ice of the Kara Sea[162]. The great literary achievement of Fridtjof Nansen was the publication of the valuable work entitled _In Northern Mists--Arctic Exploration in Early Times_ (1911). It is a monumental work, entailing an incredible amount of careful research, and the materials are put together and presented with the skill and judgment of a master hand. In his deeply interesting introduction, Nansen answers the question “What were they seeking in the ice and cold,” by a quotation from the old Norse chronicle, the _King’s Mirror_:-- If you wish to know what men seek in this land, or why men journey thither in so great danger of their lives, then it is the threefold nature of man that draws him thither. One part of him is emulation and desire of fame, for it is a man’s nature to go where there is likelihood of great danger, and to make himself famous thereby. Another part is the desire of knowledge, for it is man’s nature to wish to know and see those parts of which he has heard, and to find out whether they are as it was told him or not. The third part is the desire of gain, seeing that men seek after riches in every place where they learn that profit is to be had, even though there is great danger in it. Nansen himself puts it more tersely yet scarcely less impressively. “From first to last the history of polar exploration is a single mighty manifestation of the power of the unknown over the mind of man.” CHAPTER XXXIX THE PARRY ARCHIPELAGO--SVERDRUP The very important voyage of Captain Sverdrup may be looked upon as a sequel to the voyage of Nansen. The same generous patrons of Arctic enterprise, Axel Heiberg and the brothers Ringnes, resolved to equip another Arctic expedition and, by the advice of Nansen, the command was offered to Sverdrup, the selection of the route being left to the commander.