of several papers that were published in the "Transactions" of the Academy of Sciences and of the Geological Society. He made constant endeavors to enlarge the collections, with the result that by the aid of the Swedish mineralogists and of the students, who co-operated with him, and in consequence of the extraordinary richness of the Scandinavian Peninsula in rare and valuable minerals, the cabinet has become one of the most considerable in Europe.
In 1861 he took part in the second expedition of Torell to Spitzbergen, expecting with that to end his excursions toward the pole, and with that view married, in 1863, a Finnish lady, Anna Mannesheim, daughter of ex-President Count Carl Mannesheim. He had, however, already, in December, 1862, crossed on the ice from Sweden to Finland, in order to make some investigations on the formation of sea-ice; and in 1864 he went with the third Swedish expedition to Finland, the business of which was connected with the measurement of the arc of the meridian. His destiny to become an Arctic explorer seems to have been settled with this enterprise, and from it may be dated the beginning of a purpose to conduct explorations on his own account and after his own plans. The next year found him engaged in mineral investigations in Sweden and Finland. In 1867 he went to Paris as a member of the International Metric Commission, attended the Exposition, and made the acquaintance of the men of science of the south.
In 1868 Nordenskiöld went out as the head of the fourth Swedish Arctic expedition, to which Mr. Oscar Dickson, the patron of his later voyages, first gave his generous aid. In this voyage he sought to get as near to the pole as possible, and the sensational achievement of it was that the Sophia reached a higher latitude (81° 42') than had been attained by any vessel in the old hemisphere. Far more scientific importance is attached to the fact that the expedition brought home a rich collection of the fossil plants of the Arctic regions, concerning which but little had previously been known. Another expedition, in which Nordenskiöld was accompanied by Dr. Berggren, was dispatched to Greenland in 1870, having for its principal object to ascertain whether the Esquimau dogs could be relied upon for long sledge-journeys. This question was decided in the negative, but the expedition brought forth scientific fruit second in value to that of no other single one, in that it gave an opportunity to the brave student who led it to examine the remarkable ice-formation of the interior of Greenland, and that it led to the discovery of the celebrated large blocks of meteoric iron of Ovifak, concerning the origin of which a lively scientific controversy has arisen, and which, the explorer himself suggests, may at some future time "form the starting-point for quite a new theory of the method of formation of the heavenly body we inhabit."
Concerning the ice-formation, Baron Nordenskiöld has written: