From each of these peaks an enormous buttressing ridge sweeps northward until it merges into the foothills and the great plain. These ridges are roughly parallel, and carry between them the Denali Glacier, to adopt Belmore Browne's suggested name, and its forks and tributaries. Up this glacier is the difficult passage to the summit. Tremendous as it is, the greatest perhaps of the north side, the Denali Glacier by no means compares with the giants which flow from the southern front. In 1903 Judge James Wickersham, afterward Delegate to Congress from Alaska, made the first attempt to climb McKinley; it failed through his underestimation of the extensive equipment necessary. In 1906 Doctor Frederick A. Cook, who meantime also had made an unsuccessful attempt from the north side, led an expedition from the south which included Professor Herschel Parker of Columbia University, and Mr. Belmore Browne, artist, explorer, and big game hunter. Ascending the Yentna River, it reached a point upon the Tokositna Glacier beyond which progress was impossible, and returned to Cook Inlet and disbanded. Parker returned to New York, and Cook proposed that Browne should lay in a needed supply of game while he, with a packer named Barrill, should make what he described as a rapid reconnaissance preparatory to a further attempt upon the summit the following year. Browne wanted to accompany him, but was overpersuaded. Cook and Barrill then ascended the Susitna, struck into the country due south of McKinley, and returned to Tyonik with the announcement that they had reached the summit. Cook exhibited a photograph of Barrill standing upon a crag, which he said was the summit. A long and painful controversy followed upon Cook's return east with this claim. In all probability the object of the Parker-Browne expedition of 1910 was as much to follow Cook's course and check his claim as to reach the summit. The first object was attained, and Herman L. Tucker, a national forester, was photographed standing on the identical crag upon which Cook had photographed Barrill four years before. This crag was found miles south of McKinley, with other peaks higher than its own intervening. From here the party advanced up a glacier of enormous size to the very foot of the upper reaches of the mountain's south side, but was stopped by gigantic snow walls, which defeated every attempt to cross. "At the slightest touch of the sun," writes Browne, "the great cliffs literally _smoke_ with avalanches."