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a dense forest of alder and cottonwood grew, proved both 

 by Russell's description and his photographs and also 

 shown by Boundary Survey photographs in 1895. This 

 had entirely disappeared in 1905, but the piedmont bulb 

 was again stagnant and covered by ablation moraine, 

 though with only young alders scattered here and there. 

 Neighbouring glaciers, for instance Atrevida, the nearest 

 to the west, and Black glacier to the east, gave no evidence 

 of similar change, and no such evidence was found in any 

 other glaciers, though it was found later that the small 

 ice tongue north of Haenke glacier had a period of cre- 

 vassing and advance in 1901. 



In 1906 Tarr found four glaciers absolutely transformed 

 and all the others unchanged. The glaciers that were so 

 altered in the brief interval of ten months are, named 

 from west to east: (1) Marvine glacier and the eastern 

 lobe of Malaspina glacier that is supplied by the Marvine; 

 (2) Atrevida glacier; (3) Haenke glacier; and (4) Varie- 

 gated glacier. In the summer of 1905 one could travel 

 upon the surfaces of these glaciers at will. On two of 

 them, Atrevida and Variegated glaciers, Tarr and Martin 

 walked freely, on the former late in August, without 

 recognizing any signs of coming change to activity, though 

 Martin saw signs of the beginning of advance in the Marvine 

 lobe of Malaspina glacier. They were crevassed slightly 

 only here and there, and outside their mountain valleys, 

 were in a stagnant or semi-stagnant condition and covered 

 with a waste of ablation moraine; but in June, 1906, all 

 four glaciers were transformed to a sea of crevasses and 

 not only was it impossible to travel over their surfaces, 

 but it was not even possible to climb up on the glaciers 

 except by the most difficult ice work. Furthermore, the 

 glaciers were even then actively advancing, and the advance 

 extended out even to the fully stagnant margins, over- 

 turning forests of alder and cottonwood that were growing 

 on the outer portions of Malaspina and Atrevida glaciers. 

 Not only were the ice surfaces broken by a maze of cre- 

 vases, but the margins, which had hitherto been gently- 

 sloping, moraine-covered ice banks, were transformed to 

 steep ice cliffs crowned by bristling ice pinnacles. The 

 margins were pushed forward, and the heretofore stagnant 

 piedmont bulbs were thickened. Haenke glacier had 

 advanced to tidal condition; Atrevida and Malaspina 

 glaciers were pushing into the forest that fringed their 

 margin, and Variegated glacier has become notably thicker 



