46 Smithsoxian Exploration in Alaska in 1904 



The views of the flood plains of the Goodpaster River, presented 

 in plates v and vi, show the annual deposit of ice formed by the 

 freezing' of overflow water and snowdrifts saturated by the same. 

 Deposits of this kind are spoken of as '' annual glaciers." It is 

 seldom that even remnants of them survive from one year to the 

 next. As a rule such accumulations entirely disappear each sum- 

 mer to form again the following winter. This is a transitory form 

 of flood-plain ice and belong- to the same class as river ice, for it 

 has a similar mode of formation. The persistence of this form 

 of ice through the summer is due simply to the fact that the spring 

 freshets are too feeble to disintegrate such winter accum.ulations 

 on the smaller streams as do the floods of the larger rivers. 



Mr. A. J. Collier has observed underground drifts made during 

 mining operations fill with water by infiltration and freeze in the 

 course of one winter so the workings are completely blocked. E. S. 

 Balch, in a work entitled, " Glacieres or Freezing Caverns," Phila- 

 delphia, 1900, gives data on the causes of subterranean ice, pages 109- 

 161, and on page 115, speaking of ice sheets says: " In northeastern 

 Siberia, a form of permanent surface ice is found, which the Tun- 

 gusses speak of as far inn 01, which means ' ice troughs ' or ' ice 

 valleys.' " These tarinnen are broad valleys, with either a horizontal 

 floor or one sloping gently in the form of a trough, over which the 

 ice is spread in the form of a sheet. The Tungusses assert that the 

 ice in some of these troughs never wholly melts away, although it 

 lessens in quantity from the beginning of May till the end of August, 

 after which it once more increases." On pages 166 and 167 Balch 

 mentions the " Subsoil Ice in Alaska," ■" citing I. C. Russell, and 

 " Subsoil Ice in the Klondike Region," ""''' *' Ice Clifl:"s on the Kowak 

 River, Alaska," " and " Subterranean Ice Sheet on Kotzebue 

 Sound." '' 



5, SNOW-DRIFT ICE 



The only ice whose origin can be wholly and positively assigned 

 to drifts of zuind blozcn snow are the accumulations found under 

 sea cliffs and other escarpments, in canons, gullies, and ravines. 



^^ Bulletin de la classe physico-mathematique de I'Academie Imperiale des 

 Sciences de St. Petersbourg, 1853, Vol. XI, pp. 305-316. 



" A Journey up the Yukon River, p. 149, and Second Expedition to Mount 

 Saint Elias, p. 19. 



^'' Philadelphia Ledger, December 30, 1897. 



" Lieut. J. C. Cantwell, National Geog. Magazine, October, 1896. 



" Otto von Kotzebue, Entdeckungsreise in die Sudsee, etc. Weimar, 1821, 

 Vol. IV, p. 140. 



