Cole — Glacial Features in Spitsbergen. 193 



the ice moving, as Maxwell H. Close showed,' from a region of maximum 

 precipitation ratlier than from any tectonic feature. 



rROST-WEATHERING AND SkOW-SLIDE ACTION. 



The most striking fact about Spitsbergen, to one unaccustomed to Arctic 

 hinds, is the general appearance of aridity. The meteorogical conditions allow 

 of precipitation, for the warm inlet of the Atlantic lies near at hand on the 

 south-west, and the temperature on land remains near the freezing-point, 

 even on a summer day. Hence snow falls, and frost-crystals are condensed 

 out of the frequent mists that steal in from seaward. The melting of the 

 snow-edges, however, is said to be balanced by a small precipitation, and 

 broad glaciers are maintained in the lowlands in a country of comparatively 

 little snow-fall. The typical weathering is due to frost and snow-slides, the 

 action of which is evidently rapid. The present snow-line is as high as 

 1,500 to 1,800 feet. 



The horizontal stratification of the rocks in the interior, away from the 

 folded marginal ranges of the west, lends itself to the formation of broad 

 plateaus. The winter snow lies on these as a protective covering ; and the 

 features of coalescing rivulets, and the localization of water-channels, occur 

 only on the margins of the snow-fields.- Since the continuous daylight of 

 summer is accompanied by sufficient warmth, the snow melts in Spitsbergen ; 

 but in most places it retreats only a short distance from the edge of the 

 plateau, leaving patches and long streaks lingering in the grooves (PI. IX., 

 fig. 2). These grooves are eroded in the first instance where the melting 

 edge of the snow allows water to soak into the ground. Frost at night, or 

 even on a cloudy day,^ solidifies this water, and splits the superficial layer of 

 rock. A crumbling surface is produced, from which particles slide away at 

 some points more than at others. At such points water accumulates more 

 freely when melting next begins ; the hollow becomes emphasized, like that 

 of a rill started in the drainage-system of a high bogland. In time, snow 

 gathers more thickly in the hollow than on the smoother portion of the wind- 

 swept plateau-edge. This snow, alternately melting and freezing on its 

 margins, carries on the destructive work. A snow- strip thus works its way 

 down into the edge of the plateau. At times, so much snow is accumulated 



' "Notes on the General Glaciation of Ireland," Journ. R. Geol. Sor. Ireland, vol. i. (1S67), 

 p. 240. A. G. Hbgbom, " Wasserscheide und Eisscheide in SkaudinavieD," Geol. Rundschau, 

 Ed. ii (1911), p. 131. 



-See E. J. Garwood, " Features of Alpine Scenery dne to Glacial Protection," Geographical 

 Journal, 1910, p. 311. 



^ See W. Salomon, "Die Spitzbergenfahrt des internat. geol. Xongresses," Geol. Rundschau, 

 Bd. i. (1910), p. 307. 



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