ipio.] 



INLAND-ICE OF THE ARCTIC REGIONS. 



91 



the channels greatly accelerate the velocity of stream flow within 

 those channels, so here within the space between neighboring 

 nunataks a local high rate of flow in the ice is developed. An 

 inevitable and quite important consequence of this constriction was 

 long ago pointed out by Suess and illustrated by the area between 

 Dalager's Nunataks near the southwestern border of the isblink.** 

 Here again the conduct of water which is being discharged through 

 narrow outlets has supplied both the illustration and the explanation. 

 In the regulation of the flow of the Danube below Vienna, the 

 river was partially closed by a dam, the Neu-Haufen dyke, and the 

 floor in the channel below the dike was paved with heavy stone 



Sc«lel :6760(1".80*). 



Fig. 26. a, Closure of the Neu-Hauen dyke, Schiittau in the regulation 

 of the Danube below Vienna (after Taussig) ; b, scape colks near Dalager's 

 Nunataks (after Jensen and Kornerup). 



blocks. The efifect of thus narrowing the channel of the river was 

 to raise the level of the water above the. dike by almost a meter, 

 and under this increased head the current tore out the heavy stone 

 paving of the floor of the channel and dug a depression above as 

 well as below the outlet. This excavation by the current repre- 

 sented a hole dug to a depth of about fifteen meters. The blocks 

 which had been torn out from the pavement were left in a crescent- 

 shaped border to the depression upon its downstream side (see 

 Fig. 26, a). 



"Ed. Suess, "Face of the Earth," Vol. 2, 1888 (translation, 1906), pp. 

 342-344- 



