420 M. JEFFERSON GLACIAL EROSION IN THE NORTHFIORD 



inated in the way alluded to as the current explanation. They do not 

 seem to head against cliffs, bnt to slope gently back to the outlying fields 

 of the Jostedals glacier, tongues of which lie in them up toward an eleva- 

 tion of 5,000 feet. They were tributary valleys because fed only by this 

 outlying snowfield, which could never supply an ice stream of the volume 

 delivered into the main valley by the great neve field. 



TJUGEDAL 



This valley was visited and four days spent in its study and that of the 

 neighboring cliffs. It opens on the valley wall at a height of about 1,700 

 feet, the stream coming down abruptly on ledge from 1,400, visible in 

 repeated foaming falls, but between retiring into deep recesses carved in 

 the rock. At the valley mouth the water runs deep cut into the rock, 

 with long slopes of bare gravel leading up some hundreds of feet to 

 benches on right and left. This material resembles a loose till, yet has 

 no strias or certain planing on the pebbles, and the sections visible were 

 all open to suspicion of slipping. All up the valley the stream was 

 deeply cut in these gravels. They do not give a plane valley floor, but 

 one concave to the sky in cross-section. The long section is convex, 

 descending at a slope of 5 degrees in its upper part, which has increased 

 to 15 degrees at the mouth of the valley. Here the plunge is made down 

 a descent so strong that although a path lias been cut zigzagging up it, it 

 is still one of the most toilsome climbs of the region (plate 41, figure 2). 

 Three miles back the valley heads up at a cirque wall, its foot at 3,500 feet 

 and the crest 600 or 700 feet higher. 



SKAALA GLACIERS 



On the south the lofty knife-edge of Skaala overhangs at 6,500 feet, 

 descending by strong black cliffs to twin botner glaciers. These are set 

 deep into the mountain mass, and by their bowl form give it the name 

 (shaal^howl). Their huge moraines form a terrace on the south side 

 of the valley floor. At the valley head lies a snowfield about a mile long, 

 1)ut stagnant, with beautifully clear water issuing from the stones be- 

 neath its lower edge and forming there a tiny lakelet. The surface of 

 this snowfield inclines toward a low point near its center, with an appear- 

 ance of flowing in from all sides. The gurgle of running water is heard 

 underneath at many points. No ledge is visible here save in the walling 

 cliffs and in the deep cut made by the stream. There are lines of mo- 

 raine across the valley. There is no abrupt change of slope from valley 

 floor to rock wall. It is not impossible that the filling is largely talus 

 from the valley sides. Vegetation in the form of deep mosses, heaths, 



