294 



PROF. "W. MORRIS DAVIS ON 



[Aug. 1909, 



everywhere by a graded sheet of creeping, tree-covered rock-waste, 

 and drained through an elaborately branching valley- system by 

 well-graded streams, all of which possess that ' nice adjustment of 

 declivities ' which causes them to meet in accordant levels at the 

 many points of junction. An attempt to show such features is 

 presented in fig. 2 (below). It is not necessary for present purposes 



Fig. 2. — Diagram of normal subdued mountains. 



to consider the effect of renewed uplift that has been recognized in 

 certain parts of the North Carolina mountains, because it is prac- 

 tically imperceptible in the headwater streams. Another pertinent 

 example of rounded, non-glaciated mountains drained by generally 

 graded streams with accordant junctions is found in the Cevennes 

 of South-Eastern France. Here the stage of dissection reached in 

 the present cycle of erosion is less advanced than that attained by 

 the mountains of North Carolina, for some of the ridge-crests in 

 the higher Cevennes are rather sharp, and many of the valleys are 

 narrow-floored; nevertheless, that picturesque district affords in- 

 numerable typical illustrations of the mature stage of normal erosion 

 in mountains of moderate relief. An area of still smaller relief, 

 but otherwise illustrating the same principles as those so well 

 exemplified in the mountains of North Carolina and the Cevennes, 

 is the district of the Devon-Cornwall uplands, already mentioned ; 

 here one may see to perfection the matured accomplishment of 

 normal erosion, not only in the perfected grades and the precisely 

 accordant junctions of the branching streams, but also in the 



