BY HUGH MILLER. 329 



geologist can pass through the yalley without observing how 

 its lines seem drawn down the sides in the direction of dip, and 

 develop here and there into terraces. Especially he will note 

 how evidently the terraces on the south hank of Erring valley 

 are escarpments thrown back and narrowed through its excava- 

 tion ; and how, in the group of terraciform ridges that has the 

 scaurs of Warksbum at its base, we have the same process in a 

 less forward stage. 



As a rule the outcrops are poorly developed near the valley. 

 This I believe to be due to several causes. There is, in the first 

 place, an ud doubted tendency to obscuration in the process which 

 has opened the large tributaries upon the valley. But farther, 

 the fact that the valley is shallower than before the glacial period 

 has prevented the features from developing again. They are 

 much swathed in drift, and still .retain underneath it the 

 smoothed and curve-fronted forms into which they were abraded 

 by the glaciers. 



The master-ndge, the Y/hinsill, is one outstanding exception, 

 and on the north-east side makes, with the beds sheltered under 

 it, one of the large transverse partitions of the valley. 



Age of the Valley-and Escarpment- System. — It is of the essen- 

 tial nature of geological evidence that it is circumstantial and 

 cumulative. If, in piecing a complicated fracture, it is found 

 that every point meets its hollow and every roughness its answer- 

 ing roughness, that the parts, in short, fit, there is no room for 

 rational doubt that the correspondence betokens connection ; 

 though, in the nature of the case, connection may never have 

 been seen. I have but jjoorly represented the circumstantial and 

 cumulative evidence of this case if it is not seen that the facts 

 and their explanation, so long ago seen, as from a mountain-top, 

 by Hutton, fit, upon the whole, like part and counterpart.'*' If 

 the continuous working of tlie river-system can be postulated its 

 results are sure. But time is everything. The unceasing cry 

 of the geologist is ''Give! give!" How much can be given? 



* There iire generally a few insignificant points in such a fracture tliat prefer hreakiufj- 

 to fitting. Two doubtfully such are mentioned in an appendix. 



