42'4 DEEP MINING IN NOVA SCOTIA — PREST. 



elation ; so that where a trouo-h exists it could not fail to be filled 

 with the results of the erosion of an adjoining ridge. The softness 

 of those upper slates would also guarantee the formation of a 

 trough under ordinary erosive conditions. A considerable ele- 

 vation also seems to be necessary to such an immense denudation, 

 confined as it is to the comparatively short time to which it 

 must be limited. At any rate the evidence seems to justify the 

 conclusion that there once existed higher beds, conformable to 

 our auriferous series as well as superimposed deposits of a later 

 age, all having since vanished through erosion. 



Folding. 



The folds into which our gold-bearing rocks are crumpled, 

 may be roughly divided into three classes, wdiich m.erge gradually 

 one into the other, viz : — circular domes, ellipses and parallel 

 rido-es. The first and second only are found in the western coun- 

 ties ; the second and third in the eastern counties. The most per- 

 fect example of the first is to be seen at Pleasant River Barrens, 

 Lunenburg Co., while the greater part of the western mines 

 belong to the second. Very good examples of the last are seen in 

 eastern Halifax County, where 3 or 4 anticlines lie parallel for 

 over 30 miles, and include the following auriferous localities. 

 Beginning on the north, we have on the first fold, Bollard's 

 Lake, Mt. Thom, Moose River, Cope's Hill, Beaver Dam and 

 Fifteen Mile Stream ; on the second, Gold Lake, North Mooseland 

 and Killag ; on the third, Cowan's Brook, South Mooseland and 

 Lochaber. These parallel folds are sometimes cut b}' short sharp 

 cross synclines or slight depressions, which, however, do not 

 interrupt their continuity to any extent, as at Moose and 

 Salmon Rivers. 



In the western Counties, these cross-synclines are alwaj's broad 

 and deep, often containing beds as high in the series as are found 

 in the main synclines of Halifax County. The result is that the 

 anticlinal domes are irregularly disposed, and the theory of 

 " ranges," so common in the eastern Counties, is not at all appli- 

 cable to the western districts. 



