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NEW YORK STATE MUSEUM 



steepness of gradient of river course and dip of rocks, where the 

 two are equally directed, should assume large proportions since 

 this would presuppose but a slight difference of steepness in the 

 two and a like direction over a long distance. Nevertheless the 

 geologic maps reveal such large inliers. An especially clear ex- 

 ample seems to be that of the inliers on the coastal plain of the 

 Carolinas 1 [see text fig. 13]. There we seethe Upper Cretaceous 



appear in long tortuous strips, 70 miles and more in length, from 

 under the Neogen along the Pedee river, the branches of Cape 

 Fear river and Neuse river, in order to disappear again under 

 tertiary beds above the mouths of these rivers. The relations of 

 the strike of the tertiary and cretaceous formations and of the 

 courses of the rivers to the coast line indicate that the dips and 

 river courses are approximately coincident. 



b Solution inliers. In some of the small inliers of Lowville lime- 

 stone in the Black River limestone of the Watertown region, there 

 is fair evidence that solution has played an ■important part in the 

 removal of the overlying rock. This is especially the case in the 

 inlier along Perch river below Limerick \sce text fig. 14, 15]. 

 The longitudinal section shows that the river plunges with a high 

 fall from the Black River into the Lowville, upon whose hard bed 

 it flows for half a mile in order to disappear above the " Natural 

 Bridge " under the Black River limestone. Just to the south of the 



1 Willis, B. Carte Geologiquc del' Amerique du Nord. 1906. 



