CALCAREOtJS REGION 



45 



their fertility. A third portion, reaching from the 

 Susquehannah to the Delaware, occupies the basin of 

 the river Swatara ; traverses, M^ith somef interrup- 

 tions, the branches of the Schuylkill ; and teriiiinates 

 near Easton and Nazareth, the land about which is 

 likewise in repute. Its mountainous boundary to the 

 north east is the ridge of Kittatinny, a continuation 

 of North Mountain ; and to the south-east the ridge; 

 known in that country by the several names of South 

 Mountain, Flying Hills, and Oley Hills, but which is 

 a direct continuation of Blue Ridge. This circum- 

 stance of their bounding one and the same calcareous 

 valley, from the Alleghany arch to Easton, by two 

 lateral chains, is itself a proof of their continuations. 



The other calcareous district, which is contiguous 

 to this, extends along the back of Blue Ridge on the 

 east, from the gap made by the Potowmack to the 

 neighbourhood of the Schuylkill in the county of Lan- 

 caster. It is limited precisely on the south-west and 

 south by the Potowmack and the bed of the great 

 Monocacy, which it does not cross to the east : com- 

 prises the territory of Frederickstown, the greater 

 part of the course of the Patapsco, and the counties 

 of York and Lancaster, which are justly considered 

 as the granaries of Pennsylvania: and lastly appears 

 to lose itself between Norvistown and Rocksbury on 

 the Schuylkill. The remainder of its boundary, from 

 the Monocacy to the Schuylkill, is not marked by 

 heights, though it is a point of division of several 

 waters, and does not give this district the appiearance 

 of a valley, which is observed In the other calca- 

 reous regions. 



There are two striking diSerences between the 



