48 



in a very obvious manner, the operations of a power- 

 ful south west current.* * 



This opinion receives additional support from 



ther circumstance. The hills on the margin of Jones's 



* In support of this opinion, an interesting fact has recently oc- 

 curred, and which, in this case, is of too much importance to be 

 omitted. 



In the opening and extension of Belvidere-street, in this city, 

 (Baltimore,) it became necessary to cut through a hill, on the west 

 side of Jones's Falls, to the depth of twelve or fifteen feet. This 

 hill is on the very margin of, and constitutes, at that point, the 

 southern border of the granite ridge. 



Its greatest height above Jones's Falls, which is at the foot of it 

 on the east, is about sixty feet ; and is composed of gneiss, in which 

 black horn-blend forms a constituent part. 



In cutting through the hill the workmen came upon the summit 

 of the ridge of rocks, at the depth of nearly ten feet below the sur- 

 face. This it was necessary, in order to follow the grade of the 

 street, to cut away to the depth of about five feet. 



The section or bank on the west side of the street (its course 

 being north and south) presents the following appearances. 



From the point of the ridge, as exhibited in the bank, to the 

 north, and in the direction of the dip of the rocks, the slope of the 

 ridge or rocks, for some distance is gradual. At the point of the 

 ridge on the south side, is a sudden pitch, from the shelving or over- 

 hanging of the rocks. From this point to the extremity of the sec- 

 tion to the south, which is about sixty paces, the bank is filled 

 with rolled pebbles; and immediately at the pitch of the rocks they 

 appear as having been thrown down by cart loads. 



From a strict examination of the whole section, it appears as if 

 the pebbles were driven over the surface or northern slope of the 

 hill by a powerful current until they had arrived at this sudden 

 pitch, when they were let fall or precipitated to the bottom. In. 



