98 W. M. Fontaine—Geology of the Blue Ridge. 
unstratified crystalline rocks, while a band of reddish rocks, 
eighty or one hundred feet thick, show their edges skirting the 
summit. ‘This band is the west edge of the slates which were 
seen resting on the mountain along the east side. 
The Blue Ridge in this part of the State is, as stated before, 
composed of several parallel ranges of nearly equal height. 
The one just mentioned is composed of a species of coarse 
syenite, while the other ranges more to the west are made up 
of the durable quartzites which here form the Lower Silurian 
trata. 
seen. 
some distance next to the slates, on the east, the rock has the 
fine, well-crystallized texture of a diorite. We have here with- 
out doubt an eruption of true igneous rock along the line of 
junction of the two systems, an occurrence not uncommon. 
On the west side we see at the base of the main mass a ledge 
