AT THE CAPE OF GOOD HOPE. 
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of a very small grain, and of a red colour, and full of vertical 
seams filled with quartz, giving it the appearance of vertical stratifi- 
cation. Immediately beyond, the schistus was so mixed up, with 
the granite, that it was difficult to determine whether the granite 
entered the schistus or the schistus the granite ; large veins of the 
former appearing occasionally to enter the latter, and the contrary. 
Passing on, I reached a spot in which the small-grained granite 
spread in an extensive but thin sheet over the schistus ; and I should 
certainly have considered it as a rock of an indefinite thickness if a 
large portion of it had not been broken away, and discovered the 
schistus beneath it. This appearance is well represented in No. I. 
of the Geological Views at the Cape of Good Hope. 
The small-grained granite, from this interruption of its surface, 
extended several yards, when 1 again came upon schistus studded all 
over with large crystals of felspar. This porphyritic rock formed an 
intervening body several feet in extent between the small-grained 
granite and the commencement of another rock formed by an 
intimate mixture of the large-grained granite with the schistus. 
The wood cut very accurately represents a mass of this compound 
rock, which was also several feet in extent. 
