The slate, however, becomes more and more metamorphic as we go up, until it passes into what much resembles _trap_.

In some places it looks like _diorite_ and in others like _porphyry_.

I saw no evidence, however, of any outburst.

This latter rock passes somewhat more rapidly into _granite_ at Glen Alpine Springs.

From this point the canyon bed and lower walls are granite, but the highest peaks are still a dark, splintery, metamorphic slate.