In other words, Lake Valley, with its two summit ridges, _may be regarded as a phenomenon belonging to the order of mountain-formation and not to the order of mountain sculpture_.

I believe an examination of the rocks of the two summit ridges would probably settle this.

In the absence of more light than I now have, I will not hazard an opinion.[3] [Footnote 3: This question practically has been settled by Mr.
Lindgren, and his conclusions are given in an earlier chapter.] _c.

Passage of slate into granite_.

From the commencement of the rocky canyon at the head of Fallen Leaf Lake, and up for about two miles, the canyon walls and bed are composed of _slate_.