Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/130

 while it naturally leads the geologist to inquire into the state of things under which so remarkable a dismemberment of these strata has taken place.

In quitting this part of the skirt of Cruachan it is necessary either to rise to a considerable elevation, crossing above the woods of Inverawe, or to avoid it altogether and make a circuit by Bunawe. We then reach the shore of Loch Etive, and may continue our observations on the base of the mountain. As we ascend to cross the foot of the hill granite appears exclusively, generally in the shape of loose blocks accompanied by similar pieces of porphyry, but sometimes in situ. On reaching the shore beyond Bunawe the appearances become more interesting. The junction of the granite with the schistus is here clearly seen. Large veins may be observed proceeding from the great mass of the mountain, and ramifying into innumerable small divisions penetrating and traversing the schistus in every direction. No where can this appearance which has excited so much attention, be more distinctly perceived, and it is moreover attended here by some interesting circumstances, which as far as I have observed do not occur in the junctions at Loch Ranza, in Glen Tilt, or at Locheil. Two distinct varieties of granite appear in this place; the one a granite according to the strictest acceptation of the term, consisting of reddish felspar, quartz, and mica; the other a syenitic granite, or a compound of white felspar, mica, and hornblende. These are coexistent in every respect and seem to pass into each other, while both of them ramify in a similar manner through the schist, a sufficient proof, if any were wanting, of the geological identity of these two rocks which have so improperly been distinguished by the accidental presence or absence of the single ingredient hornblende. Although the granite veins sometimes run through the schist in a distinct form, just as they do in the junction