35$ ON THE HIGHLANDS. 



little inclined. I have never seen them in fronts 

 nearly perpendicular ; and must therefore con- 

 sider them as either cotemporaneous, or filled 

 from above. 



Some of the appearances which occur, at the 

 place alluded to, where the surface of the rock is 

 almost horizontal, are plainly owing to the origi- 

 nal shape of the subjacent rock ; which might 

 have had points, or small projecting ridges, on its 

 nearly horizontal surface, above which the sub- 

 sequent material being deposited, and after- 

 wards washed or worn away to a smooth super- 

 ficies, has left the appearance of the veins or no- 

 dules, as we now observe them. This idea is 

 completely confirmed by a simple inspection of 

 the splendid perpendicular front which the pre- 

 cipice exhibits on its south side. Here no veins 

 are seen ascending from the reddish rock into the 

 overlying substance. On the contrary, these mas- 

 ses, as already noticed, appear to have been form- 

 ed successively in perfect quietness, and to have as- 

 sociated in the most amicable manner, without 

 the slightest indication of tumultuous or violent 

 concourse. Nor does the superior include fragments 

 of the inferior substance ; for the crystals of fel- 

 spar, which give it the character of a porphyry, 

 are obviously of cotemporaneous formation with 

 the rock itself. 



In this instance, as well as in that of the irre- 

 gular or waved gneiss on the west side of Loch 

 Linnhe^ had the crystals or nodules of felspar and 



