Mr, MacgiUivray ow the Granite of Aberdeenshire. Ij 



northerly direction, you soon come in sight of a magnificent roclj^, 

 with a mountain peak of great elevation behind it. Passing this 

 rock, you enter a valley bounded by very lofty and rugged moun- 

 tains, and terminating in a vast mass, towering above the whole. 

 This mass is Ben-Vrotan, which, together with all the neighbour- 

 ing mountains and rocks, is of coarse-grained granite, of the same 

 nature as that of the Ben-na-muic-dui group, about to be described. 

 At the upper end of the valley, the stream branches, and, follow- 

 ing the course of the western division, you proceed up a narro\^ 

 valley, having a splendid range of precipices on one side. Benight- 

 ed in this valley, I looked up at midnight, and, with a kind of su- 

 perstitious awe, viewed the huge cliffs, partially illuminated by the 

 moon, while masses of grey vapour rolled silently along the moun- 

 tain tops, some of which presented a conical form, with serrated 

 peaks. The rising sun beamed upon a circular hollow or corry far" 

 ther up, in the bottom of which was a lake of light blue water, from 

 which a torrent rolled over the sloping shelves, fringed with nu- 

 merous alpine plants. The streamlets which feed the lake are de- 

 rived from several springs near the summit of the mountain. Pro»- 

 ceeding northward, you come upon a range of precipices, from the 

 summits of which you see a deep valley, with a lake and stream, 

 ending, eastward, in a plain partially covered with pines. This 

 plain is the valley of the Spey. The great mass of which the Ben- 

 Vrotan, Ben-na-muic-dui, and Ben-na-buird groups form a part, 

 is thus situated between the valleys of the Spey and Dee. In all 

 this space there are no human habitations, and the only animals 

 that attract the notice of the wanderer are the red-deer, the grouse, 

 and the ptarmigan, of the latter of which i|nj^eA^eAo<^i at^ KveJ: 

 with on the summits of the mountains. v.j^aY . ,:?; : i ja . : 



Ben-na-muic-'dui Group. — This group consists of several moun- 

 tains of great magnitude, presenting rounded outlines, mural pre- 

 ijipices forming corries, and summits and sides covered with grit, 

 sand, and disintegrating and decomposing blocks and stones. The 

 rock is everywhere granite, and exhibits little diversity in its struc- 

 ture or colour. It is composed of flesh-coloured felspar, dark-grey 

 quartz, and black mica. The latter substance is in small scales, 

 not generally exceeding one-eighth of an inch in diameter, and bears 

 a very small proportion to the other ingredients. The felspar ap- 

 |)ears to form more than half of the mass, and presents concretions 

 of all sizes, from the smallest up to a diameter of an inch. The 

 quartz presents no regularity of form, but in transparency ap- 

 proaches to rock crystal, of which irregular pieces of considerablje 

 size sometimes present themselves. Sometimes also there are ir^ 

 regular crystals of felspar, of the length of about half an inch, iur 

 terspersed. In general, however, the uniformity of the mass is 

 very remarkable, there being few concretions, patches or veins of 

 large-grained granite. Some small veins of white quartz occur. 



