ON THE HIGHLANDS. 



and clay- slate are found alternating, and contain- 

 ing beds of felspar-porphyry, greenstone, and lime- 

 stone. In the structure of the rock at the summit, 

 quartz predominates to a great degree ; and some 

 varieties have brown specks, which are owing 

 probably to iron-pyrites decomposing. 



The conical shape of Ben-Vorlich, viewed from 

 certain positions to the south-east or north-west, 

 is uncommonly regular. On the south-west, or 

 laterally, it resembles somewhat a semi-ellipse, of 

 which the greater axis is the base. Its height is 

 estimated to be 3300 feet. 



In the intermediate ridge betwixt Een-Vorlich 

 and Stuic-a-chroin, the rocks afford a curious 

 field of examination. Masses of clay- slate are 

 observed in situations where it seems to have once 

 existed in greater quantity. There are also small 

 beds and veins of quartz tinged with chlorite ; 

 and the mica- slate exhibits considerable variety 

 of characters in different strata. In some in- 

 stances it is compact, and in others it is coloured 

 with the matter^ sometimes of hornblende, some- 

 times of chlorite. One striking variety is thick 

 slaty and porphyritic, passing into gneiss. Its 

 crystals of felspar and quartz, by which it is dis- 

 tinguished from the common species in its neigh- 

 bourhood, are at first extremely minute, but be- 

 come at length very distinct. Of this kind, many 

 specimens have a strong relation to one of the 

 rocks at the side of Loch-Katterin. — Towards the 

 summit of Stuic-a-chroin, (which appears from 



