96 SOUTH UIST. GEOLOGY. 



of the geologist embracing a wide field must not be 

 limited by variations which are minute, irregular, and 

 inconstant, and which do not affect the broader principles 

 that regulate his investigations. This remark is applicable 

 to many other cases where occasional variations of small 

 extent and importance take place, and where specimens 

 of a distinct rock will intrude into a class otherwise 

 geologically very consistent and strongly defined. Such 

 accidents may perhaps be considered in the same light 

 as the formation of independent minerals in similar situa- 

 tions, and they require attention, lest from an occasional 

 specimen of such anomalous or accidental rocks, the cha- 

 racter of a whole district should be mistaken. 



From Kilbride to Loch Boisdale the position of the 

 gneiss is extremely irregular. It occasionally contains 

 irregular lumps of garnet of an intense brownish black 

 colour, with a vitreous lustre and smooth conchoidal 

 fracture. Although so much resembling granite about 

 Kilbride, it resumes the more common foliated character 

 as it approaches the shores of Loch Boisdale ; abound- 

 ing in hornblende, and containing distinct portions of 

 hornblende schist and of common hornblende rock. 

 Few granite veins seem to exist throughout this tract; 

 where they occur, they sometimes possess the graphic 

 character.* 



From Loch Boisdale to Loch Eynort the hills descend 

 gradually into the sea, but on the right hand of the 

 entrance an abrupt face of cliff is seen of about 100 feet 

 in elevation, tenanted by cormorants and rock pigeons. 

 The external features of these cliffs indicate a difference 

 in their structure and in the nature of the rocks. They 



* The remains of a castle are visible at the entrance of Loch Boisdale, 

 but so far ruined that little more than the foundation exists. This 

 country indeed is as uninteresting to the antiquary as to the lover of 

 natural beauties; offering little or nothing for the gratification of either. 

 Thnt which is rude is not grand, and that which is intricate is hut rarelv 

 picturesque. 



