120 



MINERALOGICAL NOTICES 



right or north side, an unusually splendid front of 

 granite ; which indeed is found along the course of 

 the river for many miles, sometimes finely porphy- 

 ritic. 



Gairnbridge. — Immediately adjoining the 

 bridge of the Gairn, one of the tributary streams 

 of the Dee, a very remarkable and striking junc- 

 tion of granite and gneiss, on the face of the 

 bank to the north-east, is laid bare for the inspec- 

 tion of the curious. I have never, indeed, seen any 

 thing better calculated to exercise the controversial 

 talents and ingenuity of geological theorists. There 

 •is a substance, consisting of hornblende, felspar, and 

 mica, which, along with syenite, and a fine felspar- 

 porphyry, overlies the primitive rock. 



Cluny water.— The mica-slate nearlnvercauld, 

 contains much granular quartz. On the mineralogy 

 of Braemar, Professor Jameson has lately given us 

 his observations. Leaving the granite of this dis- 

 trict, felspar compact and porphyritic, and granular 

 quartz, are found in beds, alternating to the south- 

 ward of Castleton. Along the road, by the Water 

 of Cluny to the Spitall of Glenshee, about seven 

 miles from Braemar, I observed another junction of 

 the same kind with that of Gairnbridge. Still far- 

 ther southward, the bed of the stream, near a bridge, 

 and not far from its source, presents an interesting 

 alternation of beds of granular quartz, foliated gra- 

 nular limestone, and felspar compact and porphyri- 

 nic 



