b AUTUMNS ON THE SPEY. 



heaval, in the highest degree, among the craggy 

 mountains of the Grampians, whose peaks and 

 precipices are composed of granite, gneiss, schist, 

 quartz-rock, porphyry, and other crystalline masses, 

 associated with limestone and micaceous slates. 

 The very plains and valleys are the result of ex- 

 treme denudation, and impress one with the con- 

 viction that the whole of this district was once 

 under the sea. Even the old red sandstone seems 

 to have been washed away, leaving the Silurian 

 system, with its gneissose rocks, flagstones, and 

 clays on the surface, or only covered by the com- 

 paratively recent glacial drift, or " till," which 

 indeed prevails throughout all this part of Scot- 

 land. On reaching that portion of the river where 

 I commenced this digression, we seem first to 

 touch the inner edge of the long belt of old red 

 sandstone that bounds the whole of the Moray 

 Firth, from near the mouth of the Spey in a south- 

 western direction, advancing up the Caledonian 

 Canal nearly twenty miles further than Inverness, 

 and from that town again towards the north-east, 

 along the coast of Ross-shire, including Cromarty 

 and Dornoch firths, and almost the whole of 

 Caithness, where the belt attains its greatest 

 width. 

 The ferruginous character of the rocks, and of 



