AND OBSERVATIONS. 



119 



would be rewarded, by the discovery of many valu- 

 able gems and curious minerals. 



The Don. — The country which stretches from 

 Aviemore to Grantown, and thence south-eastward 

 across the hills to the course of the Don, has little 

 variety in the great scale of primitive rocks. But 

 towards the ancient castle of Kildrummy, a change 

 takes place, from gneiss and mica-slate, on the west 

 or Highland side, to transition rocks, on the east or 

 lowland direction, where a rock occurs which is evi- 

 dently grey-wacke. Kildrummy stands near the 

 junction. On the north side of the ruin, and in 

 the neighbourhood of the gneiss and mica-slate, 

 there are beds or strata of a sandstone, which ap- 

 pears to be an intimate granular mixture of quartz 

 and felspar, with small scales of mica. Of this 

 stone Kildrummy seems to have been built ; and it 

 is still quarried for use. Does it belong to the old 

 red sandstone formation ? 



Corgarff. — Higher up the course of the Don, 

 the gneiss contains beds of quartz, and is sometimes 

 found mixed with hornblende. Near to Corgarff, 

 there are rocks of hornblende, spotted with crystals 

 of light coloured felspar. Another is composed of 

 chlorite and quartz ; and a third of quartz and fel- 

 spar intimately mixed. 



The Dee. — Crossing the country to the bed of 

 the Dee, similar mineralogical appearances occur* 

 At the pass of Balater, one of the entrances in- 

 to the Highlands from the east, there is on the 



