RIVERS. 249 



Grampians to the valley of Strathmore, are per- 

 haps two of the most striking instances of rivers 

 cutting the soil, that are to be met with in Bri- 

 tain. Both rivers drain mountain valleys, the 

 sides of which are steep, and the autumnal rains 

 fall very heavily on both. There is no lake on 

 the Isla to regulate the waters when the rains fall, 

 and on the North Esk there is but one small one 

 (Lochlee), which is far in the mountains near the 

 source of the river, and has little influence on the 

 whole stream, because a great part of the water of 

 floods comes into the channel lower down. 



Each of those rivers has cut a dell, or den, 

 several miles in length, and very deep in propor- 

 tion to its width. But gravel and red sandstone 

 (which in those places is a soft crumbling stone, 

 together with pudding stone, very weakly ce- 

 mented) are the principal matters through which 

 these rivers have cut. Even now the cuts which 

 they have made are little more than sufficient for 

 containing the flood water during the rains. 

 Gannachie bridge is thrown across the dell of the 

 Esk, among the very picturesque scenery at " The 

 Burn ;" and though, in common states of the 

 river, the roadway on the bridge be at least fifty 

 feet above the water, the floods rise so high that a 

 tall man of the village, locally named " Lang Gan- 

 nachie," could reach over the parapet of the bridge 

 and fill a bucket of water. The strata through 

 which the Isla has cut become hard more gra- 

 dually than those at the Esk ; so that the floods in 

 the dell at Airlie do not rise to such a height as 

 those in that at the Burn ; though in late harvests, 

 which are generally those that are more than 



