180 MINERALOGY OT THE PENTLAND HILLS. 



considerable. The space between the two ex- 

 tremities, is occupied by a double range of hills ; 

 which are separated from one another, in the first 

 part of their course, by a high muirish plain, 

 which extends from the source of the North Esk 

 river to Habbie's How ; and, in the remainder of 

 their course, by a beautiful pastoral valley, through 

 which Logan Water flows. A small range of low, 

 generally round-backed hills, skirts the south side 

 of the group, from Glencross Bridge, nearly to 

 Gaerlips ; and several small hills skirt the group 

 from Swanston, by Bonailly to Kinleith. The 

 hills vary considerably in height. The highest 

 hills in the group, are Black Hill and Caernethy 

 Hill, whose summits are 1 700 feet above the 

 level of the sea ; Kirkyetten is 1544 feet above 

 the level of the sea ; Castlelaw, 1 390 feet ; and 

 Spittal-Law, 1360 feet. 



The hills also vary considerably in form. The 

 most common shape is the round-backed, of which 

 we have examples in the Kirkyetten Hills, Turn- 

 house Hill, Mucks Rig, Spittal Hill, Cock Rig, 

 East Cairn Hill, Hare Hill, Black Hill, and Bald or 

 Bield Hill. Others are conical, as the Kipps, Caer- 

 nethy, Castlelaw, &c. : and some are tabular^ as 

 one of the tops of the hill named East Side Black 

 Hill. The acclivities of the hills, although in gene- 

 ral steep, are so covered with grass, as to afford excel- 

 lent pasture : few cliffs occur, and none are of great 

 height or extent : the most remarkable are those 

 pf Kirkyetten facing Edinburgh, and at Habbie'§ 



