A. Harker — Glaciated Valleys in 8kye. 



197 



in the exaggeration of features which may be found in some degree 

 in non-glaciated valleys. These are therefore not capable of precise 

 formulation without some kind of quantitative expression, but they 

 are very conspicuous on the ground, and come out clearly in profile 

 sections drawn to true scale. 



(i) The valleys always tend in cross-section to the U rather than 

 the V form. 



(ii) This tendency is most marked in the upper parts of the 

 valleys (Fig. 1' 



Fig. 1. — Two transverse sections across the upper and lower portions of Coir' a' 

 Glireadaidh respectively, viz., from the summit of vSgurr Thuilm to that of Sgurr na 

 Banachdich, and from the western end of the Thuilm ridge to An DiaUaid. 



(iii) The head of a valley is usually expanded into a circular 

 amphitheatre. This is the typical ' corrie ' (equivalent to ' cwm' 

 and 'cirque'), though this term is currently applied to a valley of 

 almost any form. 



(iv) In the centre of such amphitheatre there may be a shallow 

 circular rock-basin occupied by a mountain-tarn. 



(v) In one case (Coruisk) there is a deeper and more elongated 

 rock-basin in the lower and narrower part of the valley. Loch 

 Coruisk is a little over a mile in length, and less than one-sixth of 

 a mile in width. The surface is 26 feet above O.D. and the rocky 

 bottom of the stream at the outlet only a few inches lower. The 

 greatest depth sounded ^ is 96 feet, which occurs somewhat nearer to 



FIG. 2 



Fig. 2. — Longitudinal section down the valley made up of Lota and Harta Corries, 

 teginning at Bealach an Bhasteir. 



the head than to the foot of the lake and only about 80 yards from 

 the north-east shore, from which the hills rise steeply (Fig. 8). 

 Eocky islets occur near the middle and near the foot of the lake. 



^ The soundings were taken by members of the Scottish Mountaineering Club, and 

 are marked on the reduced Ordnance Map accompanying No. 25 of the S.M.C. 

 Journal, January, 1898. 



