Ancient Moraines in Argyleshire. 



191 



mounds of clay and gravel, crossing the hollowlike embank- 

 ments, and which, if met with in a valley of the Alps, even 

 where no ice was visible, would at once be recognized as the 

 terminal moraines of an ancient glacier. They are very 

 conspicuous, and attract the eye of the traveller as he passes 

 along the road, not only by their forms, which are peculiar, 

 and strange for the situation they occupy, but by the contrast 

 which their smooth surfaces, covered with bright green grass, 

 and furrowed by the plough, present to the dark shaggy un- 

 cultured declivities amidst which they stand. These mounds 

 had evidently, at one time, extended completely across the 

 glen, but the stream whose course they barred, has cut a nar- 

 row passage for itself, not in the middle of the hollow, but 

 close to the eastern ridge. Their external form, like that of 

 the alpine moraines, is very irregular. Sometimes they pre- 

 sent an arched outline across the valley, as in Fig. 3. The 



Fig. 2. Fig. 3. 



upper mounds a and b, Fig. 4, have this shape. Sometimes the 

 two extremities are high, and the middle low ; but in passing 

 over the ground, it is easy to discover that since the materials 

 were deposited, the surface has been much altered by the de- 

 nuding action of the river itself, and the various streamlets 

 which flow down from the western ridge after heavy rains. 

 No section can give a correct idea of the whole deposit; and 

 as one along the middle must have been to a great extent ima- 

 ginary, I have thought it my best course to sketch in Fig. 4, 



Fig. 4. 



the natural section afforded by the deep cut which the river 

 has made in its eastern side, where the composition of the 

 mounds is well exposed, and their approximate depth seen. 



o 2 



