Vol. 58.] TEESDALE, WEARDALE, AND THE TYNE VALLEY. 579 
the basalt-cliffs. Judging, however, by the distribution and large 
size of the boulders of andesite, etc. which occur in the neighbour- 
hood, I see every reason for accepting the Survey reading. 
As the number of easily identifiable rocks in the Dale is small, it 
becomes necessary to trust largely to the nature and distribution of 
the Drift, and to physical features, in order to determine the direc- 
tion of flow of the ice. There is a large number of metalliferous 
veins in the Carboniferous rocks, but as none of them possess any 
very distinctive characters they are not of much use in this 
investigation. 
(2) The Glacial Deposits. 
There are four distinct types of Drift in the area :— 
(az) Asandy reddish or brownish clay, with a large number of well-scratched 
stones. 
(5) A black loamy or peaty clay. 
(c) A coarse gravelly deposit, with many waterworn and a few scratched 
stones. 
(d) A stiff blue Boulder-Clay. 
(a) The red clay with scratched stones is by far the most 
widely distributed of these four varieties. It usually occurs 
in more or less elongated ridges, somewhat after the form of 
drumlins. It is for the most part-confined to the main 
valleys, and is the direct product of ice-action on the rocks 
of the upper part of the Dale. 
(6) The black loamy clay contains very few scratched stones, 
and is found only in some of the small tributary valleys, at 
considerable altitudes above the floor of the main valley. 
This type of deposit is characteristic of such parts of the 
district as can be shown, from other considerations, to 
have been occupied by ice-dammed lakes during some part 
at least of the Glacial Period. 
(c) The coarse gravelly material with waterworn stones 
occurs in long esker-like ridges, which run parallel to the 
trend of the main valleys. It is particularly plentiful in the 
country formerly occupied by the Stainmoor Glacier, and can 
be well seen in parts of Lunedale. 
(d) The dark-blue Boulder-Clay takes the place of the red 
deposit in Upper Teesdale, where the Drift was mostly derived 
from Carboniferous rocks. 
The Drift of Teesdale and its main tributary dales (as, for example, 
Harwood Beck) is arranged for the most part in ridges which are 
approximately parallel to the sides of the valleys. Those ridges 
which occur in the bottoms of the valleys are rounded and are 
of sub-glacial origin—they are, in fact, drumlins. 
The ridges lying nearer to the sides of the valleys are more 
irregular in form, and follow closely the curves of the sides of the 
valley. These appear to be the lateral moraines of the glaciers, 
formed at a time towards the close of the glaciation when the 
