Vol. 58.] TEESDALE, WEARDALE, AND THE TYNE VALLEY. O97 
fine above, but near its base consists of boulders up to 3 feet in 
length. This gravel rests unconformably upon a mass of contorted 
red Boulder-Clay, which contains tongues and shreds of fine sand 
and gravel. I collected the following rocks from this section, the 
gravel and Boulder-Clay being similar as regards their contents, with 
the exception that local rocks predominate to a greater extent in the 
gravel; many of the boulders, both local and foreign, were well 
striated :—Carboniferous Limestone and sandstone, Millstone Grit, 
Borrowdale volcanics (several well-marked types, including the 
Yewdale breccia and the hypersthene-dolerite of Eycott Hill), New 
Red Sandstone, Dalbeattie Granite, Criffel Granite, Eskdale Granite, 
and Buttermere granophyre. 
Between Haltwhistle and Bardon Mill there is much gravelly 
Boulder-Clay of a prevalent red tint, with patches of gravel here 
and there. The same characters obtain in the portion of the main 
valley from Bardon Mill by Haydon Bridge and Fourstones, to the 
junction of the North and South Tyne at Warden. ; 
North of the main valley similar Drift covers a great part of 
the country up to the outcrop of the Great Whin Sill; and to the 
north of this line the contents of the Drift gradually change, until 
the valley of the South Tyne is reached. The Borrowdale volcanics 
and the other Lake-District rocks are the first to disappear, and to 
the north of Houxby Burn they are entirely absent; but boulders 
of Silurian grit, Dalbeattie Granite, and New Red Sandstone are 
present in large numbers in the bed of that burn, close to its junction 
with the North Tyne. 
North of Bellingham the valley of the North Tyne contains large 
quantities of bluish Boulder-Clay, less gravelly than that of the 
South Tyne and containing boulders derived from the local Car- 
boniferous rocks, with a few consisting of Silurian grit. 
The country between Bellingham and the Cheviots is covered 
with similar material, with a few local patches of gravel, except 
a few of the most prominent ridges, which are swept clear of 
Drift and exhibit glacial striations. Whin-Suill dolerite, though 
absent from the Drift of the upper part of the valley, becomes a con- 
spicuous element immediately to the south of the outcrop of that 
rock at Barrasford. 
I observed several small boulders of Borrowdale andesite in a 
little stream near Walwick Grange (79) on the right bank of the 
North Tyne, about a mile south of the Roman Wall, but none to the 
north of that place. From Walwick Grange southward, Lake- 
District rocks become increasingly numerous, until the South Tyne 
is reached. 
The Drift of the left bank of the North Tyne appears to be 
entirely free from Lake-District rocks as far south as the village of 
Acomb (80). 
Returning now to the right bank of the South Tyne, we shall 
note that the Valleys of the Kast and West Allen and of Devil’s 
Water are encumbered with Drift of a character distinct from any 
Qs, G.8. No. 231. 23 
