94 DR. J. A. SMYTHE ON 



with few stones occurs on the coast, and inland from Bam- 

 brough to Ellingham, rising to 200 feet, which can be proved 

 in places to overlie the typical bluish clay ; and the two clays, 

 preserving the same relationship, can be traced southwards 

 along the coast as far as the Wansbeck. From the rock- 

 contents, it would appear that the grey clay had, in the main, 

 a westerly origin, the reddish clay a northerly origin (Tweed 

 Valley ?). In the Spartley Burn some sections show a reddish 

 clay charged with porphyrite boulders, overlain by a grey clay 

 containing many sedimentary rocks, the evidence thus in- 

 dicating a later movement from some point south of the 

 porphyrite area. Near Sweethope Lough the top clays 

 contain many Dalbeattie granites ; the underlying clays, 

 though alike in character, seems to be free from Scottish 

 boulders. Local clays, as already pointed out, frequently rest 

 on typical boulder clay, the difference in composition and 

 glaciation of the boulders being occasionally strongly marked. 



Only two tracts of limited area appear to have escaped 

 invasion by foreign ice at maximum glaciation ; the one in- 

 cludes Carter and Peel Fells and the region south of these as 

 far as the Blakehope and Plashetts Burns [7], the other com- 

 prises Cheviot, Hedgehope, Comb Fell, and Cushat Law in 

 the Cheviots [6]. Foreign boulders are extremely rare in the 

 drainage area of the Tarret and Tarset Burns, and in fact over 

 the whole tract lying between the North Tyne and the Rede- 

 water; also on the Simonside Hills above 1,100 feet; but the 

 presence of glaciated and striated surfaces in these districts 

 shows that some overriding by foreign ice took place. 



III. — The Glacial Sands and Gravels. 



This term embraces many deposits of different origin which 

 are alike in being of more recent age than the boulder clay on 

 which they usually rest. They form conical or elliptical 

 hillocks (kaims) either isolated, or strung together like a chain 

 of beads, or massed confusedly with crater-like depressions 

 and land-locked hollows, or finally in belts, the longer axes of 

 the individual hillocks being parallel to the general direction 



