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edge of a hollow, whicli has been cut out of the sandstone, and 
afterwards filled in with Boulder Clay. The surface of the 
sandstone at the junction, is very much shattered and 
smashed, and large blocks of the rock are embedded in 
the clay. The Boulder Clay is blue, very stiff, somewhat 
gritty, and without the least trace of bedding. The stones 
are mostly small, but a large block occurs every here and 
there ; the majority have their angles and edges blunted ; 
some are quite angular ; a few are well-rounded pebbles. By 
far the larger quantity, probably 99 per cent., are coal measure 
rocks, chiefly sandstone, after which the most numerous are 
flat, blunted slabs of well-scratched black shale ; bits of coal 
were not uncommon. Foreign stones, though not plentiful, 
were easy to find. Carboniferous limestone (ice-scratched), 
chert, and black earthy limestone were the most conspicuous, 
and a specimen was found of blue, closely- grained trap, with 
crystals of iron pyrites. This clay then, which we will dis- 
tinguish as the Lower Boulder Clay, has all the characters of 
the deposit known as Till, which is generally believed to have 
been formed on land beneath an ice-sheet. 
A little further to the north, the Lower Boulder Clay 
becomes covered up by a deposit of a somewhat different 
kind, which we will call the Upper Boulder Clay. This is 
by no means so stiff a clay as the lower bed. It is more sandy, 
and there are fewer stones in it. It contains irregular, inter- 
bedded masses of Warp (laminated clay), and nests and 
lenticular sheets of sand and gravel. The whole is rudely 
bedded, and the beds are in places very sharply contorted. 
The clay is traversed by curved joints or cracks, with polished 
faces, filled in with sand, along which great masses break off. 
A little before reaching the Turnpike road. Warp makes its 
appearance in the lower part of the cutting. The relationship 
of the Warp to the Lower Boulder Clay was not very clear at 
this point, but the two seemed rather to dovetail into one 
