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another ; along the remainder of the section, however, the 
Warp distinctly lay beneath the Upper Boulder Clay. The 
section at the turnpike road showed 
Ft. In. 
Upper Boulder Clay 13 0 
Seam of Warp 0 2 
Upper Boulder Clay 9 0 
Warp 9 0 
Fine Gravel and Sand, not bottomed 5 0 
The Warp is a bluish-brown, very finely laminated, tough 
clay, with small, well-rounded pebbles of carboniferous sand- 
stone and coal ; the bedding was unmistakable, but wavy 
and irregular. 
The gravel at the bottom of the cutting was mostly small, 
but it contained a few large angular boulders of sandstone. 
For some distance, the cutting now shows only Upper 
Boulder Clay resting on Warp, but after a while a boss of clay, 
agreeing exactly with the Lower Boulder Clay of the south end 
of the section, rises up in the bottom of the cutting. A short 
distance further on, the Drift Beds abut against a sloping face 
of coal measure shale. The Warp, near this southern termina- 
tion of the drift, seemed to be replaced by some fine sand and 
sandstone-gravel, in lenticular beds, with nests and layers of 
broken coal ; embedded in this gravel, were some very large 
angular blocks of sandstone, and at its base a layer of angular 
bits of black shale, some of which were ice-scratched. 
The succession of events which this section would seem to 
reveal to us is as follows : — 
First, a valley was excavated in the coal measure sand- 
stones and shales. This valley was afterwards filled in, to a 
greater or less extent, by the clay we have called Lower 
Boulder Clay. The character of this deposit, is exactly such as 
is believed would be formed on land by the grinding of an 
ice sheet; such probably is the origin of this clay. It is, most 
