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formed by land ice, and in Scotland is generally destitute of 
any true stratification. In Lancashire, however, I have 
several times observed the Lower Till to be truly bedded ; 
and I doubt much whether we have anything which exactly 
corresponds to the Lower Till of Scotland, at least until 
we approach the hills of the Borders and of the Lake 
districts. 
At Blackburn the Upper Till descends into, and forms, 
the valley on which the town is built. It is in some places 
several yards in thickness resting on the Middle Sand, which 
at Pleasanton and Hoghton produces an undulating country, 
sometimes assuming the form of sand-dunes. 
I shall conclude this notice with one remark. There are 
few things more deceptive than steep sections in drift 
deposits on the banks of a river or brook ; and unless the 
observer is aware of the fact, he is liable to error. In cases 
where Till forms the upper part of the bank and rests upon 
beds of sand, the latter is sometimes completely hidden from 
view by a thick wash of the Till, which then seems to form, 
the whole cliff. This is sometimes the case with the banks 
of the Bibble, and arises from two causes : The first is — 
that the sand is easily undermined by the stream, and giving 
way, the Bed Till comes slipping down from above, and 
being more plastic, or cohesive, forms a covering for the 
whole surface. The second cause is — the rain, which softens 
the clay, and when a heavy fall happens, it is carried down 
in a semi-fluid state and spread over the underlying beds. 
It is, therefore, by no means common to find so fine a section, 
showing the three members of the drift series in their 
respective order and thickness, as that described at Balder- 
