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Published online by Cambridge University Press: 10 May 2010
page 262 note * That is, in their present condition. When the disturbed earth, by which they are always more or less filled up, is removed, they are of course much deeper.
page 262 note † Hence, the removed material was, no doubt, scattered upon the surface of the ground, without any regular method in its diffusion.
page 263 note * See Proc. 2d S. xi. 161.