Rambles among the Channel Islands / by a Naturalist.

Date:
[1855?]
Catalogue details

Licence: Public Domain Mark

Credit: Rambles among the Channel Islands / by a Naturalist. Source: Wellcome Collection.

    398/402 (page 386)
    380 base of granite that the residue of transportable mate- rials may be looked for; and in fact we find in the Valle and St. Sampson tracts entirely overspread by diluvial deposits. By confounding these last with the more recent accumulation of sand and gravel much confusion ensues. The presence of rolled pebbles, of diluvial formation, with some examples of elevated rocks eroded by atmospheric influence, has added to conjectures at variance with geological fact. Such is the structure of our primary series of rocks, and a little examination will prove them to be in exact geological relation with each other, excluding on the one hand the possibility of subsidence, and on the other the supposed lowering of the level of the present sea. If the isle of Portland, or the high hill through which the celebrated Box Tunnel on the Great Western Rail- way is cut, were to subside—one into the sea and the other into the valley to the north of it—no geologist would feel surprised at this movement, however extra- ordinary it might be to the common observer. It is to other causes, then, that we are to look for the present appearance of our low lands and their beds of peat. To the effects of water courses and drainage, added to the alternate movements and encroachments of the sea, and to the power of the wind in transportings and other detritus, we are to look for a solution to the question before us. The same causes are and have always been in operation throughout the latter period at least of this world’s history, and producing results derivable from the continual working and opposing of powerful agents. F. C. L.