Page:Transactions of the Geological Society, 1st series, vol. 2.djvu/437

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various parts of Scotland.

These mountains are succeeded by a very systematical arrangement of consecutive rocks, terminating at length, on one side, in the sandstone which forms the shore from the Cock to Brodick Bay, and on the others, in various alternations of rocks, which it is foreign to my purpose to describe.

The granite of this group differs essentially in external features from that of the central highlands, and it equally differs from it in character, resembling almost precisely, in hand specimens, the well known granite of Devon and Cornwall.

Like that also it has the bedded appearance which in detached parts so much resembles stratification, and has not unfrequently been mistaken for it. If we were to be guided by the look of a single rock or jutting mass, taken here or there, it would be very difficult to avoid being misled by the impression of stratification which it gives. But if we examine it in a wider view, we shall see that this appearance is fallacious, and that the laminæ, rather than beds, in which it is disposed, are placed in every possible direction; exhibiting even in the immediate neighbourhood of each other, an irregularly tabular form, or lamellar texture, and not a stratified deposition. It is not even possible that these masses should be portions of disrupted strata, as their positions are complicated in a way in which no subsidence, or other subsequent disturbance could have placed them. At any rate it has no better claim to stratification than the granite of Dartmoor and Cornwall—with these it must be classed in geological as it is in mineralogical character.

As the stratification of granite has been a subject of much controversy, it is worth our while to examine those doubtful cases which may be explained by other considerations, and to see what analogies in the disposition of other rocks can be brought to bear

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