Page:Transactions of the Geological Society, 1st series, vol. 2.djvu/439

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various parts of Scotland.

its existence implies no chemical impossibility. That which occurs on a small scale may occur on a large. The terms are but comparative, and the works of Nature are not to be limited by a measure taken from our own confined dimensions.

Thus we find on the small scale, that antimony is divisible into laminæ, while its sulphuret splits into columns; that mica has a lamellar texture, and asbestos a fibrous one. Should a mountain of the size of Goatfield occur, formed of a solitary crystal of mica, we should not be entitled to call it stratified, while we considered a neighbouring mountain of asbestos to be columnar.

Such I conceive to be the analogies by which we may safely guide our reasonings on this subject. Nor is the great lamellar texture which has so often been considered as the effect of stratification, peculiar to granite. In examining the Cuchullin hills in Sky, I have observed that the syenite and greenstone are bedded as it were in layers, either curved or straight, either horizontal or slightly inclined, resembling so much the disposition of granite beds, that even an experienced eye would at a distance be deceived by them. It is not necessary to illustrate this view by any further analogies, as every person's memory will afford examples in the disposition of some kinds of porphyry. My design is merely to suggest the necessity of considering the greatness of the scale on which Nature operates, and the probable occurrence of a chemical texture, if I may use such an expression, different from, and additional to that which may be observed in the smaller masses, and probably as constant in the larger masses which constitute the different rocks, as the minuter crystallization is in the smaller parts which unite to form them.

Thus far I have only argued on the probability that Goatfield does not consist of stratified granite, by analogical reasoning and