Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/58

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with the trap in the same manner as it does in Egg; and in this neighbourhood it also exhibits the same appearance of globular concretions which occur in that little island. It also is found in several places, containing globular masses and fragments of trap, such as are frequent in the similar sandstones, which are seen on the opposite coast of Raasa. The same appearances continue along the shore to Camiskanevig; and although I did not approach the land sufficiently near to be certain of the fact, I am inclined to think that similar arrangements exist all the way to the Altavig islands. Sandstone is found moreover on the eastern side of Loch Snizort; and, I may add, generally on the western shore of Trotternish, particularly at Duntulm, where it contains shells, of which, for the reason mentioned in speaking of the limestone, I neglected to take a sufficient note, not being aware that they might be of future importance in my researches. Here however it alternates with shale; and, unless I am mistaken, with very thin laminæ of coal, such as occur in the sandstone of Egg, while it also contains imbedded fragments of charcoal, and I am therefore inclined to think on these indications, that this sandstone belongs to a deposit still superior to that of Strathaird, and probably the same as that which is found in Egg. The last white sandstone which I met with was in Glamich, where it was penetrated by veins of trap and mingled with the mass of the hill, but the space I saw exposed was so very small that no conclusions could be drawn from it.

I must not terminate the description of these strata without pointing out a circumstance of importance which might otherwise escape the reader's attention, namely, the conformity of all these rocks. I will omit that conformity which in some places appears to exist between the mica slate and quartz rock, and the incumbent ones, because it is certainly incomplete; but between the bed which consists of blue quartz rock and slate, and the red sandstone, it is