Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/52

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but the same interference is not visible there, although the parallelism is perfect.

From either end of this junction the limestone beds of the upper series may be traced all round the point which separates Loch Eishort from Loch Slapin, intersected every where like the former by trap veins. Neither the thickness, the number, nor the order of these beds can be ascertained, as they are much too complicated and difficult of access to admit of such an examination. The very attempt would be a superfluous endeavour after accuracy, since enough of them is ascertained to prove that only which is important to be known, the order of their connections with the neighbouring rocks, and the characters by which they can be identified with more distant strata. In general they are formed of thin and thick laminæ, composed of a dark blue earthy limestone, at times somewhat more crystalline, and variously interleaved with argillaceous schist of various dimensions. These beds, like the former, are inclined at an angle of about 25°; they seem most regular as well as thickest at the point of separation between the two Lochs Eynort and Slapin, while near the very same place they are also found in very thin schistose laminæ, so that I imagine there is no rule to be laid down respecting them; they are found occupying the island of Heast, as well as a long ridge of rocks which here intersect Loch Eishort; and they may also be traced at Ord; and further down this shore even as far as Gillan, following the red sandstone, for the same geographical reasons, probably, that I assigned when speaking of that substance. Here however the intermediate bed, that which contains the marble, is deficient, and we have already seen that the blue quartz and schist are also deficient, so that the order is here mica slate, red sandstone, schistose limestone; instead of mica slate, blue schist with quartz, red