Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/70

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the mountain trap commences, because there only are they seen on the shore. Hitherto I have had no success, although there is a decided difference between the disposition of the two if distant points are assumed. I should have been convinced that such a distinction was to be found though I had failed in finding it, had I not been equally unsuccessful in determining the transition of the two in Mull. Yet I am still inclined to suspect the accuracy of my own observations, and I must leave it therefore as a point to be ascertained by those who shall think fit to follow me.

The junction of the mountain trap with the stratified rocks is very visible for a considerable space between Soa and Loch Scavig. It is here found in contact with the red sandstone, which I have fully described in its proper place. No appearance of the upper strata is here to be seen, the whole body of the mountain following upwards immediately after the sandstone. I know not that any thing worthy of notice exists at the junction. All the strata, both of schist and sandstone, are here as equal and straight as elsewhere, or if they are disturbed it is by the trap veins which are independent of the mountain. Nor are these rocks marked by any particular induration or affection of their composition. Yet I may remark that their angular elevation is less regular than at Loch Eishort, and that they are frequently inclined at much higher angles with the horizon than in this latter place.

It will be readily apprehended from the remarks which have been made in the geographical description of Sky, that the peculiarities in the outlines and appearance of the mountains arise from the mode in which the rocks that constitute them are disposed, and from the forms which these assume during the progress of disintegration. In describing the forms of these rocks I can only pretend to detail the