62 Dr. Mac Culloch's Sketch of the 



the mountain trap commences, because there only are they seen on 

 the shore. Hitherto I have had no success, although there is a de- 

 cided 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 des- 

 cribed in its proper place. No appearance of the upper strata is here 

 to be seen, the whole body of the mountain following upwards im- 

 mediately after the sandstone. 1 know not that any thing worthy of 

 notice exists at the junction. All the strata, both of schist and sand- 

 stone, are here as equal and straight as elsewhere, or if they are dis- 

 turbed it is by the trap veins which are independent of the moun- 

 tain. 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 fre- 

 quently inclined at much higher angles with the horizon than in this 

 latter place. 



It will be readily apprehended fram 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 



