AND THEIR MEETING WITH GRANITE. 101 



one of them, though I cannot tell whether or not this was the 

 same which we saw in 1788. Having in this instance traced 

 the communication between the vein and the main mass, I al- 

 most exclusively devoted my attention to it, and, I trust, not 

 fruitlessly. Besides exhibiting by a drawing, (Plate V.), the 

 appearances of this very interesting spot, which is called the 

 Windy Shoulder, I procured a more expressive representa- 

 tion of it in the form of a model, which now lies before 

 us *. 



The Windy Shoulder is situated nearly opposite to the 

 point on the other side of the loch, at which the Shirmers 

 Burn enters it ; the entry bearing from it E. 10 N. by true 

 bearings. 



The strata, which continue here in a vertical position, meet 

 the granite on the surface at an angle of about 45 degrees. 

 The dike runs for about twenty-three or twenty-four feet be- 

 tween two of the strata ; it then starts across them, and re- 

 sumes nearly its first direction, which it pursues for a consi- 

 derable distance more ; making in all ninety feet from the 

 granite. 



I was at the greatest pains to examine the circumstances at- 

 tending the exit of the vein. The earth and vegetation were 

 carefully removed. Some parts of the surface of the rock 

 were dressed by a mason, and a powerful temporary polish was 

 given to that surface by water dashed upon it. All these pre- 

 cautions tended to confirm the identity and continuity of the 

 two rocks, which appeared more and more conspicuously after 

 every fresh exertion that was made to remove the influence of 

 external actions. 



Several 



* I have also presented one of these models to the Geological Society of 

 London. 



