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numerous striae on this rock, running about S.S.E., and in that 
direction rising up along the surface of the rock at an angle of about 
9°. Fig. 3 illustrates these facts. 
This direction of the striae upon the surface of the rock, sloping 
in the direction it does, would result from the rock being impinged 
upon by an agent of great weight and power, moving from W.N.W. 
That such was the normal direction of the movement in this 
district is proved by many markings on other parts of the Stirling 
Castle rocks. For example, there are several places where there is 
a narrow defile or gully between the rocks running in a direction 
approximately W.N.W. In these gullies, though the sides are 
smoothed by the friction of some body or bodies passing through 
them, they are not striated, the pressure on the sides not having 
been sufficient to produce striae, these sides having been parallel to 
the movement of the bodies passing between them. 
There are other hills in Stirlingshire which indicate smoothing and 
striation. Thus, on the Abbot’s Craig, near the base of the Wallace 
Monument, at a height of 334 feet above the sea, there are well- 
rounded bosses of rock with deep groovings which run N. W. and S.E. 
So also at Torwood, about 5 miles to the S.E. of Stirling Castle, as 
Sir James Hall first pointed out, there are striations on the rock bear- 
ing N.W. and S.E., at a height of from 330 to 350 feet above the sea. 
Coming now to Mid-Lothian, — on the top of Allermuir Hill, 
one of the Pentlands, at a height of 1647 feet above the sea, there 
are striations on the rocks, as vouched by Mr Croll and by Mr 
John Henderson. On others of these hills, at heights of 900 feet, 
as vouched by Mr McLaren, and of 1100 feet, as vouched by Mr 
Henderson, there are striated rocks. All these are of the same 
character as those in East Lothian. 
How, with reference to the agent by which these striations may 
be supposed to have been produced, it is important to keep in view, 
that at most of the places just mentioned, even at the highest levels, 
there is abundance of clay and gravel. 
Thus, Professor Geikie, in his “ Memoir on the Geology of the 
Neighbourhood of Edinburgh” (p. 126), says: “Boulder clay lies 
along the N.W. flanks of the Pentlands to the height of at least 
1300 feet;” and he adds, that “where the clay has been recently 
removed, we usually find the rock below polished, grooved, and 
