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Geological Observations on Abb's Head, made at the Meeting 



therci in June, 1865. By D. Milne Home, Esq. 

 Mr. Milne Home called attention to a spot near the New 

 Lighthouse, where the hard felspathic rocks had been ground 

 down, as well as smoothed and rutted. A thin covering of 

 boulder clay had protected and preserved these smoothed 

 rocks from the influence of the weather, so that when the 

 clay was removed, and the rocky surfaces were washed, in- 

 numerable ruts and striae were discernible. The direction of 

 these was generally from about due North by compass, with 

 occasional variations of a few degrees on each side. The 

 boulder clay had interspersed through it rounded pebbles of 

 hard rocks, which, if pressed heavily and moved over the 

 smoothed rocky surfaces, seemed capable of having produced 

 the ruts and strise. The agent which had ground and 

 smoothed the rocks appeared to have moved from a northerly 

 direction, as the smoothed parts chiefly faced the north, the 

 rough or lee sides facing the south. 



These smoothed rocks did not everywhere present surfaces 

 uniformly flat. They were in some places hollowed out, to 

 the depth of two or three inches — the hollows being elongated 

 — also in a north and south direction ; and the sides of the 

 hollows being also smoothed. 



These elongated hollows seemed to countenance the idea 

 that water, rather than ice, must have acted in their formation. 



The area occupied by these smoothed rocks, in so far as 

 exposed, was about 100 feet in length by about 50 in breadth. 

 It is situated about 20 yards from the precipice overhanging 

 the sea, and is about 200 feet above the sea level. 



To the west and north-west the hills are highest, being 

 about 500 feet above the sea, and distant one mile. They 

 are, however, separated from the promontory of St. Abb's by 

 a deep valley, running north and south, which would prevent 

 any flow of ice from these hills to the smoothed rocks. 



The party proceeded next to the Kirk Hill, distant about 

 half-a-mile to the S.S.W. of the Lighthouse, where Mr. M. 

 H. pointed out a bed of stratified gravel, on the N.W. side 

 of the hill. In this gravel bed, a boulder of grey wacke was 

 observed, on the west side of which were horizontal strise. 

 This gravel bed is about 200 feet above the sea. 



Mr. Milne Home mentioned that on the west side of the 

 valley which separates St. Abb's Head from the mainland, 

 and near its south end, he had, some time ago, found a bed 

 of gravel, consisting chiefly of greywacke pebbles, several of 

 which exhibited strise with a N. and S. direction. 



