in Scotland and Parts of England. 271 



At Linksfield, near Elgin, there is a horizontal chink be- 

 tween a limestone bed and the superior oolite strata, from 

 three to four feet deep, and this is filled for several hundred 

 yards inward from its mouth with boulder clay, which has 

 found an entrance from the north-west, and scratched the 

 planes above and below, between which it has been in- 

 sinuated. 



In a few isolated situations, a bed of sand has been found 

 between the boulder clay and the subjacent rocks, and Mr 

 Milne Home mentions an instance in which some of the ma- 

 terials of this sand could be traced to an easterly situation. 



The generally azoic character of the boulder clay is one of 

 its most remarkable features. Besides a fragment of an ele- 

 phant's tusk, represented as having been found in it by some 

 workmen in 1820 at Cliftonhall, in Mid-Lothian, Mr Milne 

 Home, who gave great attention to the formation and its his- 

 tory, had never, in 1838, heard of a single instance of organic 

 matter found in connection with it. More recently, shells of 

 the existing epoch have been found by Mr John Cleghorn, libe- 

 rally scattered through its depths in Caithness ; but they are 

 all water- worn, and can, therefore, be only classed with the 

 inorganic materials. Mr Smith of Jordanhill discovered shells 

 in the like state in the boulder clay ; and Mr Carrick Moore 

 lately announced an entire valve of Astarte compressor, as 

 being found by him in the same formation in Wigton shire, — 

 a solitary exception to the rule. 



I have only within the last few days been made acquainted 

 by Mr Hugh Miller, with a curious and, as yet, unrecorded 

 feature of this mysterious deposit, as it occurs in our own 

 neighbourhood. It is well known that between Leith and 

 Portobello, and between Portobello and Fisherrow, there is 

 a cliff of the boulder clay on which the sea is making per- 

 petual aggressions. The beach in these places is partly com- 

 posed of a rough though levelled platform of boulder clay, 

 with some huge blocks resting on it here and there that 

 have been washed out of the superior mass, now carried away. 

 At several places the eye can detect a narrow train of blocks 

 crossing the line of beach, somewhat like a quay or mole, but 

 not more than a foot above the general level, and not at a 



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