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VI. — Indications of Glacial Action in Cornivall. — By Nicholas 

 Whitley, F.M.S., one of the Honorary Secretaries of the Boyal 

 Institution of Cornivall. 



Read at the Spring Meeting, May 18, 1869. 



THE evidence of glacial action, so abundant and conclusive in 

 the northern parts of Great Britain and Ireland, is much 

 less obvious in this extreme south-west of England; and has 

 been supposed to be altogether wanting. It has therefore been 

 assumed that while Wales was submerged in the glacial sea full 

 2000 feet below its present level, Cornwall, Devon, and the South 

 Coast of England remained, as now, dry land. 



There has, however, of late years been a gradual accumulation 

 of evidence tending to a contrary conclusion. The " boulder-clay " 

 is said to form an extensive deposit, a considerable height above 

 the sea, at Freming-ton, near Barnstaple ; boulders of granite, trap, 

 and basalt, with water-worn chalk flints, are found in the " drift 

 beds " on the shores of Barnstaple Bay, and may be traced up to 

 their parent rocks in the north of Ireland ; and the large mass of 

 " diluvium " on Crowsa Downs, 300 feet above the sea, appears 

 to indicate that that part of our county was sunk to at least that 

 depth in the glacial ocean. 



I propose in this Paper to offer some additional evidence on 

 this subject, tending to the same conclusion. 



The submarine "forest beds" which may be traced around 

 the coasts of Cornwall and Devon are found under similar 

 circumstances along the coasts of England, Ireland, Wales, and 

 France ; and the subsidence of the land by which they were sub- 

 merged was therefore very uniform over an extensive area ; and it 

 is thus most improbable that Wales should have sunk 2000 feet in 

 the Glacial Sea and the contiguous land of this south-west peninsula 

 have remained stationary. The structure of the so-called " raised 

 beaches " which fringe our bays differs in many respects from the 



