578 Geological Society: — Mr. Lyell on the 



drainage of the country ; and the greater part of the first table-land 

 on the right bank of the Teitli, between Callender and Doune, in- 

 cluding the portion on which stands Mr. Smith's farm, to be com- 

 posed of re- arranged glacial detritus. 



Proofs of Glacial Action at Stirling and Edinburgh. — Having thus 

 shown that glaciers once existed in the glens and mountainous dis- 

 tricts of Scotland, Dr. Buckland proceeds to point out the evidence 

 of glacial action at points but little raised above the level of the sea , 

 and distant from any lofty group of mountains. In 1824 he had 

 noticed that the trap-rock then recently exposed on the summit of the 

 hill [at Stirling] , between the castle and the church, was polished and 

 stiiated, but at his last visit in 1840 these evidences had become obli- 

 terated by weathering. The grooves and scratches described by Sir 

 James Hall on the Costorphine hills near Edinburgh, and on the sur- 

 face of Calton Hill, Prof. Agassiz is of opinion cannot be explained by 

 the action of water ; but they resemble, he says, the effects produced 

 by the under-surface of modern glaciers. In his recent examination, 

 in company with Mr. McLaren, of the Castle Rock at Edinburgh, 

 Dr. Buckland found further proofs of the correctness of the glacial 

 theory, b)' discovering at points where he anticipated they would 

 occur, namely, on the north-west angle of tlie rock, distinct striae 

 upon a vertical polished surface ; and at its base a nearly horizontal 

 portion of rock, covered with deep striae ; also on the south-west 

 angle obscure traces of striae and polished surfaces*. Some of these 

 effects may be imagined to have been produced by stones projecting 

 from the sides or bottom of floating masses of ice ; but it is impos- 

 sible. Dr. Buckland observes, to account by such agency for the polish 

 and striae on rocks at Blackford Hill, two miles south of Edinburgh, 

 pointed out to him by Lord Greenock in 1834. On the south face 

 of this hill, at the base of a nearly vertical cliff of trap, is a natural 

 vault, partly filled with gravel and sand, cemented by a recent infil- 

 tration of carbonate of lime. The sides and roof of the vault are 

 highly polished, and covered with striae, irregularly arranged with 

 respect to the whole surface, but in parallel groups over limited ex- 

 tents. These striae. Dr. Buckland says, cannot be referred to the 

 action of pebbles moved by water ; 1 st, because fragments of stone 

 set in motion by a fluid cannot produce such continuous parallel 

 lines ; and 2ndly, because if they could produce them, the lines would 

 be parallel to the direction of the current : it is impossible, he adds, 

 to refer them to the effects of stones fixed in floating ice, as no such 



* In October 1840, Mr. McLaren found a polished surface on a portion 

 of rock near the south-west base of Arthur's Seat. 



Dr. Buckland has in his possession lithographs copied from drawings made 

 by Mr. .James Hall, of distinct west and east furrows which extend over a 

 portion of the north side of the summit of Calton Hill, and on the surface 

 of the carboniferous sandstone at Craig Leith Quarry. Dr. Buckland saw 

 similar dressings in 1824 in a sandstone quarry near the house of Lord Jef- 

 frey, two miles west of Edinburgh ; and in 1840, in a railway section at 

 Bangholm Bower, one mile north-east of Edinburgh, he found in stratified 

 till and sand manv striated and fluted boulders. 



