334 Proceedings of the British Association for 1850. 



remarked that the deep glens of Scotland often presented 

 shapeless masses of clay and gravel at their lower ends, 

 which might be the materials of moraines modified subse- 

 quently by the action of water. 



Mr Hopkins made a statement on " the Dispersion of 

 Granite Blocks from Ben Cruachan." He stated that he 

 had detected them on the beach about Oban ; in considerable 

 mass to the northern extremity of the island of Kerrera, and 

 across nearly the summit of the island. He also found many 

 blocks on the shores of Loch Lomond, Loch Long, and Loch- 

 fine, which he thought might be traced to Ben Cruachan as 

 their original source. His observations were as yet imper- 

 fect, but he hoped, in the course of the present summer, to 

 complete them. He argued that glaciers must have been 

 efifective in transporting the blocks from some of the higher 

 parts of the mountains to those of the lower levels, when 

 they might be subject to other causes, such as floating ice 

 and diluvial currents ; and he conceived it highly probable 

 that the surface of the land of this region had, during the 

 glacial epoch, been submerged considerably beneath the sur- 

 face of the sea ; and that a complete transport of the blocks 

 had been effected by a combination of the actions of the 

 glaciers, floating ice, and currents. 



The Rev. Mr Longmuir, of Aberdeen, then read a paper 

 on the Flints and Greensands of Aberdeenshire, in which he 

 gave a view of the geological structure of Aberdeen and its 

 vicinity, illustrating his observations by reference to the 

 geological map. He then described the district in which the 

 flint nodules abounded, as stretching between Peterhead and 

 the Hill of Dudwick. 



Professor Hitchcock then read a paper on the Terraces in 

 New England, and another on Erosion from river action. Dr 

 Becker made some remarks on the constant increase of Ele- 

 vation of the Beds of Rivers ; and was followed by Mr Bryce 

 on Scratched Surfaces in the Lake District of Westmoreland. 



After the various papers had been read, a general discus- 

 sion was invited. The President having stated Kis opinion, 

 that Mr Chambers had attributed too much to one set of 

 causes, whereas he was inclined to take them all together. 



