242 psocEEDiKGs 01' THE aEOLOGiCAL SOCIETY. [March 20j 



Prof. Mcol's former paper mention had been made of rolled boulders. 

 These occurred at Glasgow and elsewhere covered with Balani. As, 

 however, no marine remains had been found in Glen Eoy, he adopted 

 the freshwater or glacier theory. 



Mr. Daintree, reasoning from observations made in tropical 

 countries, asked whether the terraces might not have been formed 

 during the change of seasons from summer to winter. 



Mr. Evans regretted that no one else v/as present who would in 

 any degree advocate the author's views. He pointed out that if the 

 surface of the rocks below the detritus in Glen Eoy was glaciated, 

 the probability was in favour of the superficial drift being of marine 

 rather than of subaerial origin. He much doubted whether Ben 

 Nevis, or any of the mountains of the district, offered a sufficient 

 gathering-ground for any such glacier as that supposed in the fresh- 

 water theory, assuming the climate to have been such as would have 

 admitted of a large lake in Glen Eoy. He suggested the possibility 

 of the openings through which the sea would gain access to the 

 district having at the time of the last submergence been to some 

 extent choked with ice, which thus checked the tidal action inland 

 from the present coast ; and thought that possiblj' both glaciers and 

 the sea had together contributed towards the formation of the ter- 

 races. These, he observed, were by no means confined to Glen Eoy 

 itself, but were to be seen on a large scale and at a lower level in 

 the valley of the Spean, if not elsewhere. 



Mr. PnESTWiCH observed that both sides of the question had an 

 a priori argument in their favour. There was no doubt of the 

 almost universal giaciation or of the depression below the sea to a 

 depth of at least 1000 feet, and therefore that marine action was 

 possible. The circumstance of the cols marking the height of each 

 terrace was, however, strongly in favour of the fresh-water theory ; 

 but, on the other hand, there seemed an absence of sufficiently 

 elevated land in the Glen Eoy district for the origination of a gla- 

 cier such as was required by this theory. 



Prof. Duncan, suggested the necessity of actual sections being 

 made to sIioav the nature of the terraces and the condition of the 

 rocks below. He referred to a case on a much larger scale in the 

 Yungma valley of East Nepaul, recorded by Dr. Hooker, in which 

 the phenomena of Glen Eoy were repeated on a larger scale, and in 

 connexion with each terrace a glacier and its moraine could be 

 traced. , 



Maech 20, 1872. 



George Attwood. Esq., of San Francisco, California ; Walter Percy 

 Sladen, Esq., Eley House, Halifax ; and William Spencer, Esq., 

 Mining Engineer, Sunderland, were elected Fellows of the Society. 



The following communication was read : — 



