1867.J Geolotjy. 575 



directions of each of these three lines of disturbance were stated to 

 correspond to the sides of a triangle, as follows : — 



The 1st. (Pre-Permian) lay in a direction . E. 20° N. 

 The 2nd. (Pre-Triassic) „ . North— South. 



The 3rd. (Post-Jurassic) „ . N.N.W. 



The amount of denudation wliich took place in some districts of 

 Lancashire during the first period was shown to have been in some 

 cases prodigious. As an example : according to the calculations 

 of the author and Mr. Tidderaan, his colleague on the Geological 

 Survey, strata no less than 20,000 feet in thickness were swept 

 away in the vale of Clithero before the Permian period. 



An interesting discussion took place in reference to " Eskers," 

 which is a name given to those lines of gravel found in various 

 parts of Scotland and the North of England. Mr. Milne-Home, in 

 describing a remarkable one in the valley of the Firth of Forth 

 ■ — which is clearly indicated on the Ordnance map — compared it 

 with certain banks found by soundings under the Straits of Dover, 

 as shown by the Admiralty charts. The direction of these sub- 

 marine banks is found to correspond with that of the tides, and Mr. 

 Milne-Home suggested that the Eskers of the valley of the Forth 

 had been formed when that valley existed as a strait from sea to sea 

 across Scotland, along which the tidal currents flowed. 



In tracing the line of an old sea-terrace inland in the same dis- 

 trict, Mr. Milne-Home stated that its surface was found to ascend 

 towards the interior from the coast. Sir C. Lyell corroborated this 

 observation, and stated that MM. Bravais and Martin had ascertained 

 that along the coasts and fiords of Norway the old sea-beaches 

 attain an elevation inland many feet higher than along the coast. 

 In order to account for this, Sir C. Lyell threw out a remarkable 

 suggestion. Referring back to the period when these terraces were 

 iu course of formation, and the land was submerged to a greater 

 extent than at present, it seemed probable, owing to the proximity 

 to the Glacial Period, that the mountains of the interior were 

 covered by enormous masses of snow, which would exert naturally 

 an attractive power on the waters of the fiords, drawing them up to 

 higher levels in the interior of the country, and producing a cor- 

 responding rise in the position of the old beaches. 



Mr. C. W. Peach, whose discovery of Lower Silurian fossils in 

 the limestones of Duimess led the way to the reconstruction of the 

 Geological map of the Highlands of Scotland, and enabled Sir 

 Eoderick Murchison to add to his many honours as an original 

 explorer by the establishment of the Laurentian system as the base 

 of the British formations, was present at the Section C, and read an 

 interesting paper on some new forms of fishes from the Old Red 



