142 MR. E. HULL ON THE VESTIGES OF EXTINCT 



those of the Lake district or Wales, in proportion to the 

 greater extent and loftiness of the mountains and their 

 higher latitude. Ben Nevis in lat. 56° 50' attaining an 

 elevation of 4368 feet falls only a little short of the snow 

 line, and is said to have patches of snow all the year round 

 in the fissures near the summit. 



The observations which have been recorded regarding 

 the direction of the strise, although they are lamentably 

 few, go to prove that the Highlands formed a centre of dis- 

 persion, from which the ice-streams and bergs radiated in 

 every direction from the central range. 



The southern slopes of the Grampian Hills in Angus 

 and Forfar have received a detailed examination at the 

 hands of Sir C. Lyell, who has recorded his observations 

 in the transactions of the Geological Society.* The stria- 

 tions follow the lines of the main valleys S.S.E., and 

 several fine examples of lateral and terminal moraines are 

 mentioned. Of these the great transverse barrier of Glen- 

 airn seems to be the most remarkable. The valley of the 

 south Esk here contracts from a mile to half a mile in 

 breadth, and is flanked by steep mountains. Seen from 

 below, this barrier resembles an artificial dam 200 feet 

 high, with numerous hillocks on the summit. Its breadth 

 from north to south is half a mile. Sir C. Lyell considers 

 this to be the terminal moraine of the receding glacier, 

 and considers it probable that it once banked up the river 

 so as to form a lake, which has since been drained by the 

 Esk having cut a channel for itself 30 feet deep on the 

 eastern side. 



The Sidlaw Hills claim particular attention on account 

 of the examples of transported boulders which they afi'ord. 

 Separated by the great valley of Strathmore from the 

 Grampian range they reach an elevation of 1500 feet. 



* Proceedings of the Geological Society of London, vol. iii. ptj ii. 

 P- 357- 



