116 DISCUSSIONS IN CLIMATOLOGY. 



which then occupied the Highland valleys, and from 

 which muddy waters escaped in large quantities in 

 summer, owing to the melting of the snow and ice. 

 In short, these Carse-clays appear to coincide with the 

 most recent period of local glaciers. 



During that period some of the glaciers, as Professor 

 J. Geikie has shown, appear to have even reached the 

 sea-level. For example, at the mouth of Glen Brora, 

 in Sutherland, there is a well-marked moraine with 

 large blocks resting upon, and apparently of the same 

 age as, the deposits of the raised beach * Mr. Robert 

 Chambers also observed moraine matter resting upon 

 the 30-feet beach at the opening of Glen Iorsa, in 

 Arran. In many of the Highland sea-lochs, says 

 Professor J. Geikie, glaciers appear to have come 

 down to the sea and calved their icebergs there. 

 This, he thinks, is probably the reason why the 40- 

 50-feet beach is not often well seen at the heads of 

 such sea-lochs. The glaciers seem in many cases to 

 have flowed on for some distance into the sea, and 

 thus prevented the formation of a beach and cliff- 

 line. 



The greater magnitude and torrential character of 

 the rivers of that period were no doubt due to the 

 melting during summer of great masses of snow and 

 ice. The presence of the large Greenland whale, found 

 frequently in the Carse deposits, would seem to indi- 

 cate a somewhat colder sea than now surrounds our 

 island. A decrease of temperature of the sea is what 

 would necessarily occur from a slight diminution in 

 the volume of the Gulf Stream, arising from the 

 greater deflection of equatorial water into the southern 

 hemisphere. 



Another circumstance deserves notice here, as it 



* "Prehistoric Europe," p. 411. 



