154 FORESTRY OF NORWAY. 
ice-fall from such heights as those of some of the moun- 
tains around, 6,500 feet, and 7,620 feet—a mile and a-half 
above the level of the sea—into a basin 3,980 feet below 
that level, a fall of two miles and a quarter (Can it be), 
and there seems nothing difficult in further imagining it 
excavating such basins as have been mentioned. 
Reference has been made to Loch Awe. The western 
lochs of Scotland appear to abound in such pools, and in 
chains of them. 
In Gairloch, there is at the head of the loch, I was in- 
formed when there lately, a pool very much deeper than 
the basin of the loch, and the basin of the Clyde beyond; 
separated from this bya low range of high land, on which 
is situated Shandon, Row, and Helensburgh, is a dry valley 
of much greater depth in its upper and middle stretches 
than at its lower extremity. And a little beyond is Loch 
Lomond, with a deep pool towards its upper extremity ; 
and another of less depth in the line of its basin a little 
below and within sight of Inversnaid. 
In accordance with what has been said in regard to the 
striae to be seen on the face of the rocks, two theories 
have been advanced in regard to the production of such 
striae observed elsewhere. 
Both theories attribute them to the action of ice. In 
one of these, advanced and expounded in a volume entitled 
Frost and Fire, by Mr J. F. Campbell, they are attri- 
buted to the friction of icebergs and icefloes, drifting from 
the north on ocean currents. In the other, advanced, 
maintained, and illustrated by Agassiz, Ramsay, Lyell, 
Chambers, Jamieson, and Geikie, they are attributed to 
the grating action of glaciers, or land ice, formed where 
they are seen, or at a somewhat higher level, and con- 
tinuously descending in a state of flux to a lower level. 
Thus does it appear to have been here. 
Professor Esmark in a paper On the Geological 
History of the Earth, in Jameson's Journal, October 1826 
