199 
of Edinburgh , Session 1878 - 79 . 
In two parts of the Lewis, where hills prevail, the movement, as 
indicated by the positions of the boulders, and the smoothed sur- 
faces of rocks, has been from W.S.W. At these places (page 26 of 
Eeport, near foot, and page 20, near top,) it will he observed that 
there are low-lying narrow defiles or elongated valleys, forming 
grooves through the country, whose general axis is W.S.W., and 
with rocky sides. 
My idea is, that whilst in the higher parts of the country the 
general traces of a W.H.W. current is everywhere distinct, in low- 
lying valleys, the direction of the current would change, in corre- 
spondence with the axis of these valleys. Hence, in valleys, the 
positions of the boulders are often not the same as at higher levels. 
This remark probably applies to some of the boulders reported on 
by Mr Jolly of Inverness. Thus the Derrie More granite boulders, 
traceable even as far east as Elgin and Lossiemouth, indicate trans- 
port from about W.N.W. On the other hand, the boulders, whose 
parent rocks are situated on the hills forming the sides of the Great 
Glen (viz., Caledonian Canal), have moved, not E.S.E. (the normal 
direction), but E.E. E. There can be no doubt that when the sea stood 
at a height of say 2000 feet above its present level, and with a general 
oceanic current from the W.1ST.W., the current in Glen-na-Albin itself 
— i.e ., between the walls of the valley — would be in the line of that 
valley, forming a deep fissure across the country, running about N.E., 
and that the force of this abnormal current would be sufficient to 
carry boulders transported through it in a north-easterly direction, 
till it united with the more general stream from the W.1ST.W. 
Bofore closing these remarks, I wish to point out, that there are 
two localities mentioned in the Eeport which afford evidence that 
Local Glaciers had existed before the country was submerged. 
These places are Glencoe and Loch Etive. It is shown in the 
Eeport how in the first instance these glens had been scoured out 
and polished by ice flowing down the valleys, bringing rocks, which 
exist in situ only at the head* It must have been after this period 
that submergence occurred, because marine deposits of gravel and 
sand are found in different parts, with boulders resting on them, 
which undoubtedly came from some distant point in the north-west. 
These would have been all scoured out by a Local Glacier, had they 
been deposited at a preceding period. 
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