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at the same time found arranged in long parallel banks, running in 
the exact direction followed by the ice striae and roches moutonnees. 
The arrangement of the till into long parallel mounds is a feature 
with which I have long been familiar.” “ The H.W. and S.E. lakes 
then rest in true rock basins, and also in hollows between parallel 
banks formed wholly of till, or partly of rock and till” (page 542). 
The Convener walked along the banks of many of the lakes in 
the northern part of the Lewis. He does not remember having seen 
much or indeed any rock on those banks. At all events, the 
banks certainly in most cases consist of gravel and till, forming 
“ long parallel mounds ,” as stated by Mr Geikie. On some of the 
heights, as at Bein-na-Bhuna, there are domes of smoothed rock. 
But because they are round and smooth, the Convener does not admit 
that they thereby prove glacier agency. The main facts mentioned 
by Mr Geikie the Convener quite admits, viz., that most of the lakes 
are “occupying hollows in the till and other superficial deposits” — 
that the axis of these hollows is, generally speaking, N.W. and 
S.E. — and that this also is the direction of the ruts and flutings on 
smoothed rocks. Mr Geikie assumes that these lake hollows, and 
these ruts and flutings, were made by one and the same agent, viz., 
ice, which came from the S.E; The Convener, on the other hand, 
ventures to suggest that the ruts and flutings may have been made 
by an agent which came from the opposite direction, viz., the N.W.; 
and that this agent may have been an oceanic current loaded with 
ice, which ploughed through the old sea-bottom, pushing hard stones 
over submarine rocks, which were thereby smoothed and striated. 
There is one general view put forth by Mr Geikie with which 
the Convener agrees. Mr Geikie, after traversing the whole of 
the Outer Hebrides, from the Butt of Lewis to Barra Head, has 
formed an opinion that the phenomena of smoothed and striated 
rocks and boulders in all these islands can be best explained by one 
agent, which embraced and spread over the whole, and reached up 
to at least 1600 feet above the present sea-level. The Convener 
concurs in that view. In all the Hebrides which the Convener was 
able to visit he found a remarkable agreement in the direction of 
boulder transport and of rock striations, and in the disposition of 
superficial deposits. This agreement does certainly suggest the 
agency of some general agent embracing all the islands. The only 
