176 Proceedings oftlie Royal Society 
present Report, and also in former Reports by the Committee. The 
numerous instances given in these Reports of huge boulders shown 
by their composition to be of northern rocks, clustered frequently 
on the summits or peaks of hills, at heights of 1500 and 2000 feet 
above the present sea-level, seem to leave no doubt regarding the 
soundness of that conclusion to which Mr McLaren had come to 
thirty years ago. 
The other conclusion to which Mr M £ Laren came, and which 
many good geologists of the present day hold, was this, that local 
glaciers had at one time existed in all those valleys. This he 
inferred from observing, that the striations on the rocks were all, as 
he thought, exactly parallel with the axis of the valley, and which 
here generally runs in a direction north-west and south-east ; and 
also from discovering accumulations of gravel and clay in the 
form of elongated embankments — some across the valleys, others 
parallel with the valleys, reminding him of the lateral and terminal 
moraines of Switzerland. 
As to the soundness of this second conclusion, or the correctness 
of the observations on which it was founded, the Committee give no 
opinion. None of the members of the Committee have visited the 
localities, and their function as a Committee has been chiefly to 
collect facts connected with the boulders. Rut it may not be out 
of place to record the fact, that another of our Associates, the late 
Robert Chambers, who had also given much attention to this 
branch of geological science, went to examine the districts referred 
to by Mr M‘Laren, and expressed doubts regarding these last- 
mentioned views. In two papers read by him in this Society in 
December 1852, Chambers states, that on the rocky ridge between 
Lochlong and Holy Loch, at a height of 600 feet above the sea, 
the direction of the striations was not parallel with the valley, but 
“ slanting over the hill ; ” and as the striations were not merely on 
the sides of the valleys, but on the tops of the hilly ranges dividing 
the valleys, he thought they were more probably due to a general 
glaciation of the country than to local glaciers. Chambers quotes 
also the opinion of Sir Roderick Murchison, “ that there is no 
imaginable centre for the issue of glaciers of the ordinary kind down 
the G-airloch.” On this point the Committee offer no opinion, and 
wish only to advert to the investigations of eminent Scotch geolo- 
