898 Proceedings of the Poyal Soeiety 
In Glen Etive and Loch Etive there are indubitable traces of 
glacial action at a low level, moving from Loch Awe {Abstract, 
p. 782). 
But in Inverness-shire there are boulders, reported on by Pro- 
fessor Heddle, which, as they must have crossed deep valleys, floating 
ice must be preferred for agency of transport in these cases {Ab- 
stract, p. 829). See also Ruber slaw {Abstract, p. 866) ; Shetland 
{Abstract^ p. 869). Forfarshire {Abstract, p. 801). Sutherland 
{Abstract, p. 875). 
That at the Boulder period floating ice of some kind existed can 
scarcely be doubted. 
The confident testimony of Dr Chambers, Professor Nicol, and 
Mr Jamieson, that the positions of the boulders and the direction of 
the rock striations on the north-west coast are inexplicable, except 
on the supposition that the transporting and striating agent came 
there from the sea, scarcely leaves room for doubt {Abstract, 
p. 795). 
The transport of boulders from the westward is especially interest- 
ing in those localities on the north and north-west of Scotland, 
where towards the west there is nothing but open sea. 
Thus, on the islands of Tiree and Coll, and at Borve on the 
west coast of Harris, the boulders are in such positions, that to 
reach these positions they must have come across the sea. 
In the Shetlands and Orkneys there are on almost every island 
boulders which, differing in mineral constituents from the rocks of 
the island, must have been transported across some portion of sea; 
and accordingly Messrs Peach and Horne, w^ho have lately explored 
the geology and the glacial phenomena of the islands, give a decided 
opinion that on these islands land glaciers were not the transport- 
ing agent. They say that in the Orkneys “ the islands must have 
been overflowed by ice ; ” — ice which “ originated beyond the limits 
of Orkney ” {Abstract, p. 855). So also of Shetland, they say that 
‘At must have been at one time smothered in ice^^—“ originating far 
beyond the sphere of Shetland ” {Abstract, p. 871). 
With regard to the direction of the movement of the transporting 
agent in Shetland and the Orkneys, there is not the same 
uniformity as on the mainland of Scotland. In the island of 
North Hnst, the northernmost island of Shetland, the direction is 
