904 
Proceedings of the Royal Society 
‘‘considerable interest,” it may be allowable to inquire whether any 
circumstances exist calculated to throw light upon it. 
The glaciation and striae on the rocks at Eide were by Dr 
Chambers ascribed to agency which came “ from the north,” viz., 
sea-ice. By Professor Geikie these were ascribed to the agency of 
land-ice, filling what is now the sound of Nordskaale, of which 
land-ice, one portion flowed north towards Eide, and the other por- 
tion held on a southerly course, each thus flowing in opposite 
directions from what had once been a col, or head of two separate 
valleys. 
(1) There is one circumstance which seems to favour the view 
taken by Chambers, viz., that Mr Allan, when he examined the 
rocks, evidently considered that the agent which produced the 
markings, was the sea. He adopted for an explanation of 
these. Sir James Hall’s opinion, suggested by the similar 
phenomena on Corstorphine Hill, viz., diluvial agency. The 
smoothed and striated rocks on the sea-coast at Eide forming a 
“ headland,” as Mr Allan called it, would no doubt seem to him 
well suited to illustrate such an agency. He accordingly takes 
notice of these rocks as “ scooped and scratched in a very wonderful 
degree, not only on the horizontal surface, but also on a vertical one, 
of 30 to 40 feet high, ivhicli had been o'pjposed to the current, and 
presented the same scooping and polished appearance with the rest 
of the rocks, both above and below 
If this be a correct view of Mr Allan’s opinion, he is so far a 
witness corroborative of Chambers. 
(2) Another circumstance bearing on the question, is the apparent 
difficulty of any glacier being formed which could reach the rocks 
at Eide, glaciated as they are, up to a height of 1302 feet (Abstract, 
p. 879). 
The distance of Eide from the col (from which Professor Geikie 
supposes the glacier to have flowed in -its northward course) is 
between 8 and 9 miles. At the col (as the map shows) the valley 
is exceedingly narrow, and the hills on each side apparently are not 
so high or so shaped as to afford good gathering ground for a large 
accumulation of ice. The hills there do not seem to be above 2000 
feet high. Supposing ice to have filled the valley there even up to 
that height, and to flow towards the north, would it ever reach Eide ? 
