920 
Proceedings of the Royal Soeiety 
When Scotland was submerged, the currents in this region would 
probably he rapid, looking to the relative positions of the hills and 
valleys. 
If the question he thought of any importance, it may he noticed 
on the Map, Plate XI., that this part of the Spean valley is so sur- 
rounded hy hills, as to he an area well fitted for the reception and 
detention of detritus, its diameter being about three miles. 
Moreover, it is worthy of notice that the valley in which this area 
occurs is contracted at its north end, so that if a current flowOd at 
that end, towards the Spean valley, it would enter the valley 
with considerable velocity, and in virtue of the way in which it 
is surrounded hy hills, it might acquire a circular motion, producing 
whirlpools or eddies. 
It will be found, on consulting the contour lines of the 
one-inch Ordnance Map, that whilst the space where the kaims and 
boulders are situated is (between the contour lines of 1250 feet) 
three miles across, the breadth of the valley to the north, 
between the same contour lines, is only IJ miles (see Sketch 
Map, Plate XI.). To the north of this gorge there is open 
country, and at a low level ; so that if the country was then sub- 
merged there would be opportunity for a large body of water flow- 
ing through the gorge towards the south. 
Xow it is allowable here to observe that there are strong reasons 
for believing that when Scotland was submerged a powerful 
current, with floating ice from some north-westerly point, did pre- 
vail here, as probably elsewhere in Scotland. A few of the facts 
bearing on this point may be mentioned. 
(1) The most important of the lateral glens joining Glen Spean 
is Glen Roy^ which runs for about 1 6 miles towards its head or 
col in a S.E. direction. I extract the following paragraph from 
the notes taken by me when I visited this glen in 1846 : — ‘‘ Visited 
head of Glen Roy. In upper Glen Roy it is interesting to observe 
how uniformly the smoothed surfaces of rocks are to the icest, and 
their rough faces to the east.'’^ 
As this is a point of some importance, I confirm my own observa- 
tion by a quotation from the Memoir of Mr Jamieson of Ellon, who, 
with a view to the ‘‘ Parallel Roads ” problem, made an elaborate 
survey of all the Lochaber glens, Xear the top of Glen Roy, he 
