690 
Proceedings of the Royal Society 
facing the west, there are horizontal groovings, apparently formed 
by some force, which, acting on the whole mass, has worn down 
certain portions more than others, these portions being less com- 
pact, and so more capable of abrasion. 
Such abrasion might have been effected by a body of water passing 
from the westward ; and more readily, than by the solid ice of a 
great glacier. 
On the top of the ridge forming the south bank of this valley 
(GlenDochart), a cairn stands at a height of 1500 feet above the 
sea. A boulder of considerable size lies on the top of this ridge, on 
the east side of a projecting knoll. Has the boulder been stranded 
on what was the lee side of the knoll ? 
ROSS-SHIRE. 
At Auclinaslieen (Dingwall and Strome Ferry Railway,) there is a 
boulder about 15 feet in girth, which stands on a flat of detritus 
about 610 feet above the sea. 
In this district, there are several other detrital flats, in sight of 
this one, all nearly on the same level. There can be no doubt that 
these flats have been originally one continuous plateau, which formed 
a sea-bottom. It has been cut through by several streams, the banks 
of which, about 18 feet high, show an enormous accumulation of 
gravel and sand; — sand, below (deposited probably when the water 
was deep) ; gravel, above (deposited when the water was shallower 
and more subject to currents). 
The annexed diagram represents a portion of these remarkable flats, 
— cut through by several streams, the principal of which flows from 
Loch Rosque, — situated to the north of the boulder. The knobs, 
on the woodcut are intended to represent knolls of gravel or sand — 
remnants of a greater mass of these materials. The boulder is 
well rounded, and it has evidently come from a distant quarter. 
Professor Nicol of Aberdeen has expressed an opinion * that the 
formation of these Auchnasheen terraces is due to the action of a 
oreat river flowing from the west. I regret to differ on this point 
from a geological friend; but I can see no grounds for that opinion. 
To the east of Auchnasheen, close to the railway, there are several 
spots of rock evidently rounded by friction — whether by ice or by 
* Nicol’s Geology of Scotland, p. 69. 
