618 
Proceedings of the Royal Society 
front of glaciers ; or perhaps of a lateral moraine, when regard is had 
to there being in some places a train of blocks in almost single file. 
But, on the other hand, I cannot shut my eyes to the possibility of 
these boulders having been carried or pushed into position by ice in 
another form, which came from the west through Glen Tarbert ; and 
which, when it reached the Durer valley, was blocked by the huge 
masses of Scuir na Ulaidli and Ben Fionnlaidh, and then forced 
to sweep down the trench of Glen Creran , carrying boulders, and 
lodging them where they now lie. 
District of Glencoe. — On the western grass clad slopes of Sr on 
Coire Odliar Beg , a hill north of Glen Coe , in the higher part of the 
glen, a number of small boulders, much rounded, were observed of a 
peculiar granite. It was whiter and coarser grained than the well- 
known Ardshiel granite, and had a little hornblende in it. 
They we're in composition altogether different from the rocks of 
the hill on which they were first noticed, which consists of schistose 
breccia. 
The hills to the eastward I had previously examined (Ben a 
Chrulaiste and others), and knew that they consisted of epidotic 
gneiss. 
I therefore thought it probable that the birthplace of the boulders 
would be somewhere to the westward, so in that direction I proceeded. 
On reaching th q Aonach-Eagach range, I found the same boulders, 
fewer in numbers but markedly larger in size. 
They were lying almost exclusively on the eastern side of the 
narrow ridge leading up to the summit, and almost on the summit 
of the nameless peak marked 2938 feet on the 1-inch Ordnance 
map. On the next rounded haunch (2880 feet) they were not seen ; 
but they reappeared on the ridge as it ascended to the eastern peak 
of Meall Dearg (3090 feet), and almost up to the summit of the 
western peak (3118 feet). 
Their position here was most peculiar. They lay upon a ridge 
not many times wider than their own bulk, and only on the eastern 
slopes of that ridge ; while on the lower hills where they were first 
seen, the same boulders lay on the west slopes. 
The parts between Meall Dearg and Meall Garbli , extending to about 
half a mile, are quite inaccessible, and could not be examined. But 
so far as the peaked rocks composing this district could be seen, no 
