590 Proceedings oj the Royal Society 
feet, resting on a terrace about 150 feet above the sea. Another 
boulder, of fine-grained granite, lies near it on tbe same terrace. 
Another boulder is on the shore here, 16 x 10 x 9 feet, with the 
longer axis lying E. and W. I learnt from Angus, shepherd at 
Keills (and who also acts as post messenger), that on the Island of 
Dana , at the south side of Loch Swin, there are three boulders larger 
in size than any on the north side. 
On my return to Lochgilphead, I walked to Carig Bay , in the 
parish of North Knapdale, and on the hill to the S.W. facing the 
island of Jura was shown a fine-grained gneiss boulder, 12x6x6 
feet, similar in composition to those at Keills. It was resting on a 
rocky surface sloping down to N.W. Its position suggested trans- 
port from N.N.W. Its height above the sea was 270 feet. 
At Tayvallicli , on the north shore of Loch Swin, I fell in with 
boulders forming two groups of 3 and 4 in number, whose relative 
position indicated transport of the uppermost from the west. 
At Scotnish, also on Loch Swin, found an old sea-terrace at 42 
feet above the sea, with a boulder on it, 18 x 11 x 8 feet, besides 
many others of smaller size. 
In a short lateral valley opening into Loch Swin at Loch Mliurricli , 
I had shown to me by Dr J. M c Leod of Tayvallich an immense 
boulder, 36 x 15 x 13 feet, weighing about 500 tons. It rests on a 
knoll of shingle, and is about 30 feet above the sea-level, and distant 
from it about ^th of a mile. This knoll is in the centre of a marshy 
meadow, which is surrounded by hills of from 260 to 300 feet in 
height, whose sides show beds of sand and gravel. The mouth of 
this small loch opens on Loch Swin to the W. S.W. The boulder is 
many hundred yards distant from the adjoining hills, so that there 
is no doubt that it is an erratic. But from what quarter, and by 
what means has it come 1 One naturally supposes that it must have 
come in by the mouth of the valley, of course at a time when the 
sea was deep enough to float it and lodge it in this cul de sac. The 
sea-bottom on which it dropped may then have been higher than 
the existing meadow; and as the detritus was washed away, the 
boulder may have protected the bed on which it rested, so as to 
form the present knoll. 
I may add that there are numerous small lateral valleys along the 
north side of Loch Swin, extending a few hundred yards, and run- 
