122 Proceedings of the Royal Society 
of ice, in any form, as a medium of transport had not been 
thought of. 
V. ISLAND OF BARRA. 
This island, near its north end, contains a magnificent boulder. 
Its size exceeds that of any seen by the Convener in Scotland, 
and the site it occupies is full of interest. The legend, before 
referred to, of giants in Barra throwing large boulders to Tiree, 
may have been suggested to the Tiree people, by hearing that very 
large boulders existed in Barra. 
On figs. 7 and 8, two views of this boulder are given, both from 
the north. The first view is taken at about 200 yards, the second 
about 50 yards distance. 
The boulder rests on a broad mass of grave] and sand, with 
numerous cockles in it, at a height above the sea of 230 feet. 
It is distant from the sea about a quarter of a mile. The present 
shore is to the north. The great open ocean is chiefly to the N.W., 
and very partially to the N.E. 
The Convener dug below the boulder in several places, and found 
everywhere sand and fine gravel. A number of rabbit burrows, 
under and about the boulder, confirmed this observation regarding 
the materials of the site. 
The height of the boulder is about 25 or 26 feet. Its extreme 
length is from 37 to 38 feet ; and its width about 18 feet — assum- 
ing two tons for a cubic yard, the weight of the boulder would be 
nearly 890 tons. 
The longer axis of the boulder was found to be ~N.W. by N. 
The flat on which the boulder rests, consists apparently of a 
sea deposit.* Patches of a similar deposit occur in several spots 
round and near the boulder, and at higher levels. Por example, 
there is a rocky knoll, about 100 yards to the west, clustered 
with boulders, 255 feet above the sea. These boulders are lying 
partly on rock, partly on the shelly gravel. Ben Erival is a hill 
adjoining the big boulder on the south, and reaching to a height of 
about 600 feet above the sea. Sand with shells was found among 
the rocky crevices of the hill, up to a height of 457 feet. 
The boulder consists of a coarse gniess almost approaching granite. 
See note on page 67. 
