177 
of Edinburgh, Session 1878-79. 
the eastward, and projected from the glacier’s surface, would the 
boulder have rested where it fell ? Is it not probable that it would 
have slid down the smooth rock into the sea ? 
The surface on which it lies, slopes steeply towards the sea, in a 
direction W. by N.; and under its S.E. end, there are two small 
boulders which seem to have obstructed progress in that direction. 
These circumstances conveyed to the Convener’s mind the impres- 
sion that the boulder may have been brought by floating ice, and 
been thus landed on the rock which it occupies. 
It is right to add that the smoothed rocks, which occur near the 
shore adjoining the lake, have all the appearance of a great amphi- 
theatre, into which floating ice may have entered, and in which ice 
may have circulated as in an eddy, abrading the rocks forming the 
bottom and sides of the ( amphitheatre. 
This view of the matter is not inconsistent with the theory, that 
before the land was submerged, a glacier had existed in the valley, 
and formed smoothings and groovings also on the rocks as observed 
by Principal Forbes. 
The Convener, seeing the importance of ascertaining beyond all doubt the true 
character of the materials forming the site of the “ Big Boulder, ” in Barra (p. 122), 
wrote lately to Dr MacGillivray of Eoligarry, the tenant of the farm on which 
the boulder is situated, to request that he would dig under the boulder as far 
as could be done with safety, and send a written report of what was found. 
Since these sheets were printed, the Convener has received a letter, from 
which the following are extracts : — 
“ Having at length got milder weather, we proceeded to the ‘ Big Boulder of 
the Glen,’ and made the cuts or drains under it, as you directed, to the depth 
of three feet on both sides, and also at the west end of the boulder. 
“ The first substance found for about a foot deep, was black soil or earth and 
cockle-shells, mixed up with a few stones. Below that, as deep as we could 
conveniently go, very hard gravel and lumps of stone, extremely firm and 
difficult to pick out, — I should say, because being so much compressed by the 
enormous weight of the boulder. 
“ The rock of the hill did not appear at all on any side, or under the 
boulder for three feet at least. It seemed resting entirely on soil and gravel ; 
site very high, almost on the surface, so that a spade can be pushed nearly to 
the centre in one or two places. 
“The stone, to even an ordinary observer, would appear to have been 
brought to its present situation by some agency or other, as the place looks 
quite unnatural to it.” 
