of Edinhurgli, Session 1882 - 83 . 
207 
the grey granite and greenstone from rocks at and near Schallasaig, 
about 5 miles distant, on the east side of Colonsay, to the IST.hT.E. 
There are also fragments of a bright red granite, with large crys- 
tals ; but no rocks of a similar composition were met with on either 
island. These were found at ‘‘Port na Long,” on the west shore of 
Oronsay, and also at Poll Gorm, on the eastern extremity of Oron- 
say. 
A little to the south of the large sandy bay on the east side of 
Oronsay (Traigh na Sheila), there is a boulder of coarse-grained 
granite, “ of d. pinky colour,” probably the same kind of rock as that 
found at and near Schallasaig. Its size is 3 x 2 x 2 feet.* 
Near this boulder there is one of quartzite, 2x2x2 feet, differ- 
ing in composition from any rocks seen. Beside it there are nodules 
of chocolate red sandstone ; also not seen on the island in situ, 
A little to the south in a narrow gully, there is another coarse 
quartzite 4x3x3 feet, partly bedded in the sand. 
Highest hills in Oronsay (304 feet) are rounded, and the rocks 
near the base are generally smooth, like those now washed by the 
sea. No boulders were seen on them. 
The strand, a low sandy tract, dividing Oronsay from Colonsay 
(covered by the sea at high water), has several boulders of small 
size on it, and in particular one ^of red sandstone and one of a red- 
dish-grey granite. 
On the west side of the strand, on the farm of Garhh,, there are 
several small boulders of grey granite. 
2. Colo7ismj. 
At Schallasaig (a harbour on the east coast) there is a consider- 
able extent of grey granite rocks in situ — and across the island, to- 
wards the west, there is a depression or hollow, which reaches to 
tlie coast. Strewed over this hollow there are blocks of Schal- 
lasaig granite. About half-way across there is a hill about 20 
feet high, called “ Cnoc an Ard RigliS The Schallasaig granite 
rocks apparently come no farther west than this hill, 
* Note hy Convener . — Professor Geikie, in a recent paper published in the 
Transactions of the Glasgov.i Geological Society (\^ol. vi, p. 160) on the “ Geology 
of Colonsay,” mentions, that in the neighbourhood of Schallasaig there is a 
“ granitoid rock” containing /<3?spar, “ which sometimes shows a rosy flush.” 
VOL. XII. O 
