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Proceedings of the Royal Society 
about 18 or 20 in number — tbe uppermost resting on the others in 
such a way as to show it had come from N.W. {Lithograph No. 19, 
Plate IX.). 
Near this knoll, a vein of quartz, smoothed on its edges in such 
a way as to show smoothing from N.W. 
(3) On east side of island, near Arinagour, the boulders few in 
number and small. Towards the N.W. part of island, when 
Arniboat schoolhouse is passed, boulders increase in number and size. 
(4) At S.W. end of island, there are many large granite boulders 
near Coll House. Convener measured one and found it 35 x 15 x 8 
feet (312 tons). It was on its S.E. end, leaning on or pressing against 
a gneiss rock. The granite boulder is of a coarse variety, the 
fragments composing it being of large size. This was probably the 
boulder which Captain Stewart was thinking of, when he com- 
pared the large Iona boulder to Coll granite. 
(5) Macculloch, in his account of the Geology of Coll, refers to a 
“ block of augite ” which he found at a great distance from the 
shore, and which he thought must “ be a transported hlochj' as he had 
seen no rock of that kind in the island. He says that it probably 
came from Eum Island, where that rock abounds. Eum is situated 
N. by E. from Coll, and distant about 20 miles. 
Convener omitted to inquire for this augite block. 
8. Eigg . — Mr MTherson, proprietor of the island, drew out for 
the Committee some valuable notes. 
One large boulder rests on the Scopr ridge, — a remarkable ridge 
of pitchstone porphyry which runs for about 2 miles across the 
island in an east and west direction. It reaches, at its east end, to 
a height of 1300 feet above the sea — at its west end, to a height 
of 900 to 990 feet. It rises from a plateau which is about 400 feet 
above sea. 
Both north and south sides of the Scoor are precipitous, almost 
vertical, showing a cliff on the north side of 270 feet, on the south 
side of 400 feet. 
The boulder on this ridge is near its western extremity, and on 
a part of the ridge which is lower than any other part, viz., 890 feet 
above sea. It is close to top of ridge, and on the slope facing the north. 
This boulder is said to be of granite or gneiss — a rock not 
existing in the island. 
