of Edinburgh, Session 1879 - 80 . 
627 
sion of surprise, that any one could have made the mistake of not 
seeing this fact, it was so palpably evident.” 
3. In Harris , Professor Heddle found that on the southern 
flanks of the hill called Gilebhall Glass , rocks were striated up to a 
height of 500 feet, apparently by ice which (he says) came through 
the gorge of Tarbert from the west. 
At this gorge, he found in the Till, boulders of a close-grained horn- 
blende rock, doubtless (as he says) portions of a rock of identical 
character situated a few hundred yards to the westward. 
The Professor adds, that as this crystalline rock is very marked 
and unmistakable, he regarded it as unimpeachable evidence of the 
course of the ice through the gorge. 
4. Scalpa was next visited, — an island half a mile or so off the 
east coast of Harris. Here a granite boulder was “ found butted up 
on its east side against the rocky steps of a knoll of gneiss rocks.” 
A sketch of this boulder is given in the Report. With refer- 
ence to the direction of transport, Professor Heddle mentions that 
the same rock of which the boulder is composed forms a bed in a 
high cliff on the mainland of Harris to the 1ST.W. 
5. The Shiant islands, which were next examined, are three in 
number. They also are off the east coast of Harris, about twenty 
miles to the NjE. of Tarbert. 
On the surface of these islands, which are of basalt, no foreign 
erratics of any size were found. But on the shore of two of these 
islands, he found blocks of conglomerate and Cambrian sandstone, 
which had probably come from near Stornoway, about 30 miles to 
the north, where these rocks are in situ. 
The Professor saw in the two largest islands, which lie N. and S. 
of each other, that some agent — it might be ice — had passed over 
them from the west, smoothing them, and pushing fragments of 
the trap rock towards the east. But he observed particularly that 
there was no such smoothing on the third island lying to the 
east ; and the only explanation of this fact which occurred to him 
was, that the third island, being much lower in level than the other 
two, the ice may have passed over, without touching it — an ex- 
planation suggesting the agency of floating ice. 
6. The next island visited was Skye , but the Professor was able only 
to examine the 'N. and N.E. portions, viz., from Aird Point to Portree. 
