470 PROFESSOR HEDDLE ON THE MINERALOGY OF SCOTLAND. 
It would, therefore, appear that, according to the views of Drs Srerry 
Hunt and Emmons, “the hypersthene rocks of the Western Islands of 
Scotland” are metamorphosed sediments, which underlie, at an enormous 
depth, the Cambrian rocks. 
From such a conclusion I must entirely dissent. 
First, with regard to the rocks as seen in Skye ;—it is to be doubted if any 
one who examined the pillared line of cliff which the so-called “syenite ” forms 
at Ard Bhornis, opposite to Raasay, and the manner in which a sandstone bed 
is involved in it, in Glamich, could come to any conclusion other than that the 
syenite is igneous. 
Its relation to the hypersthene of the Coolins may be studied about the 
middle of Glen Sligican ; where, in the lower slopes of Blaaven, it is seen to be 
continued from Marscow and overlaid by the dark rock, and that in a manner 
very suggestive of denudation of the syenite previous to its envelopment. In 
the steep slopes of the south side of Hart o’ Corry it at first appears to be inter- 
bedded with the darker rocks ; but a closer inspection leads to the conclusion | 
that the small portions of syenite here seen had been connected with the 
large masses on the east side of the glen,—that intruded processes of the 
hypersthene had been thrust into the mass of the older rock, and that the 
cutting out of the strath had severed the original connection. 
As regards its connection with stratified rocks, MAccuLLoc# has pointed out 
that “it is found for a considerable space distinctly incumbent on the limestone | 
and shale of the lias on the shore near Broadford”; that it alters these rocks ;— | 
and it can be seen on the north slopes of Glamich to have broken through, 
and tilted to the north at a high angle, limestones and other rocks of the | 
lias.* 
Passing to the relationship of the very similar rock of Rum, we find the 
north of that island to consist of the same red sandstone as that seen to 
underlie the hypersthene of Garsven; but that red sandstone is in turn, on 
the east coast of the island, underlaid by a series of grits, schists, and cherty 
or hornstone-like beds, of prevailing blue, green, and almost black colours. 
In making two parallel sections of the island; nearly from north to south, 
—namely, from Camusplesaig, past the head of Loch Scresort, up the Allt 
an Eassain, over Scuir na Gillean, and down to the cliffs of Riesval; the second 
from the shore of Scresort, over Halival, Haiskeval, Ben More, and down to | 
Pappadill, we find as follows :— | 
Between the north shore and the head of Scresort we walk for a couple of 
miles over strata, finer, closer, and more sandy than those generally assigned to 
the Cambrian in the north of Scotland; these dip at angles 7° to 10° to the north- | 
* Dupexon and the Author found on the banks of a stream which flows from the north side of 
Glamich loose masses of a volcanic breccia—somewhat similar to that of Rum—but which, among 
fragments of schists and conglomerates, contained many of blue-grey “indurated ” limestone. 

