CHAP. XLII 
THE BASIC SILLS OF SKYE 
3°5 
to the surface the accompanying 
sills are exposed to view. The 
east coast of the island has 
been classic ground for this part 
of volcanic geology since it 
supplied the materials for 
Macculloeh’s descriptions and 
diagrams. From the mouth 
of Loch Sligachan to Eudha 
Hunjsh, at the north end of 
Skye, a series of sills may be 
traced, sometimes crowning the 
cliffs as a columnar mural escarp- 
ment, sometimes burrowing in 
endless veins and threads through 
the Jurassic rocks. The hori- 
zontal distance to which this 
continuous band of sills extends 
in Skye is not far short of 30 
miles. But it stretches beyond 
the limits of the island. It 
forms the group of islets which 
prolongs the geological structure 
and topographical features of 
Trotternisli for 4 miles further 
to the north-west. It reappears 
10 miles still further on in the 
Shiant Isles. Thus its total 
visible length is fully 40 miles, 
or if we include some outlying; 
sills near the Point of Sleat, to be 
afterwards described, it extends 
over a distance of not less than 
60 miles. From the last outlier 
in Skye to the sills of the Isle of 
Eigg is a distance of only 8 
miles, thence to those of Ardna- 
murchan 1 7 miles, and to those 
of the south coast of Mull 25 
miles. Thus this platform of 
intrusive sheets of the Inner 
Hebrides can be interruptedly 
followed for a space of not less 
than 110 miles. 
Though none of the sills in 
Skye itself attain the dimensions 
VOL. 11 
x 
