Mr. Macgillivray’s Account of the Outer Hebrides. 403 
veins is still found accompanying it. As usual, the west coast is 
sandy and little diversified ; the east coast tortuous and rocky. 
Along its eastern coast, and in the channel which separates it from 
North Uist, are numerous islands of the same general nature. This 
channel, as weil as that to the south, is in a great part dry at low 
water, one or more generally shallow stripes being left towards 
either side. ~ 
The next large island is North Uist, so irregular in form that 
description would be wasted upon it. The whole outline of this 
island is singularly tortuous, but more especially that of the south- 
ern and eastern sides. ‘T'wo large arms of the sea enter from the 
east, and intersect the country in a very extraordinary manner; di- 
viding into so many branches, that one might be puzzled to say 
whether land or water predominates in the greater part of it. A 
range of hills, irregular, tortuous, and of little elevation, runs from 
near the western extremity of the island to the Sound of Berneray. 
Hardly any of these attain an elevation of 1500 feet. Another 
range commences at the north-eastern corner, and runs along the 
coast, gradually increasing in height, until it terminates in Heval, 
a hill of about 1500 feet high, at the southern extremity of the is- 
land. This island is in general better covered than these to the 
south ; but in the whole of the eastern part, from the coast to the 
summit of the western range, the soil is exclusively peat, often of 
great depth. The western coasts are more or less sandy ; and at 
a considerable distance off the shore, are seen several inhabited is- 
lands, partly rocky and partly sand-banks, while the intervening 
ground, which is sandy, is for the most part left dry at low water. 
In North Uist the rock is still gneiss. 
But here it becomes necessary to offer some remarks on the fors 
mation to which this name is applied. Gneiss, according to the 
ordinary definition given in geological works, is an aggregate of 
felspar, quartz, and mica, arranged more or less in a laminar form. 
Such in general is the rock of which these islands is composed ; but 
the varieties which it presents are numberless. In many parts the 
ingredients, varying from minutely granular to large concretionary, 
are so arranged that no laminar appearance is perceptible over a 
great extent, although at intervals indications of seams of stratifi- 
eation are seen, and occasionally layers of quartz or mica running 
parallel to these seams present themselves. In fragments of a few 
inches square this reck would correspond precisely to the usual de-~ 
finitions of granite. In other cases the ingredients are very dis- 
tinctly laminar ; and then the beds or strata are equally distinct, 
and generally thin. Intermediate varieties occur, of all degrees. 
In many of these varieties, but especially in the first and most 
common, masses of all sizes up to a surface of several hundred feet 
square present themselves, in which the ingredients are in greatly 
larger concretions than usual, the felspar in particular often being 
several inches in diameter. ‘These masses seem to form part of 
the original constitution of the rock in which they occur. At the 
