of the Rocks of Shetland. S05 
tiler of the same, or of any other rock, consisting altogether 
of Granular Quartz, which is, in fact, a more suitable name for 
it, and, as such, has been adopted by Professor Jameson in 
speaking of rocks of a similar description. The other kind of 
sandstone contains portions, or apparent fragments, either of the 
same or of other rocks, which portions often shew marks of at« 
trition. 
The granular quartz, unmixed with portions of other rocks, 
may be traced from Sumburgh Head to West Voe, where it is 
occasionally associated with a quartz more compact ; when far^ 
ther north at Grutness Voe, its appearance is interrupted by 
the advances of the sea. Thus prevented from tracing the granu- 
lar quartz along the coast in a continued course, we meet with 
it occasionally at the Ness of Sand wick, at Mousa Island where 
it is associated with thin alternating beds of limestone, at Holli- 
ness, and still farther north at the east of Bressay Island, bound- 
ed to the west by a line which may be drawn from the south- 
westerly extremity of the Island to Aithvoe on the north ; and, 
lastly, at the Island of Noss, where, at the channel dividing this 
isle from Bressay, it is superficially covered with a sandstone 
containing large and angular fragments of a rock pf its own de^ 
scription. 
The direction of the strata, as we trace them from the south, 
is very various, but it may, perhaps, be stated generally as ocn 
eurring from N. 30° W. to N. 30° E. 
The dip is generally to the east, at angles of inclination from 
30” to 40^ i occasionally, however, the strata have a westerly 
inclination. 
West of this mass of granular quartz, is a sandstone contain- 
ing fragments of other rocks. This conglomerate sandstone is 
indiscriminately associated with a rock of a similar character, 
but consisting altogether of portions of granite, quartz, and fel- 
spar of various magnitude, from a size the most comminuted 
to that of several pounds weight. These conglomerate rocks 
occupy a narrow tract of country, from Quendal and certain Is- 
lands in the Bay to Bovie Head in the Mainland, including the 
west of Bressay Island. At Fladabister, however, instead of 
granite, portions of gneiss with hornblende appear in a conglo- 
merated state j and in Bressay, occasionally, fragments of clay-slate. 
