66 MR DAVID RUSSELL ON 
a remarkably fine display of geological phenomena within 
a short radius of the village. Loch Maree itself lies over a 
zone of weakness—a great fault which runs parallel to 
the strike of the Hebridean gneiss. The rocks on the south 
side of the loch have been let down by a south-west 
downthrow of considerable magnitude. 
The outstanding features of the surface vary in accordance 
with the structure of the rocks of which they are composed. 
The order of succession of the rocks from below, upward, is— 
gneiss, Torridon sandstone, and Cambrian quartzite. 
On the north side of the loch, Beinn Airdh Charr, Beinn 
Lair, and the base of Sloch are almost wholly gneiss. 
Slioch itself is chiefly composed of Torridon sandstone, 
which rock also covers the south-east shoulder of the 
mountain. It lies in nearly horizontal layers and covers 
up the ancient land-surface of the gneiss, which is gradually 
being re-exposed as the overlying strata is removed by the 
ordinary denuding forces. 
On the south side of the loch the Torridon rocks extend 
westwards beyond Talladale, and the islands of Loch Maree 
are Torridonian. Just opposite the islands, across the line 
of fault, the north shore of the loch is gneiss, and it 
rises almost perpendicularly to a height of fully 1000 feet, 
then slopes up to the summit of Beinn Lair. 
Returning to the south side of the loch, overlying the 
Torridon rocks is the quartzite which gives to the peaks 
of the Ben Eay range their characteristic snow-white, sugar- 
loaf appearance. 
Opposite Kenlochewe a bold escarpment rises to a height 
of over 2200 feet, and exhibits one of the thrust planes that 
extend for many miles to the north and south. Combined 
with other earth-movements, these thrust planes have thrown 
the strata into such confusion that for many years geologists 
were baffled in their attempts to unravel the problems of the 
succession of these rocks. 
Passing on to a much later period, we note the evidence 
of the Glacial Epoch, when this part of the country was 
covered with ice to the depth of, perhaps, nearly 3000 feet— 
evidence written everywhere so clearly that even the least 
