J. F. Campbell Collection > On the parallel roads of Lochaber

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D. MILNE HOME ON THE PARALLEL ROADS OF LOCHABER.
So also when this Lake sank to the next "Shelf" or " Eoad " (1066 above
the sea), the surplus waters at that level were discharged by a River Channel
discovei'ed in Glen Glaster, which led to Loch Laggan at a place called the
Rough Burn, and where there is now a great accumulation of materials
having all the appearance of a Delta ; the Delta being exactly at the place
where one would be formed by a river flowing into a lake, at the height of 856
feet above the sea.
So also, with regard to this lake which formed the shelf at 856 feet above
the sea ; there is at the N. E. end of Loch Laggan, at a place called INIukkoul,
an old river channel, which is at the very spot, and level, suitable for
carrying off the surplus waters of the Lake. The River Pattaig now runs
here into Loch Laggan. But this river had evidently, at a former period,
flowed in a diiferent direction, viz., towards the eastward, when the lake
stood about 38 feet higher than at present. Last autumn, I walked up the
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Beds of gravel and sand, from 60 to 70 feet high, in Glen Spean (near Tullocli), cut through
by small streams from the adjoining hills.
banks of this River, and at about a mile from its debouche into Loch Laggan, I
found the old channel, now dry, about 25 feet above the present stream, running
Eastward towards the valley, through which Loch Laggan sent its surplus
waters into Strath Spey,
From the Ordnance Maps, it will be observed, that this last mentioned
.shelf runs along the north side of Glen Spean towards the lower end of the
Glen, whei'e it encircles some rocky knolls. Between these knolls and the hill
called " Craig Dim" there is a summit level or col separating Glen Roy fiom
Glen Spean. As these cols are generally instructive, I examined this one, and
was not disappointed. It is about 20 feet below the level of Shelf 4, and con-