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

D. MILNE HOME ON THE PARALLEL ROADS OF LOCHABER. G47
Jamieson suggested a theory nearer the truth when he asked " Might not some
of these curious accumulations kno^^^l as E.'^kars, Omr, and Kauns, have been
formed bj' a re-extension of the ice ploughing into the old marine beds, and
forcing them up into long narrow mounds 1 In some regions, these may have
arisen from glaciers terminating in the sea." (Vol. xix. p. 253,)
The only modification I would jDresume to make on this suggestion is, that
instead of glaciers pushing into the sea, and "ploughing the marine beds into
long narrow mounds," I would suj^pose that icebergs, floating through Glen
Spean and gi'ating on Ben Chlinaig and Craig Dhu, might have produced the
long ridgy kaim-like mounds referred to.*
If it be generally agi'eed, that the land was submerged; that the beds of
gravel and sand spread over the coiuitry are manne, and that many of the
boulders (esi^ecially those on hill tops) cannot have been transported except by
floating ice, it seems to me more philosophical to use that acknowledged agency,
for the explanation of other phenomena of the same class (I mean the smoothed
and striated rocks), than resort to a difi^erent agency altogether, whoso existence
is, to say the least, very problematical.
Before concluding, let me shortly state the views I have taken in this
Memoir, both on the local question of the Parallel Eoads, and on the more
general questions into which I have been led.
\st. The valleys in which these roads occur have been occupied by lakes
which subsided from one level to another, as the blockages of the lakes were
worn down.
2nc1. These blockages consisted of detritus (clay, sand, and gravel) which
had been spread over the country when it was submerged, and which filled all
the valleys, up to considerable heights.
onl. The blockages were from time to time worn down, and the materials
composing them removed by the action of rivers, the cutting power of which
would increase as the sea sank from its original high level to its present level.
With regard to the more general question it would appear —
1st. That before these Lochaber Lakes were formed, the whole country
had been under the sea, and that during this submergence, currents with float-
ing ice spread gravel, sand, and clay over what was then the sea-bottom,
filling hollows on what is now the land, and causing rocks to be smoothed and
scratched by the passage and pressure upon them of stones and pebbles.
'2.nd. That the sea prevailed to a height of at least 3000 feet above the
present sea-level.
* It is not unimportant to observe that all these abnormal lines, in Glen Spean and Glen Eoy, are
in level above the highest of the " Parallel Eoads." The sea may have formed these lines at a period
antecedent to the formation of the lakes. The lakes, of course, could not be formed till the sea had
Slink to a level below the highest shelf.
VOL. XXVII. PART IV. 8 H