To answer his question as it might best be answered would be most briefly and vividly done by a true poet. I can only pretend to present the mere facts, but even such a presentation in the driest and baldest way cannot conceal their inherent marvellous interest.
Those grey bosses of rock that rise out of Loch Maree and form the base and outworks of Slioch are portions of the very oldest known land-surface of Europe, as incalculably more ancient than the rest of the Highlands, as the Highlands in turn are more ancient than the Alps or the Apennines. Their heights and hollows existed before the red sandstones were laid down. To this day, you can walk along the shore-line of the vanished lake or sea in which these sandstones accumulated, and can mark how hill after hill, and valley after valley, sank under its waters, and were buried beneath its quietly gathering sand and shingle. That primeval land-surface, slowly settling down, came at last to lie under several thousand feet of such sediment. Long subsequently, after the sand, hardened into sandstone and the gravel, consolidated into conglomerate, had been partially raised out of water, came the time when the white rock of Ben Eay and Craig Roy gathered as fine white sand on the sea-bottom. Some beds of this compacted sand are filled with millions of the burrows of sea-worms that lived in it, and higher up come bands of shale and limestone containing here and there trilobites, shells, corals, sponges and other organisms belonging to an age anterior to that of even the very oldest fossiliferous rocks of most of the rest of Britain. These sheets of marine sediment point to a period when there were no hills in north-west Scotland, for the primeval heights still lay deeply buried, and a shoreless sea spread far and wide over the region.
At length after a vast interval of time came an epoch of gigantic terrestial disturbance, when north-western Europe, from the North Cape to the south of Ireland, was convulsed; when the solid crust of the earth was folded, crumpled, and fractured, until its shattered rocks, crushed and kneaded together, acquired the crystalline characters which they now display. In the course of these tremendous displacements (to which there is no parallel in the later geological history of this country) huge slices of the earth's crust, many hundreds of feet thick and many miles long, were wrenched asunder and pushed bodily westwards, sometimes for a distance of ten miles. By this means portions of the oldest rocks of the region were torn off and planted on the top of the youngest. The whole country, thus broken up, underwent many subsequent mutations, and was finally left to be gradually worn down by the various agents that have carved the surface of the land into its present shape.
Our three groups of rock, so distinctly marked out in the landscape, thus record three successive and early chapters in the long history by which the topography of the Scottish Highlands has been brought into its existing form. Knowing what is their story, we find that every crag and scar acquires a new meaning and interest. Past and present are once more brought into such close and vivid union that while we gaze at the landscape as it stands now, its features seem to melt away into visions of what it has once been. We can in imagination clothe it with its ancient pine-forests through which the early Celtic colonists hunted the urus, the wild boar, the wolf, the brown bear, and the reindeer. We can fill up the valley with the stately glacier which once stretched along its hollow and went out to sea. We can dimly conceive the passage of the long ages of persistent decay by which mountain and glen, corry and cliff were carved into the forms which now so delight our eye.
In a memorable and often-quoted passage, Johnson wrote, 'To abstract the mind from all local emotion would be impossible, if it were endeavoured, and would be foolish if it were possible. Whatever withdraws us from the power of our senses, whatever makes the past, the distant, or the future predominate over the present, advances us in the dignity of thinking beings.'[19] If this be a just judgment, surely we may further maintain that whatever heightens our interest in the landscapes around us, whatever quickens the imagination by presenting new views of what has long been familiar, whatever deepens our reverence by teaching us to recognise the proofs of that long orderly progress through which the land has been fashioned for our use, undoubtedly raises us in the dignity of thinking beings, stimulates the emotional side of our nature, and furnishes abundant material for the exercise of the literary and artistic faculties. Science even in her noblest inspirations, is never poetry, but she offers thoughts of man and nature which the poet, in the alembic of his genius, may transmute into purest poetic gold.
But we have lingered by the side of this northern lake, with its noble curtain of mountains, and the sun meanwhile has sunk in a glory of flame beneath the faint outline of the Hebrides; the last flush of crimson has faded from the sky and the twilight is deepening into night adown the valley. In leaving the scene, if I have succeeded in showing how we have it in our own power to quicken the influence of scenery on the imagination, we may I trust take with us the full conviction that there is no landscape so fair which may not be endued with fresh interest if the light of scientific discovery be allowed to fall upon it. Bearing this light with us in our wanderings, whether at home or abroad, we are gifted, as it were, with an added sense and an increased power of gathering some of the purest enjoyment which the face of Nature can yield.
FOOTNOTES:
[7] Fortnightly Review, April, 1893.
[8] Herodotus, vii. 129.