and inanimate nature. He has ameliorated the climate, and by so doing has affected the agencies of waste that are wearing down the surface of the land. The rivers are now, probably, a good deal less in size than they were even in the days of the Romans, and there may be fewer runnels and streamlets. The old mosses acted as vast sponges, collecting the rain that fell upon them or soaked into them from the neighbouring slopes, and feeding with a constant supply the brown peaty rivulets that carried their surplus waters to the lower grounds. The evaporation from these wide swampy flats could not but be extensive, and the rainfall was thus, in all likelihood, proportionately great. But the clearing away of the forests and of the peat-mosses has removed one chief source alike of the rivulets and of the rain. The amount of denudation by the combined influence of rain and streams might accordingly be supposed to be less, on the whole, than it was eighteen hundred years ago. But we must bear in mind that the extent to which draining has now been carried all over the country has had the effect of allowing the rain to run off more easily into the rivers, which consequently swell and fall again more rapidly than they used to do. Floods or 'spates,' though the rainfall may be the same or less, have thus a tendency to be more sudden and violent than formerly, and hence the increased amount of erosion performed by rivers in flood may be more than an equivalent for the diminution of their ordinary state.

Among the plants and animals of the country, too, traces of the influence of man's interference are everywhere apparent. He has altered the character of the vegetation over wide districts, driving away plants of one kind, such as the heaths, to put in their stead those of another type, like the cereals, thus materially modifying the aspect of the country. The gradual change of climate superinduced by him must also

have affected the vegetation of the country; some herbs grow now more abundantly than they formerly did; or they may now be able to flourish at a higher level than of old. Others, to which the change has been unfavourable, may have been greatly thinned in numbers, and even extirpated altogether. In like manner, the coming of man has worked mighty transformations in the animal world. Over and above the extirpation of the beasts of the forest, and the introduction of foreign forms into the country, he has waged incessant war against those which he considers injurious to his interest. He has thus altered the natural proportion of the different species to each other, and introduced a new element into the universal struggle for existence.' No species, whether of plants or of animals, can notably increase or diminish in number without, of course, thereby exerting an influence upon its neighbours. boundless field of inquiry opens out to us. has not been a mere solitary fact, nor have the alterations which he has effected been confined merely to the relations that subsist between himself and nature. He has set in motion a series of changes which have reacted on each other in countless circles, both through the organic and the inorganic world. Nor are they confined to the past; they still go on; and, as years roll away, they must produce new modifications and reactions, the stream of change ever widening, carrying with it man himself, from whom it took its rise, and who is yet in no small degree involved in the very revolutions which he originates.

And here a Man's advent

CHAPTER XIX

INFLUENCE OF THE PHYSICAL FEATURES OF SCOTLAND

UPON THE PEOPLE

THE Connection between the physical features of a country and the history and temperament of its people has hardly received, either from historians or geologists, the attention which it deserves. Though not obtrusive, it is real and close, and amid other and more potent influences has never ceased to play its part in the moulding of national character and progress. It may be seen (1) in the distribution and migration of races; (2) in the historical development of a people; (3) in industrial and commercial progress; and (4) in national temperament and literature. I propose briefly to refer to the illustrations which these questions receive in Scotland.1

(1.) The fundamental distinction between highlands and lowlands has had a powerful effect on the wanderings and ultimate grouping of the different races of mankind. Nowhere can the influence of this topographical contrast be better ob

A few passages in this chapter have already appeared in an essay on 'The Geological Influences which have affected the Course of British History,' which is included in my Geological Sketches at Home and Abroad, p. 353.

served than in Scotland. The Scottish Highlands, sharply defined against the Lowland plains, and washed around their other sides by the stormy Atlantic Ocean, offered in rude times a wild and almost inaccessible asylum against invasion. There the original Gaelic population has been able to maintain itself, while wave after wave of hostile immigrants has broken against the bases of the hills. The Cymri, who came after the Gaels, possessed themselves of the southern part of the country; but they do not seem ever to have advanced beyond the limits of their Strathclyde territories. The Romans carried their conquests up to the borders of the Highlands, but there was nothing among those dark mountains to invite them farther. They marched into the northern wilds, indeed, but it was rather for vainglory and to punish their savage assailants than with the view of permanent occupation. And so tracing their wall and planting their forts across the narrowest part of the island, they were content to let the Highlanders keep their fastnesses.

When the next wave of conquest brought successive hordes of Norsemen and Danes from beyond the sea to our shores, the same physical features, which had guided and limited the march of the southern invaders, once more set bounds to the progress of the Vikings from the north.

The lowlands of the northern counties and of the Midland Valley lay open to the war-boats of the pirates, and there, driving out or absorbing the Celtic population, the Teutons. firmly planted themselves. But they never pushed their way into the mountains. Down to this day, in spite of the slow, but unceasing diffusion and amalgamation of the races, the geological boundary between the rough ground of the crystalline schists on the one hand, and the drift-covered plains of Old Red Sandstone on the other, is still in great measure the boundary of the Gaelic-speaking and English

speaking population. On the Old Red Sandstone, we hear only English, often with a northern accent, or with some northern words that seem to remind us of the Norse blood which flows in the veins of these hardy fisherfolk and farmers. We there come upon groups of villages and towns. The houses, though often poor and dirty, are for the most part solidly built of hewn stone and mortar, with well-made roofs of thatch, slate, or flagstone. The fuel in ordinary use

is coal, brought by sea from the south.

But no sooner do we advance within the Highland districts of the crystalline schists than all the human associations of the ground, as well as its physical aspect, appear changed. Gaelic is now the vernacular tongue. There are few or no villages. The houses built of boulders gathered from the soil, and held together with mere clay or earth, are covered with frail roofs of ferns, straw, or heather, kept down by stone-weighted ropes of the same materials. Fireplaces and chimneys are luxuries not yet universally adopted, and the pungent blue smoke from fires of peat or turf finds its way out by door and window, or beneath the begrimed rafters. The contrast of geological structure and scenery which allowed the Teutonic invaders to drive the older Celtic people from the coast-line, but prevented them from advancing inland, has sufficed during all the subsequent centuries to keep the two races apart.

When Engle and Norsemen landed on the eastern side of the country, the broad selvage of low ground between them and the dark mountains in the distance offered them sites for their new homesteads, which, by degrees, were planted all along the coast within touch of each other. But down the sea-board of the Western Highlands lay no such convenient plain. There the mountains shoot up from the edge of the sea, and though at the heads of the long, deep,