turb the received notions as to this formation.

In a portion of it called the Drift, where boulders, gravel, and sand are huddled in masses, seemingly by waters now extinct, some pieces of flint have been found, which, although they can hardly be said to have a shape, have yet an appearance which no known natural force could have communicated to them. They appear, in fact, to have been chipped, and this is maintained to be sufficient evidence that they have passed through the hands of man. No such discoveries have been made in Scotland. True, in some of the great haugh flats, as in that where Glasgow stands, and the carse-lands on the Forth and Tay, human bones have been found, a harpoon or spear made of bone, and the remains of several canoes or primitive vessels. But the existence of these can be accounted for by a phenomenon to which such a district is any day liable-a change in the course of the stream passing through it. Hence there is no necessity for believing these ancient vessels to have sailed on waters which, from some great geological change, have ceased to exist. Roman remains stand on this diluvial formation-so do the stone circles, barrows, and other monuments supposed to belong to some age indefinitely older than the Roman invasion.' In Scotland we are thus at present clear of the diffi

1 The flat district lying between the Sound of Jura and Lochawe, perforated by the Crinan Canal, is perhaps one of the best fields for the observation of this phenomenon, as it is still in a state of nature, or but recently brought in, while most of the other land of the same kind is the oldest tilled land in the country. The aspect of this piece of country is as if extinct waters covering it had once joined Lochawe to the sea. It is quite level, with a few rocks and small hills starting abruptly out of it like islands. Its surface is thickly strewn with the stones called Druidical, standing by themselves and in circles-along with large barrows and other remains of unknown antiquity.

culty of accounting for man and his ways, as under geological conditions different from the present.

The geology of Scotland runs through the entire gamut of the variations in the received systems of geology. There runs north and south an axis of the primitive unstratified rocks, cropping forth here and there from Caithness to Kirkcudbright, in granite, porphyry, and felspar. On its flanks, or covering it, are those stratified rocks which are supposed to have been roasted by proximity to this mass in its molten state, and these form the large districts of gneiss and schist which make the greater portion of the Highlands, and give character to its scenery, the gneiss tending to undulation, and thus causing the monotonous flat hills and shallow valleys of the central Highlands, while the lamular and horny character of the schist comes forth in the rugged and grotesque spikes of the Trosachs and other tourist districts. An articulation of mountains of a different class, because sedimentary in their structure, carries the mountain-chain to the English border. South of the Tay, to the east and the west spreads a broad cake of the later mechanical or unaltered sedimentary formations, rich in coal and iron, and often pierced by traps and other irruptive rocks attributed to recent plutonic action. It is at the very northern extremity of the island-on the coastedge of Sutherland, in small patches among the Western Isles, and in a margin of the south-west coast-that we find the lias, oolite, and other recent formations, which, like the same strata in the south of England, abound in large and emphatic organic remains. Lastly, here and there, both in the mountains and the flatter districts, are tracts of the diluvium already referred to.

The map at once shows Scotland to be a country well adapted for union and defence. It has a backbone in the range of mountains, open to retreat from all quarters. There are few parts of the country more than fifty miles distant from the sea on the one side and from mountains on the other. On studying these conditions, one sees how it might very well be the land where the concentrating power of geographical conditions forced two uncongenial races of different language and temperament into combination. The mountain districts, all but a few diluvial valleys, must have ever been unproductive. The wild animals among them must have been very few, and they could only have been inhabited to any extent at the times when there were cultivated lands at no great distance, which their inhabitants could pillage. The rest of the country has none of the natural fertility that generally attracts indolent and unadventurous inhabitants, but it is extremely rich in the raw materials of active industry. Coal, iron, lime, and building-stone abound; there is much water-power for machinery, and the sea is accessible for commerce and fishing. There is scarcely any natural soil save the haughs or carses on the border of the rivers; but the traps, limestones, and other minerals, are found valuable chemical elements in the soils created by culture. Lead, copper, and nickel are found in considerable quantities. Silver is still extracted from the lead-mines, and gold has been found in the quartz, but not in sufficient quantity to pay the cost of working it. For minor natural productions there are nodules of agate and veins of onyx in the trap rocks, and finely-coloured rock crystals in the granite mountains. Just one stone coming up to the rank of a

gem has been found in the Cairngorm Mountains-it is the beryl, or aqua-marine. It has affected the history of the ornamental arts in Scotland, too, that pearls have been found in abundance in the rivers. In connection with the discovery of ancient weapons, it will be found to be interesting to know whether the flint is native to Scotland. The Chalk formation, to which it belongs, is wanting; but in the north-eastern districts flints have been found in considerable abundance, and it is thence inferred that chalk had been in existence, and had disappeared through some wasting process.

It is only in the strips of diluvial ground already spoken of that stone is not found close at hand. A country of such geological character has more than the ordinary opportunities for preserving the works raised by the people, at periods when they had not advanced beyond the use of the readiest materials. Accordingly, Scotland is rich in what are called the remains of

primitive inhabitancy. In the timbered plains or morasses which make so great a share of Northern Europe, there may have been fought great contests, calling into existence many defensive works, which have all disappeared from the face of the earth ages ago. In Scotland such things have had a permanency.

The country is crowded with hill-fortresses, small and great; they may be counted by hundreds. They consist of mounds of earth or stone, or both, running round the crests of hills. Only those most remarkable for their size or other specialties need here be noticed. In the northern part of Forfarshire, just where the Grampians begin to swell into mountains, there are two conical detached hills, called the White and the Black Caterthun. The one has its name evidently

from the rings of white stone which are seen to encircle it; the other is termed black by way of contrast, because the turf rings surrounding it make no variation on the natural dark hue of a Scots heather hill. The White Caterthun is a fortress of four concentric circles of stone, the innermost of which has a diameter of some eighty paces. Perhaps the best conception of the greatness of this work may be taken from the simple description of the Engineer officer, who, in his search for the vestiges of Roman camps, was amazed to discover this remnant of native engineering. "The most extraordinary thing that occurs in this British fort is the dimensions of the rampart, composed entirely of large loose stones, being at least twenty-five feet thick at top, and upwards of one hundred at bottom, reckoning quite to the ditch, which seems, indeed, to be greatly filled up by the tumbling-down of the stones. The vast labour that it must have cost to amass so incredible a quantity, and carry them to such a height, surpasses all description. A single earthen breastwork surrounds the ditch; and beyond this, at the distance of about fifty yards on the two sides, but seventy on each end, there is another double intrenchment of the same sort running round the slope of the hill. The intermediate space probably served as a camp for the troops, which the interior post, from its smallness, could only contain a part of. The entrance into this is by a single gate on the east end; but opposite to it there are two leading through the outward intrenchment, between which a work projects, no doubt for containing some men posted there as an additional security to that quarter.'

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1 Roy's Military Antiquities, 205-6.