OF THE MATERIALS OF MOUNTAINS:—FOURTHLY, COMPACT COHERENTS.

§ 1. This group of rocks, the last we have to examine, is, as far as respects geographical extent and usefulness to the human race, more important than any of the preceding ones. It forms the greater part of all low hills and uplands throughout the world, and supplies the most valuable materials for building and sculpture, being distinguished from the group of the slaty coherents by its incapability of being separated into thin sheets. All the rocks belonging to the group break irregularly, like loaf sugar or dried clay. Some of them are composed of hardened calcareous matter, and are known as limestone; others are merely hardened sand, and are called freestone or sandstone; and others, appearing to consist of dry mud or clay, are of less general importance, and receive different names in different localities.

§ 2. Among these rocks, the foremost position is, of course, occupied by the great group of the marbles, of which the substance appears to have been prepared expressly in order to afford to human art a perfect means of carrying out its purposes. They are of exactly the necessary hardness,—neither so soft as to be incapable of maintaining themselves in delicate forms, nor so hard as always to require a blow to give effect to the sculptor's touch; the mere pressure of his chisel produces a certain, effect upon them. The color of the white varieties is of exquisite delicacy, owing to the partial translucency of the pure rock; and it has always appeared to me a most wonderful ordinance,—one of the most marked pieces of purpose in the creation,—that all the variegated kinds should be comparatively opaque, so as to set off the color on the surface, while the white, which if it had been opaque would have looked somewhat coarse (as, for instance, common chalk does), is rendered just translucent enough to give an impression of extreme purity, but not so translucent as to interfere in the least with the distinctness of any forms into which it is wrought. The colors of variegated marbles are also for the most part very beautiful, especially those composed of purple, amber, and green, with white; and there seems to be something notably attractive to the human mind in the vague and veined labyrinths of their arrangements. They are farther marked as the prepared material for human work by the dependence of their beauty on smoothness of surface; for their veins are usually seen but dimly in the native rock; and the colors they assume under the action of weather are inferior to those of the crystallines: it is not until wrought and polished by man that they show their character. Finally, they do not decompose. The exterior surface is sometimes destroyed by a sort of mechanical disruption of its outer flakes, but rarely to the extent in which such action takes place in other rocks; and the most delicate sculptures, if executed in good marble, will remain for ages undeteriorated.

§ 3. Quarries of marble are, however, rare, and we owe the greatest part of the good architecture of this world to the more ordinary limestones and sandstones, easily obtainable in blocks of considerable size, and capable of being broken, sawn, or sculptured with ease; the color, generally grey, or warm red (the yellow and white varieties becoming grey with age), being exactly that which will distinguish buildings by an agreeable contrast from the vegetation by which they may be surrounded.

To these inferior conditions of the compact coherence we owe also the greater part of the pretty scenery of the inhabited globe. The sweet winding valleys, with peeping cliffs on either side; the light, irregular wanderings of broken streamlets; the knolls and slopes covered with rounded woods; the narrow ravines, carpeted with greensward, and haunted by traditions of fairy or gnome; the jutting crags, crowned by the castle or watch-tower; the white sea-cliff and sheep-fed down; the long succession of coteau, sunburnt, and bristling with vines,—all these owe whatever they have of simple beauty to the peculiar nature of the group of rocks of which we are speaking; a group which, though occasionally found in mountain masses of magnificent form and size, is on the whole characterized by a comparative smallness of scale, and a tendency to display itself less in true mountains than in elevated downs or plains, through which winding valleys, more or less deep, are cut by the action of the streams.

§ 4. It has been said that this group of rocks is distinguished by its incapability of being separated into sheets. This is only true of it in small portions, for it is usually deposited in beds or layers of irregular thickness, which are easily separable from each other; and when, as not unfrequently happens, some of these beds are only half an inch or a quarter of an inch thick, the rock appears to break into flat plates like a slaty coherent. But this appearance is deceptive. However thin the bed may be, it will be found that it is in its own substance compact, and not separable into two other beds; but the true slaty coherents possess a delicate slatiness of structure, carried into their most minute portions, so that however thin a piece of them may be, it is usually possible, if we have instruments fine enough, to separate it into two still thinner flakes. As, however, the slaty and compact crystallines, so also the slaty and compact coherents pass into each other by subtle gradations, and present many intermediate conditions, very obscure and indefinable.

§ 5. I said just now that the colors of the compact coherents were usually such as would pleasantly distinguish buildings from vegetation. They are so; but considered as abstract hues, are yet far less agreeable than those of the nobler and older rocks. And it is to be noticed, that as these inferior rocks are the materials with which we usually build, they form the ground of the idea suggested to most men's minds by the word "stone," and therefore the general term "stone-color" is used in common parlance as expressive of the hue to which the compact coherents for the most part approximate. By stone-color I suppose we all understand a sort of tawny grey, with too much yellow in it to be called cold, and too little to be called warm. And it is quite true that over enormous districts of Europe, composed of what are technically known as "Jura" and "mountain" limestones, and various pale sandstones, such is generally the color of any freshly broken rock which peeps out along the sides of their gentler hills. It becomes a little greyer as it is colored by time, but never reaches anything like the noble hues of the gneiss and slate; the very lichens which grow upon it are poorer and paler; and although the deep wood mosses will sometimes bury it altogether in golden cushions, the minor mosses, whose office is to decorate and chequer the rocks without concealing them, are always more meagrely set on these limestones than on the crystallines.

§ 6. I never have had time to examine and throw into classes the varieties of the mosses which grow on the two kinds of rock, nor have I been able to ascertain whether there are really numerous differences between the species, or whether they only grow more luxuriantly on the crystallines than on the coherents. But this is certain, that on the broken rocks of the foreground in the crystalline groups the mosses seem to set themselves consentfully and deliberately to the task of producing the most exquisite harmonies of color in their power. They will not conceal the form of the rock, but will gather over it in little brown bosses, like small cushions of velvet made of mixed threads of dark ruby silk and gold, rounded over more subdued films of white and grey, with lightly crisped and curled edges like hoar frost on fallen leaves, and minute clusters of upright orange stalks with pointed caps, and fibres of deep green, and gold, and faint purple passing into black, all woven together, and following with unimaginable fineness of gentle growth the undulation of the stone they cherish, until it is charged with color so that it can receive no more; and instead of looking rugged, or cold, or stern, as anything that a rock is held to be at heart, it seems to be clothed with a soft, dark leopard skin, embroidered with arabesque of purple and silver. But in the lower ranges this is not so. The mosses grow in more independent spots, not in such a clinging and tender way over the whole surface; the lichens are far poorer and fewer; and the color of the stone itself is seen more frequently; altered, if at all, only into a little chiller grey than when it is freshly broken. So that a limestone landscape is apt to be dull, and cold in general tone, with some aspect even of barrenness. The sandstones are much richer in vegetation: there are, perhaps, no scenes in our own island more interesting than the wooded dingles which traverse them, the red rocks growing out on either side, and shelving down into the pools of their deep brown rivers, as at Jedburgh and Langholme; the steep oak copses climbing the banks, the paler plumes of birch shaking themselves free into the light of the sky above, and the few arches of the monastery where the fields in the glen are greenest, or the stones of the border tower where its cliffs are steepest, rendering both field and cliff a thousandfold more dear to the heart and sight. But deprived of associations, and compared in their mere natural beauty with the ravines of the central ranges, there can be no question but that even the loveliest passages of such scenery are imperfect and poor in foreground color. And at first there would seem to be an unfairness in this, unlike the usual system of compensation which so often manifests itself throughout nature. The higher mountains have their scenes of power and vastness, their blue precipices and cloud-like snows: why should they also have the best and fairest colors given to their foreground rocks, and overburden the human mind with wonder; while the less majestic scenery, tempting us to the observance of details for which amidst the higher mountains we had no admiration left, is yet, in the beauty of those very details, as inferior as it is in scale of magnitude?

§ 7. I believe the answer must be, simply, that it is not good for man to live among what is most beautiful;—that he is a creature incapable of satisfaction by anything upon earth; and that to allow him habitually to possess, in any kind whatsoever, the utmost that earth can give, is the surest way to cast him into lassitude or discontent.

If the most exquisite orchestral music could be continued without a pause for a series of years, and children were brought up and educated in the room in which it was perpetually resounding, I believe their enjoyment of music, or understanding of it, would be very small. And an accurately parallel effect seems to be produced upon the powers of contemplation, by the redundant and ceaseless loveliness of the high mountain districts. The faculties are paralyzed by the abundance, and cease, as we before noticed of the imagination, to be capable of excitement, except by other subjects of interest than those which present themselves to the eye. So that it is, in reality, better for mankind that the forms of their common landscape should offer no violent stimulus to the emotions,—that the gentle upland, browned by the bending furrows of the plough, and the fresh sweep of the chalk down, and the narrow winding of the copse-clad dingle, should be more frequent scenes of human life than the Arcadias of cloud-capped mountain or luxuriant vale; and that, while humbler (though always infinite) sources of interest are given to each of us around the homes to which we are restrained for the greater part of our lives, these mightier and stranger glories should become the objects of adventure,—at once the cynosures of the fancies of childhood, and themes of the happy memory, and the winter's tale of age.