and terraces. Thousands, I might say millions of miles of this terrace work clothe the hill sides of the south, and this practical necessity affords the best possible practical proof of the truth of the theories which I advocate. When art has thus done her best greenly to flounce nature's garment to the highest, we often see above, long and deep ridges of grey, bald rock without a shrub. Yet, by the chemical action of the atmosphere and by the chemical and mechanical action of rain, this region, the picture of sterility in itself, is a constant source of the most fertile soil for the terraces of the hill side below. That soil does Eternal circle not stop there. It does not stop in the valley below. It does not stop even in the depths of of changes. the sea. 6 From these depths it will be re-elevated. "The Spirit of God' moves through the depths as well as on the face of the waters,' and is present imo tollere de gradu, and each grain of soil which we have traced from the mountain top to the ocean's depth will move for ever in the grand circle of changes contrived by an All-pervading Beneficence. Circle of changes I have called it, but the more proper term would be circle of renovation. And is the term waste quite proper for an action which converts the face of the barren precipice of limestone or granite into rich soil for the production of the most exquisite vegetation, which gives subsistence, and therefore existence, to the noblest of God's creatures? How exquisitely Ovid words the Pythagorean doctrine of perpetual change and renovation: Omnia mutantur; nihil interit. . . Hæc quoque non perstant quæ nos elementa vocamus. tamen omnia fiunt, Ex ipsis et in ipsa cadunt. . . Nec species sua cuique manet, rerumque novatrix Nec perit in tanto quidquam (mihi credite) mundo ; Sed variat faciemque novat; nascique vocatur These are sublime doctrines as regards matter. So is the 'morte carent animæ' as regards the soul. There is,' however, but one step from the sublime to the ridiculous.' And, alas! that the profound philosophers who held these doctrines should have taken the one step beyond the transformation of matter to the ridiculous belief in the transmigration of souls. CHAPTER VI. LYELL ON THE VAL DEL BOVE. Lyell's fifth theory forms the Val del Bove by subsidence. LYELL'S FIFTH THEORY FORMS THE VAL DEL BOVE BY SUB- FOUR different theories for the formation of val- 'Principles,' page, 396., he says: "We cannot ascribe this valley to the action of running water; for if it had been excavated exclusively by that power, its depth would have increased in the descent; whereas, on the contrary, the precipices are most lofty at the upper extremity, and diminish gradually on approaching the lower region of the volcano.' Apply this argument to any other valley. Does the height of the sides of the like all other valleys, by running water. valley of the Mississippi increase, from the Rocky Mountains to the Gulf of Mexico? Does not the height of these sides vary in every part, without any reference whatever to the bed of the valley? The height of the sides of the valley, or their comparative height at different places, has nothing to do with the question. The question is, does the bed of the valley, independently of interruption from modern lava streams, slope continuously It is formed, to the sea? as it does so, there is every presumption that this slope was graduated by water; and it would have required a miracle to have subsided in this form; consider the extent of the continuous descent of the Mississippi from the Rocky Mountains to the Gulf of Mexico, contrasted with the utter irregularity of the sides of the valley, and as Playfair remarks, it is as infinity to unity, that water must have graduated the descent; the irregularity of the sides of mountainous valleys, contrasted with the regularity of their beds, is the very fact which proves that valleys have been formed by the descent of water. For what other agent could have produced these marvellously regular slopes of boundless extent, in the midst of the most thoroughly irregular surfaces? Besides this, if the Val del Bove had subsided, it would have subsided bodily. But there are certain rocks, Finocchio, Lepra, Capra, and Mu H 6 sara, which, owing to their hardness, have resisted disintegration and the wash of rain, and stand abruptly out of the bed of the valley. Of these rocks, Lyell, with much naïveté remarks, ' Almost all the isolated masses in the Val del Bove, such as Capra, Musara, and others, are traversed by dikes, and may, perhaps, have partly owed their preservation to that circumstance, if at least the action of occasional floods has been one of the destroying causes in the Val del Bove; for there is nothing which affords so much protection to a mass of strata against the undermining action of running water as a perpendicular dike of hard rock.' The precipitous sides of the valley are also scored throughout with an infinity of projecting dikes, or veins of injected lava. I call these as witnesses in my favour; for I do not think that subsidence would have left these projections, but disintegration and wash of rain would. 6 Lyell says of them: They consist of harder materials than the strata which they traverse, and therefore waste away less rapidly under the influence of that repeated congelation and thawing to which the rocks in this zone of Etna are exposed.' Now, though Lyell may not agree with me in thinking that these dikes prove the original formation of the valley by waste, he here allows and shows that the prolongation and enlargement of |