Or, again, I seem once more to sit in the balcony of a house that looks out towards Vesuvius. It is late; the sky is clouded, the air is still; a grateful coolness comes up from acre after acre of gardens climbing the steep slope; a fluttering breeze, that seems to have lost his way in the dusk, comes timidly and whimsically past, like Ariel, singing as soft as a far-off falling sea in the great pine overhead, making a little sudden flutter in the dry leaves of the thick creeper; like Ariel comes that dainty spirit of the air, laden with balmy scents and cool dew. A few lights twinkle in the plain below. Opposite, the sky has an added blackness, an impenetrability of shade; but what is the strange red eye of light that hangs between earth and heaven? And, stranger still, what is that phantasmal gleam of a lip of crags high in the air, and that mysterious, moving, shifting light, like a pale flame, above it? The gloomy spot is a rent in the side of Vesuvius where the smouldering heat has burnt through the crust, and where a day or two before I saw a viscid stream of molten liquor, with the flames playing over it, creeping, creeping through the tunnelled ashes; and in the light above is the lip of Vesuvius itself, with its restless furnace at work, casting up a billowy swell of white oily smoke, while the glare of the fiery pit lights up the underside of the rising vapours. A ghastly manifestation, that, of sleepless and stern forces, ever at work upon some eternal and bewildering task; and yet so strangely made am I, that these fierce signal-fires, seen afar, but blend with the scents of the musky alleys for me into a thrill of unutterable wonder. There are hundreds of such pictures stored in my mind, each stamped upon some sensitive particle of the brain, that cannot be obliterated, and each of which the mind can recall at will. And that, too, is a fact of surpassing wonder: what is the delicate instrument that registers, with no seeming volition, these amazing pictures, and preserves them thus with so fantastic a care, retouching them, fashioning them anew, detaching from the picture every sordid detail, till each is as a lyric, inexpressible, exquisite, too fine for words to touch?