§ 2. Has the reader any distinct idea of what clouds are? We had some talk about them long ago, and perhaps thought their nature, though at that time not clear to us, would be easily enough understandable when we put ourselves seriously to make it out. Shall we begin with one or two easiest questions? That mist which lies in the morning so softly in the valley, level and white, through which the tops of the trees rise as if through an inundation--why is _it_ so heavy? and why does it lie so low, being yet so thin and frail that it will melt away utterly into splendor of morning, when the sun has shone on it but a few moments more? Those colossal pyramids, huge and firm, with outlines as of rocks, and strength to bear the beating of the high sun full on their fiery flanks--why are _they_ so light,--their bases high over our heads, high over the heads of Alps? why will these melt away, not as the sun rises, but as he descends, and leave the stars of twilight clear, while the valley vapor gains again upon the earth like a shroud? Or that ghost of a cloud, which steals by yonder clump of pines; nay, which does _not_ steal by them, but haunts them, wreathing yet round them, and yet--and yet, slowly: now falling in a fair waved line like a woman's veil; now fading, now gone: we look away for an instant, and look back, and it is again there. What has it to do with that clump of pines, that it broods by them and weaves itself among their branches, to and fro? Has it hidden a cloudy treasure among the moss at their roots, which it watches thus? Or has some strong enchanter charmed it into fond returning, or bound it fast within those bars of bough? And yonder filmy crescent, bent like an archer's bow above the snowy summit, the highest of all the hill,--that white arch which never forms but over the supreme crest,--how is it stayed there, repelled apparently from the snow--nowhere touching it, the clear sky seen between it and the mountain edge, yet never leaving it--poised as a white bird hovers over its nest? Or those war-clouds that gather on the horizon, dragon-crested, tongued with fire;--how is their barbed strength bridled? what bits are these they are champing with their vaporous lips; flinging off flakes of black foam? Leagued leviathans of the Sea of Heaven, out of their nostrils goeth smoke, and their eyes are like the eyelids of the morning. The sword of him that layeth at them cannot hold the spear, the dart, nor the habergeon. Where ride the captains of their armies? Where are set the measures of their march? Fierce murmurers, answering each other from morning until evening--what rebuke is this which has awed them into peace? what hand has reined them back by the way by which they came?