It has been said, less wisely than disdainfully, that the chief element of beauty is destroyed when one knows the secret of semblance. Clouds, then, are forfeit in loveliness when one knows the causes of their transformation, their superb illusion? Not so. Has the rose lost in beauty, has she relinquished fragrance, for all that we have learned of her blind roots, the red ichor in her petals, the green pigment in her stem, her hunger that must be fed in coarse earth, her thirst that must be quenched in rain and dew, her desire that must mate with light? Is the rainbow the less a lovely mystery because we know that it is compact of the round, colourless raindrops such as fall upon us in any shower? Is the blue of an unclouded sky the less poignant for us if we know that the sunlight which inhabits it is there, not the yellow or red or suffused white which we discern, but itself an ineffable azure; that, there, the sun itself is not golden or amber or bronze, but violet-blue? I remember it was complained once of something I wrote ... in effect, that cloud was the visible breathing, the suspended breath of earth ... that the simile was as inept as it was untrue. None who knows how cloud is formed will dispute the truth in similitude: as to disillusion, can that be ‘unpoetic’ which is so strange and beautiful a thing? The breath of a little child born in the chill of dawn, the breath of old age fading into the soon untroubled surface of the mirror held against silent lips, the breath of the shepherd on the hills, of the seamen on dark nights under frost-blue stars, the breath of cows on the morning pastures, of the stag panting by the tarn, the breath of woods, of waters, of straths, of the plains, of the brows of hills, the breath of the grass, the breathing of the tremulous reed and the shaken leaf ... are not these the continual vapour of life; and what is cloud but the continual breath of our most deep and ancient friend, the brown earth, our cradle, our home, and our haven?