29. Stand for half an hour beside the fall of Schaffhausen, on the north side, where the rapids are long, and watch how the vault of water first bends unbroken, in pure polished velocity, over the arching rocks at the brow of the cataract, covering them with a dome of crystal twenty feet thick, so swift that its motion is unseen except when a foam globe from above darts over it like a falling star; and how the trees are lighted above it under all their leaves,[19] at the instant that it breaks into foam; and how all the hollows of that foam burn with green fire like so much shattering chrysoprase; and how, ever and anon startling you with its white flash, a jet of spray leaps hissing out of the fall, like a rocket, bursting in the wind and driven away in dust, filling the air with light; and how through the curdling wreaths of the restless crashing abyss below, the blue of the water, paled by the foam in its body, shows purer than the sky through white rain-cloud, while the shuddering iris stoops in tremulous stillness over all, fading and flushing alternately through the choking spray and shattered sunshine, hiding itself at last among the thick golden leaves which toss to and fro in sympathy with the wild water,--their dripping masses lifted at intervals, like sheaves of loaded corn, by some stronger gush from the cataract, and bowed again upon the mossy rocks as its roar dies away,--the dew gushing from their thick branches through drooping clusters of emerald herbage, and sparkling in white threads along the dark rocks of the shore, feeding the lichens, which chase and chequer them with purple and silver. [19] Well noticed. The drawing of the fall of Schaffhausen, which I made at the time of writing this study, was one of the very few, either by other draughtsmen or myself, which I have seen Turner pause at with serious attention.