twenty thousand feet in height, six or seven miles over in illuminated surface, furrowed by a thousand colossal ravines, torn by local tempests into peaks and promontories, and changing its features with the majestic velocity of a volcano."--(Vol. i. p. 228.) The forms of clouds, it seems, are worth studying: after reading this, no landscape-painter will be disposed, with hasty slight invention, to sketch in these "_mountains_" of the sky. Here is his description, or part of it, first of falling, then of running water. With the incidental criticism upon painters we are not at present concerned:-- "A little crumbling white or lightly-rubbed paper will soon give the effect of indiscriminate foam; but nature gives more than foam--she shows beneath it, and through it, a peculiar character of exquisitely studied form, bestowed on every wave and line of fall; and it is this variety of definite character which Turner always aims at, rejecting as much as possible everything that conceals or overwhelms it. Thus, in the Upper Fall of the Tees, though the whole basin of the fall is blue, and dim with the rising vapour, yet the attention of the spectator is chiefly directed to the concentric zones and delicate curves of the falling water itself; and it is impossible to express with what exquisite accuracy these are given. They are the characteristic of a powerful stream descending without impediment or break, but from a narrow channel, so as to expand as it falls. They are the constant form which such a stream assumes as it descends; and yet I think it would be difficult to point to another instance of their being rendered in art. You will find nothing in the waterfalls, even of our best painters, but springing lines of parabolic descent, and splashing and shapeless foam; and, in consequence, though they may make you understand the swiftness of the water, they never let you feel the weight of it: the stream, in their hands, looks _active_, not _supine_, as if it leaped, not as if it fell. Now, water will leap a little way--it will leap down a weir or over a stone--but it _tumbles_ over a high fall like this; and it is when we have lost the parabolic line, and arrived at the catenary--when we have lost the spring of the fall, and arrived at the _plunge_ of it--that we begin really to feel its weight and wildness. Where water takes its first leap from the top, it is cool and collected, and uninteresting and mathematical; but it is when it finds that it has got into a scrape, and has farther to go than it thought for, that its character comes out; it is then that it begins to writhe and twist, and sweep out, zone after zone, in wilder stretching as it falls, and to send down the rocket-like, lance-pointed, whizzing shafts at its sides sounding for the