The first half is divided into considerations of 'Leaf' and 'Cloud Beauty,' respectively: 'The leaf between earth and man, as the cloud is between man and heaven.' Many fanciful headings are given to the chapters on these subjects. In the 'Earth Veil' Mr. Ruskin discourses in very delicate poetry, of trees and flowers, which form on the surface of the earth a veil of vegetation; 'of strange intermediate being; which breathes, but has no voice; moves, but cannot leave its appointed place; passes through life without consciousness; to death without bitterness; wears the beauty of youth without its passion, and declines to the weakness of age without its regret' Passing on, then, to the 'orders of the leaf,' he arranges plants in two classes,--the TENTED PLANTS, which live on the ground, as lilies, or crawl on the rocks, as lichen and mosses, leading ever an arab life, and so passing away and perishing; and the BUILDING PLANTS, which soar above the earth in the 'architectural edifices we call trees.' And the builders are again curiously subdivided. There are the 'builders with the shield,' with their leaves, shield-shaped, raised above, and sheltering their buds as they rise. Gentle, and pleasant, and conciliatory builders are these, living in pleasant places, and providing food and shelter for man. And there are also the 'builders with the sword,' with sharp-pointed leaves stuck fearlessly out sword fashion, the bud growing amid the points, dwelling in savage places, and of little aid to man, none in the way of food. (They are called 'pines,' we may explain, vernacularly.) Mr. Ruskin then goes on to the 'Bud,' and is at some pains to explain its gradual development and the scheme of its growth. 'Leaves' he explains to be 'broadly divisible into mainsails and studding-sails.' Many diagrams are given explanatory of the leaf system, its form and manner and charm, and the 'laws of deflection, of succession, of resilience,' all fanciful theories arising from the subject, are in turn laid down. In our progress to 'tree-structure,' we come to 'leaf aspects.' Then perhaps the object of this elaborate teaching transpires, and Mr. Ruskin speaks of the 'Pre-Raphaelites who, some years back, began to lead our wondering artists back into the eternal paths of all great art, and showed that whatever men drew at all ought to be drawn accurately and knowingly, not blunderingly nor by guess (leaves of trees among other things),' proceeding to the following curious dictum,--'If you can paint one leaf you can paint the world.' The Pre-Raphaelite laws 'lay stern on the strength of Apelles and Zeuxis, put Titian to thoughtful trouble, are unrelaxed yet, and unrelaxable for ever. Paint a leaf indeed!--the above-named Titian has done it. Corregio, moreover, and Giorgione and Leonardo, very nearly, trying hard. Holbein three or four times, in precious pieces, highest wrought. Raphael, it may be, in one or two crowns of Muse or Sibyl.