24. I wish you especially to notice these points, because the false theory that ornamentation should be merely decorated structure is so pretty and plausible, that it is likely to take away your attention from the far more important abstract conditions of design. Structure should never be contradicted, and in the best buildings it is pleasantly exhibited and enforced: in this very porch the joints of every stone are visible, and you will find me in the Fifth Lecture insisting on this clearness of its anatomy as a merit; yet so independent is the mechanical structure of the true design, that when I begin my Lectures on Architecture, the first building I shall give you as a standard will be one in which the structure is wholly concealed. It will be the Baptistery of Florence, which is, in reality, as much a buttressed chapel with a vaulted roof, as the Chapter House of York;--but round it, in order to conceal that buttressed structure, (not to decorate, observe, but to _conceal_,) a flat external wall is raised; simplifying the whole to a mere hexagonal box, like a wooden piece of Tunbridge ware, on the surface of which the eye and intellect are to be interested by the relations of dimension and curve between pieces of incrusting marble of different colors, which have no more to do with the real make of the building than the diaper of a Harlequin's jacket has to do with his bones. 25. The sense of abstract proportion, on which the enjoyment of such a piece of art entirely depends, is one of the aesthetic faculties which nothing can develop but time and education. It belongs only to highly trained nations; and, among them, to their most strictly refined classes, though the germs of it are found, as part of their innate power, in every people capable of art. It has for the most part vanished at present from the English mind, in consequence of our eager desire for excitement, and for the kind of splendor that exhibits wealth, careless of dignity; so that, I suppose, there are very few now even of our best trained Londoners who know the difference between the design of Whitehall and that of any modern club-house in Pall Mall. The order and harmony which, in his enthusiastic account of the Theater of Epidaurus, Pausanias insists on before beauty, can only be recognized by stern order and harmony in our daily lives; and the perception of them is as little to be compelled, or taught suddenly, as the laws of still finer choice in the conception of dramatic incident which regulate poetic sculpture.