The façade of the Palazzo Farnese, by Antonio da San Gallo the younger, the grandest of these Roman palaces, again has its wall surfaces unencumbered with orders. The basement is comparatively low, and all three stories are in effect of nearly equal height. The walls are of brick with rusticated quoins of stone, and a rusticated stone portal in relief, of the simple early Florentine type, occupies the centre of the basement. The quoins suggest the influence of the rusticated pilasters on the angles of the Bartolini palace in Florence, and San Gallo has followed Baccio d’Agnolo, the architect of the Bartolini, further by introducing small orders with pediments to frame the windows of the upper stories. But for pilasters he has substituted engaged colonnettes on high pedestals, and in the principal story has made angular pediments alternate with curved ones. This mode of designing doors and windows has since become so common that it generally passes without question of its propriety. It is, however, justifiable only on the principle, universally accepted by the architects of the Renaissance, that structural members may be used for ornamental purposes without any structural meaning or expression in harmony with the character of the building to which they are applied. But this is a principle which finds no support in any thoroughly noble system of architecture--Greek, Byzantine, or Gothic. Structural members may be used properly enough with a primarily ornamental purpose when they have a character in keeping with the real structural system in which they are used. The blind arcades, and shafted archivolts of the portals, of Romanesque and Gothic architecture, are largely of this nature;[93] but to surround the windows of a walled structure, like the Farnese, with columns and entablatures applied to the surface of the wall, is an architectural solecism. A further barbarism occurs in the windows of the top story, which are said to have been designed by Michael Angelo, and the fact that they are like the upper windows of the church of St. Peter lends support to the attribution. These windows of the Farnese are arched, and the crowns of the arches rise above the capitals of the flanking colonnettes so that an entablature resting on these capitals cannot pass over them. Complete entablatures are therefore omitted, entablature blocks being set upon the capitals to support the raking cornices of the pediments (Fig. 63). This makes a bad composition, because the structural system simulated would in reality be an insecure one in consequence of the absence of a tying member which the entablature should form in such a scheme. The eye instinctively feels that the pediment cornices are tending to thrust so as to overthrow the supporting colonnettes. It is true that in the windows of the principal façade (the figure is taken from a window on the side of the building) the cornice of the entablature block is returned against the wall over