The Renaissance architects also revived the late Roman manner of employing the column and entablature. They frequently carried on the top of a column a little square pier divided up as the architrave and frieze proper to the column would be divided, and they surmounted it with a cornice which was carried quite round this pier, and from this curious compound pedestal an arch will frequently spring. The classic portico, with pediments, was constantly employed by them; and small pediments over window heads were common. A peculiarity worth mention is the introduction in many Italian palaces of a great crowning cornice, proportioned not to the size of the columns and of the order upon which it rests (if an order be employed), but to the height of the whole building. Much fine effect is obtained by means of this feature; it is, however, better fitted for sunny Italy than for gloomy England, and it is not an unmixed success when repeated in our climate. Towers are less frequently employed than by the Gothic architects, and indeed in Italy the sky-line was less thought of at this period than it was in the middle ages. In churches, towers sometimes occur, nowhere more picturesque than those designed by Sir Christopher Wren for many of his London parish churches. The frequent use of the dome takes the place of the tower both in churches and secular buildings. _Openings._ Openings are both flat-headed and semicircular, occasionally elliptical, but hardly ever pointed. Renaissance buildings may be to some extent divided into those which depend for effect upon window openings, and those which depend chiefly upon architectural features such as cornices, pilasters, and orders. Among the buildings where fenestration (or the treatment of windows) is relied upon the palaces of Venice stand pre-eminent as compositions admirably designed for effect and very successful. In them the openings are massed near the centre of the façade, and strong piers are left near the angles, a simple expedient when once known, and one inherited from the Gothic palaces in that city, but giving remarkable individuality of character to this group of buildings. In roofs, including vaults and domes, we meet with a divergence of practice between Italy and France. In Italy low-pitched roofs were the rule: the parapet alone often formed the sky-line, and the dome and pediment are usually the only telling features of the outline. France, on the other hand, revived a most picturesque feature of Gothic days, namely, the high-pitched roof, employing it in the shape commonly known as the Mansard[30] roof. Nothing adds more to the effectiveness of the great French Renaissance buildings than these lofty terminals.