Page:Encyclopædia Britannica, Ninth Edition, v. 2.djvu/498

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440 A R C H I T E C T U R E [MODERN columns of all sizes in all the orders. The entasis of columns is disputed also, some authorities making it consist in preserving the cylinder perfect one-quarter or one-third the height of the shaft from below, diminishing thence in a right line to the top ; while others, following Vitruvius, make the column increase in bulk in a curved line from the base to three-sevenths of its height, and then diminish in the same manner for the remaining four-sevenths, thus making the greatest diameter near the middle. It being difficult to determine among the masters of the Italo-Vitruvian school whose designs of the various orders are to be preferred, we have selected those of Palladio, certainly not for any superior merit they possess, but because ho is more generally esteemed than any other, and because he the most strictly adhered to the precepts of Vitruvius, as far as he could understand them. It should be remarked however, that although Palladio recommended fluting all but the shaft of the Tuscan column, he very seldom fluted columns in his own practice ; and indeed it was the custom of the Italian school not to flute, whatever their doctrine may be to the contrary ; for fluted columns in Italian archi tecture are exceptions to the general practice, Swelled or pillowed friezes are not peculiar to Palladio ; they are more or less common to the works of most of the masters of the same school. Prostyles being almost unknown in Italian architecture, antse are not often required ; but when they are, the meanest succedaneum imaginable is recurred to. Of this Palladio s Villa Capra near Vicenza and Lord Burlington s Palladian villa at Chiswick afford striking examples. Pilasters, however, are very common, so common, indeed, that they may be called pro-columns, as they are often used as an apology for applying an entablature. They are described as differing from columns in their plan only, the latter being round, and the former square ; for they are composed with bases and capitals, are made to support entablatures according to the order to which they belong, and are fluted and diminished with or without entasis, just as columns of the same style would be. When they are fluted, the flutes are limited to seven in number on the face, which, it is said, makes them nearly correspond with the flutes of columns ; and their projection must be one- eighth of their diameter or width when the returns are not fluted ; but if they are, a fillet must come against the wall. Pedestals are not considered by the Italo-Vitruvian school as belonging to the orders, but they may be employed with them all, and have bases and surbases or cornices to corre spond with the order with which they may be associated. The dado of a pedestal must bo a square whose side shall be equal to that of the plinth of the column or pilaster which rests on it, or a parallelogram a sixth or even a fourth of a diameter taller. The intercolumniations of columns are called pycnostyle, systyle, eustyle, diastyle, and arteostyle, and are strictly adhered to in Italian archi tecture when columns are insulated, which is not very often ; when they are attached, the interspaces are not limited, except when a peculiar arrangement called arseostyle is adopted. This consists of two systyle intercolumniations, the column that should stand in the mid-distance between two others being placed within half a diameter of one of them, making, in fact, coupled columns or pilasters. It is applied to insulated columns as well as to those which are attached. Following Vitruvius, the Italian school makes the central intercolumniation of a portico wider than any of the others. The height of arched openings, in arcades or elsewhere, is generally about twice their width ; if, however, they are arranged with a columnar ordinance, having columns against the piers, they are made to partake of the order to which the columns belong, being lower in proportion to their width with the Tuscan than with the Doric, and so on; and the piers are allowed to vary in the same manner, from two-fifths to one-half of the opening. "With columnar arrangements, moulded imposts and archi- volts are used ; the former being made rather more than a semi-diameter of the engaged columns in height, and the latter exactly that proportion. Variously moulded key stones are used, too, projecting so that they give an appear ance of support to the superimposed entablature. Smaller columns with their entablature are sometimes made to do the duty of imposts, and sometimes single columns are simi larly applied; at other times, columns in couples are allowed to stand for piers to carry arches. In plain arcades the masonry is generally rusticated, without any other projection than a plain blocking course for an impost, and a blocking course or cornice crowning the ordinance. Niches and other recesses are at times introduced in the plain piers, which are in that case considerably wider than usual, or in the spandrels over wide piers. Very considerable variety is allowed in these combinations. Doors and windows, whether arched or square, follow nearly the same propor tions, being made, in rustic stories, generally rather less than twice their width in height, and in others cither exactly of that proportion, or an eighth or a tenth more. If they have columned or pilastered frontispieces, these are sometimes pedimented ; and, except in rustic stories, whether with or without columns, a plain or moulded lining called an architrave is applied to the head and sides of a door or window. This architrave is made from one- sixth to one-eighth the width of the opening it bounds, and it rests on a blocking course or other sill, ao the case may be. In the absence of columns or pilasters in the frontispiece, their place is frequently supplied by consols or trusses of various form and arrangement, backed out by a narrow pilaster, whi( j. may be considered as the return of the frieze of the entablature, and which supports the cornice. It is not uncommon for the architrave lining to project knees at the upper angles, and this is sometimes done even with consols and their pilasters. With columned frontis pieces to gateways, doors, and windows, arose the custom, so frequent in Italian architecture, of rusticating columns, by making them alternately square and cylindrical, accord ing to the heights of the courses of rustic masonry to which they are generally attached, and with which they are less offensive than in other collocations. The practice of the Cinquecento school of piling columns on columns with their accessories is warranted by the doctrine of its master ; but his precepts not being practicable, recourse has been had to the inferior works of the Romans, which present examples of it. The difficulty of preserving anything like a rational arrangement is acknowledged on all hands to be great, if not insurmountable ; for if the first or lowest order be at an intercolumniation fitting its pro portions, the second or next above it, though diminished ever so little, is already deranged, for it has the same distance from column to column that the inferior order has whilst the columns themselves are smaller in diameter, and their entablature consequently shallower. This de rangement must, of course, increase with every succeeding ordinance, rendering it indeed impossible to make such a composition consistent. The most approved practice in arranging order above order appears to be, that the upper column shall take for its diameter the superior diameter of the one below it ; that when the columns are detached their axes shall be in the same perpendicular line ; but when attached or engaged, the plinth of the pedestal of the upper shall impend the top of the shaft of the lower column. The most rational mode, however, for diminishing, if reason can be applied to such compositions, is to carry the diminution through, the outlines of the columns of the lowest order being drawn up in the same direction, and so

the columns of every story would take up their place and