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a building as a basement. In the buildings of the Greeks pedestals never obtained : the columns of their temples generally stood on the uppermost of three steps; indeed there is no existing example with any other number than three, except the temple of Theseus at Athens, which had only two, and was supposed to have been erected to an inferior deity : whatever innovations took place, were after Greece lost its independence. The Romans in many of their temples and other edifices, raised the floors so very high, that they were under the necessity of discontinuing the front stairs, which otherwise would have been found inconvenient, in occupying too much ground around the edifice; and of adopting a per destal, or podium, as a basement ; which was raised as high as the stair, and projected to the front of the steps which profiled on the sides of the pedestal. It is remarkable that Vitruvius, in treating of the Doric, Corinthian, and Tuscan orders, never mentions a pedestal; and in treating of the Ionic, he only speaks of it as a necessary part of the construction, and not as part of the order: several modern writers are also of this opinion. It must be confessed, wherever pedestals are introduced, the grandeur of the order is diminished, as all the parts are proportionably less; however there are some situations in which they are indispensably necessary, as in the interior of churches, where, if they were omitted, the beauty of the columns would be entirely lost, as so great a portion of them would be concealed by the pews. The proportions of pedestals in the ancient Roman buildings are very variable; modern authors however, have thought proper to bring them to a standard ratio, which Vignola makes one third of the height of the column; but as this proporotion oppeared to make them too high, Sir William Chambers reduced it to threetenths; these ratios, however, might vary as particular circumstances might require. The parts of pedestals may be thus proportioned: divide the height into nine equal parts, give one to the cornice, two to the base, and six to the die. The plan of the die is the same as that of the plinth of the column: the projection of the cornice may be equal to its height: the base may be divided into three parts, giving two to the plinth, and one to the mouldings; which in most cases may project equal to their height. These proportions are cominon to all pedestals. It is sometimes customary to

adorn the dies of pedestals with sunk pannels, surrounded with mouldings: the pannels are frequently charged with bas reliefs or inscriptions. Projecting tablets should never be admitted, as they are not only clumsy, but confuse the contour. The dies of the pedestals of the arches of Septimius Severus and Constantine have straightheaded niches with statues. Pedestals should never be insulated, though the columns which stand upon them were insulated. In the theatres and amphitheatres of the ancients pedestals were used in all the superior orders, while the inferior order stood upon steps. They were employed for the purpose of forming a parapet for the spectators to lean over, and for raising the base of the superior order so high, as to be seen upon a near approach to the building. In these situations the pedestals were made no higher than to prevent accidents. When pedestals are continued with breaks under the columns, or pilasters in ancient buildings; the breaks were called stylobatae; and the recess between every two stylobatae, the podium, which had the same parts disposed at the same levels as the stylobatae. Arcades. An arcade is an aperture in a wall with an arched head; which term is also sometimes applied in the plural number to a range of apertures with arched heads. When an aperture is so large that it cannot be lintelled, it then becomes necessary to arch it over. Arcades are not so magnificent as colonades, but they are stronger, more solid, and less expensive. In arcades the utmost care should be taken of the piers, that they be sufficiently strong to resist the pressure of the arches, particularly those at the extremes. The Romans employed them in their triumphal arches, and many other buildings. Arcades may be used with propriety in the gates of cities, of palaces, of gardens, and of parks; they are much employed in the piazzas, or squares

of Italian cities; and in general are of great

use, in affording both shade and shelter in hot and rainy climates; but, on the contrary, they are a great nuisance to the inhabitants, as they darken their apartments, and serve to harbour idle and noisy vagabonds. Lofty arcades may be employed with great propriety in the courts of palaces, and noblemen's houses. There are various ways of decorating the piers of arcades, as with rustics, columns, pilasters, caryatides, persians, or terms surmounted with appropriate entablatures; and some

times the piers are even so broad, as to admit of niches. The arch is either surrounded with rustic work, or with an archivolt; sometimes interrupted at the summit with a key-stone in the form of a console, or marsh, or some other appropriate sculptured ornament. The archivolt rises sometimes from a plat-band, or in post, placed on the top of the piers; and at other times from an entablature, supported by columns on each side of the arch. In some instances, the arches of arcades are supported entirely by single or coupled columns, without the entablature; as in the temple of Faunus at Rome. This form is far from being agreeable to the eye; it wants stability, as the columns would be incapable of resisting the lateral pressure of the arches, were they not placed within another walled inclosure, or in a circular colonade. In large arches the key-stones should never be omitted, and should be carried to the soffit of the architrave, where they will be useful in supporting the middle of the entablature, which otherwise would have too great a bearing. When columns are detached, as in the triumphal arches of Septimius Severus, and Constantine, at Rome, it becomes necessary to break the entablature, making its projection over the intercolumns, the same as if pilasters had been used instead of columns; or so much as is just sufficient to relieve it from the naked of the wall. This is necessary in all intercolumns of great width, but should be practised as little as possible, as it destroys the genuine use of the entablature. When columns are without pedestals, they should stand upon a plinth, in order to keep the bases dry and clean, and prevent them from being broken. Arcades should never be much more, nor much less, than double their breadth. The breadth of the pier should seldom exceed two-thirds, nor be less than one-third of that of the arcade; and the angular pier should have an addition of a third, or a half, as the nature of the design may require. The impost should not be more than one-seventh, nor less than a ninth, of the breadth of the arch; and the archivolt not more than one-eighth, nor less than onetenth, of that breadth. The breadth of the bottom of the key-stone should be equal to that of the archivolt; and its length not less than one and a half of its bottom breadth, nor more than double. In groined porticos, the thickness of the piers depends

on the width of the portico, and the superincumbent building; but with respect to the beauty of the building, it should not be less than one quarter, nor more than onethird, of the breadth of the arcade. When the arcades form blank recesses, the backs of which are pierced with doors or windows, or recessed with niches, the recesses should be at least so deep, as to keep the most prominent parts of the dressings entirely within their surface. In the upper stories of the theatres and amphitheatres of the Romans, the arcades stood upon the podia, or inter-pedestals, of the columns; perhaps as much for the purpose of proportioning the apertures, as to form a proper parapet for leaning over. Colonades. A colonade is a range of attached or insulated columns, supporting an entablature. The interval between the columns, measured by the inferior diameter of the column, is called the intercolumniation; and the whole area between every two columns is called an intercolumn. When the intercolumniation is one diameter and a half, it is called pycnostyle, or columns thick set; when two diameters, systyle; when two and a quarter, custyle; when three, diastyle; and when four, araeostyle, or columns thin set. A colonade is also named according to the number of columns which support the entablature, or fastigium: when there are four columns, it is called tetrastyle; when six, hexastyle; when eight, octostyle; and when ten, decastyle. The intercolumniations of the loric order are regulated by the number of triglyphs, placing one over every intermediate column; when there is one triglyph over the interval, it is called monotriglyph; when there are two, it is called ditriglyph; and so on, according to the progressive order of the Greek numerals. The intercolumniation of the Grecian Doric is almost constantly the monotriglyph : from this practice there are only two deviations to be met with at Athens, the one in the Doric Portico, and the other in the Propylaea; but these intervals only belong to the middle intercolumniations, which are both ditriglyph, and became necessary, on account of their being opposite to the principal entrances. As the character of the Grecian Doric is more massy and dignified than that of the Roman, the monotriglyphic succeeds best; but in the Roman it is not so convenient, for the passage through the intercolumns would be too narrow, particularly in small buildings; the ditriglyph is therefore more generally adopted. The araeostyle is only applied to rustic structures of Tuscan intercolumniations, where the columns are lintelled with wooden architraves. When the solid part of the masonry of a range of arcades are decorated with the orders, the intercolumns become necessarily wide; and the intercolumniation is regulated by the breadth of the arcades, and that of the piers. It does not appear that coupled, grouped, or clustered columns, ever obtained in the works of the ancients; though, on many occasions they would have been much more useful: we indeed find, in the temple of Bacchus at Rome, columns standing as it were in pairs; but as each pair is only placed in the thickness of the wall, and not in the front, they may rather be said to be two rows of columns, one almost immediately behind the other. In the baths of Dioclesian, and in the temple of Peace at Rome, we find groined ceilings, sustained by single Corinthian columns; a support both meagre and inadequate. Vignola uses

the same intercolumniation in all his orders:

this practice, though condemned by some, is founded upon a good principle; it preserves a constant ratio between the columns and the intervals. Of all the kinds of intercolumniation, the custyle was in the most general request among the ancients; and though in modern architecture both the custyle and diastyle are employed, yet the former of these is still preferred in most cases: as to the pycnostyle interval, it is frequently rejected for want of room, and the araeostyle, for want of giving sufficient support to the entablature. The moderns seldom employ more than one row of columns, either in external or internal colonades; for the back range destroys the perspective regularity of the front range: the visual rays, coming from both ranges, produce nothing but confusion in the eye of the spectator. This confusion, in a certain degree, also attends pilasters placed behind a row of insulated columns: but in this the relief is stronger, owing to the rotundity of the column, and the flat surfaces of the pilasters. When buildings are executed on a small scale, as is frequently the case of temples, and of other inventions used for the ornaments of gardens, it will be found necessary to make the intercolumniations, or at least the central one, broader than usual, in proportion

to the diameter of the columns; for, when the columns are placed nearer each other than three feet, the space becomes too narrow to admit persons of a corpulent habit. Pilasters and Antae. Pilasters are rectangular prismatic projections, advancing from the naked part of a wall, with bases and capitals like columns, and with an en tablature supported by the columns; hence they differ from columns, in their horizontal sections being rectangles, whereas those of columns are circles, or the segments of circles, equal to or greater than semicircles. It is probable that pilasters are of a Roman invention, since there are but few instances in Grecian buildings where they are repeated at equal or regular intervals, and these only in the latter ages of Greece, as in the monument of Philopapus; (unless in that of Thrasyllus) but of their application in Roman works there are numberless instances: Vitruvius calls them parastatae. The Greeks used a kind of square pillars only upon the ends of their walls, which they called antae, which antae projected sometimes to a considerable distance from the wall of the principal front, and formed the pronaos or vestibulum. The breadth of the antae on the flanks of the temples was always considerably less than on the front: these antae had sometimes columns between them, and when this was the case, the return within the pronaos was of equal breadth to the front. The capitals of the antae never, correspond with those of columns, though there are always some characteristic marks, by which the order may be distinguished. Pilasters, or parastatae, when ranged with columns under the same entablature, or placed behind a row of columns, have their bases and capitals like those of the columns, with the corresponding parts at the same heights, and when placed upon the angles of buildings, the breadth of the returns is the same as that of the front. The trunks of pilasters have frequently the same diminution as the shafts of the columns, such as in the arches of Septimius Severus, and Constantine, and in the frontispiece of Nero, and the temple of Mars the Avenger, at Rome; in this case, the top of the trunks of the pilasters is equal to the breadth of the soffit of the architrave, and the upright face of the architrave resting on the capital, in the same perpendicular as the top of the pilaster. When the pilasters are undiminished, and of the same breadth as the co

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