PROPYLAEUM (rpor6aaior : the great entrance to the Acropolis of Athens was called wpondAam,in the plural number; Thucydides, ii. 13), algnifying literally a fore-portal or one detached from and placed in advance of the building to which it gave access, is used as a distinctive term for the structures through which was tho entrance into the enclosure surrounding some of the Grecian temples. Unlike the vast truncated pyramidal mares or moles that enclosed the forecourt of Egyptian temples, on the entrance hide, leaving only a lofty square headed portal for access, thereby screening the main edifice and colonnade, within the court, and giving the exterior the aspect of a fortress's—the propylaea of the Greeks were detached structures placed io advance of the sacred edifice itself, so as to mark very conspicuously the approach to it through the outer enclosure or boundary. They seem to have been intended in some degree to prefigure the teua0o to which they conducted ; their general appearance in front being almost Identically the same as that of the frontispiece-facade or pediment cud of a prostyle temple.
The general arrangement and diameter of a Greek propylreum ma be described as similar to those of an arnphIprostyle temple [Trill-LEI Shorter however on its sidea than the width in front, and without any dila, yet not entirely open to both fronts, but divided by en inner wall across It from side to side, Into two portions, the outer one of Which, answering to the preened of a temple, was larger than the other ; so that the whole may be more briefly, if not more intelligibly explained, by comparing the plan to the pronaes and opisthodomus of an stupid prostyle temple, put together without any intervening cella, being separated only by the wall above mentioned, In which were as many open doorways as there were intercolumne In front.
Such was the disposition of the propylaea both of the Parthenon at Athenti and of the temple at Elousis, the only two exampled of such structures known to us, and the latter now so only by the drawings of it In the unedited antiquities of Athens : there were, indeed, as we learn frdm Pattaanias (IL 3) propylaea at Corinth, Lut of their archi tectural design we know nothing. The Athenian structure stands on the west aide of the Acropolis, but is not on the same axis or line as the temple. TWA propylicum, which was begun by the architect Mtn:aide/I in the 4th year of the 85th olympiad, and completed In five 3-ears, is of the Doric order, and hexastyle on both fronts ; and the outer or western one was greatly extended by two flanking wings pro jecting forward at right angles, so as to enclose the platform to which ail ascent of steps led up from below, and above which the portico and the two lesser colonnades forming the aides of the wings were raised upon three other steps. Thus the platform (78 feet from north to
south, by 40 east and west) bccamo an elevated open fore-court, pre senting a principal portico in front crowned by a pediment, and two colonnades, which being considerably lower (their columns 19 feet, the others 28i feet high) gave greater importance to the fernier; and a degree of scenic effect—combination, contrast, and variety—was pro. dueed, very unusual in Grecian architecture.
One of the most remarkable circumstances which served to dis tinguish the Propyla from a portico is that in the outer division there Were two rows of inner columns placed not parallel with, but at right angles to the columns in front, and in a line with the two middle ones, thereby dividing the plan internally into three compartments, the centre one narrower than the other two, and forming au avenue to the principal doorway, which was the largest and loftiest of the five openings in the transverse wall, and the two end ones the smallest. These inner columns, too, instead of being of the same order a4 the exterior, were Ionic,—.a very remarkable peculiarity, inasmuch as it evidences an intermingling of styles almost unknown to Grecian architecture. The licence—so to call it—was, however, fully justified by the circumstances of the case, because columns of lesser diameter than the external ones were required, and also of such height as to reach the architrave soffits of the internal ceiling, which are in a lino with the top of the architrave of the external order.
The Eleusis propykeum resembled that of the Acropolis in nearly all particulani, except that it had no wings attached to it. Like the Athenian one, it was of the Doric order, hexastyle on both fronts, and had sit Ionic columns within, similarly in two rows.
As modern structures partaking of the ancient Greek propyketun character, may be mentioned Cagnola'a Porta Ticineuse at Milan, and the London terminus of the London and North-Western Railway, in Euston Square, which, though only a distyle in antis in both fronts, is a fine example of Grecian Doric upon a scale of extraordinary magnitude. Both the modern examples, however, differ from the ancient ones in being entirely open, without any internal transverse wall ; and the Italian one has, moreover, a large open arch on each side, forming a passage through it in that direction.