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PLATE VII.

We have observed before, that every Doric structure must be regulated by the triglyphs andmetopes. The proper distribution for a Doric colonade would be only that of two triglyphs, asdesigned for the middle of the portal in the last plate; but the necessity of a wider intercolum-niation, may, on some occasions, require three triglyphs; in this cafe the columns may be dis-posed by couplets, for a sufficient strength to support the entablature at fig. A.

Near Trevi, between Fuligno and Spoleto, is a little temple, where the portals are supportedat the angles by columns and pilasters in couplets. But this is a corruption of the antique pu-rity, which considered equi-distant columns, with narrow intercolumniations, as producingthe most desireable effects, both on account of strength and beauty.

The boasted colonade of the Louvre by Perrault would have merited much higher commendation,if the intercolumniations between the center and the ends, had been equidistant, instead of cou-plets ; thereby the jambs of the niches might have been somewhat obscured, but the very elegantdisposition of the columns, would have sufficiently made amends : it is more essential to avoiderrors in the greater lines of a design, than to be over scrupulous about the minutiæ of little parts.

The Grecians called a colonade or pbrtico, Stoa, which gave the name of Stoics to the dis-ciples of Zeno, who were accustomed to assemble together in the porticos. When a porticosurrounds internally any open oblong or square space, it is called a peristyle, to distinguish itfrom the periptere, where the columns are disposed without-side.

The Doric Arcade B. is designed without columns; for this purpose, the height of the archis to its breadth as seven to four ; (and it loses its proportional character; if made higher.) Di-vide the given height a. b. into eleven equal parts, take two for the height of the entablature*which by the proper modulation is divided into the requisite members. Let the extent of fourtriglyphs and three metopes six the breadth of the aperture, then the breadth of the pier willConsist of two metopes and one triglyph* The rest may be collected by inspection of thefigure.

If with the above breadth for the aperture of the arch, yod make its height only once and ahalf its breadth, it would then admit of femicolumns against the piers, raised upon plinths, asfig. E. but the expences of columns against the piers of arcades seem very useless for commonpurposes. For theatres and amphitheatres, the addition of the femicolumns to the piers, gave anadditional strength, by increasing the depths of the piers, and served to break the too greatplainness or nakedness which otherwise would have appeared upon such vast extents. Pilastersprojecting from the piers of arcades, from one eighth to one fourth of their diameters, havesometimes taken place instead of femicolumns. The archivolt C. and the impost D. shouldhave their members and mouldings characteristically described from the architraves in every order.

Key-stones, whether plain or scrolled, with ornaments of masks or foliage, interrupting themembers of the archivolt, give it an apparent weakness, and destroy the beautiful effect andsimplicity of the semicircular sweep : perhaps it may not be judged so by others, who will bringagainst this opinion the authority of key-stones from some of the Roman antiquities, and fromthe practice of several of the best moderns ; but if an ornament is ill-placed, no authority shouldprotect it.

CHAP.