The I-Zoman entablature differs also in some respects from the Grecian, and especially in the proportions of the cornice, which in the latter case is less than either of the other mem bers, averaging at about of the entire entablature, whereas in examples of Roman practice, the cornice is by far the most important division of any, the proportions of the theatre of Alarcellus giving 43 minutes to the architrave, 36 to the frieze, and 66 to the cornice, while those of the temple of Fortuna Virilis stand thus : architrave 35 minutes ; frieze 29; cornice 70; which gives a great preponderance to the cor nice. The projection of the cornice usually equals its height, or nearly so. The upper thcia of the architrave is surmounted with a fillet and ogee often enriched, and the lower not un frequently with a small echinus, also enriched, with a narrow fillet underneath. The frieze is mostly plain, and of little importance, but that of the temple of Fortuna Virilis has an attempt at decoration. The cornice is supported by an ogee moulding, and dentil-band surmounted by a fillet, a bead moulding, and a large enriched echinus; the cornice itself consisting of a corolla with a small ogee and fillet, on which is placed a cymatium. In the dentil-band, the details are often of large size, and placed rather wide apart. The Italians have not (infrequently introduced into this order what is termed a pulvinated frieze, so called from its supposed resemblance to a cushion, its profile being convex; one of the earliest examples of the pulvinitted frieze occurs in the baths of Diocletian.
The general proportions of the order, as adopted by the Grecian and Roman architects, are much alike ; the principal differences existing, as we have shown, in matters of detail. Chambers gives the height of the column eighteen modules, and that of the entablature four and a half, or one-quarter the height of the column. The base is attic, and the shaft either plain or fluted, and in the latter case with twenty, or more frequently twenty-four, flutings with fillets between, which should not be broader than one-third of the width of the flutes, nor narrower than one-quarter. The ornaments of the echinus of the capital should correspond with the flutes, so as to have an egg or dart over the centre of each flute.
Modern examples of this order in London, are— St. Pancras Church, copied from the Erectheion, and aff)rding also a specimen of Caryatides with entablature, after the small building called the Pandrosium.
The East India House, after the Asiatic examples.
The portico of Ilanover Chapel, Regent-street, after the order of Minerva Polias at Priene, which exhibits the pecu liar Ionic base.
The examples which we have selected for illustration, are as follows Plate I.—Finished drawing of the order from the temple of Minerva Potins at Athens.
Ptak same in outline.
Plate III.-1)rawing in oetline of column and entablature from the temple of Fortuna Virilis at Rolf.
l'Inte IV .—Drawing in outline of column and entablature from the temple of Alareellus at Rome.
IRON, (from the Saxon iren,) a metal of a bluish-white colour; of !treat hardne.5 and elasticity; very malleable; and exceedingly tenaehms and ductile. The ha.•dness of iron
in some states is superior to that of any othe• metal; and it has the additional advantage a suffering this hardness to he increased 11/' 1 limini,hed at pleasure, by certain ehetnival pro cesses, without altering its fm. It is, nevertheless, easily formed into any shape, and susceptible of a high degree of polish; it is the most elastic of all the metals, and, next to platina, the most diffieult or tirslun. Its tenacity is also greater than that of any other metal. except g‘dd—an iron wire, the tenth part of an inch in diameter, having been found capable of sustaining more than 500ib5. weight without breaking. Its ductility is such as to allow it to he drawn into wire as line as a hair. It is the most abundant, the most important, and the most valuable el' all tit: metal-4. Although a simple undecempounded substanee, it is not naturally fitund in this state, except in comparatively minute quatuities, but is the product of art. Some specimens el native iron, nearly pure, have been fianul in Siberia mid South America; also many iron stones, rich in the metal, supposed to be of volcanic or meteoric origin, have been fennd in numerous parts of the earth ; but all the iron a is obtained by chemical means, Iron is so universally diffused as to furin a consti tuent part • if. almost all animal, vegetabl•, and mineral sub stances. Unlike metals of hiferior utility, its ores are not distributed in thin veins, or seattered in minute particles, but are thickly stratified over many thousand: of square miles, chiefly in ttorthern regiuns of the earth, where nature has been less profuse of her other benefit:. The use of this metal is of very great antiquity, though, on amount of the difficulty of separating it frorn its ores, and of working it, probably not so remote as the employment of gold, copper, and other cemparatively soft metals, which are in many places found in a pure metallic state. It is stated by some writers, that iron is mentioned by Moses as the material of which knives and swords were fabricated ; and that Ilerodotus mentions the presentation of a saucer or vase of iron, very curiously inlaid, by AI\ attes, king of Lydia, to the Delphic oracle. Later and more erudite writers have, how eve•, maintained, that t he words of those ancient authors have been innst ineorrectly translated into cur language; and that the working and use of i•en was unknown at those periods. At what time the manufaeture of iron was first attempted in Britain cannot be precisely ascertained. Some suppose (fo• it is in reality only a probable eonjecture) that the Phanii eians, who wrought the tinonines of Cornwall, intrudneed into the country men who were skilled in metallic ore:, and capable of estimating their value, by applying the minerals to smelt purposes as their own necessities or the wants of the inhabitants might require. There is, hoe ever, much evidence to fitv4alr the belief that iron was worked in this country during the time it was in occupation by the Romans; that during the establishment of the Danes in England, the arts of mining and manufacturing the ores of iron were much improved.