210

ARCHITECTURE.

of an architrave r, a frieze b, and a cornice a. l.The plinth Ilakes it.; appellation from wmvJo;, a brick or flat square stone onwhich columns in the most early state of architecture are sup-posed to have stood. 2 , The dado, or dye, is so called becau eit is of a cubic form. 3. 'Die cornice is derived from coronis, atop or summit; because the cornice is the extreme end or flush-ing of tl>e pedestal. 4. The base of the column is from /Sun;,a foundation or footing for the column. 5. The shaft, that longand straight part of a column comprehended between the baseanti capital, is so named from aw.A to dig, in tiie manner of awell, round and deep, whose inside resembles the shape of apillar. 6 . The capital, from xifiXn, or caput, the head, whichthe capital is to a column. 7. The architrave, from a-xi; chiefor principal, and trabs a beam, because the architrave is the chiefsupport to the whole entablature. 8 .The frieze, is so called fromtn~soy a border or fringe, which some of the ancients used to call£ 051000 ;; because their ft iezes were usually enriched with the figuresof animals. 9. The cornice of the entablature, or the crowningpart of the entire order, is explained above. These nine princi-pal parts of a complete order, the dado and shaft excepted, arecomposed of small members, which constitute all that simple andpleasing variety of ornament which adorned the works of theancients. There are eight regular mouldings in ornamenting co-lumns. See Plate XIII. The tdlet, listel, or square, tig. 1 .; the as-tragal or bead, fig. 2 .; the torus, or tore, fig. 3. ; this differs fromthe astragal in size only ; the scotia, mouth, or casement, tig. 4. ; theechinus, ovolo, or quarter-round, tig. 5 .; the inverted cyma, talon,or ogee, fig. 6 .; the cyma, cyma recta, orcymatium, iig.. 7. ; thecavetto, or hollow, fig. 8 . The fillet, astragal, and torus, servefor binding the parts with which they are connected. The ovolo isused to support projecting parts. The cyma recta, in versa, andcavetto are for sheltering the smaller members. There are variousmethods of describing the contours of these ; but the simplestand perhaps the be-t, is to form them of quadrants of circles, asshewn in the plate. The names of these moulding; allude totheir forms, and their forms are adapted to the purposes for whichthey were intended. A proper disposition of the mouldings formsthe various members, the names of which, with their origin, anduse follow. The figures refer to the numbers in Plate XU.fig. 1 . No. 1 . The fillet, from the French,/ ;/, a thread. ' 2 . Thecavetto, from cuvu. s, hollow. 3. The cyma rewersa, the cyma-tium inverted. 4. The corona, or crow n, because it is the prin-cipal member of the cornice, and serves as a shelter to the smallermouldings of the entablature. 5. The ovolo, from ovum anegg ; because this member by the ancients was frequently carvedin the form of an egg. (i. The capital, or upper fillet of thetriglyph. 7. The trigiyph, from the three engravings,

compounded of r;e‘, three, and to carve or engrave ; in

conformity to which, the triglyph has two entire channels and twohalf ones, with three spaces between. 8 . The metope, from[Miami, the space between one aperture or hole to another; thetriglyphs being supposed to be joists that fill the apertures : hencethe space between the triglyphs, which forms-an exact square, istermed the metope. 9 . The frieze is explained above. 10 . Theband is the same as the fillet. 11 . The guttir, or the drops, areof a conic figure. 12 . The architrave. See the explanationabove. 13. The facia, or face ; of these there are two in thearchitrave. 14. Thu cymutium, or cyma recta, from iov, awave ; because tins member resembles the swelling and concavityof a wave, 15. The abacus, from aGa£, a shelf or table, or assome suppose, a tiie, on which the ancient Creek mathematiciansstrewed dust, to draw their geometrical schemes on. The wordseems to have been introduced into architecture on the inventionof the Corinthian capital, which took its ri-e from an acanthusgrowiug round a basket. See Plate XI. tb. The ovolo of thecapital, which in this situation must be considered as the basketround which the acanthus grew. 17. The annulets ; so calledbecause these small fillets encompass the capital, like rings joinedto each other. The moderns, in place of these, generally have asmall cavetto. 18. The colorino, the collar, or neck of thecapital. 19. The astragal, from «;p«yayo;, a hone of the heel; orthe curvature of the heel, which this member resembles. Thehollow which follows is termed «so fvyi, the escape, because thispart of the column appears to fly oil'. 20 and 22 . The upperand lower torus, from too,-, a cable, which this- mouldhig some-what resembles. 21 . The scotia. from to™, darkness; because

O

of the strong shadow which its concavity produces, and whichis increased by the projecting torus above. In some of the Doric entablatures are inulules, (as 1), Plate XII. lig. 1 .) from mutuli,modillions, which are placed perpendicular over each triglyph,and are of tiie same width ; and whose projection in the corona isthe same, forming a perfect square. In others are dentils, as inthe theatre of Marcellus at Rome . These are so named fromdentes, teeth, which they resemble; and the Hat member onwhich these dentils are placed is termed denticulus. The capitalsof tiie Ionic, Corinthian , and Composite, (see Plate XIV.)have each of them volutes, so called from rolutum, to roll round,as on a staff. Some call the volutes the horns of die capital, be-cause they resemble the twisting of rams’-horns. An assemblageof what are called essential parts and mouldings is termed a profile.The most perfect profiles are such as are composed of few mould-ings, varied in form and size ; and so disposed, that the straightand curved oiu-s succeed each other alternately. When orna-ments are employed in mouldings, some of them should he leftplain, in order to give a proper repose: for when all are orna-mented, the figure of the profile is lost. To diminish the shaftsof columns the ancients adopted a variety of methods ; beginningsometimes from the foot of the shaft, and at others from one quar-ter, or one third of its height; the lower part being perfectlycylindrical. The former ot these was most in use amongst theancients, and, being the most natural and graceful, ought to havethe preference, though the latter has been more universally prac-tised by modern artists. M. Biondel, in his work intitled Reso-lution des quatre principaux Problemes d’Architecture, teachesvarious manners of diminishing columns; the best and simplestof which is by means of the instrument which Nicomedes inventedto describe the first conchoid : for this, being applied at thebottom of the shaft, perforins at one sweep both tl-.e swelling andtiie diminution ; giving such a graceful form to the column, thatit is universally allowed to be the most perfect practice hithertodiscovered. The columns in the Pantheon, accounted the mostbeautiful among the antiques, are made in this manner ; as appearsby the exact measures of one of them to be found in Desgodetz ’sAntiquities of Rome. To give an accurate idea of the operation,,it will be necessary first to describe Vignola’s method of diminu-tion, on which it is grounded. Having determined the heightof the shaft, draw a line indefinitely from D (Plate XIII. fig. 11 .)through C, perpendicular to the axis OP of the column ; take thenID, half the inferior or largest diameter of the column, andplace one foot of the compasses exactly on the extremity of thesuperior or smallest diameter, as at R, and depress the other,till it come into the axis or centre line of the shaft, as at S underO ; through these two points draw a line indefinitely and pro-duced till it cut the line DC, as at A ; from A, the centre, drawany number of lines through the axis OP, asS r, S r, Ac.; andon each of these place half the larger diameter of the shad set offfrom the axis or perpendicular line OP, through which points,thus found, if a curve line he drawn, it will describe the swellingand proper diminution of the column. Although this method hesufficiently accurate for practice, especially if a considerablenumber of points be found, yet, strictly speaking, it is defective;as the curve must either be drawn by hand, or by applying aflexible ruler to all the points; both of which are liable to vari-ations. Biondel, therefore, to obviate this objection, alter havingproved the curve passing from O to R through the points r, r, tobe of the same nature with the first conchoid of the ancients, em-ployed the instrument of Nicomedes lo describe it: tiie con-struction of which is as follows. This instrument is made ofwooden lathes in the triangular form described by PO, PC , andAPR, (Plate Xlll. tig. 11.) the base and perpendicular ofwhich are joined together at P, and has a stay: the upright OPhas a groove cut in it. To the lath ABU at S is fixed a button,which passes along the groove from P to 0 ; in the moving lathA UR is a common groove, cut through from A to B; and at A,in the lath DC, is fixed a button at the centre A, as described inthe lir-t method. The length of the groove AB must exceed theditf'erence of the length AS to AP ; consequently, as the buttonS works in the groove OP, the groove AB permits it to move for-ward to P, by which the former swelling and diminution will berao't correctly performed when a pencil is fixed at R, at a dis-tance from the button S equal to half of the largest diameter ofthe column. It is farther to be observed, that Nicomedes’s in-strument