In the temple of Erectheus, the column terminates with a fillet and astragal a little below the eye of the vo lute ; and in the temple of Minerva Polias, it is termi nated with a single fillet. In both instances, the colcrino or neck is decorated with honey suckles. The upper annular moulding of the column is of a semi-circular section with a guilloche.
The capitals of both Greek and Roman Ionics have the eschinus, astragal, and fillet; the eschinus is always cut into eggs, surrounded with borders of angular sec tions with tongues between them; the astragal consists of a row of beads, having two small ones inserted be tween every two large ones. In all the Roman build ings, except the Coliseum, these mouldings are cut in the same manner.
When Ionic columns stand in the flanks as well as the fronts of a building, two volutes at the corner of each angular column is contrived to present the same form in the flank as in the front, as in the temple of Bacchus at Tcos, of Minerva at Prime, Erectlicus, and that of the Muses at Athens, and likewise of Fortuna Virilis at Rome: the angular capitals have, in all these instances, one volute on each side, projected in a curve towards the angle. Amongst the ancient Romans, as at the temple of Concord at Rome, the capitals of all the columns arc made to face the four sides of the abacus; and it was from this specimen that Scammozzi, encouraged by the example of Michael Angelo. composed the capital upon this principle, which bears his name.
The following examples will slim the number of flutes and their form in the temples of the I lyssus. Ercc diens and Minerva Poliasat Athens, Bacchus at Tcos, Minerva Polias at Prime, and Apollo at Didymxus, near column has 24 flutes, and as many fillets. The columns of the aqueduct of Adrian, the Ionic co lonnade near the Lantern of Demosthenes, and the great theatre at Laodicea, also at the temple of Concord, the second order of the Coliseum, and the theatre of Mar cellus at Rome, have their shafts plain; but the columns of the temple of Fortune, at the same place, have 24 flutes. The section of the flutes of the columns, in the temple on the Ilyssus at Athens, is elliptical; the flutes descend and follow the curse of the scape of the column in the following specimens, 1Z. the temple of Mmena
Polias, and of Erectheus at Athens, the temple of elms at Teos, and Minerva Polias at Priem.
Method of describing the Ionic Volute.
To describe the Ionic volute with any number of revo lutions or quarters to any given height, and to touch a circle of a given radius within the spiral.
Let All, Plate CLXXXIV. Fig. I. No. I. be the height of the volute. Divide AB into two equal parts at C. From AB cut off AD, equal to the radius of the eye. Divide DC into as many equal parts as the volute is to consist of quadrants, (which, in this example, are 12,) at the points I, 2, 3, ke. Draw CE, at any angle with AB, equal to two of these parts : draw I 1 f perpen dicular to CD, equal to CE : draw fg perpendicular to 1 i f, equal to I I Q: draw g h perpendicular to gf, equal to 10 P. Proceed in this manner until all the sides of the spiral fret are drawn. Produce 11 f to I, fg to 2, g h to 3, and so on. Upon the centre at I I, with the dis tance d B, describe the arc B I ; from the centre f, with the distance f 1, describe the arc = I, 2; from g, with the distance g 2, describe the arc 2, 3. Proceed in the same manner with all the remaining arcs, the last termi nating at 12. Then, from the centre r, with the radius r 12, describe a circle for the eye of the volute ; and the radius, r 12, of this circle will be equal to AD as requir ed, provided the operation be accurately performed.
After the same manner may the inner spiral be drawn. Fig. 1. No. 2. shows the construction of the centres to a larger scale, and by a method not so liable to inaccuracy, as follows : Having made df equal to CE, divide it into halves at e ; draw e r perpendicular to df, equal to e d or ef, and draw d in r, and f k o r. Make e s, s t, t r, equal each to G 2 on the scale : draw i s k, n t o parallel to df; make fg perpendicular to elf, equal to 11 Q : draw the diagonal gin parallel to dinr: draw A- 1, on, n i h, perpendicular to d f ; draw g h parallel to I If : draw the diagonal h m q : draw Int and 1t q parallel to f d, and d,f,g,h,q, c, will be the centres. This me thod is not so liable to error, as taking the parts succes sively from the scale, and applying them to the spiral fret in the same order.