From The Four books of Architecture, By Andrea Palladio
C H A P. XVI.
Of the IONIC ORDER.
The Ionic order had its origin from Ionia, a province in Asia, of which it is said that the temple of DIANA at Ephesus was built. The columns, with the capital and base, are nine modules high. By a module is understood the lower diameter of the column.
The architrave, frieze, and cornice are a fifth part of the altitude of the column. In the designs of simple colonnades, the intercolumniations are of two diameters and a quarter, which is the most beautiful and commodious manner of intercolumniations, and by VITRUVIUS called eustilo’s. In the design of arches the pilasters are a third part of the void, and the arches are two squares high.
If a pedestal is to be put to Ionic columns ~ as in the design of arches, it must be made as high as half the width of the arch, and divided into seven parts and a half; two of which are for the base, one for the cimacia, and the remaining four and a half for the dado, that is, the middle plain.
The base of the Ionic order must be half a module in thickness, and divided into three parts; one to be given to the plinth, whose projecture is the fourth and eighth part of the module; the other two are divided into seven parts, three of which are for the bastone or torus; the other four are again divided into two, of one is made the upper cavetto, and with the other the lower, which must project more than the other.
The astragal must be the eighth part of the cavetto. The cimbia of the column is the third part of the bastone or torus of the base. But if the base is joined with part of the column, then the cimbia must be made thinner, as I have said in the Doric order. These are the dimensions of the Ionic base, according to VITRUVIUS.
But as in many ancient buildings, Attic bases are seen placed under the columns of this order, and they please me better so, I have drawn the said base upon the pedestal, with a little torus under the cimbia; but at the same time I have not omitted the design of that ordered by VITRUVIUS.
The designs marked L are two different profiles, to make the imposts of arches, the dimensions of each of which are marked in numbers, showing the minutes of the module, as it has been observed in all the other designs. These imposts are half as high again as the pilaster is thick, which supports the arch.
A, Shaft of the column.
B, Tondino or Astlragal, with the Cimbia, and are members of the column.
C. upper Bastone or Torus.
E, lower Baslone or Torus.
F, Orlo joined to the Cimacia of the pedestal.
G, the Cimacia in two different forms (of the pedestal)
H, Dado (of the pedestal)
1, Base in two different forms (of the pedestal)
K, Orlo or Plinth of the Base.
L, Imposts of the arches.
To form the capital, the foot of the column must be divided into eighteen parts, and nineteen of these parts is the height and width of the abaco, half thereof is the height of the capital with the volute, which is therefore nine parts and a half high; one part and half must be given to the abaco with its cimacio, the other eight remain for the volute, which is thus made.
One of the nineteen parts is to be allowed from the extremity to the inside of the cimacio, and from that place where the point was made, a line must fall perpendicular, which divides the voluta in the middle, called catheto. And where the point is upon the line that separates the superior four parts and a half from the inferior three and a half, the center of the eye of the voluta must be made, whose diameter is one of the eight parts. And from the said point a line must be drawn, which intersecting with the catheto at rectangles, divides the voluta into four parts.
Then a square ought to be formed in the eye of the voluta, half the diameter of the said eye in bigness, and diagonal lines drawn. Upon which lines the points are marked whereon the fixed foot of the compasses must be placed in forming the voluta. These are thirteen in number, including the center of the eye of the said voluta. The order that ought to be observed in them will plainly appear by the numbers placed in the design.
The astragal of the column is in a direct line with the eye of the voluta. The thickness of the voluta in the middle must be equal to the projecture of the ovolo, which projects beyond the abaco just as much as the eye of the voluta is. The channel of the voluta is even with the shaft of the column.
The astragal of the column goes quite round under the voluta, and is always seen, as appears by the plan: For it is natural, that a thing so tender as the voluta is supposed to be, should. give way to a hard one, such as the astragal, from which it must always be equally distant.
Capitals are generally made in the angles of colonnades and portico's of this order, with volutes not only in front, but also in that part which, if the capital were made as usual, would be the flank; by which means they have the fronts on two sides, and are called angular capitals. I shall show how these are made in my book of temples.
B, Channel or hollow of the Voluta.
D, Tondino or astragal under the Ovolo.
F, Shaft of the column.
G ,The line called Catheto.
IN the plan of the capital the said members are countermarked with the fame letters.
S., The eye of the Voluta in a larger form.
Members the base, according to VITRUVIUS.
K, Shaft of the column.
Bastone or Torus.
N, First Cavetto.
0, Tondini or Astragals.
P, Second Cavetto.
Q, Orlo or Plinth.
R, Projecture of the base.
The architrave, frieze and cornice are, as I have said, a fifth part of the height of the column, the whole to be divided into twelve parts, of which the architrave is four parts, the frieze three, and the cornice five.
The architrave is to be divided into five parts; of one its cimacio is made, and the remaining four divided into twelve parts, three of which are given to the first fascia and its astragal; four to the second and its astragal, and five to the third.
The cornice is to be divided into seven parts and three fourths; two mull be given to the cavetto and ovolo, two to the modillion, and three and three fourths to the corona and gola or cima. Its projecture is equal to its height. I have designed the front, flank, and plan of the capital ; as also the architrave, frieze, and cornice, with their proper ornaments.
A, Gola or Cima recta.
B, Gola, or Cima reversa.
C, Gocciolatoio or Corona.
D. Cimacio of the Modiglions.
N, Abaco. 0, Hollow of the Voluta. P, OV010.
H, Forego or frieze.
1, Cimacio of the arcbitrave.
K, First Fascia
L, Second Fascia.
M, Third Fascia.
MEMBERS of the capital.
O, Hollow of the Voluta,
Q, Tondino of the column or astragal.
R, Shaft of the column.
The soffit of the cornice is where the roses are between one modillion and the other.