Plate 51. Drawing the Ionic Volute, by Palladio and Vignola

Although every draughtsman should be able to readily draw the spiral line, as, for instance, the volutes of the Corinthian capital, the sides of consoles and in many kinds of ornamentation, nevertheless, when drawing the volute of the Ionic capital, he is glad to use the compass whenever it is possible to do so. For that reason we give the following methods in addition to those shown on Plates 36, 39, 40, and 41.

Plate 51 shows two, very little different, volutes, the construction of which can be accomplished by the scheme shown in the eyes, from which the methods of the oldest authors can be understood. That of Vitruvius was not for a long time understood, as the descriptive drawings on which his text was based were lost. About the middle of the sixteenth century Palladio, and at about the same time also Philibert de Lorme, discovered in a Basilica at Rome, an incompleted antique Ionic capital, on the eye of which the entire scheme laid off for the carver was preserved, wherefrom all at once the difficulties encountered by the followers of Vitruvius were cleared away. Alberti, who died 1472, still described his volute with four semicircles from points lying on the vertical axis of the eye.

Palladio endeavored to fill out a part of the curves between the 4th and 5th as also between the 8th and 9th quadrants with a horizontal connecting line, by which, however, the spiral line is broken in an unpleasing manner.

Vignola has the same scheme in the eye, and obviates the mistakes of Palladio by making the 4th and 8th quarter windings larger than quadrants, and the 5th and 9th correspondingly less. The connection with the eye requires a horizontal line, and makes an angle with the periphery of the eye. In both methods the starting and ending points of the quadrants can not be established by a simple calculation, as is possible with the method given on Plate 36, where for the drawing of the volute a great accuracy is obtained.