III. MURANO 57
corresponding to the keystone in a common arch, is, however, most fortunately left, with two lateral ones on the right hand, and one on the left.
§ 28. The keystone, if it may be so called, is of white marble, the lateral voussoirs of purple; and these are the only coloured stones in the whole building which are sculptured; but they are sculptured in a way which more satisfactorily proves that the principle above stated was understood by the builders, than if they had been left blank. The object, observe, was to make the archivolt as rich as possible; eight of the white sculptured marbles were used upon it in juxtaposition. Had the purple marbles been left altogether plain, they would have been out of harmony with the elaboration of the rest. It became necessary to touch them with sculpture as a mere sign of carefulness and finish, but at the same time destroying their coloured surface as little as possible. The ornament is merely outlined upon them with a fine incision, as if it had been etched out on their surface preparatory to being carved. In two of them it is composed merely of three concentric lines, parallel with the sides of the triangle; in the third, it is a wreath of beautiful design, which I have drawn of larger size in fig. 2, Plate 4, that the reader may see how completely the surface is left undestroyed by the delicate incisions of the chisel, and may compare the method of working with that employed on the white stones, two of which are given in that plate, figs. 4 and 5. The keystone, of which we have not yet spoken, is the only white stone worked with the light incision; its design not being capable of the kind of workmanship given to the floral ornaments, and requiring either to be carved in complete relief, or left as we see it.1 It is given at fig. 1 of Plate 4. The sun and moon on each side of the cross
1 [In one draft of this chapter Ruskin adds:-
“I hardly know whether to admire in it most the exquisite adaptation of the lines of the ornament to its form and place (their peculiar simplicity and severity indicating that this stone has a more important function than any of the others), or the sweet feeling which places the cross, between the sun and moon, at the head of the archivolt.”]
[Version 0.04: March 2008]