Note, finally, this contraction of the abacus. Compare 4 _c_, which is the earliest form in the plate, from Murano, with 4 _e_, which is the latest. The other profiles show the gradual process of change; only observe, in 3_a_ the abacus is not drawn; it is so bold that it would not come into the plate without reducing the bell curve to too small a scale. So much for the evidence derivable from the capitals; we have next to examine that of the archivolts or arch mouldings. [Illustration: Plate VIII. BYZANTINE ARCHIVOLTS.] _IV. Archivolts._ In Plate VIII., opposite, are arranged in one view all the conditions of Byzantine archivolt employed in Venice, on a large scale. It will be seen in an instant that there can be no mistaking the manner of their masonry. The soffit of the arch is the horizontal line at the bottom of all these profiles, and each of them (except 13, 14) is composed of two slabs of marble, one for the soffit, another for the face of the arch; the one on the soffit is worked on the edge into a roll (fig. 10) or dentil (fig. 9), and the one on the face is bordered on the other side by another piece let edgeways into the wall, and also worked into a roll or dentil: in the richer archivolts a cornice is added to this roll, as in figs. 1 and 4, or takes its place, as in figs. 1, 3, 5, and 6; and in such richer examples the facestone, and often the soffit, are sculptured, the sculpture being cut into their surfaces, as indicated in fig. 11. The concavities cut in the facestones of 1, 2, 4, 5, 6 are all indicative of sculpture in effect like that of Fig. XXVI. Vol. II., of which archivolt fig. 5, here, is the actual profile. The following are the references to the whole: 1. Rio-Foscari House. 2. Terraced House, entrance door. 3. Small Porticos of St. Mark's, external arches. 4. Arch on the canal at Ponte St. Toma. 5. Arch of Corte del Remer. 6. Great outermost archivolt of central door, St. Mark's. PLATE VIII. 7. Inner archivolt of southern porch, St. Mark's Façade. Vol. III. 8. Inner archivolt of central entrance, St. Mark's. 9. Fondaco de' Turchi, main arcade. 10. Byzantine restored house on Grand Canal, lower arcade. 11. Terraced House, upper arcade. 12. Inner archivolt of northern porch of façade, St. Mark's. 13 and 14. Transitional forms. [Illustration: Plate IX. GOTHIC ARCHIVOLTS.]