as in the Duomo of Florence: in
this position it is always kept smooth in surface, and inlaid (or
painted) with delicate arabesques; while the tracery and the tabernacle
work are richly sculptured. The example of its treatment by colored
voussoirs, given in Plate XIX., may be useful to the reader as a kind of
central expression of the aperture decoration of the pure Italian
Gothic;--aperture decoration proper; applying no shaft work to the
jambs, but leaving the bevelled opening unenriched; using on the outer
archivolt the voussoirs and concentric architrave in reconcilement (the
latter having, however, some connection with the Norman zigzag); and
beneath them, the pure Italian two-pieced and mid-cusped arch, with rich
cusp decoration. It is a Veronese arch, probably of the thirteenth
century, and finished with extreme care; the red portions are all in
brick, delicately cast: and the most remarkable feature of the whole is
the small piece of brick inlaid on the angle of each stone voussoir,
with a most just feeling, which every artist will at once understand,
that the color ought not to be let go all at once.

Sec. XVII. We have traced the various conditions of treatment in the
archivolt alone; but, except in what has been said of the peculiar
expression of the voussoirs, we might throughout have spoken in the same
terms of the jamb. Even a parallel to the expression of the voussoir may
be found in the Lombardic and Norman divisions of the shafts, by zigzags
and other transverse ornamentation, which in the end are all swept away
by the canaliculated mouldings. Then, in the recesses of these and of
the archivolts alike, the niche and statue decoration develops itself;
and the vaulted and cavernous apertures are covered with incrustations
of fretwork, and with every various application of foliage to their
fantastic mouldings.

Sec. XVIII. I have kept the inquiry into the proper ornament of the
archivolt wholly free from all confusion with the questions of beauty in
tracery; for, in fact, all tracery is a mere multiplication and
entanglement of small archivolts, and its cusp ornament is a minor
condition of that proper to the spandril. It does not reach its
completely defined form until the jamb and archivolt have been divided
into longitudinal mouldings; and then the tracery is formed by the
innermost group of the shafts or fillets, bent into whatever forms or
foliations the designer may choose; but this with a delicacy