under them, and
thereby applied at far better advantage. And, in the second place, the
joints of the masonry were changed. In the Frari (as often also in St.
John and St. Paul's) the tracery is formed of two simple cross bars or
slabs of stone, pierced into the requisite forms, and separated by a
horizontal joint, just on a level with the lowest cusp of the
quatrefoils, as seen in Fig. XXI., _a_. But at the Ducal Palace the
horizontal joint is in the centre of the quatrefoils, and two others are
introduced beneath it at right angles to the run of the mouldings, as
seen in Fig. XXI., _b_.[76] The Ducal Palace builder was sternly
resolute in carrying out this rule of masonry. In the traceries of the
large upper windows, where the cusps are cut through as in the
quatrefoil Fig. XXII., the lower cusp is left partly solid, as at _a_,
merely that the joint _a b_ may have its right place and direction.

[Illustration: Fig. XXII.]

Sec. IV. The ascertaining the formation of the Ducal Palace traceries
from those of the Frari, and its priority to all other buildings which
resemble it in Venice, rewarded me for a great deal of uninteresting
labor in the examination of mouldings and other minor features of the
Gothic palaces, in which alone the internal evidence of their date was
to be discovered, there being no historical records whatever respecting
them. But the accumulation of details on which the complete proof of the
fact depends, could not either be brought within the compass of this
volume, or be made in anywise interesting to the general reader. I shall
therefore, without involving myself in any discussion, give a brief
account of the developement of Gothic design in Venice, as I believe it
to have taken place. I shall possibly be able at some future period so
to compress the evidence on which my conviction rests, as to render it
intelligible to the public, while, in the meantime, some of the more
essential points of it are thrown together in the Appendix, and in the
history of the Ducal Palace given in the next chapter.

Sec. V. According, then, to the statement just made, the Gothic
architecture of Venice is divided into two great periods: one, in which,
while various irregular Gothic tendencies are exhibited, no consistent
type of domestic building was developed; the other, in which a formed
and consistent school of domestic architecture resulted from the direct
imitation of the great design of the Ducal Palace. We mus