o de' Turchi, for instance, the midmost capital
of the upper arcade is the key to the whole group, larger and more
studied than all the rest; and the lateral ones are so disposed as to
answer each other on the opposite sides, thus, A being put for the
central one,

F E B C +A+ C B E F,

a sudden break of the system being admitted in one unique capital at the
extremity of the series.

Sec. VIII. Now, long after the Byzantine arcades had been contracted into
windows, this system of centralization was more or less maintained; and
in all the early groups of windows of five lights the midmost capital is
different from the two on each side of it, which always correspond. So
strictly is this the case, that whenever the capitals of any group of
windows are not centralized in this manner, but are either entirely like
each other, or all different, so as to show no correspondence, it is a
certain proof, even if no other should exist, of the comparative
lateness of the building.

In every group of windows in Venice which I was able to examine, and
which were centralized in this manner, I found evidence in their
mouldings of their being _anterior_ to the Ducal Palace. That palace did
away with the subtle proportion and centralization of the Byzantine. Its
arches are of equal width, and its capitals are all different and
ungrouped; some, indeed, are larger than the rest, but this is not for
the sake of proportion, only for particular service when more weight is
to be borne. But, among other evidences of the early date of the sea
facade of that building, is one subtle and delicate concession to the
system of centralization which is finally closed. The capitals of the
upper arcade are, as I said, all different, and show no arranged
correspondence with each other; but _the central one is of pure Parian
marble_, while all the others are of Istrian stone.

The bold decoration of the central window and balcony above, in the
Ducal Palace, is only a peculiar expression of the principality of the
central window, which was characteristic of the Gothic period not less
than of the Byzantine. In the private palaces the central windows become
of importance by their number of lights; in the Ducal Palace such an
arrangement was, for various reasons, inconvenient, and the central
window, which, so far from being more important than the others, is
every way inferior in design to the two at the eastern extremity of the
facade, was nevertheless