raise so ponderous
a structure upon so narrow a foundation.

The builders of the Campanile proceeded as follows: Into this bed of
compact clay they first drove piles of about 9 1/2 in. in diameter with a
view to consolidate still further, by pressure, the area selected. That
area only extends 1.25 meter, or about 4 ft. beyond the spring of the
brickwork shaft of the tower. How deep these piles reach Boni's report
does not state. The piles, at the point where he laid the foundation
bare, were found to be of white poplar, in remarkably sound condition,
retaining their color, and presenting closely twisted fiber. The clay in
which they were embedded has preserved them almost intact. The piles
extended for one row only beyond the superimposed structure. On the top
of these piles the builders laid a platform consisting of two layers of
oak beams, crosswise. The lower layer runs in the line of the Piazza,
east to west, the upper in the line of the Piazzetta, north to south.
Each beam is square and a little over 4 in. thick. This oak platform
appears to be in bad condition; the timbers are blackened and friable.
While the excavation was in progress sea-water burst through the
interstices, which had to be plugged.

Upon this platform was laid the foundation proper. This consisted of
seven courses of stone of various sizes and of various kinds--sandstone
of two qualities, limestone from Istria and Verona, probably taken from
older buildings on the mainland, certainly not fresh-hewn from the
quarry. The seventh or lowest course was the deepest, and was the only
one which escaped, and that but slightly; the remaining six courses were
intended to be perpendicular. These courses varied widely from each
other in thickness--from 0.31 to 0.90 meters. They were composed of
different and ill-assorted stone, and were held together in places by
shallow-biting clamps of iron, and by a mortar of white Istrian lime,
which, not being hydraulic, and having little affinity for sand, had
become disintegrated. Boni calls attention to the careless structure of
this foundation proper, and maintains that it was designed to carry a
tower of about two-thirds of the actual height imposed upon it, but not
more.

Above the foundation proper came the base. This consisted of five
courses of stone set in stepwise. These courses of the base were all the
same kind of stone, in fairly regular blocks, and of fairly uniform
thickness. They were all intended t