check the Austrian cavalry in the battle under the walls of Verona. The
finer dust among which these pebbles are dispersed is taken up by the
rivers, fed into continual strength by the Alpine snow, so that, however
pure their waters may be when they issue from the lakes at the foot of
the great chain, they become of the color and opacity of clay before
they reach the Adriatic; the sediment which they bear is at once thrown
down as they enter the sea, forming a vast belt of low land along the
eastern coast of Italy. The powerful stream of the Po of course builds
forward the fastest; on each side of it, north and south, there is a
tract of marsh, fed by more feeble streams, and less liable to rapid
change than the delta of the central river. In one of these tracts is
built RAVENNA, and in the other VENICE.

SECTION V. What circumstances directed the peculiar arrangement of this
great belt of sediment in the earliest times, it is not here the place
to inquire. It is enough for us to know that from the mouths of the
Adige to those of the Piave there stretches, at a variable distance of
from three to five miles from the actual shore, a bank of sand, divided
into long islands by narrow channels of sea. The space between this bank
and the true shore consists of the sedimentary deposits from these and
other rivers, a great plain of calcareous mud, covered, in the
neighborhood of Venice, by the sea at high water, to the depth in most
places of a foot or a foot and a half, and nearly everywhere exposed at
low tide, but divided by an intricate network of narrow and winding
channels, from which the sea never retires. In some places, according to
the run of the currents, the land has risen into marshy islets,
consolidated, some by art, and some by time, into ground firm enough to
be built upon, or fruitful enough to be cultivated: in others, on the
contrary, it has not reached the sea-level; so that, at the average low
water, shallow lakelets glitter among its irregularly exposed fields of