village on either
side, and we followed down the left bank in a north-easterly direction
for several miles without seeing any considerable place. The river has
here, as through nearly its whole course, a strong, rapid current, and
was swollen and rendered turbid by recent rains. I judge that its
surface was decidedly above the level of the adjacent country, which is
protected from inundation (like the region of the Lower Mississippi) by
strong embankments or levees, at first natural doubtless--the product of
the successive overflows of centuries but subsequently strengthened and
perfected by human labor. The force of the current being strongest in
the center of the river, there is either stillness or an eddy near the
banks, so that the sediment with which the current is charged tends
constantly to deposition on or against the banks. When the river rises
so as to overflow those banks, the downward current is entirely unfelt
there and the deposition becomes still more rapid, the proportion of
earthy matter to that of water being much greater then than at other
times. Thus great, rapid rivers running through vast plains like these
gradually form levees in the course of many centuries, their channels
being defined and narrowed by their own deposits until the surface of
their waters, at least in times of flood, is raised above the level of
the surrounding country, often several feet. When the great swamps of
Louisiana shall have been drained and cultivated for ages, they too will
doubtless be fertilized and irrigated by canals, as the great plain
traversed by the Po now is. And here too, though the acres are generally
well cared for, I saw tracts of considerable extent which, from original
defect or unskillful management, stand below the water level of the
country, and so are given over to flags, bogs and miasma, when only a
foot or two of elevation is needed to render them salubrious and most
productive.

There are many more good dwellings on this plain than in the rural
portion of Lower Italy. These are generally built of brick, covered with
stucco or cement and white-washed, and, being nearly square in form, two
stories high, and without the long, sloping roofs common with us, are
rather symmetrical and graceful, in appearance. Their roofs are tiled
with a long, cylindrical brick, of which a first course is laid with the
hollow upward, and another over the joints of this with the hollow down,
conducting the water into the