partial barrier between the sweet water and the stagnant, rising up to
within a few feet of the surface. This barrier is overgrown with flags
and reeds, where it is shallow. Here it is possible to sail along the
sweet water within an arrow-shot of the swamp. Nor, indeed, would the
stagnant mingle with the sweet, as is evident at other parts of the
swamp, where streams flow side by side with the dark or reddish water;
and there are pools, upon one side of which the deer drink, while the
other is not frequented even by rats.

The common people aver that demons reside in these swamps; and, indeed,
at night fiery shapes are seen, which, to the ignorant, are sufficient
confirmation of such tales. The vapour, where it is most dense, takes
fire, like the blue flame of spirits, and these flaming clouds float to
and fro, and yet do not burn the reeds. The superstitious trace in them
the forms of demons and winged fiery serpents, and say that white
spectres haunt the margin of the marsh after dusk. In a lesser degree,
the same thing has taken place with other ancient cities. It is true
that there are not always swamps, but the sites are uninhabitable
because of the emanations from the ruins. Therefore they are avoided.
Even the spot where a single house has been known to have existed, is
avoided by the hunters in the woods.

They say when they are stricken with ague or fever, that they must have
unwittingly slept on the site of an ancient habitation. Nor can the
ground be cultivated near the ancient towns, because it causes fever;
and thus it is that, as I have already stated, the present places of the
same name are often miles distant from the former locality. No sooner
does the plough or the spade turn up an ancient site than those who work
there are attacked with illness. And thus the cities of the old world,
and their houses and habitations, are deserted and lost in the forest.