Book I CONTAGION 67

moreover, to observe, also, certain other conditions of the lower
atmosphere. For we must look for danger when south winds9
blow strong and for a long period; or when one sees abnormal
mists hanging over a certain region; or finally, if a brownish and
dusty sort of atmosphere has for a long time made the sun look
gloomy.

But one needs especially to be on one's guard when one ob—
serves that certain winds are blowing from a quarter where the
plague prevails; and one should not merely fear, but flee, when
objects placed in the open air, such as provisions, linen and the
like, contraect a kind of decay and mildew. But the waters
too give their own signs, when rivers overflow, and the inunda—
tionsö? last for a long time, and then leave behind them marshy
and muddy places; also when the sea discharges on to its shores
many dead fish.

The earth also, when it brings to birth a vast number of in—
sects, warns us that putrefactions have been conceived; and,
unless these have been completely absorbed into those animal
organisms, they indicate that contagions still lurk beneath the
earth. Locusts, above all, portend these contagions, for when
they swarm in countless and almost infinite numbers, this is a
sign not only that serious putrefaction has already occurred,
'but it is often the cause of a new putrefaction. For they rise
like a monstrous army and fly into certain districts, and when
they have devastated these far and wide, they often die there.
From this cause there soon follows an immense corruption; for
instance, like that which as we read, happened in Africa in the
year 118, when locusts in incredible numbers had arrived on
the coasts and died there; the same is recorded in France in
864; and finally, in Italy, in 1478, in the territories of Ferrara,
Mantua, Verona and Brescia, and in the neighboring localities;
after the arrival of a huge multitude of locusts, & lamentable
pestilence soon followed. And this would have happened some
years ago also, had not the clemency of a Gracious God and the
vigilance of mortals provided against it. For at that time we
saw a vast number of those insects, more, one may suppose, than
had ever been seen before. A great swarm of them alighted in
the country districts of our Northern Italy, another swarm flew
towards France, and seven days were not enough for the mi—
gration of so great a host. 'The corpses of men slain in battle
often produce the same effect.