[De epidemia et peste]

An epidemic will be predicted to be coming when the aforementioned signs, or one or several of them, appear, namely when at the end of summer and in the beginning of autumn there are many fiery impressions and comets, which the philosopher calls jumping goats, abyssal gashes, sanguine colors, and falling stars. For then a great resolution occurs in bodies, as these things do not happen except from an inflammable exhalation. The second sign is a multitude of some animals on the earth that are not customary, such as frogs, toads, and locusts. The third sign is when southern and subsolan winds multiply and a multitude of clouds, vapors, and rains appear without effect. When all these things, or some of them, appear, the complexion of the winter is corrupted, and consequently, an epidemic supervenes on the winter. If, however, the spring were cold and dry without rain, and southern winds blew, and there is a disturbance of the air and its haze for about eight days, then it clears, and then it is disturbed, and this happens frequently, then the epidemic will come in the summer, and with this, hot days and cold nights. Similarly, when the summer is not hot with a multitude of mists, so that the air is not cleared but is rather turbid. Similarly, when on the same day there is sometimes cold and sometimes heat, one must expect autumnal illnesses, that is, unequal ones, as in the third book of Aphorisms, aphorism five. Similarly, when for two or three days there is heat, and as many days of cold. It should be noted that when the putrefaction of the air happens, sometimes those existing in good air are harmed more than those in bad. As it has been seen frequently concerning those incarcerated and captive at the bottom of towers, and concerning those inhabiting valleys, that they do not die, and those inhabiting good air