The Philosophy of Natural Magic, by Henry Cornelius Agrippa, L. W. de Laurence ed. [1913], at sacred-texts.com
Now, the soothsayings of flashes and lightnings, and of wonders, and how monstrous and prodigious
things are to be interpreted, the prophets and priests of Hetruscus have taught the art. For they have ordained sixteen regions of the heavens and have ascribed Gods to every one of them, besides eleven kinds of lightning, and nine gods which should dart them forth, by showing rules for understanding the signification of them. But as often as monstrous, prodigious and wondrous things happen, they do presage, as is most certain, some great matter. Now, their interpreter must be some excellent conjector of similitudes, as also some curious searcher, and of them who at that time are employed about the affairs of princes and provinces. For the celestials take such care only for princes, peoples and provinces that before the rest they might be prefigured and admonished by stars, by constellations and by prodigies. Now, if the same thing, or the like, hath been seen in former ages, we must consider that very thing and what happened after that, and according to these, to foretell the same, or the like, because the same signs are for the same things, and the like for like. So prodigies have come before the birth and death of many eminent men and kings, as Cicero makes mention of Midas, a boy, into whose mouth whilst he was sleeping, the ant put corns of wheat, which was an omen of great riches. So bees sat upon the mouth of Plato when he was sleeping in the cradle, by which was foretold the sweetness of his speech. Hecuba, when she was bringing forth Paris, saw a burning torch, which should set on fire Troy and all Asia. There appeared unto the mother of Phalaris the image of Mercury pouring forth blood upon the earth, with which the whole house was overflowed. The mother of Dionysius dreamed she brought forth a satyr, which prodigious dream the event that followed made good. The wife of Tarquinius Priscus, seeing a flame lick the head of Servius Tullius, foretold that he should have the kingdom.
[paragraph continues] In like manner, after Troy was taken, Æneas disputing with Anchises, his father, concerning a fight, there appeared a flame licking the head of the crown of Ascanius and doing him no hurt. Which thing, seeing it did portend the kingdom to Ascanius, persuaded him to depart, for monstrous prodigies did forerun great and eminent destruction. So we read in Pliny that M. Attilius and C. Portius, being consuls, it rained milk and blood, which did presage that a very great pestilence should the next year overspread Rome. In Lucania it rained spongeous iron, and in the year before Marcus Crassus was slain in Parthia, with which, also, all the soldiers of Lucania, being a very numerous army, were slain. L. Paulus and C. Marcellus, being consuls, it rained wool about the castle of Corisanum, near which place, a year after, T. Annius was slain by Milus. And in the wars of Denmark, the noise of arms and the sound of a trumpet was heard in the air. And Livy, concerning the Macedonian wars, saith, in the year when Annibal died it rained blood for two days. Concerning the second Punic war, he saith that water mixed with blood came down from heaven like rain at the time when Annibal did spoil Italy. A little before the destruction of Leuctra, the Lacedemonians heard a noise of arms in the temple of Hercules, and at the same time in the temple of Hercules the doors that were shut with bars opened themselves, and the arms that were hanged on the wall were found on the ground. The like events may be prognosticated of other like things, as oftentimes in times past something hath been foretold of them. But concerning these, also, the judgments of the celestial influences must not be neglected, concerning which we shall more largely treat in the following chapters.