In the deserts of Lop in Asia, such apparitions of wandering spirits are often perceived, as you may read in the travels of Marco Polo the Venetian. If someone happens to lose his companions, these devils call him by name and imitate his companions’ voices to lead him astray.

Jeroni Pau, in his book on the mountains of Spain, tells of a great mountain in Cantabria where such apparitions may be seen. Lavater and Cicogna give a variety of examples of spirits and wandering devils of this kind.

Sometimes they sit beside the highway to make people fall and their horses stumble and shy as they ride—if you believe the account of that holy man Ketell in William of Newburgh. Ketell had received a special, divinely bestowed gift of seeing devils and “conversing fearlessly with spirits,” without harm. If a man curses or spurs his horse for stumbling, they rejoice heartily at it. They play many such pretty tricks.

Underground devils are as common as the rest and do as much harm. Olaus Magnus, book 6, chapter 19, distinguishes six kinds, some larger and some smaller. These, says Münster, are commonly seen around metal mines. Some are harmful; others do no harm. In many places miners consider the sight of them good luck, a sign of treasure and rich ore.

Georgius Agricola, in On Creatures Living Underground, chapter 37, identifies two especially notable kinds, which he calls Getuli and Cobali. Both dress like miners and often imitate their work. Their task, Pictorius and Paracelsus think, is to guard the treasure in the earth so that it is not all discovered at once.

Besides this, Cicogna asserts that they frequently cause those terrible earthquakes which often swallow up not only houses but entire islands and cities. He gives many instances in his third book, chapter 11.

The last kind inhabits the region around the earth’s centre, to torture the souls of the damned until Judgment Day. Some suppose that they enter and leave through places around Etna, Lipari, Mount Hekla in Iceland, Vesuvius, Tierra del Fuego, and the like, because many shrieks and fearful cries are continually heard thereabouts, and apparitions of dead people, ghosts and goblins commonly appear.

Thus the Devil reigns, and in a thousand different shapes, “like a roaring lion, continually seeks someone to devour,” 1 Peter 5. Through earth, sea, land and air he remains as yet unconfined. Some, however, hold that his proper dwelling is the air—all the space between us and the moon—for those spirits that transgressed least, and hell for the wickedest.

“Here they are held as if in prison until the end of the world, then to be thrust into a more dreadful place,” as Augustine holds in City of God, chapter 22; book 14, chapters 3 and 23. But wherever he may be, he rages while he can. To comfort himself with other people’s falls, as Lactantius thinks, he does all he can to bring them into the same pit of destruction as himself.

For human misery, calamity and ruin are the Devil’s banquet dishes. Through many temptations and various devices he seeks to enslave our souls. The lord of lies, says Augustine, himself deceived, seeks to deceive others. The ringleader of all wickedness, he would treat the whole world as he treated Eve and Cain, Sodom and Gomorrah.

Sometimes he tempts through greed, drunkenness, pleasure, pride, and so on; he leads astray, casts down, saves, kills, protects, and rides some people as they ride their horses. He plans our overthrow and seeks our destruction in every way.

Although he often professes to benefit humanity and claims to be a god by curing various diseases, “restoring health to the sick and sight to the blind,” as Augustine declares, City of God, book 10, chapter 6—as Apollo, Aesculapius and Isis did in ancient times—though he turns plagues aside, helps people in war and professes to promote their happiness, still “nothing is more impure or criminal, nothing more hostile to the human race”: nothing so impure, nothing so pernicious.

This is plain enough from their tyrannical and bloody human sacrifices to Saturn and Moloch, which are still practised among those barbarous Indians; from their various deceits and frauds to keep people obedient; their false oracles and sacrifices; their superstitious imposition of fasting, poverty, and the like; their heresies; and their superstitious observance of rules about foods and times.

By these means they crucify mortal souls, as will be shown in our treatise on religious melancholy. “He is permitted to do evil for a little while yet,” as Bernard puts it. By God’s permission he rages for a time, later to be confined to hell and darkness, “which is prepared for him and his angels,” Matthew 25.

How far their power extends is hard to determine. I will briefly show you what the ancients believed about their effects, strength and workings. Plato in the Critias, and his followers after him, declared that these spirits or devils were humanity’s rulers and guardians, our lords and masters, as we are of our cattle.

They govern provinces and kingdoms through oracles, omens, dreams, rewards and punishments, prophecies, inspirations, sacrifices and religious superstitions, which take as many forms as there are kinds of spirits. They send war, plague, peace, sickness, health, scarcity and plenty, “standing here beside us even now, watching and judging,” and so on.

This appears in the histories of Thucydides, Livy and Dionysius of Halicarnassus, and in many others full of their astonishing stratagems. The Roman and Greek states therefore adored and worshipped them as gods, with prayers, sacrifices, and so forth. In a word, “They seek nothing more than human fear and wonder.” As another writer puts it, “Words cannot express the ungovernable passion with which evil spirits covet dominion over humanity and divine worship.”