Divination by water, said by Natalis Comes (d. 1582) to have been the invention of Nereus, ancient god of the sea. However, the term covers various methods of divination, ranging from forms of crystal gazing (using a large or small pool of water) to what is now known as radiesthesia —using as a pendulum a wedding ring suspended on a thread and held over a glass of water.
Hydromancy is, in principal, the same thing as divination by the crystal or mirror, and in ancient times a natural basin of rock kept constantly full by a running stream was a favorite medium.
The Jesuit scholar M. A. Del Rio (1551-1608) described one example of hydromancy in which the sucessor of Emperor Andronicus Comnenus was revealed.
The letters S.I. showed upon the water and the prediction was verified, for, within the time named, Isaac Angelus had thrown Andronicus to be torn to pieces by the infuriated populace of Constantinople. Since the devil spells backward, S.I., when inverted, would fairly enough represent Isaac, according to all laws of magic.
Del Rio cited several kinds of hydromancy. In one, a ring was suspended by a thread in a vessel of water. When the vessel was shaken, a judgment was formed according to the strokes of the ring against its sides.
In a second method, three pebbles were thrown into standing water and observations were drawn from the circles they formed. A third method depended upon the agitations of the sea.
A fourth divination was taken from the color of water and certain figures appearing in it. There arose a method of divination by fountains, since these were the waters most frequently consulted. Among the most celebrated fountains for this purpose were those of Palicorus in Sicily, which invariably destroyed the criminal who ventured to adjure them falsely in testimony of his innocence. A full account of their use and virtue is given by the Roman philosopher Macrobius (ca. 345-423 C.E.).
Pausanias (second century C.E.) described a fountain near Epidaurus, dedicated to Ino. On her festival certain loaves were thrown into the fountain. It was a favorable omen to the applicant if these offerings were retained; unlucky if they were washed up again. So, also, Tiberius cast golden dice into the fountain of Apomus, near Padua, where they long remained as a proof of the imperial monster's good fortune in making the highest throw.
Several other instances of divining springs were collected by the antiquary J. J. Boissard (1528-1602), and Del Rio ascribed to them the origin of a custom of the ancient Germans, who threw their newborn children into the Rhine, with a conviction that if they were spurious they would sink, if legitimate they would swim. This custom also sounds like a precursor of the seventeenth-century custom of "swimming witches," perhaps related to the Anglo-Saxon law, created by King Athelstan, of trial by water.
In a fifth method of hydromancy, certain mysterious words were pronounced over a cupful of water and observations were made upon its spontaneously bubbling. In a sixth method, a drop of oil on water in a glass vessel furnished a kind of mirror upon which many wonderful objects were said to become visible.
Clemens Alexandrinus mentioned a seventh kind of hydromancy in which the women of Germany watched the sources, whirls, and courses of rivers with a view to prophetic interpretation.
In modern Italy, acording to Del Rio, diviners were still to be found who wrote the names of any three persons suspected of theft upon a like number of little balls, which they threw into the water to determine the guilty party.
E. W. Lane, in his work An Account of the Manners and Customs of the Modern Egyptians (1836), testifies to the success of divination by a pool of water as practiced in Egypt and Hindustan. Lane witnessed the performance of this type of sorcery. The magician began by writing forms of invocation to his familiar spirits on six slips of paper. A chafing dish with some live charcoal in it was then procured and a boy summoned who had not yet reached puberty.
When all was prepared, the sorcerer threw some incense and one of the strips of paper into the chafing dish; he then took the boy's right hand and drew a square with some mystical marks on the palm. In the center of the square he poured a little ink, which formed the magic mirror, and told the boy to look steadily into it without raising his head. In this mirror the boy declared that he saw, successively, a man sweeping, seven men with flags, an army pitching its tents, and the various officers of state attending on the sultan. The rest is told by Lane himself:
"The sorcerer now addressed himself to me, and asked me if I wished the boy to see any person who was absent or dead. I named Lord Nelson, of whom the boy had evidently never heard, for it was with much difficulty that he pronounced the name after several trials. The magician desired the boy to say to the Sultan: 'My master salutes thee and desires thee to bring Lord Nelson; bring him before my eyes that I may see him speedily.' The boy then said so, and almost immediately added, 'A messenger has gone and brought back a man dressed in a black (or rather, dark blue) suit of European clothes; the man has lost his left arm.' He then paused for a moment or two, and looking more intently and more closely into the ink, said 'No, he has not lost his left arm, but it is placed on his breast.'
"This correction made his description more striking than it had been without it; since Lord Nelson generally had his empty sleeve attached to the breast of his coat; but it was the right arm that he had lost. Without saying that I suspected the boy had made a mistake, I asked the magician whether the objects appeared in the ink as if actually before the eyes, or as if in a glass, which makes the right appear left. He answered that they appeared as in a mirror. This rendered the boy's description faultless.
"On another occasion Shakespeare was described with the most minute exactness, both as to person and dress, and I might add several other cases in which the same magician has excited astonishment in the sober minds of several Englishmen of my acquaintance."
Lane's account may be compared with a similar one given by A. W. Kinglake, the author of Eöthen (1844).
Waite, Arthur Edward. The Occult Sciences. 1891. Reprint, Secaucus, N.J.: University Books, 1974.
A branch of crystalomancy (divination by water). One method was to toss an object into a full container of water and interpret either the image formed by it or else the sound it made striking the water. Another more complex method involved placing water in a silver vase on a clear, moonlit night. The light from a candle would be reflected onto the water by the blade of a knife and the inquirer would concentrate on the image formed in the water.
(See also pegomancy )