DIVINING-ROD. As indicated in the article Magic, Rhabdomancy, or the art of using a divining-rod for discovering something hidden, is apparently of immemorial antiquity, and the Roman virgula divina, as used in taking auguries by means of casting bits of stick, is described by Cicero and Tacitus (see also Divination); but the special form of virgula furcata, or forked twig of hazel or willow (see also Hazel), described by G. Agricola (De re metallica, 1546), and in Sebastian Munster's Cosmography in the early part of the 16th century, used specially for discovering metallic lodes or water beneath the earth, must be distinguished from the general superstition. The "dowsing" or divining-rod, in this sense, has a modern interest, dating from its use by prospectors for minerals in the German (Harz Mountains) mining districts; the French chemist M.E. Chevreul  assigns its first mention to Basil Valentine, the alchemist of the late 15th century. On account of its supposed magical powers, it may be taken perhaps as an historical analogue to such fairy wands as the caduceus of Mercury, the golden arrow of Herodotus's "Abaris the Hyperborean," or the medieval witch's broomstick. But the existence of the modern water-finder or dowser makes the divining-rod a matter of more than mythological or superstitious interest. The Schlagruthe (striking-rod), or forked twig of the German miners, was brought to England by those engaged in the Cornish mines by the merchant venturers of Queen Elizabeth's day. Professor W. F. Barrett, F.R.S., the chief modern investigator of this subject, regards its employment, dating as it does from the revival of learning, as based on the medieval doctrine of "sympathy," the drooping of trees and character of the vegetation being considered to give indications of mineral lodes beneath the earth's surface, by means of a sort of attraction; and such critical works as Robert Boyle's (1663), or the Mineralogia Cornubiensis of Pryce (1778), admitted its value in discovering metals. But as mining declined in Cornwall, the use of the dowser for searching for lodes almost disappeared, and was transferred to water-finding. The divining-rod has, however, also been used for searching for any buried objects. In the south of France, in the 17th century, it was employed in tracking criminals and heretics. Its abuse led to a decree of the Inquisition in 1701, forbidding its employment for purposes of justice.
In modern times the professional dowser is a "water-finder," and there has been a good deal of investigation into the possibility of a scientific explanation of his claims to be able to locate underground water, where it is not known to exist, by the use of a forked hazel-twig which, twisting in his hands, leads him by its directing-power to the place where a boring should be made. Whether justified or not, a widespread faith exists, based no doubt on frequent success, in the dowser's power; and Professor Barrett (The Times, January 21, 1905) states that "making a liberal allowance for failures of which I have not heard, I have no hesitation in saying that where fissure water exists and the discovery of underground water sufficient for a domestic supply is a matter of the utmost difficulty, the chances of success with a good dowser far exceed mere lucky hits, or the success obtained by the most skilful observer, even with full knowledge of the local geology." Is this due to any special faculty in the dowser, or has the twig itself anything to do with it? Held in balanced equilibrium, the forked twig, in the dowser's hands, moves with a sudden and often violent motion, and the appearance of actual life in the twig itself, though regarded as mere stage-play by some, is popularly associated with the cause of the water-finder's success. The theory that there is any direct connexion ("sympathy" or electrical influence) between the divining-rod and the water or metal, is however repudiated by modern science. Professor Barrett, who with Professor Janet and others is satisfied that the rod twists without any intention or voluntary deception on the part of the dowser, ascribes the phenomenon to "motor-automatism" on the part of the dowser (see Automatism), a reflex action excited by some stimulus upon his mind, which may be either a subconscious suggestion or an actual impression (obscure in its nature) from an external object or an external mind; both sorts of stimulus are possible, so that the dowser himself may make false inferences (and fail) by supposing that the stimulus is an external object (like water). The divining-rod being thus "an indicator of any sub-conscious suggestion or impression," its indications, no doubt, may be fallacious; but Professor Barrett, basing his conclusions upon observed successes and their greater proportion to failures than anything that chance could produce, advances the hypothesis that some persons (like the professional dowsers) possess "a genuine super-normal perceptive faculty," and that the mind of a good dowser, possessing the idiosyncrasy of motor-automatism, becomes a blank or tabula rasa, so that "the faintest impression made by the object searched for creates an involuntary or automatic motion of the indicator, whatever it may be." Like the "homing instinct" of certain birds and animals, the dowser's power lies beneath the level of any conscious perception; and the function of the forked twig is to act as an index of some material or other mental disturbance within him, which otherwise he could not interpret.
It should be added that dowsers do not always use any rod. Some again use a willow rod, or withy, others a hazel-twig (the traditional material), others a beech or holly twig, or one from any other tree; others even a piece of wire or watch-spring. The best dowsers are said to have been generally more or less illiterate men, usually engaged in some humble vocation.
Sir W. H. Preece (The Times, January 16, 1905), repudiating as an electrician the theory that any electric force is involved, has recorded his opinion that water-finding by a dowser is due to "mechanical vibration, set up by the friction of moving water, acting upon the sensitive ventral diaphragm of certain exceptionally delicately framed persons." Another theory is that water-finders are "exceptionally sensitive to hygrometric influences." In any case, modern science approaches the problem as one concerning which the facts have to be accepted, and explained by some natural, though obscure, cause.
See for further details Professor Barrett's longer discussion in parts 32 (1897) and 38 (1900) of the Proceedings of the Society for Psychical Research.
 La Baguette divinatoire (Paris, 1845).
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)