Arte Magnetica.) However, a similar course of experiments over water led him to attribute to the rod the power of indicating subterranean springs and watercourses; “I would not affirm it,” he says, “unless I had established the fact by my own experience.”
Dechales, another Jesuit, author of a treatise on natural springs, and of a huge tome entitled “Mundus Mathematicus,” declared in the latter work, that no means of discovering sources is equal to the divining rod; and he quotes a friend of his who, with a hazel rod in his hand, could discover springs with the utmost precision and facility, and could trace on the surface of the ground the course of a subterranean conduit. Another writer, Saint-Romain, in his “Science dégagée des Chimères de l’École,” exclaims, “Is it not astonishing to see a rod, which is held firmly in the hands, bow itself and turn visibly in the direction of water or metal, with more or less promptitude, according as the metal or the water are near or remote from the surface!”
In 1659 the Jesuit Gaspard Schott writes that the rod is used in every town of Germany, and that he had frequent opportunity of seeing it used in the discovery of hidden treasures. “I searched
