Dr. J. Davy examined and analyzed some of these “stones,” and found one of them to be a piece of bone partially calcined. When applied to the tongue or to any other moist surface it adhered firmly. Another, which lacked all absorbent or adhesive power, was said to have saved the life of four men. It therefore appears that while some of the “snake-stones” really possessed some possible curative virtues, others were esteemed only because of a superstitious belief in their magical properties. Kaempfer, writing in 1712, informs us that these stones should always be used in pairs, and applied successively to the wound.[465] The belief in the efficacy of such stones is still general in India, and one of the varieties is supposed to be found in the head of the adjutant bird.[466] Francisco Redi[467] describes the extraordinary healing power attributed to stones obtained from the heads of certain serpents, called by the Portuguese “_cobras de capello_,” found throughout Hindostan and Farther India. These stones are claimed to be an infallible remedy for the bites and stings of all kinds of venomous reptiles or animals, and likewise for wounds made by poisoned arrows, etc. He repeats the usual tales of their adhering powerfully when applied to the bite or wound, and clinging to it like a cupping-glass until they had absorbed all the poison, when they would fall off spontaneously, leaving the man or animal sound and free. Then follows the account of steeping the stones in milk to remove the poison, the milk assuming a color between yellow and green. These wonderful stones and the narrations concerning them had been brought to Italy by Catholic missionaries, who seemed to have entire faith in their powers; so that Redi says they offered to prove the accounts by any number of experiments, such as would satisfy the most incredulous, and prove to medical men that Galen was correct when he wrote (Chapter XIV, Book I) that certain medicines attract poison as the magnet does iron. For this purpose a search for vipers, etc., was recommended; but, owing to the season being later and colder than usual, none could at that time be obtained, as they had not emerged from their winter quarters. An experiment was therefore substituted, after much consultation among the learned men of the Academy of Pisa, whereby oil of tobacco was introduced into the leg of a rooster. This was regarded as one of the most fatal of such substances, and was administered by impregnating a thread with it to the width of four fingers and drawing it through the punctured wound. One of the monks forthwith applied the stone, which behaved in the regular manner described. The bird did not recover, but it survived eight hours, to the admiration of the monks and other spectators of the experiment. [Illustration: