The root of the _mano de sapo_ is usually taken fresh. There is another indispensable precaution: while undergoing this treatment it is necessary to abstain from all sexual intercourse for three days after the first inoculation, for two days after the second, and for one day after the third. For the inoculation a large snake’s tooth, that is to say, one of the fangs, is employed, and the fangs of the most poisonous snakes, such as the rattle-snake (_cuatro narices_), are selected. The snake must be killed on a _Friday_, and the fangs extracted the same day. The same fang may serve for several years! The inoculation is commenced on the dorsal surface of the left foot; care must be taken to avoid coming into contact with a vein. The skin is torn with the point of the fang, so that it bleeds a little, and the incision is in the shape of a square. From the left foot the operator passes to the right wrist (anterior surface), then to the right foot (dorsal surface), and left wrist (anterior surface), always changing from one side of the body to the other. Operations are continued on the left thigh, then on the right arm, right thigh, and left arm; in this way all the limbs are inoculated. On the body an inoculation is made in the centre of the sternum; another is made in the nape, and a final one in the centre of the forehead. The finishing touch is given with the semblance of a square incision in the tongue. At least seven series of similar inoculations are necessary to protect a man from the spells of the serpent, and at the same time to confer upon him the faculty of curing by suction the bites of the venomous snakes that are most dreaded. During the whole of the period in which the Indian thus submits to successive inoculations, his health shows no noteworthy derangement. He feels a slight headache and a strange inclination towards alcoholic drinks. But when the moon is at the full, then indeed, an excitement which is dangerous in another way takes possession of him. His cerebral faculties become over-excited, and he feels that his senses are deserting him; his eyes become bloodshot, and he is pursued and tormented by an irresistible impulse to bite. He has itching sensations in his gums, his mouth burns, and salivation is greatly increased. He feels that he is going to give way to the necessity to bite, and then he flees to the woods, where he bites the trees viciously, tears their bark and discharges his venom. His poisonous saliva mingles with the sap, and, surprising phenomenon, the tree withers and dies! Woe to the man or animal who happens to be bitten by a _Curado de Culebra_ in a fit of passion. The victim will die as quickly as if he had been bitten by a snake!