It is interesting to follow up some of the controversies among scientific men with regard to the weapon ointment, for they serve to show how the remedy came to maintain its prominence for so long. Podmore, in his "Mesmerism and Christian Science" (London, 1909), tells the story of the controversy between Goclenius, a professor of medicine at the University of Marburg, who published as the Inaugural Thesis for his professorship, a treatise on the "Weapon Salve," and Father Roberti, a Jesuit scientist and philosopher, whose final treatise in the controversy was entitled after the lengthy fashion of titles in that day, "Goclenius Corrected Out of His Own Mouth; or, The Downfall of the Magnetic Cure and the Weapon Salve." The decision of the controversy was eventually referred to the great physician of the time. Van Helmont, who decided that both disputants were partly wrong, the Jesuit erring most, but that above all Goclenius should distinguish between the cases when the weapon had blood on it and when it had not. When there is blood on the weapon, he held, then the salve is always effective; when there is not, then much stronger remedies were required. In both cases, of course, the salve or ointment was applied to the weapon. In the midst of this discussion of the points at issue, it is interesting to note Van Helmont's opinion with regard to many curious things used in medicine at that time. He insists that Goclenius makes a mistake in attributing therapeutic power alone to the moss taken from the skull of a condemned criminal who had been hung in chains. This material, under the name of _usnea_, was apparently quite popular in prescriptions for various chronic ills, and especially those that we now recognize as prolonged neurotic affections. Van Helmont emphasizes the fact that the experience of all physicians shows that material taken from the heads of condemned criminals executed in other ways, as, for instance, those broken on the wheel, may be just as effective. Van Helmont conceived of the magnetic and sympathetic feeling as a natural process. All the force of the stars might be concentrated in objects that had been beneath their beams for a long time, and this might be communicated in some wonderful way to patients so as to supply defects of vitality. Such defects of vitality Van Helmont's prescriptions actually were compensating, but the source was in the patients themselves--that reservoir of surplus energy which remains unused unless some strong suggestion brings it out.