It is also necessary to state, that many of the practices which superstition has at different times suggested, have not been alike absurd; nay, some of them have even possessed, by accident, natural powers of considerable efficacy, whilst others, although, ridiculous in themselves, have actually led to results and discoveries of great practical importance. The most remarkable instance of this kind upon record is that of the _Sympathetic_ powder of Sir Kenelm Digby,[27] Knight of Montpellier. Whenever any wound had been inflicted, this powder was applied to the weapon that had inflicted it, which was, moreover, covered with ointment, and dressed two or three times a-day.[28] The wound itself in the mean time was directed to be brought together, and carefully bound up with clean linen rags, but, ABOVE ALL, TO BE LET ALONE for seven days; at the end of which period the bandages were removed, when the wound was generally found perfectly united. The triumph of the cure was decreed to the mysterious agency of the sympathetic powder which had been so assiduously applied to the weapon; whereas, it is hardly necessary to observe, that the promptness of the cure depended upon the total exclusion of air from the wound, and upon the sanative operations of nature not having received any disturbance from the officious interference of art; the result, beyond all doubt, furnished the first hint, which led surgeons to the improved practice of healing wounds by what is technically called the _first intention_. The rust of the spear of Telephus, mentioned in Homer as a cure for the wounds which that weapon inflicted, was probably _Verdegris_, and led to the discovery of its use as a surgical application. Soon after the introduction of Gunpowder, _cold water_ was very generally employed throughout Italy, as a dressing to gun-shot wounds; not however from any theory connected with the influence of diminished temperature or of moisture, but from a belief in a supernatural agency imparted to it by certain mysterious and magical ceremonies, which were duly performed immediately previous to its application: the continuance of the practice, however, threw some light upon the surgical treatment of these wounds, and led to a more rational management of them.