Powder of sympathy

Frontispiece illustration of 'Sympathia'- (Powder of Sympathy) Wellcome

Powder of sympathy was a form of early pseudoscientific navigation and alchemy, in the 17th century in Europe, whereby a remedy was applied to the weapon that had caused a wound with the aim of healing the injury it had made. Weapon salve was a preparation, again applied to the weapon, but based on material from the wounded patient rather than on any remedy for the wound.