Weapon salve

Fludd, Robert. Dr Fludds answer unto M. Foster or, the squesing of Parson Fosters sponge, ordained by him for the wiping away of the weapon-salve. .. London , 1631. 

Debus, Allen George. Robert Fludd and the use of Gilbert s De Magnete in the weapon-salve controversy. J Hist Med Allied Sci 19, no. 4 (Oct 1964) 389-417. 

Eco s story is, of course, a fantasy but the weapon salve controversy was not. In his own contribution, van Helmont concluded that a certain magnetic sympathy existed not between the weapon and the wound, but between the wound and the blood left on the weapon. Something similar to this type of magnetic sympathy, he felt, also accounted for the effects of sacred relics. These... 

The toxicity of plants, venoms, and other poisons used in armaments posed perils to those who wielded them, and the mythology and the history of poison weapons is rife with examples of accidental self-injury and unintended collateral damage. The use of windborne toxins also involved blowback problems, as acknowledged by Kautilya in his Arthashastra. He cautioned that protective salves and other remedies must be applied before deploying poisonous smokes. Toxic weapons are notoriously difficult to control and often resulted in the destruction of noncombatants as well as soldiers, especially in siege situations. 

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