# Weapon-salve

**Unguentum armarium*; the powder of sympathy*

**Known today as.** An ointment, with moss from a dead man’s skull, human fat, blood, and other ingredients, applied to the weapon that caused a wound.

Kind: Compound

## What was it used for?

To heal a wound at a distance by anointing the blade, while the wound was merely kept clean.

## What does modern science say?

Counted now among the pseudosciences; the answer of its first English critic, in 1631, was that a wound kept clean would heal without it.

## Pharmacognosy and toxicology

- **vitriol**: of Digby’s powder of sympathy, dissolved in water with the blood-stained garter laid in it
- **moss from a skull, mummy, human fat, bloodstone**: in the ointment, by Fludd’s and Bacon’s accounts
- **nothing applied to the wound**: which was washed and bound

**Mechanism.** The salve went on the weapon and the wound was washed, bound, and left alone; Foster himself argued that a wound kept clean “will cicatrice without his Weapon-Salve.” In Digby’s cure the vitriol never touched the patient: the bloody garter lay in vitriol water, and the wounded man was told to cast away his plasters and keep the wound clean. Francis Bacon set down the claims, though “not fully inclined to beleeve it,” and liked best that it would cure a beast as well as a man, because that “subiecteth the Matter, to an Easie Triall.”

**Dose.** None reached the patient.

**Standing.** The clearest case in the Materia Medica of a remedy that worked by doing nothing; see the clinical reading.

## What did the older authorities say?

**Paracelsus.** Was credited with inventing it.

**William Foster and Robert Fludd.** Fought over it in print in 1631, the parson calling it witchcraft and the physician defending it as natural magic.

**Sir Kenelm Digby.** His discourse on the “powder of sympathy,” made “in a Solemne Assembly of Nobles and Learned Men at Montpellier,” was printed in English in 1658.

## Sources

- Foster, W. (1631). *Hoplocrisma-Spongus: or, A Sponge to wipe away the Weapon-Salve*.
- Digby, K. (1658). *A Late Discourse… Touching the Cure of Wounds by the Powder of Sympathy*.
- Fludd, R. (1631). *Doctor Fludds Answer unto M. Foster, or, The Squeesing of Parson Fosters Sponge*. London: Nathanael Butter.
- Bacon, F. (1627). *Sylva Sylvarum: or A Naturall Historie*. London: William Lee.
- “Powder of sympathy.” *Wikipedia* (read 2 October 2026).
- Digby, K. (1658). *A Late Discourse Touching the Cure of Wounds by the Powder of Sympathy*.

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*Weapon-salve.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-03. The Thinking Press. https://thethinkingpress.org/materia-medica/weapon-salve

Historical description, not medical advice.