# Crow’s gall

**Fiel di corvo**

**Known today as.** The bile of a crow.

Kind: Animal

## What did Canale use it for?

With jasmine oil for anointing (ch. 9).

## What does modern science say?

Animal galls were used in ancient eye medicine. Bile salts are detergents and can thin mucus, which may be why galls seemed to clear the eyes; the practice is abandoned.

## Pharmacognosy and toxicology

- **bile acids**: cholic and chenodeoxycholic
- **biliverdin**: the green of bird bile

**Mechanism.** Bird bile, applied in oil: bile acids are detergents that would irritate the skin and nothing more. The Chinese bear bile of the same tradition has a real drug in it, ursodeoxycholic acid, now synthesised; crow’s bile has not been studied and there is no reason it should be.

**Dose.** None.

**Standing.** A sympathetic ingredient; nothing in modern use.

## What lore surrounds it?

The crow, as a bird of omen and of the gallows, lent its parts to the magical pharmacy; the choice of a crow’s gall for anointing the bewitched is sympathy of the darkest bird against the dark.

## What did the older authorities say?

**Dioscorides and Galen.** Give the galls of many animals, the hyena, the ox, the goat, the partridge, for dimness of the eyes; the crow’s bile belongs to this long tradition of gall as a medicine for sight.

**The Book of Tobit.** Tobias cures his father’s blindness with the gall of a fish, by the angel’s instruction, the scriptural warrant for every later gall.

## Sources

- Tobit 6:4–9; 11:10–13.
- Dioscorides, *De materia medica* II.
- Hagey, L. R., et al. (1993). “Ursodeoxycholic acid in the Ursidae: biliary bile acids of bears, pandas, and related carnivores.” *Journal of Lipid Research* 34.

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*Crow’s gall.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-01. The Thinking Press. https://thethinkingpress.org/materia-medica/crows-gall

Historical description, not medical advice.