temporary deyo

Ingredients

powdered charcoal, pressed grape skins, oil soot, olive oil, pitch, colophony, gum ammoniac, gum arabic, honey

Preparation Steps

Original Recipe Text

Take powdered charcoal of the skins of pressed grapes, oil soot (e.g., from olive oil), pitch, colophony, and gum ammoniac. These are mixed with the charcoal powder, then kneaded with gum arabic and honey. The mixture is formed into thin sheets. For use, these sheets are dissolved in water to obtain a beautiful writing fluid (p. 30).

Evidence

"Maimonides gave the recipe for the temporary deyo which may be erased: Take powdered charcoal of the skins of pressed grapes, oil soot, for example from olive oil, pitch, colophony, and gum ammoniac. It is all mixed with the charcoal powder, then kneaded with gum arabic and honey."

Remarks

This ink was specifically designed to be erodible. In two to three years, the writing becomes faint and then disappears without a trace (p. 30).