Stains on Alchemical MSS: multispectral imaging

[Paul Ferguson]

Many of the most interesting manuscript stains are found in the bindings and folios of soiled, heavily-used medical and alchemical texts. Signs of this practical use may be obvious, such as burn marks from furnaces, but innocuous-looking stains (e.g. appearing to be water damage) may contain hidden information about medicinal or chemical solutions, or even heavy metal contamination, which is not evident by sight alone."

https://schoenberginstitute.org/2019/05/...l-imaging/