https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/13957704
A scholar in a surgeon's workroom with a jar of spirits containing Saint Michael defeating a dragon with a barbued tonge; representing the scholar's knowledge of chemistry enabling surgeons to heal, by setting the beneficent force of alkalis against the noxious force of acids. Etching by P.P. Bouche, ca. 1686.
Original public domain image from Wellcome Collection
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