https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/13982736
A physician in traditional costume holding an ointment jar is supervising an apprentice who is mixing a concoction in a pot over a fire, Germany 1500. Heliotype.
Original public domain image from Wellcome Collection
Public DomainFree CC0 image for Personal and Business use