https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/13953535
Franz Joseph Gall leading a discussion on phrenology with five colleagues, among his extensive collection of skulls and model heads. Coloured etching by T. Rowlandson, 1808.
Original public domain image from Wellcome Collection
Public DomainFree CC0 image for Personal and Business use