Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
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Credit
An itinerant surgeon extracting stones from a man's head; symbolising the expulsion of 'folly' (insanity), they are surrounded by a group of people. Pencil drawing by P. Quast, 1645. Attribution-NonCommercial 4.0 International (CC BY-NC 4.0). Source: Wellcome Collection.