Jan Purkyne (1787-1869) was a Czech anatomist and physiologist.
He is best known for his discoveries concerning the senses, published in books such as Observations and Experiments Investigating the Physiology of Senses and New Subjective Reports about Vision.
As an aside, he was also interested in the psychological effects of such substances as camphor, opium, belladonna and turpentine!
He also experimented with nutmeg when he "washed down three ground nutmegs with a glass of wine and experienced headaches, nausea, euphoria, and hallucinations that lasted several days". Plus ca change.
His light experiments were safer.
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