On this day, February 14, in 1929, Sir Alexander Fleming first published his discovery of penicillin in the British Journal of Experimental Pathology. 

Alexander Fleming was photographed by Karsh in July, 1954, likely at St. Mary’s Hospital, Paddington, London. The laboratory in which Fleming discovered and tested penicillin is preserved there as the Alexander Fleming Laboratory Museum.

That month Karsh also photographed Douglas Fairbanks Jr., Augustus John, Benjamin Britten, a host of actors, and many others.