This 2012 episode from prior hosts Sarah and Deblina covers dentist Horace Wells. At an exhibition in 1844 he became certain that nitrous oxide could revolutionize medicine. He tried to demonstrate his findings, but things didn't go as planned.

Robert Moses and the Shaping of New York, Part 2
42:12

Robert Moses and the Shaping of New York, Part 1
41:59

SYMHC Classics: Eradication of Smallpox
43:25