On October 16, 1846, the American dentist William T.G. Morton successfully demonstrated the use of inhaled ether anaesthesia at Massachusetts General Hospital in Boston, an event widely considered a turning point in modern surgery. But this record may have to be rewritten after new evidence emerged that in the 14th century AD, Chinese surgeons were making their own anaesthetics from plants. Their use had previously been recorded in ancient Chinese texts, but now the first physical evidence...