Although the connection between germ and disease was proposed quite early, it was not until the late-1800s that the germ theory was generally accepted. The miasmatic theory was challenged by John Snow, suggesting that there was some means by which the disease was spread via a poison or morbid material (orig: *materies morbi*) in the water.[29] He suggested this before and in response to an epidemic on Broad Street in central London in 1854.[30] Because of the miasmatic theory's predominance among Italian scientists, the discovery in the same year by Filippo Pacini of the bacillus that caused the disease was completely ignored.