During the 1853-54 epidemic, Farr gathered more statistical evidence. During focused study of the 1854 Broad Street cholera outbreak, the physician John Snow proposed what is now the accepted mechanism for transmission: people were infected by swallowing something, and it multiplied in the intestines. Snow discovered that people supplied with water from two companies in particular – namely, the Southwark & Vauxhall and the Lambeth water companies, which drew their water directly from the Thames – were especially likely to suffer. Farr took part in the General Board of Health's 1854 Committee for Scientific Enquiries. The conventional explanation for cholera was still multifactorial; Snow's view of cholera as solely caused by a pathogen was not accepted, though his evidence was taken seriously. Farr's research was detailed and showed an inverse correlation of mortality and elevation.