The Second British Epidemiology and Public Health Course was held from 19 to 25 August 1996 in Osaka as a satellite meeting for the 14th International Scientific Meeting of the International Epidemiological Association. Thirty-three researchers from 10 countries participated in the course. Professor Walter W Holland gave a special lecture about Snow on cholera during the course, and the lecture revealed that Henry Whitehead who was a junior priest at that time contributed to Snow's work to prevent the cholera outbreak in Golden Square in 1854. What John Snow did in his life are reviewed in detail in this paper.