On Continuous Molecular Changes,
More Particular in Their Relation to Epidemic Diseases: 

Being the Oration Delivered at the 80th Anniversary of The Medical Society of London. 

 by John Snow, M.D.
London: John Churchill, Princes Street, Soho, England, 1853


This work of John Snow was presented and written at age 40, the same year he administered chloroform for childbirth to Queen Victoria. It offers his views on cholera and other epidemic diseases that were troublesome during the mid-1800s.  The writings illustrate his manner of epidemiologic thinking, and how he used available clinical and population-based evidence to address the potential etiology of selected infectious diseases. 

- Ralph R. Frerichs