John Snow, Asiatic Cholera and the inductive-deductive method - republished

The person-to-person spread of cholera: Lecture 2.

 In the last post, we summarised Snow’s life.

John Snow, Asiatic Cholera and the inductive-deductive method - republished

In today’s post, we follow Snow’s description of the cholera epidemics of his time. Subsequently, we describe Snow’s deduction on the incubation period and the problems defining stable numerators and denominators.

The Snow series is an educational course. We hope you will recognise our efforts by donating to TTE or becoming a paying subscriber, as writing the series took a lot of time and effort.  

The attention of John Snow was attracted by the 1848 outbreak of cholera, which he says first appeared in London in the autumn of 1848. He starts off On the Mode of Communication of Cholera, 2nd edition, 1855 (MCC2) with a history of what was then known of Asiatic cholera. Snow charted its migration first in the Indian subcontinent and its subsequent spread to China, the Philippines and other parts of South East Asia. 

Snow points out that it is impossible to give a detailed account without describing what we would now call a setting, but its spr…