# Is "On the Mode of Communication of Cholera" by John Snow a First Edition?

> **Quick answer.** A first edition of On the Mode of Communication of Cholera by John Snow (John Churchill, 1849) is identified by: First edition, a slim octavo pamphlet of 31 pages per the National Library of Medicine's catalogued first-edition copy, setting out Snow's original hypothesis that cholera is transmitted through contaminated water rather than through 'miasma' (bad air).

**Checklist — a true first has these:**
- First edition, a slim octavo pamphlet of 31 pages per the National Library of Medicine's catalogued first-edition copy, setting out Snow's original hypothesis that cholera is transmitted through contaminated water rather than through 'miasma' (bad air)
- The 1849 first edition contains no map
- Snow's now-famous 'Broad Street pump' map of the 1854 Soho outbreak, engraved by Charles Cheffins, appears for the first time only in the greatly enlarged second edition of 1855 (162 pages), which also adds Snow's comparison of cholera death rates between the Southwark & Vauxhall and Lambeth water companies
- Publisher imprint reads John Churchill
- Not a book-club edition (see below)

| | |
|---|---|
| Author | John Snow |
| Publisher | John Churchill |
| Year | 1849 |
| True first | — |
| Format | Hardcover (trade) |
| Key point | First edition, a slim octavo pamphlet of 31 pages per the National Library of Medicine's catalogued first-edition copy, setting out Snow's… |
| Book-club edition exists? | — |

## Points of issue
First edition, a slim octavo pamphlet of 31 pages per the National Library of Medicine's catalogued first-edition copy, setting out Snow's original hypothesis that cholera is transmitted through contaminated water rather than through 'miasma' (bad air). The 1849 first edition contains no map. Snow's now-famous 'Broad Street pump' map of the 1854 Soho outbreak, engraved by Charles Cheffins, appears for the first time only in the greatly enlarged second edition of 1855 (162 pages), which also adds Snow's comparison of cholera death rates between the Southwark & Vauxhall and Lambeth water companies.

## Source
New Mexico Literacy Project — Is *On the Mode of Communication of Cholera* by John Snow a first edition? https://newmexicoliteracyproject.org/first-edition/on-the-mode-of-communication-of-cholera
CC BY 4.0. Part of the Canonical First-Edition Points of Issue dataset (https://newmexicoliteracyproject.org/api/first-edition-titles.json). Last reviewed 2026-07-04.