John Snow: Anaesthetist to a Queen and Epidemiologist to a NationBMJ 1995; 311 doi: https://doi.org/10.1136/bmj.311.7012.1107 (Published 21 October 1995) Cite this as: BMJ 1995;311:1107
- Dorothy Porter
David A E Shephard York Point Publishing, P O Box 843 Cornwall, PE, Canada COA 2HO, pounds sterling15, pp 347 ISBN 1 57087 103 5
David Shephard's heroic account of the Yorkshire lad, dedicated to vegetarianism and temperance, who ultimately gave Victoria “that blessed chloroform” provides us with new insights into the man who did not actually remove the handle of the Broad Street pump. Shephard aims to portray Snow as a “complete physician” by showing how he linked his clinical practice to both laboratory and epidemiological scientific research.
Snow's attraction to the novel practice of anaesthesia in the 1840s was a logical extension of his long held interest in the chemistry of respiration. In his early years as a practitioner in London he presented papers to the Westminster Medical Society on the effects of carbon dioxide inhalation and the causes of infantile asphyxia. His extensive anaesthetic practice—4000 chloroformed patients—was combined with the study of the action of volatile agents in the blood in order to discover the safest method.
Not only did this give him a sufficient reputation to be asked to anaesthetise Queen Victoria during the births of Princes Arthur and Leopold and Princess Beatrice, it also, according to Shephard, laid the foundations on which the modern discipline of anaesthesia is based.
His studies of the effects of gas on human physiology led Snow to reject the common mid-19th century belief that all disease was smell. He demonstrated that the symptoms of cholera resulted from a local lesion in the alimentary canal. This meant that it could not be caused by an atmospheric poison, which would produce general symptoms from blood poisoning. Furthermore, his study of two London localities in the 1848-9 epidemic proved that the disease was passed from the gut of one person to another through materials contaminated by infectious excretions, such as soiled bed linen, corrupted water, or food prepared by polluted hands.
Snow drew the fire of the profession when he concluded that the causative agent was a living being which reproduced itself in the intestine, but he escaped the ignominy experienced by his contemporary, William Budd, whose fungal theory of the disease entity was completely rejected by the Royal College of Physicians. During the 1854 cholera epidemic Snow convinced all that the Southwark and Vauxhall Water Company's polluted water was spreading the disease. By this time he was confidently promoting his theory that all diseases were living “cellular” micro-organisms.
Shephard thus concludes that Snow's career, though short because of his death at 45, was spectacularly innovative. His admiration for his subject does, however, limit Shephard's ability to put Snow in context within the social history of the Victorian medical profession—and its relations with science and the state—which is crucial to this story. Nevertheless, he has managed to highlight the continuity of Snow's reasoning, which united clinical experience with scientific analysis and provides, Shephard suggests, a virtuous medical model still relevant for the 20th century.—DOROTHY PORTER, Wellcome research senior lecturer in the history of medicine, Birkbeck College, University of London