Dr John Snow and Reverend Whitehead

Written by Peter Daniel and David Markoff

Cholera first developed in the Indian subcontinent but was spread into Russia, China, and Germany in the early 19th century mostly by sailors. By 1832 it had reached London and began to ravage the city’s poorest districts, where poor sanitation led inevitably to the greatest death tolls. The panic and misery cholera brought hung like a noose around London’s neck, growing tighter every year. It wasn’t until halfway through the century that people truly began to work to discover the roots of the epidemic.

In the mid 19th century, London became a staging point for an epic battle between its citizens and the killer disease of cholera. In only a matter of decades, four terrible outbreaks erupted in London, wreaking havoc and leaving behind a trail of death and destruction. Thousands had already perished from the disease and thousands more were destined to die if a solution was not discovered soon. It was fortunate that hope emerged in the form of two very different men, Dr. John Snow and Reverend Henry Whitehead. These men, with starkly different systems of belief, were able to set aside their differences in the interest of the common good. Together, they combined their respective knowledge—of medicine and of the surrounding community—to begin the fight back against cholera. They worked tirelessly to protect the people of Soho, and indeed, all of London from further threat of the deadly disease.


John Snow was born in York on 15 March, 1813 to humble beginnings. The son of a farmer, John Snow was the eldest of nine children but showed promise in his early life through his passion for learning. Snow’s intense focus on his studies soon became the focal point of his life and nothing interested him more than the burgeoning profession of medicine. At the tender age of fourteen he became apprenticed to a surgeon and from that point his love of medicine only continued to grow. He encountered his first case of cholera in 1832 when he was treating those stricken with the disease at a coalmine in Killingworth. The poor sanitation in the mine did not escape Snow’s sharp observation yet with no formal background into the history of cholera he could do nothing but file the memory away.

In his younger years, Snow was not a registered physician and was in essence little more than a town apothecary. In order to receive a full and accredited medical education he traveled to London, where he settled in Soho and began formal medical training at the University of London. Snow received his degree in 1836 and quickly became a rising star in the field of anesthesiology. Cholera remained an interest of Snow’s but not his primary focus. Yet, as his reputation became better known—Snow had administered aid to Queen Victoria during the birth of Prince Leopold in 1854—and his finances now more secure, Snow began to concentrate more of his time to the study of cholera.

Snow soon began formulating a revolutionary theory as to how cholera was spread. At this time, popular opinion stated that the disease was spread through the inhalation of air from a poisonous and cloud-like miasma. Yet Snow remained unconvinced. Why would cholera not affect the lungs if it were an airborne disease? Why did it instead attack the bowels and cause dehydration and excessive diarrhea? Snow began to devise a theory that cholera was spread through the ingestion of polluted water. At this time Londoners received their drinking water from the Thames, into which the city’s sewers disgorged their contents every day. The conclusion was that the citizens of London were, in essence, drinking their own waste.

In 1849, after several investigations, John Snow published a medical pamphlet entitled ‘On the Mode of Communication of Cholera’ in which he outlined his theory, writing:

‘If the cholera had no other means of communication than those which we have been considering it would be constrained to confine itself chiefly to the crowded dwellings of the poor, and would be continually liable to die out accidentally in a place, for want of the opportunity to reach fresh victims.’

Snow, however, had difficulty finding proof to reinforce his theory and for that reason many chose to reject it. Members of Parliament were frank in their disbelief and many of them refused to debate the issue simply because the idea of consuming water polluted with human waste was far too disgusting and embarrassing a topic for them to consider.

Snow also had other, more influential, critics to deal with. The miasma theory prevailed amongst the educated elite, whilst the notion that cholera was a punishment from God for their sins was the most prevalent view amongst ordinary Londoners. One such proponent of this vengeance theory was the Reverend Henry Whitehead—a figure somewhat obscured in the history of cholera by Snow’s overarching scientific presence. Yet without the Reverend Whitehead most of Snow’s theories would not have been supported by the substantial body of proof they needed to become credible.

The Reverend Henry Whitehead led a very different life from that of Snow. Whitehead was born in the small seaside town of Ramsgate to a relatively wealthy family. He attended primary school at the prestigious Chatham House and upon graduation was accepted into Lincoln College at Oxford. Whitehead, like Snow, possessed a great love of learning but instead of choosing a secular profession, gave his life instead to the church. Within a few years of his graduation, Whitehead was ordained in 1851 as an Anglican minister and was given the position of Vicar of St. Luke’s Church in Soho.

Known for his empirical knowledge and excellent memory, Whitehead became the figurative shepherd of his community. When the cholera outbreak of 1854 began in earnest he became very concerned for his parishioners, many of whom were looking to the church for answers as to why such an awful disease had fallen upon their parish. Whitehead was desperate for a way to calm the fears of his parishioners and actively began searching for answers to placate them. Whitehead reasoned that if cholera was a visitation of the vengeance of God then there must also be some manner in which to alleviate God’s anger and—in turn—the disease. Whitehead had heard about Snow’s theory and believed that he could prove him wrong. However, as he investigated each cholera death that occurred in his parish he found that rather than disproving Snow’s theories they were supporting them.

It was at this time that John Snow also began searching for the proof that would vindicate his theory that cholera was a waterborne illness. Snow’s investigations took him to St. Luke’s parish, where he often went door-to-door, collecting information from the residents and mapping out where the main outbreaks occurred. Yet Snow’s information was incomplete. He did not possess the local knowledge that would allow himself to fully integrate his research into the community. Whitehead, however, did—and though they were of opposing viewpoints as to the origins of cholera, they decided to work together.

One example of their collaboration comes in the case of Frances Lewis, a five-month-old child who was the daughter of Police Constable Thomas Lewis and his wife Sarah Lewis, who lived at 40, Broad Street opposite the local water pump. Frances contracted cholera and died on the 2nd September 1854 at the beginning of the epidemic. She might have appeared to have been just one of many victims of the outbreak that Snow came across but for the additional information that Whitehead provided him with as he knew the family. Her mother, Sarah was able to tell them that Frances had contracted the disease on the 24th August which led Snow to believe that she was the index case or instigator of the outbreak. He discovered that Sarah had washed the baby girl’s soiled clothes and emptied the dirty water into a cesspool in front of her house. This innocuous act had inadvertently led to the outbreak of cholera as the cesspit was later found to have leaked into the water that was drawn from the Broad Street pump. It was Whitehead’s knowledge that led Snow to the index case but some people still claimed that the deaths in Soho were as a result of people breathing in ‘bad air’ or miasma. Snow needed evidence to contradict them and Whitehead was able to help him find it.

Whitehead was able to tell Snow about a widow living in Hampstead, who had died of cholera on the same day as Frances Lewis, the 2nd September, and her niece, who lived in Islington, who had succumbed with the same symptoms the following day. Since neither of these women had been near Soho for a long time, it was impossible that they could have contracted the disease through breathing in the polluted air of the area. Intrigued, Dr Snow rode up to Hampstead to interview the widow’s son. He discovered from him that the widow had once lived in Broad Street, and that she had liked the taste of the well-water there so much that she had sent her servant down to Soho every day to bring back a large bottle of it for her by cart. The last bottle of water—which her niece had also drunk from—had been fetched on 31st August, at the very start of the Soho epidemic. This was just the sort of evidence he needed to prove the argument of the miasmatists wrong.

He found further evidence through the case of the St James’s Workhouse in Poland Street, which was only round the corner from the Broad Street pump and would therefore have been a prime site for cholera to take hold. However, he discovered that of the 530 inmates, only five people had contracted cholera as no one from the workhouse drank the pump water, for the building had its own well. Further proof of his theory came from the workers at the local brewery. Among the 70 workers at the Lion Brewery, where the men were given an allowance of free beer every day so never drank water at all, there were no fatalities at all.

With all of this information gathered, Snow was able to map the incidence to visually demonstrate that most of the deaths had occurred in areas closest to the Broad Street pump. Convinced he had sufficient evidence to disprove his doubters he arranged to present his case to the St James’s Vestry, who were the local authority responsible for the area of Soho. Together with the Rev Whitehead, he was able to persuade them that the outbreak was linked to the polluted water found at the Broad Street pump and was able to persuade them to disable it by removing its handle, although by then the epidemic had begun to subside.

Despite this minor victory Snow’s theory that cholera was a waterborne disease did not become widely accepted. Though he tried to impart this knowledge onto members of the government, public health officials were reluctant to agree with Snow’s theory. His theories were not readily accepted and most did not even want to consider the fact that London, for some time, had been ingesting the very waste it was so intent on throwing out. After all, only twenty-two years previously a panel had been called before the Royal Commission on the Water Supply of the Metropolis. There, several doctors testified that “the impregnating ingredients of the Thames are as perfectly harmless as any spring water of the purest kind in common life: indeed, there is probably not a spring, with the exception of Malvern, and one or two more, which are so pure as Thames water.” Sadly Dr John Snow passed away in June, 1858 and did not see the vindication of his work.

That summer, London was gripped by ‘The Great Stink.’ Nothing had been done to stop sewage being pumped into the Thames and a heat wave had created such foul conditions that M.Ps were nearly forced to abandon the Houses of Parliament because of the awful smell. This finally spurred the government into action who commissioned Joseph Bazalgette to create his sewage system; Londoners were soon to have access to clean drinking water which would save them from further outbreaks of cholera.

However, in 1866, before Bazalgette’s system was complete, one final outbreak of the disease ravaged the one area left unprotected-east London. The time had come for the Reverend Whitehead—the former nonbeliever—to take centre stage. Whitehead was now the main authority on the earlier Broad Street outbreak and when the Bishop of London called for volunteers from among the clergy who had previous experience with cholera, to help with the east London outbreak, Reverend Whitehead was among those who responded. His assistance helped investigators look for a waterborne source to the outbreak and led to the discovery that sewage from the River Lea had polluted the reservoirs of the East London Water Company, and so caused the epidemic. The water-borne explanation had now been proved beyond doubt, and eliminating the source of pollution though the completion of Bazalgette’s system of sewers in 1871 ensured this was the final outbreak in the capital. Finally, Dr John Snow’s vision of the future foretold to the Reverend Henry Whitehead had been proved right:

”You and I may not live to see the day, and my name may be forgotten when it comes, but the time will arrive when great outbreaks of cholera will be things of the past; and it is the knowledge of the way in which the disease is propagated which will cause them to disappear.”