The Ghost Map: Chapter 7 Summary & Analysis

On the night of Thursday, September 7, the board of governors of St. James’s Parish had a meeting to discuss how the neighborhood would respond to the cholera outbreak. John Snow spoke at the meeting, insisting that the community needed to remove the pump as soon as possible. The Board was skeptical. They knew that everybody loved Broad Street water, and many of them subscribed to the miasma theory, not Snow’s waterborne theory. But Snow’s arguments were very persuasive, and in the end the Board voted to close down the well.

On the morning of Friday, September 8, the Broad Street pump handle was removed. The deaths would continue in Soho for another week, and none of the newspapers reported that the Board had removed the pump handle. Indeed, the Friday paper included a miasmic story about how changes in the weather were going to improve the cholera situation. However, as the days went on, it became clear that the worst of the outbreak was over—few people were contracting the disease. In all, some seven hundred people near the Broad Street pump had died in less than two weeks.

The removal of the Broad Street pump handle probably didn’t seem like a major event. But it was quietly momentous—a public institution had made an informed intervention in a cholera outbreak, based on “a scientifically sound theory.” Reason triumphed over the disease. However, many people were furious that the pump had been shut down. Meanwhile, Sir Benjamin Hall commissioned an investigation into the Soho neighborhood, attributing the disease to factors such as slaughterhouses and “peculiarities of ventilation.” Hall ordered that researchers should study the pipe system beneath the neighborhood, but overall, his assignment reflected a loyalty to miasma theory, which acted as a kind of intellectual “strait-jacket.” Hall took the waterborne theory of cholera into account, but it wasn’t a priority for him—for months, he and his research team asked the wrong questions about why the outbreak happened.

At first, Henry Whitehead thought the pump handle’s removal was a foolish choice. He was so displeased, in fact, that he vowed to disprove the waterborne theory of cholera—and in the end, his opposition to Snow’s theory proved invaluable, since it strengthened Snow’s theory. Whitehead began by interviewing elderly people who’d survived the cholera epidemic—“What kind of pestilence,” he wondered, “spares the old?” Meanwhile, Snow began writing a monograph on cholera, which he published in the fall.

As Whitehead continued with his research, he became aware of the lack of correlation between sanitary conditions and mortality rates on Broad Street. He then composed his own monograph on the cholera outbreak of 1854; in it, one can see Whitehead struggling with the theological meaning of so many deaths. He claims, for example, that God had a greater plan in mind for London—by sending a plague of cholera, God was drawing mankind’s attention to the problem of poverty. But in addition to his theological musings, Whitehead offered some important data in his monograph.

In late November, the St. James Vestry founded a committee to investigate the Broad Street cholera outbreak; however, the committee was weakened by the fact that Sir Benjamin Hall refused to share his Board’s findings with anyone else. Hall’s refusal turned out to be a good thing, though, as it encouraged the committee to hire Henry Whitehead, the only local with an encyclopedic knowledge of the outbreak. On the committee, Whitehead offered a vigorous attack on John Snow’s theory that the Broad Street well was to blame for the outbreak, pointing out that many of the cholera victims who’d survived the outbreak attributed their survival to drinking from the well.

As Whitehead conducted further research, he began to come around to John Snow’s theory. Some of the families who Whitehead interviewed later remembered that their deceased loved ones had drunk from the well, contrary to what they’d told Whitehead initially. In particular, Whitehead realized that young children were the well’s most frequent patrons—many of them had to fetch water from the well as part of their chores. He further realized that many elderly men and women had survived the outbreak not because of their inner constitutions, but simply because they lived alone and hadn’t had anyone bring them water from the well.

Whitehead was coming around to John Snow’s theory, but he still had some objections. First, he wondered why the outbreak hadn’t occurred near some other well with a reputation for inferior water. Second, he couldn’t explain why some Soho residents had survived the outbreak after drinking extra water from the well. Finally, Whitehead couldn’t explain why he’d survived the outbreak, considering that he’d drunk Broad Street water. Furthermore, studies had concluded that the Broad Street well wasn’t connected to the sewer lines in any way. Whitehead received a copy of Snow’s monograph, and later wrote Snow a letter listing his objections to Snow’s theory. Whitehead wondered why the cholera outbreak had plateaued so quickly—if the disease was waterborne, and if people were passing rice-water diarrhea, wouldn’t the spread of the disease have accelerated?

As the data about the cholera outbreak continued to pile up, Whitehead began to believe Snow’s theory. He began searching for an “index case”—i.e., the earliest cholera victim of 1854. While studying the data, he came across the medical report for baby Lewis, who’d experienced diarrhea before dying. Whitehead interviewed Sarah Lewis and learned that she’d thrown soiled diapers into a cesspool. Whitehead realized that the baby’s cholera evacuations must have been deposited near the Broad Street well. He commissioned surveyors to examine the cesspool, and the surveyor found that it had, indeed, leaked into the well. Earlier investigations had missed the cesspool connection, perhaps because they were too focused on miasma. Whitehead realized that the surveyor had answered his objections to Snow’s theory. The reason the cholera body count hadn’t grown exponentially was that only the Lewis family could access the cesspool—therefore, baby Lewis’s waste was the only source of cholera in the well, and the cholera agent wasn’t growing exponentially.

The St. James Vestry Committee issued a report hypothesizing that, just as John Snow had argued, the cholera outbreak was caused by contamination of the Broad Street well. The Committee’s report further attacked the popular miasma theory of the era. And yet, around the same time, Benjamin Hall’s own Committee issued a report on the epidemic concluding that Snow’s theory was unverifiable and unlikely. The Board of Health Committee was so blinded by miasma theory that it couldn’t accept any other explanation for cholera. The Committee’s report on the outbreak analyzed a stunning number of factors (including humidity, wind velocity, and atmospheric pressure), all of which reflected a miasmatic conception of the disease.

Hall’s Committee’s report hit on one problem on its miasmatic hypothesis: the death of Susannah Eley, miles away from Broad Street. The Committee explained Eley’s death by saying that the water she’d received from her sons was “impure with organic contamination.” However, the Committee stressed that, during an epidemic, contamination in the atmosphere can also contaminate the water. This was “circular argumentation at its most devious.” Thus, miasma theory survived the 1854 outbreak intact.

Perhaps the last person to die of the 1854 outbreak was Thomas Lewis, who succumbed to his illness on September 19, 1854. After baby Lewis’s death, the Lewis family stopped emptying cholera-infected waste into the cesspool—however, after Thomas took ill, Sarah Lewis began emptying his diarrhea into the cesspool, infecting the Broad Street pump once more. Had Snow not convinced the authorities to remove the pump handle, the outbreak probably would have continued.