The Value of Maps John Snow and the 1854 London Cholera Epidemic

Grade 9 Geography – Assignment #2 The Value of Maps – John Snow and the 1854 London Cholera Epidemic

Tuthill, Kathleen. 2003. John Snow and the Broad Street Pump: On the Trail of an Epidemic. Cricket. 31(3), pp. 23-31, Nov. 2003

British doctor John Snow could not convince other doctors and scientists that cholera, a deadly disease, was spread when people drank contaminated water until a mother washed her baby’s diaper in a town well in 1854 and touched off an epidemic that killed 616 people.

Dr. Snow, an obstetrician with an interest in many aspects of medical science, had long believed that water contaminated by sewage was the cause of cholera. Cholera is an intestinal disease than can cause death within hours after the first symptoms of vomiting or diarrhea. Snow published an article in 1849 outlining his theory, but doctors and scientists thought he was on the wrong track and stuck with the popular belief of the time that cholera was caused by breathing vapors or a “miasma in the atmosphere”.

The first cases of cholera in England were reported in1831, about the time Dr. Snow as finishing up his medical studies at the age of eighteen. Between 1831 and 1854, tens of thousands of people in England died of cholera. Although Dr. Snow was deeply involved in experiments using a new technique, known as anesthesia, to deliver babies, he was also fascinated with researching his theory on how cholera spread.

In the middle 1800s, people didn’t have running water or modern toilets in their homes. They used town wells and communal pumps to get the water they used for drinking, cooking and washing. Septic systems were primitive and most homes and businesses dumped untreated sewage and animal waste directly into the Thames River or into open pits called “cesspools”. Water companies often bottled water from the Thames and delivered it to pubs, breweries and other businesses.

Dr. Snow believed sewage dumped into the river or into cesspools near town wells could contaminate the water supply, leading to a rapid spread of disease. In August of 1854 Soho, a suburb of London, was hit hard by a terrible outbreak of cholera. Dr. Snows himself lived near Soho, and immediately went to work to prove his theory that contaminated water was the cause of the outbreak. “Within 76 metres of the spot where Cambridge Street joins Broad Street there were upwards of 500 fatal attacks of cholera in 10 days,” Dr. Snow wrote, “As soon as I became acquainted with the situation and extent of this irruption (sic) of cholera, I suspected some contamination of the water of the much-frequented street-pump in Broad Street.”

Dr. Snow worked around the clock to track down information from hospital and public records on when the outbreak began and whether the victims drank water from the Broad Street pump. Snow suspected that those who lived or worked near the pump were the most likely to use the pump and thus, contract cholera. His pioneering medical research paid off. By using a geographical grid to chart deaths from the outbreak and investigating each case to determine access to the pump water, Snow developed what he considered positive proof the pump was the source of the epidemic.

John Snow – Page 1 Besides those who lived near the pump, Snow tracked hundreds of cases of cholera to nearby schools, restaurants, businesses and pubs. According to Snow’s records, the keeper of one coffee shop in the neighborhood who served glasses of water from the Broad Street pump along with meals said she knew of nine of her customers who had contracted cholera. A popular bubbly drink of the time was called “sherbet”, which was a spoonful of powder that fizzed when mixed with water. In the Broad Street area of Soho, that water usually came from the Broad Street pump and was, Snow believed, the source for many cases.

Snow also investigated groups of people who did not get cholera and tracked down whether they drank pump water. That information was important because it helped Snow rule out other possible sources of the epidemic besides pump water. He found several important examples. A workhouse, or prison, near Soho had 535 inmates but almost no cases of cholera. Snow discovered the workhouse had its own well and bought water from the Grand Junction Water Works.

The men who worked in a brewery on Broad Street which made malt liquor also escaped getting cholera. The proprietor of the brewery, Mr. Huggins, told Snow that the men drank the liquor they made or water from the brewery’s own well and not water from the Broad Street pump. None of the men contracted cholera. A factory near the pump, at 37 Broad Street, wasn’t so lucky. The factory kept two tubs of water from the pump on hand for employees to drink and 16 of the workers died from cholera.

The cases of two women, a niece and her aunt, who died of cholera puzzled Snow. The aunt lived some distance from Soho, as did her niece, and Snow could make no connection to the pump. The mystery was cleared up when he talked to the woman’s son. He told Snow that his mother had lived in the Broad Street area at one time and liked the taste of the water from the pump so much that she had bottles of it brought to her regularly. Water drawn from the pump on 31 August, the day of the outbreak, was delivered to her. As was her custom, she and her visiting niece took a glass of the pump water for refreshment, and according to Snow’s records, both died of cholera the following day.

Snow was able to prove that the cholera was not a problem in Soho except among people who were in the habit of drinking water from the Broad Street pump. He also studied samples of water from the pump and found white flecks floating in it, which he believed were the source of contamination. On 7 September 1854, Snow took his research to the town officials and convinced them to take the handle off the pump, making it impossible to draw water. The officials were reluctant to believe him, but took the handle off as a trial only to find the outbreak of cholera almost immediately trickled to a stop. Little by little, people who had left their homes and businesses in the Broad Street area out of fear of getting cholera began to return.

Despite the success of Snow’s theory in stemming the cholera epidemic in Soho, public officials still thought his hypothesis was nonsense. They refused to do anything to clean up the cesspools and sewers. The Board of Health issued a report that said, “we see no reason to adopt this belief” and shrugged off Snow’s evidence as mere “suggestions.”

For months afterward Snow continued to track every case of cholera from the 1854 Soho outbreak and traced almost all of them back to the pump, including a cabinetmaker who was passing through the area and children who lived closer to other pumps but walked by the Broad Street pump on their way to school. What he couldn’t prove was where the contamination came from in the first place.

John Snow – Page 2 Officials contended there was no way sewage from town pipes leaked into the pump and Snow himself said he couldn’t figure out whether the sewage came from open sewers, drains underneath houses or businesses, public pipes or cesspools.

The mystery might never have been solved except that a minister, Reverend Henry Whitehead, took on the task of proving Snow wrong. The minister contended that the outbreak was caused not by tainted water, but by God’s divine intervention. He did not find any such proof and in fact, his published report confirms Snow’s findings. Best of all, it gave Snow the probable solution to the cause of the pump’s contamination. Reverend Whitehead interviewed a woman, who lived at 40 Broad Street, whose child who had contracted cholera from some other source. The child’s mother washed the baby’s diapers in water which she then dumped into a leaky cesspool just one metre from the Broad Street pump, touching off what Snow called “the most terrible outbreak of cholera which ever occurred in this kingdom.” A year later a magazine called The Builder published Reverend Whitehead’s findings along with a challenge to Soho officials to close the cesspool and repair the sewers and drains because “in spite of the late numerous deaths, we have all the materials for a fresh epidemic.” It took many years before public officials made those improvements.

In 1883, a German physician, Robert Koch, took the search for the cause of cholera a step further when he isolated the bacterium Vibrio cholerae, the “poison” Snow contended caused cholera. Dr. Koch determined that cholera is not contagious from person to person, but is spread only through unsanitary water or food supply sources, a major victory for Snow’s theory. The cholera epidemics in Europe and the United States in the 19th century ended after cities finally improved water supply sanitation.

The World Health Organization (WHO) estimates 78 percent of the people in Third World countries are still without clean water supplies today, and up to 85 percent of those people don’t live in areas with adequate sewage treatment, making cholera outbreaks an ongoing concern in some parts of the world.

Today, scientists consider Snow to be the pioneer of public health research in a field known as epidemiology. Much of the current epidemiological research done at the U.S. Centers for Disease Control, which still uses theories such as Snows’ to track the sources and causes of many diseases.

John Snow – Page 3 Figure 1. John Snow’s Map of the Deaths by Cholera in relation to the Broad Street water pump

John Snow – Page 4 Grade 9 Applied Geography - Assignment #2 Fighting Cholera with Maps Teacher Instructions Preview of Main Ideas Five hundred people, all from the same section of London, England, died of cholera within a ten- day period in September 1854. Dr. John Snow, a local physician, had been studying the spread of cholera for some time. An early example of medical geography is Dr. Snow’s use of maps to prove his long-held theory that cholera was a waterborne infection. Using mapping techniques similar to Snow’s, students will analyze maps to see if they can determine the sources of cholera in London. This activity can help students learn how mapping techniques can be used to understand social issues and to solve problems.

Geography Themes: Location, Place, Human/Environment Interaction, Movement

Materials One copy of each handout for each student: - Handout 1: Background Information - Handout 2: Map of Cholera Deaths - Handout 3: Map of Cholera Deaths and Locations of Water Pumps - Handout 4: Dataset – Deaths due to Cholera

Overhead projector and transparency of each map (Optional)

Objectives Students will  Examine maps to draw conclusions about cholera deaths in London  Understand how maps can provide useful information about an issue  Understand how maps can be used to solve problems

Opening the Lesson Have students use atlases to locate Great Britain and London. Tell students that in September 1854, during the last great cholera epidemic in Great Britain, 500 people—all from the same section of London, England—died of the disease within a ten-day period. Bacteria were still unknown, and the people and political leaders were panicking.

Distribute or read Handout 1 to students.

Developing the Lesson Dr. John Snow was a British doctor who had been studying cholera for many years. In trying to determine the source of cholera, Dr. Snow located every cholera death in the Soho district of London by marking the location of the home of each victim with a dot on a map. Distribute the handout “Map of Cholera Deaths” and have students focus on the spatial distribution of cholera deaths.

Have students formulate questions about the map. (For example, why is there a cluster of deaths near Broad Street? Why are there fewer deaths on Regent Street?) Ask students to speculate as to the spread of cholera deaths. Have students predict the location of pumps. Record student responses on the chalkboard. After discussing the distribution of cholera deaths, distribute Handout 3, “Map of Cholera Deaths and Locations of Water Pumps.” Ask students to formulate

John Snow – Page 5 additional questions—for example, why were there so many deaths near Broad Street? (Explain to students that water pumps were the only source of drinking water.)

Concluding the Lesson Ask students what course of action they would take if they were city officials presented with the information on Dr. Snow’s map. Then tell students that Dr. Snow requested city officials to remove the handle from the Broad Street pump, making it impossible to get water there. After his request was granted, the number of new cholera cases in the area declined dramatically—almost to zero. Dr. Snow’s theory was confirmed: Cholera was associated with the drinking water supply, and the water was carrying the disease to its victims.

Assessing Student Learning Ask students to list the steps that Dr. Snow took in solving the cholera problem in London. Ask them to answer these questions: What if the locations of deaths and locations of water pumps (Handout 3) were not clustered? How might this have altered Dr. Snow’s research and course of action? Have students identify particular problems and issues that might be better understood through map development and analysis—for example, the occurrence of auto accidents, tornadoes, earthquakes, or crimes.

Extending the Lesson Discuss some questions that are important to medical geographers: Where are diseases found? How do diseases spread? Is there a pattern to the spread of disease? Are some diseases more common in some environments than in others? Are the locations of health-care facilities important? Are they related to patterns of disease? Have students research the spread of specific diseases, for example, AIDS, smallpox, malaria, or typhoid, then use medical atlases to research and plot the spread of diseases on blank outline maps.

Give students (or have them acquire) information on traffic accidents in your community. (This information should be available from local police or the county sheriff’s office.) Plot the accidents on a map and have students formulate questions and draw conclusions based on the data. Perhaps there is a need for a stop sign, traffic signal, or lower speed limit in a particular area.

Additional Reading Snow, John. Snow on Cholera. New York: Hafner, 1965.

John Snow – Page 6 Grade 9 Applied Geography – Inquiry and Skill Development Assignment #2 - Fighting Cholera with Maps Handout #1 - Background Information

Cholera (also called Asiatic cholera) is a severe, infectious disease of the small intestine. It is marked by heavy diarrhea, vomiting and muscle cramps. It can result in coma and death.

The disease is contracted by ingesting food or drink—usually water—that is contaminated with a bacterium found in feces (human or animal wastes). After cholera bacteria are swallowed, they multiply in the small intestine resulting in an infection that interferes with normal intestinal functions. Frequent diarrhea results. This can cause a great deal of fluid loss —water and essential salts—in a short period of time. In some cases, three to four gallons of fluid loss has been reported in a 24-hour period.

Today, recovery is almost certain with prompt treatment such as replenishing the body’s fluids until the diarrhea stops or administering antibiotics such as tetracycline. However, cholera is common in impoverished tropical and semitropical developing nations where poor sanitation and contaminated water are common. A vaccine can provide partial protection for a limited time, but the vaccine cannot prevent the spread of infection on a large scale. About 50 percent of all those who contract cholera in these regions are not treated and die of the disease.

Clean food and drinking water can prevent cholera outbreaks.

History – Cholera in London For centuries, cholera was confined to India, but in the early 19th century, it began to spread to other parts of Asia, Europe and the Americas.

In September 1854 during the last great cholera epidemic in Great Britain, 500 people in London, England died of the disease within a ten-day period. Bacteria were still unknown, and as such, the cause of the cholera outbreak was also unknown. People were panicking.

The political leaders of London asked Dr. John Snow, a renowned scientist and doctor, to determine the source of cholera. Dr. Snow made the following observations.  London was a highly industrialized city  London was overcrowded and the Soho District was densely populated  Food was often poorly stored  Garbage removal practices were very poor and human garbage tended to collect on street corners and in alleyways  Houses in the Soho District did not have internal plumbing for water -- water was obtained from neighbourhood wells  Houses did not have internal plumbing for the removal of human sewage – bathroom facilities were poorly maintained outhouses in alleyways off the streets  Human sewage was collected in open sewage pools  Many people kept large animals within the city (e.g., horses) and the animal waste collected on the streets

Task Dr. Snow has hired you as a technical assistant. The year is 1854. Dr. Snow has given you a dataset of deaths due to cholera and a grid map for the Soho District of London. You must advise Dr. Snow on what you have learned and what you think he should do next.

Instructions  Read the handout Background Information  Highlight or record the important information (e.g., How do humans contract cholera?)  Map the data (Handout #3) on the blank Grid Map of the core of London. Your map must be complete (e.g. Legend, Title).

John Snow – Page 7  Answer the following questions. Explain your answers completely.

1. When you look at the map, what do you see? What does the map show / tell you? What is your interpretation of the mapped dataset?

2. Use ONE WORD to describe the distribution of the deaths?

3. Why is it important to graph the entire dataset?

4. What is useful about the information about deaths due to cholera in the prison? Provide two ideas with your answer.

5. Are there any apparent differences between Broad Street and the other streets in the district? Provide one observation.

6. What do you HYPOTHESIZE as the possible reason for the deaths at Broad Street?

7. Why might some deaths be occurring in locations far from Broad Street? Provide one reason for your answer.

8. What do you recommend Dr. Snow do next? Why? Provide two reasons for your recommendation.

9. Let’s alter you map. The locations of death and water pumps are not clustered together. How might this information have altered Dr. Snow’s research and course of action?

10. In a summary paragraph, explain why mapping this dataset was important. In other words, what is the value of the map?

Assignment – John Snow and the Cholera Story Marking Strategy Total Marks Your Mark Map - Completeness 10 - Accuracy 10 - All map components 10 Written Work - Questions 1-5 10 - Questions 6-7 6 - Question 8-10 12 Title Page 2 TOTAL 60

John Snow – Page 8 Handout #3 – Dataset – Deaths due to Cholera Grid Locations - John Snow and Cholera Deaths due to Cholera - Grid Locations Open Water Sewage Pump Pool Brewery Locations Location Location Day 1 L18 S4 G6 J15 G6 S14 P6 G6 Q15 M8 2 R14 P13 R11 O11 T10 W14 Q14 O11 W10 R11 T6 P1 X13 3 O15 O9 T14 O14 P14 K15 O16 N16 N6 R11 D7 D2 X14 4 M13 N16 P11 O13 T10 R11 N13 R15 J11 M15 P7 Y11 X15 5 O11 L9 R14 T14 M8 Q15 J15 N9 M9 O15 G11 P13 Y13 6 L17 Q16 M16 U17 N16 J16 O17 J19 X19 M17 P14 N18 Y14 7 N16 S13 Q12 T18 P17 P11 M17 N17 U12 S15 Y14 X22 Y15 8 M14 O12 L13 N11 N14 R15 O14 N13 S19 U14 I16 I26 9 R13 S14 O12 N14 N14 M11 P16 N16 R15 S13 Z18 10 N14 Q15 P13 O12 M11 M11 L17 L17 L18 J16 J20 11 O16 O22 O9 T9 M8 G22 T9 T9 M9 L11 D21 12 N12 Q14 Q13 N17 K17 S13 L11 O15 N13 X19 L26 13 N12 N14 N14 M14 R15 Q12 N13 N15 R16 M15 14 U20 O15 M12 P15 M14 Q15 S12 J15 S12 L17 15 O14 O8 M17 P8 P8 M8 P6 P9 Q20 U20 16 Q15 P17 J19 M15 N14 R11 P11 Q15 O13 L18 17 P8 O18 L17 R16 P16 M13 N14 P15 P12 O22 18 T9 R16 R14 M13 S15 K15 M16 Q12 R20 L21 19 O13 T15 O14 K12 K12 P17 K15 R16 O5 O15 20 O23 Q13 K15 P8 R14 R15 O12 Q16 J15 U20 21 R15 J12 R15 M17 R14 R13 O12 U14 U14 O16 22 N17 L13 N16 N12 N13 N17 P9 N9 L17 O16 23 P11 K20 N14 N14 N12 R14 G19 U20 K14 L11 24 M14 P11 M14 N17 Q15 H19 N15 N12 P23 K17 25 P13 U20 M14 J16 W17 Q16 K14 K14 L18 R20 26 L18 O17 L13 L17 M15 Q20 N16 N12 M15 S19 27 M11 Q15 N14 Q15 N13 G6 R15 M17 L18 O8 28 N13 N16 Q17 L13 M17 M11 J11 Q15 M8 M11 29 L13 S19 N8 M13 Q16 P15 L8 P9 F17 M13 30 R8 U6 Q15 N16 L13 R16 R14 T21 U20 31 P14 T21 L18 L9 M8 R15 R11 N11 L18 32 M13 R20 O8 P6 L8 T13 L9 T13 33 N13 L18 T21 N23 P9 P11 M11 34 N13 P6 N9 P13 P11 K9 U20 35 N13 S12 N13 M11 O13 N13 36 P14 P13 N11 M12 O13 N16 37 L9 L11 O13 P14 T21 38 O13 O21 39 G23 40 S14

Total 31 36 38 40 37 37 37 34 31 29

John Snow – Page 9 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

John Snow – Page 10 Grade 9 Applied Geography - Assignment #2 Fighting Cholera with Maps Rubric Student Name: Criteria Level Level Level Level Level 0 1 2 3 4 Knowledge / No information Limited use of information to Limited use of information to Good use of information to Understanding and use of maps Understanding provided solve the problems solve the problems. solve the problems effectively and correctly demonstrated Limited examination of Some examination of Effective examination of relationships on maps relationships on maps relationships Demonstrated skill in interpreting information Maps was incorrect Map was incomplete or Map was complete contained errors In-depth examination of relationships of maps and the information provided

Map very effectively and correctly conveyed information Communication No information Written work was presented with Written work was presented Written work was Written work was effectively and provided limited clarity and style with adequate clarity and completed with good clarity clearly presented with correct style style and style and logical organization of ideas Not all elements addressed Most elements were All elements addressed All elements highly and creatively addressed explored, and creatively presented Thinking / No information Solutions to problems not Solutions to problems Solutions to problems Solutions were accurate and highly Inquiry provided presented presented but with only some effectively presented effective, plus strong demonstrated effectiveness use of maps to solve problems Use of map to solve problems Use of map to solve and provide solutions was not Use of map to solve problems and provide Use of map to solve problems and effective problems and provide solutions was good provide solutions was very effective solutions was employed and presented a number of options to the user

Application No information Thoughts and ideas about Some original thoughts or Good and strong original Good and strong original thoughts provided geography and importance of ideas provided about the thoughts or ideas or ideas maps was limited importance of geography and maps to problem solving Good demonstration of Highly skilled demonstration of geographic skills to world geographic skills to world issues issues

John Snow – Page 11 Grade 9 Geography of Canada

Unit 2 Assignment #2 Fighting Cholera with Maps

Figure 1. Map showing the location of deaths from cholera in the Soho District of London

John Snow – Page 12 Grade 9 Geography of Canada

Unit 2 Assignment #2 Fighting Cholera with Maps

Figure 2. Map showing the location of deaths from cholera in Soho District of London and location of water pump sites

John Snow – Page 13