MONDAY, AUGUST 28: Five-month-old Frances (Fanny) Lewis, daughter of Sarah and Thomas Lewis of 40 Broad Street, falls ill with diarrhea and vomiting.
THURSDAY, AUGUST 31: “Mr. G.,” a tailor who also lives at 40 Broad Street, along with nineteen or twenty other people, falls ill. Twenty-nine-year-old Henry Whitehead, assistant curate at St. Luke’s Church, is called out to several homes where people have been struck.
FRIDAY, SEPTEMBER 1: Mr. G. dies of cholera. A yellow flag is placed on Berwick Street as a warning, and carts begin removing bodies.
SATURDAY, SEPTEMBER 2: Baby Frances Lewis dies on Broad Street. Several miles away in Hampstead, Susannah Eley, a fifty-nine-year-old widow who has been drinking Broad Street water delivered by her sons, dies after a sixteen-hour illness. At Middlesex Hospital, the nurse Florence Nightingale begins seeing patients brought in every half hour from Broad Street and elsewhere in the Soho district.
SUNDAY, SEPTEMBER 3: Dr. John Snow, who lives a half mile away on Sackville Street, hears about the cholera epidemic. He goes to inspect the popular Broad Street pump and takes water samples for inspection.
MONDAY, SEPTEMBER 4: Mrs. G., the widow of the tailor, falls ill with cholera. Dr. Snow returns to Broad Street and begins asking questions of the residents.
TUESDAY, SEPTEMBER 5: Mrs. G. dies in the morning. Dr. Snow goes to the General Register Office in Somerset House to ask William Farr for records of recent deaths.
THURSDAY, SEPTEMBER 7: Dr. Snow appears before an emergency committee of the board of governors of St. James Parish and convinces them to remove the handle of the Broad Street pump.
FRIDAY, SEPTEMBER 8: The pump handle is removed. Thomas Lewis, father of Frances Lewis, develops symptoms of cholera.
TUESDAY, SEPTEMBER 19: Thomas Lewis dies.
THURSDAY, NOVEMBER 23: St. James Parish forms an inquiry committee to look further into the cholera epidemic, which killed 616 people. Dr. Snow and Rev. Whitehead are invited to join.
MONDAY, NOVEMBER 27: An inspection of the Broad Street well is conducted, but no holes are found.
MONDAY, DECEMBER 4: Dr. Snow presents his cholera map at a meeting of the Epidemiological Society of London.
TUESDAY, DECEMBER 19: The Gazzetta Medica Italiana contains an article by researcher Filippo Pacini, who reports microscopic findings from postmortem exams of cholera patients. His research will not become widely known until after his death.
SATURDAY, JANUARY 27: The London publisher J. Churchill releases an expanded version of On the Mode of Communication of Cholera, a monograph by Dr. John Snow. Dr. Snow gives a copy to Rev. Whitehead, who is continuing to conduct interviews with Broad Street residents for his own report.
TUESDAY, MARCH 27: While investigating death records in the General Register Office, Rev. Whitehead is drawn to the following entry: “At 40, Broad Street, 2nd September, a daughter, aged five months, exhaustion, after an attack of Diarrhoea four days previous to death.” Rev. Whitehead finds that Mrs. Lewis emptied diapers into the cesspool, and he suspects this may be the index case and the cause of the well’s contamination.
MONDAY, APRIL 23: A surveyor, Jehoshaphat York, excavates the cesspool at 40 Broad Street and the surrounding area.
TUESDAY, MAY 1: York presents his report, showing that sewage was backing up in a drain and the cesspool’s bricks were decaying. Sewage from the cesspool had been seeping into the Broad Street well, less than three feet away.
WEDNESDAY, JULY 25: The St. James Cholera Inquiry Committee completes its work, which includes reports from York, Dr. Snow, and Rev. Whitehead. The committee concludes that the cholera outbreak “was in some manner attributable to the use of the impure water of the well in Broad Street.”
WEDNESDAY, SEPTEMBER 26: Based on a petition from residents, a decision is made to reopen the Broad Street pump.