BRIEF HISTORY DURING THE SNOW ERA (1813-58)

In writing of the Broad Street Pump cholera outbreak of 1854, John Snow cited six episodes with addresses that involve the Broad Street pump.  He was attempting to use all available information to support his hypothesis that contaminated well water caused the outbreak.  Snow's text from his 1855 book is followed with a detailed map of the area showing the exact location of the episode or event.  The general area of the Broad Street pump outbreak is shown in cells K13 and K14 of Reynolds' 1859 map, but is better seen in sections of the Old Ordnance Survey map of 1870.  The latter is used to describe the exact locations. 

Broad Street in the 1859 map appears at the bottom right of cell K13 as Broa and in the middle left of cell K14 as d. 

Why were most residents of the St. James Workhouse spared from infection?

The Workhouse in Poland Street is more than three-fourths surrounded by houses in which deaths from cholera occurred, yet out of five hundred and thirty-five inmates only five died of cholera, the other deaths which took place being those of persons admitted after they were attacked. The workhouse has a pump-well on the premises, in addition to the supply from the Grand Junction Water Works, and the inmates never sent to Broad Street for water. If the mortality in the workhouse had been equal to that in the streets immediately surrounding it on three sides, upwards of one hundred persons would have died.

- Snow J. On the Mode of Communication of Cholera, 1855, page 42.

Why were there no cases at the Lion Brewer? 

There is a Brewery in Broad Street, near to the pump, and on perceiving that no brewer's men were registered as having died of cholera, I called on Mr. Huggins, the proprietor. He informed me that there were above seventy workmen employed in the brewery, and that none of them had suffered from cholera, -- at least in a severe form, -- only two having been indisposed, and that not seriously, at the time the disease prevailed. The men are allowed a certain quantity of malt liquor, and Mr. Huggins believes they do not drink water at all; and he is quite certain that the workmen never obtained water from the pump in the street. There is a deep well in the brewery, in addition to the New River water. 

- Snow J. On the Mode of Communication of Cholera, 1855, page 42.

Many of those who drank pump water brought to a nearby percussion-cap factory became cases.

At the percussion-cap manufactory, 37 Broad Street, where, I understand, about two hundred workpeople were employed, two tubs were kept on the premises always supplied with water from the pump in the street, for those to drink who wished; and eighteen of these work people died of cholera at their own homes, sixteen men and two women.

- Snow J. On the Mode of Communication of Cholera, 1855, page 43.

Some at the neighborhood manufactory of dentists' material became cases and others didn't. Why? 

Mr. Marshall, surgeon, of Greek Street, was kind enough to inquire respecting seven workmen who had been employed in the manufactory of dentists' materials, at Nos. 8 and 9 Broad Street, and who died at their own homes. He learned that they were all in the habit of drinking water from the pump, generally drinking about half-a-pint once or twice a day; while two persons who reside constantly on the premises, but do not drink the pump-water, only had diarrhea. 

- Snow J. On the Mode of Communication of Cholera, 1855, page 43.

If the disease was caused by a living organism, what was the incubation period?

I am indebted to Mr. Marshall for the following cases, which are interesting as showing the period of incubation, which in these three cases was from thirty-six to forty-eight hours. Mrs. -----, of 13 Bentinck Street, Berwick Street, aged 28, in the eighth month of pregnancy, went herself (although they were not usually water drinkers), on Sunday, 3rd September, to Broad Street pump for water. The family removed to Gravesend on the following day; and she was attacked with cholera on Tuesday morning at seven o'clock, and died of consecutive fever on 15th September, having been delivered. Two of her children drank also of the water, and were attacked on the same day as the mother, but recovered.

- Snow J. On the Mode of Communication of Cholera, 1855, page 43.

Another case provides more information on the length of the incubation period and natural history of the disease.  

Dr. Fraser, of Oakley Square, kindly informed me of the following circumstance. A gentleman in delicate health was sent for from Brighton to see his brother at 6 Poland Street, who was attacked with cholera and died in twelve hours, on 1st September. The gentleman arrived after his brother's death, and did not see the body. He only stayed about twenty minutes in the house, where he took a hasty and scanty luncheon of rumpsteak, taking with it a small tumbler of brandy and water, the water being from Broad Street pump. He went to Pentonville, and was attacked with cholera on the evening of the following day, 2nd September, and died the next evening.

- Snow J. On the Mode of Communication of Cholera, 1855, page 44.

For more of John Snow's thoughts and observations, as written in his 1855 book, click here.