The death of Mrs. E. and her niece, who drank the water from Broad Street at the West End, Hampstead, deserves especially to be noticed. I was informed by Mrs. E.'s son that his mother had not been in the neighborhood of Broad Street for many months. A cart went from Broad Street to West End every day, and it was the custom to take out a large bottle of the water from the pump in Broad Street, as she preferred it. The water was taken out on Thursday, the 31st of August, and she drank of it in the evening and also on Friday. She was seized with cholera on the evening of the latter day, and died on Saturday. A niece who was on a visit to this lady also drank of the water. She returned to her residence, a high and healthy part of Islington, was attacked with cholera, and died also. There was no cholera at this time either at West End or in the neighborhood where the niece died. Besides these two persons only one servant partook of the water at West End, Hampstead, and she did not suffer, at least not severely. She had diarrhœa."
Dr. Snow's inquiry into the cases of cholera which were nearer other pumps showed that in most the victims had preferred, or had access to, the water of the Broad Street well, and in only a few cases was it impossible to trace any connection with the pump. Finally, Dr. Snow made a statistical statement of great value which is here given in its original form:
The Broad Street, London, Well and Deaths from Asiatic Cholera near it in 1854
In addition to the original and general inquiry conducted from the time of the outbreak by Dr. Snow, the Rev. H. Whitehead, M. A., curate of St. Luke's in Berwick Street, and like Dr. Snow, a member of the Cholera Inquiry Committee, whose knowledge of the district both before and during the epidemic, owing to his official position, gave him unusual advantages, made a most elaborate and painstaking house-to-house investigation of one of the principal streets affected, viz., Broad Street itself.
The Rev. H. Whitehead's report, like that of Dr. Snow, is a model of careful and extended observation and study, cautious generalizing and rigid verification. It is an excellent instance of inductive scientific inquiry by a layman in sanitation. Mr. Whitehead found the number of houses on Broad Street 49; the resident householders 35; the total number of resident inhabitants 896; the total number of deaths among these 90. Deaths among non-residents (workmen, etc.) belonging to the street, 28. Total deaths chargeable to this street alone, 118. Only 10 houses out of 49 were free from cholera.
The dates of attack of the fatal cases resident in this single street were as follows:
The Broad Street, London, Well and Deaths from Asiatic Cholera near it in 1854
| Date of Attack | Number of Fatal Attacks | |
| August | 12 | 1 |
| August | 28 | 1 |
| August | 30 | 1 |
| August | 31 | 6 |
| September | 1 | 26 |
| September | 2 | 24 |
| September | 3 | 9 |
| September | 4 | 8 |
| September | 5 | 6 |
| September | 6 | 5 |
| September | 7 | 0 |
| September | 8 | 2 |
| September | 9 | 1 |
| 90 | ||
Mr. Whitehead's detailed investigation was not made until the spring of 1855, but in spite of this fact it supplied most interesting and important confirmatory evidence of Dr. Snow's theory that the Broad Street well was the source of the epidemic. Mr. Whitehead, moreover, went further than Dr. Snow, and endeavored to find out how the well came to be infected, why its infectious condition was so limited, as it appeared to have been, and to answer various other questions which occurred in the course of his inquiry. As a result, he concluded that the well must have been most infected on August 31st, that for some reason unknown a partial purification began on September 2d, and thereafter proceeded rapidly. There was some evidence that on August 30th the water was much less infected than on the 31st, so that its dangerous condition was apparently temporary only. He further discovered that in the house No. 40 Broad Street, which was the nearest house to the well, there had been not only four fatal cases of cholera contemporaneous with the epidemic, but certain earlier cases of an obscure nature, which might have been cholera, and that dejecta from these had been thrown without disinfection into a cesspool very near the well. On his reporting these facts in April, 1855, to the main committee, Mr. J. York, secretary and surveyor to the committee, was instructed to survey the locality and examine the well, cesspool and drains at No. 40 Broad Street. Mr. York's report revealed a startling condition of affairs. The well was circular in section, 28 feet 10 inches deep, 6 feet in diameter, lined with brick, and when examined contained 7 feet 6 inches of water. It was arched in at the top, dome fashion, and tightly closed at a level 3 feet 6 inches below the street by a cover occupying the crest of the dome. The bottom of the main drain of the house No. 40 Broad Street, lay 9 feet 2 inches above the water level, and one of its sides was distant from the brick lining of the well only 2 feet 8 inches. It was constructed on the old fashioned plan of a flat bottom, 12 inches wide, with brick sides rising about 12 inches high, and covered with old stones. As this drain had but a small fall or inclination outward to the main sewer, the bottom was covered with an accumulation of soil deposit about 2 inches thick, and upon clearing this soil away the mortar joints of the old stone bottom were found to be perished, as was also all the jointing of the brick sides, which had brought the brickwork into the condition of a sieve, and through which the house drainage water must have percolated for a considerable period.