Cholera and the Water Supply in the South Districts of London in 1854

by John Snow

In table VI I have copied from the Weekly Returns of the Registrar-General the mortality from cholera in every subdistrict to which the supply of both, or either, of the water companies extends. I have also calculated the number of deaths which would have taken place in each subdistrict according to the number of persons supplied with water by each company respectively, and in accordance with the mortality ascertained for the whole of the population supplied; and it will be observed that the calculated mortality bears a very close relation to the real mortality in each subdistrict. This relation exists with regard both to the gross mortality and to the mortality to each 10,000 living, all through the table, and proves the overwhelming influence which the nature of the water supply exerted over the mortality, overbearing every other circumstance which could be expected to affect the progress of the epidemic. Thus, in the crowded, dirty, and very poor subdistricts of Lambeth Church, first part, and Waterloo, first part, lying by the river side, the mortality was low in consequence of the water supply being chiefly that of the Lambeth Company; whilst in the thinly peopled, and comparatively genteel subdistricts of Clapham and Battersea the mortality was very high, in consequence of the impure water of the Southwark and Vauxhall Company. Taking this inquiry altogether, and considering that the results which were published two years ago, and could only be estimated collectively, are now corroborated in detail through upwards of thirty subdistricts, it probably supplies a greater amount of statistical evidence than was ever brought to bear on a medical subject.

At the latter part of 1854, the General Board of Health procured from the two water companies, by order of the Secretary of State, a list of all the houses which they supplied, which lists are very valuable, as affording the means of ascertaining the exact water supply of each district and subdistrict separately. By direction of the Scientific Committee of the Board of Health, the lists have been employed in making a supplemental inquiry into the effect of the water supply on cholera. For this purpose they were compared with the lists of deaths at the General Registrar Office, and the results have been embodied in the recent Report of Mr. Simon, previously referred to. There are, however, certain circumstances, which were probably unknown to the Scientific Committee, and which render it impossible that an inquiry, conducted in this manner, could do more than approximate to the truth; and show why it can bear no comparison in point of accuracy to a personal inquiry, made on the spot, at the time of the epidemic. In the first place, throughout the greater part of Lambeth, Newington, and the Borough, the houses are either without numbers, or numbered very irregularly, and the numbers are liable to frequent change, as new houses are built, or older ones repainted; there are also frequently repetitions of the same number in the same street, and although, in some instances, the companies have returned the names of the occupiers, that can be of no assistance in the case of the poor, who occupy but one or two rooms, and form the greater bulk of the population. In the next place, the poor often furnish, unintentionally, a wrong number to the registrar, even when the houses are regularly numbered. They know their own homes perfectly, but, having no occasion to refer to the number, they partially forget it; and, in the greater number of my personal inquiries, I had to call at two or three houses before I found the one in which the death occurred. For these reasons it follows that, in comparing the lists of the water supply with the lists of deaths, many errors must have occurred; and as the deaths were six times as numerous in the houses supplied by the Southwark and Vauxhall Company as in those supplied by the Lambeth Company, the evident result would be that out of every six mistakes five would transfer a death from the former company to the latter, and only one would transfer a death from the latter company to the former. Another source of error, but operating to a less extent, is, that a number of persons who were attacked with cholera in houses supplied by the Southwark Company died in the workhouses of St. Saviour’s, Lambeth, and Newington, which were supplied by the Lambeth Company. It need excite no surprise, therefore, that the supplemental inquiry, embodied in the recent Report, instead of showing a mortality of 160 and 27 for the population supplied by the two water companies, or a difference of 6 to 1, showed a mortality of 125 and 37 per 10,000, or a difference of only 3½ to 1. It must be obvious, however, independently of the above facts, that a difference of three and a-half to one would not explain the great difference in the mortality of the various districts and subdistricts. The epidemic of 1853 is included with that of 1854 in Mr. Simon’s Report; but as there were but few deaths in 1853, and those chiefly amongst the population supplied by the Southwark Company, this circumstance would not much affect his results.

It is probable that, when the facts brought to light by this inquiry are sufficiently known, no one will deny the influence of impure water in promoting the mortality of cholera; but it must not be supposed that it is mere impurity of an ordinary kind that causes the disease, for there are innumerable facts to prove that ordinary impurities have no such effect, and that it is only when the specific morbid matter of the disease gains access to the water that cholera is propagated. Thousands of people drank water from their own neglected cisterns, during the late epidemic, as impure as that of the Southwark and Vauxhall Company, without ill effect. An inquiry made by the vestry of St. James’, Westminster,[^[8]] proved that the contents of a cesspool had been percolating for months through the three feet of earth which separated it from the pump well in Broad Street; but although hundreds of people were daily drinking the water, and cholera was extending fearfully in many parts of London, only a few scattered cases occurred in the streets near the pump till the end of August, when, a case having happened amongst the persons using the privy connected with the cesspool above mentioned, more than five hundred persons were attacked within two or three days.

In the cases in which the cholera poison gains access to a limited supply of drinking water, such as a tank or pumpwell, the outbreak it occasions is always sudden, violent, and limited; but when a river is the medium of the propagation of the disease, its progress is more gradual and extended, being diffused amongst the whole population using the water.

It is hardly necessary to remark, that every circumstance which proves the communication of cholera through the medium of water, corroborates the views, explained at the beginning of this paper, regarding its propagation in the crowded houses of the poor; for it cannot be supposed that a morbid matter, which can produce its specific effects after being diffused and distributed through a quantity of water, could fail to act in an undiluted state.

It was my intention to make some remarks on the drainage and water supply of towns, but this communication has already exceeded the limits which I prescribed for it.

Table I.
Shewing the results of the Author’s personal Inquiry in Twenty-One Sub-Districts.

Registration Districts.	Registration Sub-Districts.	Number of inhabited houses in 1851.	Population in 1851.	Estimated constant population per house.	“Number of houses, and estimated number of persons, supplied in 1854 with water as under.”				Water supply of the houses in which fatal attacks of cholera took place during first seven weeks of epidemic of 1854.					Deaths from cholera in first 7 weeks of epidemic of 1854.	Mortality per 10,000 supplied with water as under.
					By Southwark and Vauxhall Co.		By the Lambeth Company.		Southwark and Vauxhall Co.	Lambeth Co.	Thames, canals, or ditches.	From pumpwells.	Supply not ascertained.		Southwark and Vauxhall Co.	Lambeth Co.
					No. of houses.	Estim. Population.	No. of houses.	Estim. Population.
St. Saviour, Southw.	1. Christchurch	1,887	16,022	8·5	343	2,915	1,557	13,234	11	13	0	0	1	25	37·7	9·9
St. George, Southw.	1. Kent Road	2,558	18,126	7·1	1,779	12,630	563	3,997	52	5	0	0	0	57	41·1	12·5
	2. Borough Road	2,069	15,862	7·7	1,176	8,937	878	6,672	61	7	0	0	3	71	68·2	10·4
	3. London Road	2,365	17,836	7·5	383	2,872	1,533	11,497	21	8	0	0	0	29	73·1	6·9
Newington	1. Trinity	3,224	20,922	6·5	1,661	10,132	1,372	8,370	52	6	0	0	0	58	51·3	7·1
	2. St. Peter, Walworth	4,925	29,861	6·1	2,340	14,274	1,758	10,724	84	4	0	0	2	90	58·8	3·7
	3. St. Mary	2,309	14,033	6·1	489	2,983	899	5,484	19	1	0	1	0	21	64·5	1·8
Lambeth	1. Waterloo, part 1	1,729	14,088	8·1	438	3,548	1,474	11,939	9	1	0	0	0	10	25·6	0·8
	2. Waterloo, part 2	2,191	18,348	8·4	864	7,171	1,510	12,533	25	8	2	1	0	36	34·8	6·3
	3. Lambeth church, pt. 1	2,451	18,409	7·5	415	3,113	2,117	15,878	6	9	1	0	2	18	19·2	5·6
	4. Lambeth church, pt. 2	3,849	26,784	7·0	1,124	7,868	2,289	16,023	34	13	0	1	5	53	42·9	8·1
	5. Kennington, part 1	3,977	24,261	6·1	2,586	15,775	444	2,708	63	5	0	3	0	71	39·9	18·4
	6. Kennington, part 2	3,288	18,848	5·7	1,206	7,874	986	5,620	34	3	0	1	0	38	43·2	5·7
	7. Brixton	2,362	14,610	6·1	310	1,922	1,509	9,356	5	2	0	0	2	9	26·0	2·1
	8. Norwood	600	3,977	6·6	0	0	160	1,066	0	2	5	1	0	8		18·7
Wandsworth	3. Wandsworth	1,522	9,611	6·3	144	907	15	94	1	0	8	2	0	11	11·0
	4. Putney	918	5,280	5·7	13	74	0	0	0	0	0	1	0	1
	5. Streatham	1,419	9,023	6·4	0	0	515	3,244	0	1	0	5	0	6		3·0
Camberwell	1. Dulwich	259	1,632	6·3	0	0	4	25	0	0	0	0	0	0
	4. St. George	2,845	15,849	5·6	767	4,295	971	5,437	30	9	0	2	1	42	69·8	16·5
Lewisham	5. Sydenham	801	4,501	5·6	0	0	unkno.	unkno.	0	1	0	2	1	4
Totals		47,548	317,883	6·6	16,038	107,290	20,554	143,901	507	98	16	20	17	658	47·2	6·8

Table II.
Shewing the results of the Inquiry made by Mr. Whiting in Eleven Sub-Districts.

Registration Districts.	Registration Sub-Districts.	Number of inhabited houses in 1851.	Population in 1851.	Estimated constant population per house.	“Number of houses, and estimated number of persons, supplied in 1854 with water as under.”				Water supply of the houses in which fatal attacks of cholera took place during first seven weeks of epidemic of 1854.					Deaths from cholera in first 7 weeks of epidemic of 1854.	Mortality per 10,000 supplied with water as under.
					By Southwark and Vauxhall Co.		By the Lambeth Company.		Southwark and Vauxhall Co.	Lambeth Co.	Thames, canals, or ditches.	From pumpwells.	Supply not ascertained.		Southwark and Vauxhall Co.	Lambeth Co.
					No. of houses.	Estim. Population.	No. of houses.	Estim. Population.
St. Saviour, Southw.	2. St. Saviour	2,713	10,709	7·3	2,238	16,337	123	898	115	0	10	0	0	125	70·3
St. Olave, Southwark	1. St. Olave	880	8,015	9·1	961	8,745	0	0	43	0	5	0	5	53	49·1
	2. St. John, Horselydown	1,480	11,360	7·7	1,170	9,360	0	0	48	0	3	0	0	51	50·1
Bermondsey	1. St. James	2,863	18,899	6·6	3,511	23,173	105	693	102	0	21	0	0	123	44·0
	2. St. Mary Magdalen	1,865	13,934	7·5	2,301	17,258	0	0	83	0	4	0	0	87	48·0
	3. Leather Market	2,279	15,295	6·7	2,090	14,003	163	1,092	81	0	0	0	0	81	57·8
Wandsworth	1. Clapham	2,657	16,290	6·1	1,106	6,747	22	134	19	0	0	5	0	24	28·1
	2. Battersea	1,760	10,560	6·0	1,046	6,276	46	270	42	0	8	4	0	54	66·9
Camberwell	2. Camberwell	2,851	17,742	6·2	1,474	9,139	103	639	96	0	0	0	0	96	104·8
	3. Peckham	3,457	19,444	5·6	971	5,438	70	392	59	0	0	0	0	59	108·4
Rotherhithe	Rotherhithe	2,792	17,805	6·4	1,909	12,218	0	0	68	0	35	0	0	103	55·6
Totals		25,597	169,053	6·5	18,777	128,694	632	4,124	756	0	86	9	5	856	58·7
Totals of Table I.		47,548	317,883	6·6	16,038	107,290	20,554	143,901	507	98	16	20	17	658	47·2	6·8
Houses in streets where no death occurred				6·4	4,500	28,929	3,643	23,338	0	0	0	0	0	0
Not identified				6·6	411	2,712	25	165
Totals of thirty-two Sub-districts		73,145	480,936	6·0	39,726	267,625	24,854	171,528	1263	98	102	29	22	1514	47·2	5·7