On the mode of communication of cholera

by John Snow

THE CHOLERA OF 1849 COMPARED WITH THAT OF 1854.

The table exhibits an increase of mortality in 1854 as compared with 1849, in the sub-districts supplied by the Southwark and Vauxhall Company only, whilst there is a considerable diminution of mortality in the sub-districts partly supplied by the Lambeth Company. In certain sub-districts, where I know that the supply of the Lambeth Water Company is more general than elsewhere, as Christchurch, London Road, Waterloo Road 1st, and Lambeth Church 1st, the decrease of mortality in 1854 as compared with 1849 is greatest, as might be expected. Waterloo Road 1st, which suffered but little from cholera in the present year, is chiefly composed of very dirty narrow streets, in the neighbourhood of Cornwall Road and the New Cut, inhabited by very poor people; and Lambeth Church 1st, which suffered still less, contains a number of skinyards and other factories, between Lambeth Palace and Vauxhall Bridge, which have often been inveighed against as promoting the cholera. The high mortality of the Streatham district in 1849 was caused by the outbreak of cholera in Drouett’s Asylum for pauper children, previously mentioned.

Whilst making inquiries in the south districts of London, I learned some circumstances with respect to the workhouses which deserve to be noticed. In Newington Workhouse, containing 650 inmates, and supplied with the water from Thames Ditton, there had been but two deaths from cholera amongst the inmates down to 21st September, when the epidemic had already greatly declined. In Lambeth Workhouse, containing, if I remember rightly, nearly 1,000 inmates, and supplied with the same water, there had been but one death amongst the inmates when I was there in the first week of September. In St. Saviour’s workhouse, which is situated in the parish of Christchurch, and is supplied with water by the Lambeth Company, no inmate died of cholera before I called in the first week of September. On the other hand, in the workhouse of St. George, Southwark, supplied with the water of the Southwark and Vauxhall Company, six inmates died out of about 600 before the 26th August, when the epidemic had only run one-third of its course. The mortality was also high amongst the inmates of St. Olave’s Workhouse, supplied with water by the Southwark and Vauxhall Company, but I do not know the number who died. I trust, however, that the Registrar

HORSEMONGER LANE GAOL.

General, in giving an account of the recent epidemic, will make a return of the deaths amongst the inmates of the various workhouses and other institutions on the south side of the Thames, together with the water supply of the buildings. Bethlehem Hospital, the Queen’s Prison, Horsemonger Lane Gaol, and some other institutions, having deep wells on the premises, scarcely suffered at all from cholera in 1849, and there was no death in any of them during the part of the recent epidemic to which my inquiry extended.

DISTRICT OF CHELSEA WATER COMPANY.

On the north side of the Thames the mortality during the recent epidemic seems to have been influenced more by the relative crowding and want of cleanly habits of the people, and by the accidental contamination of the pump-wells, than by the supply of the water companies. The water of the New River Company could have no share in the propagation of cholera, as I explained when treating of the epidemic of 1849; and the extensive districts supplied by this company have been very slightly visited by the disease, except in certain spots which were influenced by the causes above mentioned. The water of the East London Company is also free from the contents of sewers, unless it be those from the neighbourhood of Upper Clapton, where there has been very little cholera. The districts supplied by this company have been lightly visited, except such as lie near the Thames, and are inhabited by mariners, coal and ballast-heavers, and others, who are employed on the river. Even Bethnal Green and Spitalfields, so notorious for their poverty and squalor, have suffered a mortality much below the average of the metropolis. The Grand Junction Company obtain their supply at Brentford, within the reach of the tide and near a large population, but they detain the water in large reservoirs, and their officers tell me they filter it; at all events, they supply it in as pure a state as that of the Lambeth Company obtained at Thames Ditton, and their districts have suffered very little from cholera except at the spot where the irruption occurred from the contamination of the pump-well in Broad Street, Golden Square. The West Middlesex Company, obtaining their supply from the Thames at Hammersmith, have also very large reservoirs, and the districts they supply have suffered but little from cholera, except the Kensington brick fields, Starch Green, and certain other spots, crowded with poor people, chiefly Irish.

CHOLERA IN THE DISTRICT OF THE CHELSEA WATER COMPANY.

The districts supplied by the Chelsea Company have suffered a much greater mortality, during the recent epidemic, than the average of the whole metropolis, as the subjoined table (No. XIII) shows. But the mortality in these districts is only half as great as in the houses supplied by the Southwark and Vauxhall Company, who obtain their supply from the Thames just opposite the spot where the Chelsea Company obtain theirs. The latter company, however, by detaining the water in their reservoirs, and by filtering it, are enabled to distribute it in a state of comparative purity; but I had ample opportunities of observing, in August and September last, that this was far from being the state of the water supplied by the Southwark and Vauxhall Company. Many of the people receiving this latter supply were in the habit of tying a piece of linen or some other fabric over the tap by which the water entered the butt or cistern, and in two hours, as the water came in, about a tablespoon of dirt was collected, all in motion with a variety of water insects, whilst the strained water was far from being clear. The contents of the strainer were shown to me in scores of instances. I do not, of course, attribute the cholera either to the insects or the visible dirt; but it is extremely probable that the measures adopted by the Chelsea Company to free the water from these repulsive ingredients, either separated or caused the destruction of the morbid matter of cholera. It is very likely that the detention of the water in the company’s reservoirs permitted the decomposition of the cholera poison, and was more beneficial than the filtering, for the following reasons. The water used in Millbank Prison, obtained from the Thames at Millbank, was filtered through sand and charcoal till it looked as clear as that of the Chelsea Company; yet, in every epidemic, the inmates of this prison suffered much more from cholera than the inhabitants of the neighbouring streets and those of Tothill Fields Prison, supplied by that company.[^[18]] In the early part of August last, the use of the Thames water was entirely discontinued in Millbank Prison, and water from the Artesian well in Trafalgar Square was used instead, on the recommendation of Dr. Baly, the physician to the prison. In three or four days after this change, the cholera, which was prevailing to an alarming extent, entirely ceased.

TABLE XIII.