The water question : a letter, addressed (by permission) to the Rt. Hon. the Earl of Derby, K.G., explaining a proposal for the supply of the metropolis from the higher sources of the Thames in conjunction with the storage of surplus waters / by J. Bailey Denton.

  • John Bailey Denton
Date:
1866
Catalogue details

Licence: Public Domain Mark

Credit: The water question : a letter, addressed (by permission) to the Rt. Hon. the Earl of Derby, K.G., explaining a proposal for the supply of the metropolis from the higher sources of the Thames in conjunction with the storage of surplus waters / by J. Bailey Denton. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    source of Wcater contamination tlian the direct admixture of cholera excreta. It is constantly assumed, but it has never yet heen proved^ that the rice water evacuations contain the germs of cholera, and although this assumption is not improbable, it will not serve to explain many facts in the history of cholera. It offers no solution of a circumstance frequently noticed, namely, the sudden and mysterious outbreak of the disease in a district in which not a single case of cholera has previously oc- curred; and it is scarcely consistent with the occasional rapid disappearance of the disease from districts in which it has already raged, since the water, if tainted by excreta at the commencement of tlie attack, must be a hundred-fold more so during the preva- lence of the epidemic. But if it be admitted that the cholera germ exists in the atmosphere, and is absorbed, as it surely would be by the water, this difficulty is at once removed, as it is simply in accordance with experience to suppose that the germs of the disease, when freshly developed, would prove more energetic in their action than they would towards the close of the epidemic, and therefore that water which at first might prove poisonous, would ultimately lose its poisonous character. I would guard myself, however, from being understood to imply that the occurrence of cholera is due exclusively or even prin- cipally to impure water. There are endless facts which prove that the atmosphere is the principal vehicle for tlie diffusion of the cholera poison, which may also be conveyed by con- tagion, or direct transmission from one person to another. But I believe that water drawn from a tainted source, or in other words, from a district in wliicli cholera prevails, may become contaminated by the cholera poison, derived probably in part fi-om choleraic excreta and in part from contact witli the tainted atrnosphere. When so contaminated, the water doubtless exercises an important influence on the spread of the disorder. As the germs of cholera have never been isolated (for the so-called cholrine mentioned in the Registrar-General's report cannot be so regarded until its power to produce cholera has been proved), it is impossible to say what means may be requisite to ensure its removal from water which has once con- tained it. Direct experiment has shown that mere filtration, even through animal charcoal, fails to remove more than a portion of the organic constituents of water, and that there are certain organisms Avhich appear even to resist the influence of boiling. The effect of running water in oxidising or otherwise destroying organic matter is very remarkable, but there are no reliable data on which to base an opinion as to the length of run