London Sewage Company : report upon the various plans proposed for rendering available the manure contained in the sewage water of the metropolis ... / by Thomas Wicksteed.

Date:
1845
Catalogue details

Licence: Public Domain Mark

Credit: London Sewage Company : report upon the various plans proposed for rendering available the manure contained in the sewage water of the metropolis ... / by Thomas Wicksteed. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    current into the river, necessarily and naturally rises through any openings it can find, and a stream of noxious effluvia is evolved. A further disadvantage resulting from this penning up of the sewage, is, that the current through the sewers being checked, the water becomes quiescent, and the heavy particles previously held in mechani- cal suspension are deposited, and accumulate. When the current in the sewers re-commences, it is slow, depending upon the rate at which the tide falls in the river. Until it has fallen below the level of the pent-up sewage, there is no fall in the sewer. Then as the tide falls inch by inch, so does the fall in the sewer increase, but not in the same ratio, because the water being always running, the relative differ- ence between the two levels is always diminishing. The case would be different were the sewer water held back by mechanical means, until there was a sufficient fall of tide in the river; but it is not so— the process is gradual, and no fall is obtained suffi- cient to scour away the accumulated deposits. Hence the necessity of manual labour to clear away these offensive deposits, which must be brought to the surface, or for machinery for carrying it off by flushing, and the demand for larger supplies of water, which would be useless unless there was an uninterrupted current in the sewers. Hence also arises the necessity for prohibiting the discharge of the street sweepings into the sewers, as they would add to the deposit already referred to, a further quantity of heavier matter.