Analysis of evidence laid before the Health of Towns Commission and the Select Committee of the House of Commons on Metropolitan sewage manure; together with extracts ... shewing the value of the refuse of towns, and the advantages in a sanatory point of view of its application in a liquid form to agricultural purposes.

  • Health of Towns Association (London, England)
Date:
1847
Catalogue details

Licence: Public Domain Mark

Credit: Analysis of evidence laid before the Health of Towns Commission and the Select Committee of the House of Commons on Metropolitan sewage manure; together with extracts ... shewing the value of the refuse of towns, and the advantages in a sanatory point of view of its application in a liquid form to agricultural purposes. Source: Wellcome Collection.

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    which they must gradually exhaust. Now, amongst these substances, we find three which are especially valuable to plants; of these three, the most important is ammonia; ammoniacal salts exist in these waters to a considerable :rCi7u ’a The quantity of potash,phos¬ phates,and am¬ monia, daily passing into the Thames from the King’s Scholars’ Pond Sewer: Potash 1 ton, phos¬ phates 1 ton, ammonia 1 or 2 tons. extent:—and in addition to these, we have alkaline salts, potash, and common salt; potash is not so abundant as common salt:—and in the third place, earthy phosphates, containing the whole phosphoric acid. I mention these three compounds in particular, because they are substances that are found in the soil in but small quantities, and yet are absolutely essential to the maintenance of vegetable life. The quantity of potass which passes out of this sewer per day (estimating the average discharge of the sewer at about thirty gallons in a second, so that the aver¬ age daily discharge would be about two millions and a half of gallons), the average quantity of potass would be about a ton weight, and about the same quantity of phosphates of the earths pass off every day; i. e., about a ton of phos¬ phoric acid, in combination with lime and magnesia, emp¬ tied from this sewer every day in waste. Of ammonia there is more than that, nearly double that quantity, nearly two tons of ammonia. The two analyses differ in some respects; the ammonia varies. In one case I find about a ton, and in the other about two tons per diem. In the case where the water was stopped by flood-gates, which I consider the fairest average of the two, I find as much as two tons turned but into the Thames per day; the quantity will vary according to the season.”—Evidence of Professor Miller, of King's College, Report of Select Committee on Metropolitan Sewage Manure, p, 38. Matters in so¬ lution and sus¬ pension in the water of the King’s Schol¬ ars’ Pond Sewer. An analysis of one average specimen of Sewer Water, by Dr. Miller, gave the following results:— Matters in solution, per gallon, 45 grains, 9 tenths. Matters in suspension, ditto, 44J grains. A second average specimen, examined by Dr. Miller, gave a larger proportion of both constituents. A specimen of Sewer Water collected at four different times of the day, from the King’s Scholars’ Pond Sewer, analyzed in the laboratory of King’s College, gave the following results:— Matters in solution, per gallon, 80 grains. Matters in suspension ditto 1000 grains.