The rise & progress of aerobic methods of sewage disposal : being notes of a lecture delivered before the Association of Managers of Sewage Disposal Works at the Royal Sanitary Institute on March 18th, 1911 / by W.J. Dibdin.

  • Dibdin, W. J. (William Joseph), 1850-1925.
Date:
1911
Catalogue details

Licence: In copyright

Credit: The rise & progress of aerobic methods of sewage disposal : being notes of a lecture delivered before the Association of Managers of Sewage Disposal Works at the Royal Sanitary Institute on March 18th, 1911 / by W.J. Dibdin. 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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    from the beds treating the sewage of Devizes. Cultures on o o nutrient gelatine gave the following results:— Table VI. — Deposit on top of slates 18in. below surface. Deposit on under surface of slates 18in. below surface. Moisture in mud, per cent. ... 75-3 657 Colonies developed on nutrient gelatine per gram of wet mud 3,044,000.000 3,167,000,000 With the view of obtaining a further insight into the question, I collected two series of samples of the deposit on the slate biological beds—one from those at Devizes, after they had been at work for fourteen months, and another from those at High Wycombe, after about nine months’ work. These two series are of special interest, as those from Devizes are from sewage of an exceptionally foul character, whilst that of High Wycombe is probably one of the weakest in England, and the two series may be taken as fairly representing the extremes in this respect. It must not be overlooked, how- ever, that sewage debris is of about the same general character whether the volume of water is more or less, the strength of the sewage affecting the character of the effluent to a greater extent than that of the deposit. In each series three samples were collected in such a manner as to follow the variations which had taken place with the increasing age of the deposit, viz.:—Sample No. 1 was care- fully scraped from the surface of the deposit, and may be taken as representing the most recently deposited debris, with its adhering bacterial gelatinous film, &c.; sample No. 2 was collected as nearly as possible at about half-depth ; and sample No. 3 was taken from the under portion next to the slates. It was noticed that in each case large numbers of minute worms, monadina, anguillulte, and other organisms were present, the worms especially indicating the aerobic conditions