Sewage-analysis. A practical treatise on the examination of sewage and effluents from sewage... Including also a chapter on utilisation and purification / by J. Alfred Wanklyn and William John Cooper.

  • Wanklyn, J. Alfred (James Alfred), 1834-1906.
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: Sewage-analysis. A practical treatise on the examination of sewage and effluents from sewage... Including also a chapter on utilisation and purification / by J. Alfred Wanklyn and William John Cooper. Source: Wellcome Collection.

Provider: This material has been provided by London School of Hygiene & Tropical Medicine Library & Archives Service. The original may be consulted at London School of Hygiene & Tropical Medicine Library & Archives Service.

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    Obviously, therefore, inasmuch as there was less oxygen than atmospheric air contains, the evolution of gas in our experiment was not evolution of oxygen but of nitrogen. The space in the digestion tube unoccupied by liquid was measured, and equalled 38.1 c. c. We are thus provided with data for determining whether the permanganate had evolved oxygen, and also how much nitrogen came from the urea. c. c. Volume of gas left in the tube . . . 38.1 Volume of gas escaped from the tvihe . . 15 7 Total volume of gas after experiment . • 53-8 consisting of 8.34 c. c. of oxygen and 45-46 c. c. of nitrogen. Now the 38.1 c. c. of air originally present in the tube when it was sealed up contained 8.00 c. c. of oxygen and 30.1 c. c. of nitrogen. We have therefore :— Oxygen present originally .... 8.00 Oxygen found after experiment . . • 8.34 No oxygen, or only a trace of oxygen, was set free from the permanganate; also the urea had evolved about 15 c. c. of nitrogen gas. This amount of nitrogen is not half that which the urea contained (o.ioo gramme of urea contains 37.2 c. c. of nitrogen gas at 0° C. and 760 mm. pressure). A little of the nitrogen is accounted for as ammonia, for .0032 gramme of nitrogen was found in the tube after the experiment m the form of ammonia, which was distilled off and estimated by titration. Thus there remains about half of the total nitrogen to be accounted for, which must have been con-