The organic analysis of potable waters / by J. A. Blair.

  • Blair, J. A. (James Andrew)
Date:
1890
Catalogue details

Licence: Public Domain Mark

Credit: The organic analysis of potable waters / by J. A. Blair. Source: Wellcome Collection.

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

    18/136 (page 6)
    processes^ to some extent^ measure the potentiality of the organic matter for rapid chemical changes. Both methods take advantage of the fact that organic matter, in the presence of suitable oxidising agents, readily takes up oxygen, and becomes partially oxidised into less complex, but more chemically stable, compounds. In the oxygen process, the quantity of oxygen used up in this way is made the indicator for judging of the organic impurity of the sample of water; but in Mr Wanklyn’s process, the ammonia evolved by the combined action of caustic alkali and an oxidising agent is the indicator of the amount of organic impurity. It is claimed for both processes that the results obtained are sufficiently uniform to enable the analyst to form an opinion of the fitness, or unfitness of the water for potable purposes. The Albuminoid Ammonia Process may be carried out in the following way. Certain solutions are required, and instructions for their preparation will be found in Appendix A. The solutions are— (1) A dilute solution of ammonium chloride of the strength that each c.c. contains milligramme of ammonia. (2) Nessler’s reagent. (3) A strongly alkaline solution of permanganate of potash. (4) A saturated solution of sodium carbonate.