§ Lieut-Colonel POWNALLasked the Minister of Health whether his attention has been drawn to the discovery by Mr. Thomas H. Fairbrother, M.Sc., and Dr. Arnold Renshaw, of Manchester, of several dyes which in the activated sludge process of sewage purification can kill the devouring protozoa without harming the purifying bacteria; and whether he will give facilities for carrying out on a large scale the results of this highly important piece of laboratory research work?
§ Sir A. MONDMy attention has been drawn to the experiments referred to. I am, however, advised that further research work will be needed in order to test the application of this and other discoveries to the activated sludge process of sewage purification, and I am making inquiries as to the best means of facilitating the necessary investigations.