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bacilli are found in the waste matter from the bodies of patients, and 

 may, and must, if the greatest care be not taken to make the thing im- 

 possible, tlnd their way into the atmosjjhere, and into open water 

 courses, into wells by surface or sewer drainage if such drainage finds 

 access to them. And while the taking of these disease germs into the 

 lungs in respiration is unquestionably the most effective way of spread- 

 ing the disease yet experience has proved beyond a doubt that taking 

 them into the system in our drinking water or our food is only second 

 in danger. J might quote many historical instances in proof of this if 

 time permitted, You will find such in the Sixth Report of the Royal 

 Commissioners (1868) on preventing the pollution of rivers. The im- 

 portance of immediate attention to the destruction of the dejecta of 

 patients suffering from any of these zymotic diseases will be evident; but 

 how are we to protect ourselves when by chance such infection pollutes 

 our streams and wells? There is but one safe rule, and it is this: - 

 Use no water for domestic purposes which at any time contains sewage ; 

 because although normal sewage may not contain actually poisonous 

 substances, and may, when sufficiently diluted, be drunk with impunity, 

 as proved by Dr. Emmerlich and others ; yet we can never know when 

 diseased sewage containing morbific germs may enter such a water 

 course, and the only safe way is to have nothing to do with it. As I 

 have said this is really the only safe rule, but what shall we do when 

 we cannot help ourselves. To take our own case ; there is apparently 

 no other source from which we can obtain a supply than the Ottawa 

 river, and this receives the sewage of places like Aylmer, Quyon and 

 others; together with the drainage of fertilized fields all along its course, 

 and the fertilisers used are, as we know, not unlikely to contain disease 

 germs. Fortunately nature furnishes, in dissolved oxygen and through 

 other conditions, the means of self purification for such contaminated 

 waters. Only give time enough and the most dangerous sewage con- 

 tamination will be converted into harmless matter by natural agencies. 

 Still, it is reasonable to suppose that water containing much organic 

 matter in solution is more likely to furnish a suitable and congenial 

 nidus, or nourishing ground for bacteria than water that is more nearly 

 free from organic matter. This is the disadvantage at which we are 

 placed ; and I have no hesitation in saying that not only on aesthetic, but 



