WATER 21 



premises that gain access to sewers excepted, and human typhoid 

 is non-existent among our animals. But, is the presence of specific 

 organisms that are known to be pathogenic necessary for the pro- 

 duction of " ill health " ? Is it safe for people to drink sewage 

 known not to contain the specific bacteria that are pathogenic to 

 mankind ? It has been held in court that damage to health of cattle 

 through pollution might be established without any special ailment 

 being proved, but one would want to be satisfied that every other 

 possible cause of illness had been eliminated. It has been suggested 

 that the ingestion of putrefactive bacteria and their products, such 

 as are found in sewage, cannot do harm to animals as the normal 

 and healthy alimentary tract is teeming with putrefactive organisms 

 and that a few more can do no harm. 



While one is not prepared to accept this reasoning as altogether 

 conclusive, it is certainly a fact that animals time and again drink 

 very filthy water and water containing sewage, and apparently 

 suffer no ill at the time. Cows on sewage irrigation farms con- 

 stantly eat, under the soiling system, grass fresh cut from the irriga- 

 tion beds, and frequently wet with undiluted sewage. The author 

 knows of such a farm that is particularly foul and " sewage sick," 

 the grass of which, when it is cut and fed to the cows, has a most 

 unpleasant smell, and yet the animals apparently suffer no ill. That 

 it is undesirable for dairy farms to be located on sewage farms 

 few will dispute, but the fact remains, that so far as the cows are 

 concerned, there appears to be nothing against the practice. This 

 is a strong argument, unwelcome though it is, that sewage water 

 is harmless to stock. The position, in short, appears to be this, 

 that though there is no real proof that sewage-polluted water is 

 harmful to animals, no one, on the other hand, can say with cer- 

 tainty that it is free from danger. Whatever proof there may 

 or may not be with regard to definite illness produced by drinking 

 filthy water, the fact remains that pure water is always more desir- 

 able than polluted water, as we know that the former cannot cause 

 harm, while the latter may do so. 



Lack of proof that sewage-polluted water does cause illness does 

 not, fortunately, leave the way open for public authorities or private 

 persons to pollute streams as this is prohibited by the Rivers Pol- 

 lution Prevention Act. 



THE EXAMINATION OF WATER AND WATER SUPPLIES. 

 There is a very common idea that if a person fills a bottle with 

 water from a well, or a stream, or out of a tap and sends it to a 

 chemist, the chemist, by making an analysis, can say with certainty 



