1912] The Ottawa Naturalist 169 



The water we drink may become, does in part become, 

 part and parcel of ourselves. The metabolism always going 

 on within us and resulting in growth, in the repair of waste, 

 in the production of energy, requires that every tissue of the 

 body should possess water. Thus, the blood that bathes every 

 tissue, and constitutes about one twelfth of the body weight, 

 is about 80 per cent, water. Of the body weight about 60 per 

 cent, is water. The adult individual requires five to six pints 

 of water, or its equivalent, daily. The consumption of certain 

 foods, such as milk, which is 85 per cent, water, of fruits and 

 vegetables which have a high water-content, lessen the volume 

 necessary to take as a beverage. 



With this knowledge of the part played by water in the 

 animal economy and its presence everywhere throughout the 

 system, it is not difficult to understand how polluted, foul 

 water may affect health. We are all aware now-a-days that 

 certain diseases, zymotic diseases as they are termed, are caused 

 by specific bacteria or germs. It may suffice to sav these 

 pathogenic bacteria having gained an entrance into the system, 

 through the water we drink.the food we eat or the air we breathe, 

 may and often do cause disease within us. It is the function 

 of the phagocytes, or white corpuscles of the blood, to combat 

 with and destroy these germs, and in good health, when we have 

 strong vitality, they perform their function well and keep us 

 free from disease. But, with a lowered vitality when the 

 host of intruders is too great and strong to battle with, 

 they may be beaten in the warfare and we succumb. Among 

 water-borne diseases the one we have to fear most is typhoid 

 fever. The excretal discharges of its victims are loaded with 

 its bacilli and when such waste finds its way into a water supply 

 the disease is disseminated and an epidemic results. Herein 

 lies the chief and great danger in using a supply polluted with 

 sewage or execretal waste. It must, however, be added that 

 water is not the only vehicle which conveys this disease; the 

 ubiquitous house-fly, as we know, must now bear its share of 

 the blame. 



But there is another danger in impure water, though of 

 this bacteriology takes no note. I refer to the presence of 

 certain poisonous substances, the products of the decomposition 

 of organic matter either of animal or vegetable origin. There 

 is good evidence that such polluted water may cause headache, 

 nausea, indigestion, diarrhoea, lassitude and generally lower 

 the vital tone of the system. It is quite true that such toxic 

 compounds have not been isolated, but I might answer that 

 such is the case with many ptomaines, organic compounds 

 occasionally occurring in our foods and especially in those 



