358 



Our Surroundings 



Nutrients 



over-estimated. Water is indispensable to life. It constitutes 

 over sixty per cent of the weight of the body. Without its 

 aid as a transporting agent the cells of the body cannot be 

 supplied with food, and the wastes of the body cannot be car- 

 ried away, for food is available to the cells only when in solu- 

 tion, and wastes cannot be removed from them unless in soluble 

 form. 



In ordinary water there are always some harmless germs. 

 Sometimes there are disease germs which thrive on decaying ani- 

 mal matter in water. Such germs usually find their way into the 



