SAFEGUARDS OF THE BODY 141 



on hand in our mysterious insides the latent power of 

 protection against all the special forms of disease- 

 producing bacteria which wander the earth? How 

 does it fit into physiology ? Or can we indeed create 

 new protective powers in the stress of such varied 

 accidents as new infections involve? 



We have seen that the diphtheria bacillus produces 

 its deadly effects through a poison which it sets free 

 as it grows in the body. In order to understand how 

 this poison is rendered harmless, we must know how 

 it damages the delicate body cells. So we must go 

 back to the cell for a moment. These cells in the 

 living body sit in their respective places, and as the 

 nutrient fluids pass and bathe them, each of them 

 being a powerful little chemical factory, they seize up- 

 on whatever nutrient molecules they require, and out 

 of these build up such new substances as they need in 

 their business, whether this be self-nutrition, or the 

 storage of energy, or the furnishing of special life- 

 stuff for their neighbors. So each cell is armed with 

 this power of forming chemical union with the food. 



But suppose something comes along in the body 

 fluids with which the cell can and does form the same 

 sort of chemical union, but which is not a food; on 

 the contrary, damages the cell that is, is poisonous 

 or toxic for it. The cell suffers, of course first, by 

 the direct damage, and, second, by the loss of its 

 food-securing capacity. The latter it has used up in 

 uniting with the poison. 



