CHAPTER XIX 



Phosphates and Nitrogen 



Phosphorus, that terrible poison, is found 

 abundantly in the bodies of all animals, 

 especially in the bones from which all that is 

 now used is derived. It exists in meat, in 

 milk and in cheese, in plants — above all, in 

 cereals — so that it is contained in flour and 

 bread. But we need feel no alarm ; we shall 

 not die poisoned like the rats that eat the 

 phosphorated crusts. 



When two or more substances are com- 

 bined, they lose their original properties, 

 and the combination possesses other pro- 

 perties altogether different from these. 

 Thus carbon, when combined with the air 

 that we breathe, becomes an invisible, subtle 

 and unbreathable gas ; and lime, which has a 

 burning taste, in combination with carbonic 

 acid gas, becomes chalk, which is quite taste- 

 less. And substances of which the least 

 amount is fatal may, when combined with 



107 



