TRANSACTIONS OF WAGNER 



FOOD FROM THE AIR 



properly balanced ration of these is antagonistic to excellent mental and bodily 

 health. On the other hand, it cannot be denied that abstention from animal 

 food is consistent with equally high development of normal human powers. 



It is a primary principle in biology that plants are intermediate to man and 

 the earth. It is the plant that works up the inorganic materials, carbon dioxid, 

 water, phosphates and nitrates, into forms, principally proteins and carbo- 

 hydrates, upon which herbivorous animals feed, convert into other substances, 

 and become in turn the food of carnivorous animals. After death, all organ- 

 isms are converted into inorganic materials and the cycle of rebuilding is re- 

 sumed. 



It is obvious, therefore, that the maintaining of human life is absolutely 

 dependent on maintaining vegetable life, so that in the last analysis the earth 

 becomes the only source of wealth. The last hundred years have witnessed 

 an enormous growth of population and its concentration in cities at an increas- 

 ing rate. The area of land under active cultivation has not increased in the 

 same ratio as the number of those who are wholly dependent on it for food and 

 are unable to assist in such production. Statistics collected by the United 

 States government show clearly that the production of food-animals has not 

 kept pace with the increase of population. Altho some of the advance in 

 the price of meats and dairy products is due to trust-control, aided by the 

 methods of cold storage, both for withholding perishable articles and for 

 facilitating transportation to other countries, these conditions are not alone 

 to blame. There is a real relative scarcity. Moreover, the extension of sani- 

 tary control has increased the cost of production of many forms of food and 

 diminished the return, for, as regards meats, for instance, many a carcass that 

 formerly went to the market now goes into the fertilizer vat. 



High fertility of land depends on the presence of certain classes of inorganic 

 substances, and on certain types of living organisms. While much remains to 

 be determined as to the best conditions of plant growth, and, indeed, it is well 

 known that different conditions are required for different types of plants, it is 

 now pretty well established that the plants that form part of the food of man, 

 and of the herbivorous animals commonly eaten by him, require three types of 

 inorganic materials: compounds of phosphorus, potassium, and nitrogen. 

 While many forms of these compounds are capable of being utilized, a few of 

 them are especially adapted, and it is the endeavor of the agriculturist to obtain 

 soils in which such compounds are present or to add them if lacking. Phos- 



