SYNTHETIC CHEMISTRY 



against another invasion. Indeed, in augmenting 

 the defensive powers of man, the influence of his 

 fecund labors was felt even in the struggle in South 

 Africa. 



If science, industry, humanity, alike stand in his 

 debt, to them must be added agriculture as well. 

 The remarkable range of his interests found new 

 vent in the purchase of a slender plot of ground on 

 the outskirts of Paris for the laboratory of vegeta- 

 ble chemistry of Meudon. Here, a quarter of a 

 century ago, he began yet another line of chemical 

 investigation, which already seems likely to double 

 or quadruple the fertility of the earth. 



One of the four elements from which all living 

 matter is built up is the inert nitrogen of the air 

 we breathe. It seems not assimilated by animals; 

 exact measures disclosed that in the nutrition of 

 plants the atmospheric nitrogen does not intervene 

 in the least. The nitrates and salts of ammonia, 

 which are the condition and almost the chemical 

 sign of life, seem borrowed from the soil. It is the 

 presence of these which determine whether a soil 

 is rich or poor. The carbonic acid in the air sup- 

 plies the carbon ; the rain, the hydrogen and oxy- 

 gen ; and the sunlight, the energy. That the plant 

 manufactory of hydrocarbon compounds, the food 

 nf animals and man, may go on, the nitrates of 

 the soil must be renewed. A banker paying out 



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