ABSORPTION OF NITROGEN FROM SOIL AND AIR 65 



method of fixing atmospheric nitrogen by combining it with 

 hydrogen, thus forming synthetic ammonium. At the present 

 time, there are in operation in Europe several factories which 

 produce hundreds of thousands and even millions of tons of 

 synthetic ammonium salts, and it is very likely that in the near 

 future the requirements of agriculture will be fully satisfied by 

 artificial nitrogenous fertilizers produced from the air. Then the 

 increase of yields will not depend, as heretofore, on the growing of 

 nitrogen-gathering leguminous plants. 



