SOME RECENT TRIUMPHS 



an important place among the industrial metals, even 

 should it fall short of the preeminent position as 

 "the metal of the future" that was once prematurely 

 predicted for it. 



NITROGEN FROM THE AIR 



There is a curious suggestiveness about this finding 

 of aluminum at our very door, so to speak, some scores 

 of centuries after the relatively rare and inaccessible 

 metals had been known and utilized by man. But there 

 is another yet more striking instance of an abundant 

 element which man needed, but knew not how to obtain 

 until the science of our own day solved the problem of 

 making it available. This is the case of the nitrogen of 

 the air. As every one knows, this gas forms more 

 than three-fourths of the bulk of the atmosphere. 

 But, unlike the other chief constituent, oxygen, it is 

 not directly available for the use of plants and animals. 

 Yet nitrogen is an absolutely essential constituent of 

 the tissues of every living organism, vegetable and 

 animal. Any living thing from which it is withheld 

 must die of starvation, though every other constituent 

 of food be supplied without stint; and the fact that 

 the starving organism is bathed perpetually in an in- 

 exhaustible sea of atmosphere chiefly composed of 

 nitrogen would not abate by one jot the certainty of 

 its doom. 



To be made available as food for plants (and thus 

 indirectly as food for animals) nitrogen must be com- 

 bined with some other element, to form a soluble salt. 



[303] 



