NITRIC ACID 9 



an efficient method for producing nitric acid has 

 thus been developed, but the scale of production, 

 although sufficiently formidable in peace time, 

 does not suffice for war requirements. Since the 

 outbreak of war a process has been perfected in 

 Germany for manufacturing ammonia by the 

 direct combination of nitrogen and hydrogen in 

 very large quantities ; further, a method has been 

 elaborated for the economic conversion of ammonia 

 into nitric acid, so that it would appear that the 

 efforts of the German chemists have rendered their 

 country independent of foreign raw materials for 

 the manufacture of nitric acid. As bearing upon 

 this question it may be noted that the military 

 boards of the United States have estimated their 

 requirement of nitric acid, in case of war, at 180,000 

 tons per annum ; this quantity can be produced 

 by utilising another 100,000 horse power out of 

 the 1,000,000 which can still be drawn from the 

 Niagara Falls without affecting the scenic value of 

 the cataract. The economic importance to chemical 

 technology of large supplies of water power is ob- 

 vious ; it is instructive to observe that the Zambesi 

 Falls, situated in British Territory, are capable of a 

 much larger output of energy than those of Niagara. 

 The intricate manner in which many different 

 national interests are interlocked through the 

 medium of the chemical industries has been already 

 remarked. The close relationship between the 

 artificial production of indigo, the manufacture of 



