1038 Synthetic Nitrogenous Fertilisers. [Feb., 



In order to meet this contingency he proposed that the supply 

 of nitrogenous fertilisers should be increased so as to ensure 

 progressive increases in crop yields. He further pointed out 

 methods by which nitrates could be made artificially. This 

 principle was carried into practice at Notodden in Norway and 

 subsequently at Niagara, where factories were erected and 

 considerable amounts of nitrates produced. For purposes of 

 Convenience nitrate of lime was made, although, as already 

 stated, nitrate of soda could equally well have been produced, 

 but at greater expense. 



The process requires considerable power, and the great 

 advantage possessed by Norway and Niagara, where cheap 

 water power is obtainable, is therefore evident. 



The second process, requiring somewhat less power, gives 

 rise to calcium cyanamide or nitrolim. This was first made 

 at Piano d'Orte in Italy, and is now produced at Odda in 

 Norway, Alby jn Sweden, at Niagara and elsewhere. 



Had the fertiliser problem alone been involved nitrate of lime 

 and nitrolim would probably have been the only fertilisers 

 produced synthetically, and their manufacture would have been 

 confined to places where cheap water power was available. 

 Just before the War, however, it was found that ammonium 

 nitrate could be used as a high explosive of very great 

 power, and the German chemists proceeded to devise 

 methods whereby it could be easily obtained in quantity from 

 the air. A satisfactory method was developed by Haber for 

 producing ammonia from the air, and a second process was 

 worked out by Ostwald for converting this into nitrate. The 

 necessary factory developments were made, and by the middle 

 of 1914 the process was working on a large scale at. the 

 Badische Anilin Fabrik, Ludwigshafen. The War naturally 

 caused remarkable developments in all the belligerent countries, 

 and in consequence the technical difficulties have been very 

 largely overcome. As a result the manufacturer is now able to 

 prepare the following substances, the nitrogen in each case being 

 derived from the air : — 



Nitrate of Lime, Chloride of Ammonia, 



Nitrate of Ammonia, Calcium Cyanamide, or Nitrolim, 



Urea. 



Nitrate of Lime. — This substance has been manufactured 

 in Norway since 1907, and has formed the subject of many 

 fertiliser trials in this country and abroad. An idea of the 

 rapidity with which its use was spreading before the War is 



