FIXED NITROGEN EESEARCH LABORATORY. 641 



CYANAMIDE. 



The direct product of the cyanamide process of nitrogen fixation 

 is calcium cyanamide. From this compound an extremely wide 

 variety of products is obtainable. Thus, in addition to cyanamide, 

 there may be obtained by transformation processes ammonia, nitric 

 acid (b}' ammonia oxidation), cyanides, hydrocyanic acid, cyanamide, 

 dicyanodiamide, urea, guanylurea, guanidine, etc.. and the numer- 

 ous derivatives of these latter compounds which are becoming im- 

 portant in the manufacture of dyes, drugs, and explosives. Many 

 of these important compounds can not be furnished in quantity by 

 j\ny other process. 



The laborator}' is making a rather extensive stud}' of the chemis- 

 try of cyanamide and its derivatives to open up this new and cheap 

 source of numerous, useful compounds. During the past year 

 methods have been developed for the production of free cyanamide 

 (H2CN2) in quantity, for the production of urea from cyanamide on 

 a semitechnical scale, and for the preparation of guanidine salts. 

 Cyanamide derivatives which appear to have value as ingredients in 

 explq^ives have also been studied and the results of the investigations 

 communicated to the ammunition division. Ordnance Office, War 

 Department. In addition, a theoretical investigation on the chem- 

 istry of cyanamide was made for the purpose of clarifying the 

 • chemistry of this large group of compounds. This investigation 

 is being continued. 



AGRICULTURAL UTILIZATION OF FIXED-NITROGEN COMPOUNDS. 



Very little information was available as to the agricultural value 

 of many of the new compounds which are now produced b}' nitrogen 

 fixation. In view of the possibility of operation of the Government 

 nitrate plants in the then near future, fertilizer experiments were 

 begun at Muscle Shoals and Sheffield, Ala., in 1919, in cooperation 

 with the Bureau of Plant Industry of the department. These experi- 

 ments were continued by the laboratory to the end of the 1921 season, 

 v>'hen thev were discontinued. An area of about 20 acres, divided 

 into nearly 500 plots, was used for these experiments, and the fol- 

 lowing nitrogen materials were tested, chiefly on cotton and corn: 

 Commercial cyanamide, ammonium nitrate, ammonium chloride, am- 

 monium phosphate, ammoniated superphosphate, double salt consist- 

 ing of ammonium nitrate and ammonium sulphate, chloride mixed 

 salt (made from ammonium nitrate and potassium chloride), sulphate 

 mixed salt (made from ammonium nitrate and potassium sulphate), 

 urea, calcium nitrate, and mixtures of calcium nitrate and cyanamide 

 in various proportions. Sodium nitrate and ammonium sulphate 

 served as standards for comparison. The results of these investiga- 

 tions are now being prepared for publication. 



Samples of a number of the above compounds have been prepared 

 for agricultural tests made by the soil fertility investigations section 

 and the tobacco investigations section. Bureau of Plant Industry, at 

 their various experimental fields. In addition, pot experiments have 

 been carried out in -cooperation with the soil fertilit}^ iuA^estigations 

 section to determine the effect on plant growth of numerous other 



