CYANAMID — manufacture;, CHEMISTRY AND USES 99 



gen and of nitrogen in the distillate represents the availability. 

 By this method the sample used in these experiments gave 

 90.20 per cent, availability. 



C. S. Cathcart, State Chemist at the New Jersey Agricultural 

 Experiment Station, made some experiments with samples of 

 powdered Cyanamid, using the regular modified alkaline per- 

 mangate method, with the following results. 



Sample number 284 285 294 295 308 



Per cent. Per cent. Per cent. Per cent. Per cent. 



Qualitative test for nitrates . none none none none none 



Total nitrogen. 15.76 13.57 13.29 14.00 16.40 



Nitrate and ammoniacal 



(Ulsch-Street) 6.98 5.53 3.50 4.72 7.32 



Ammonia salts (magnesia). . 0.92 0.57 0.45 0.55 0.91 



Water soluble (total) 14.15 11.93 12.23 12.88 14.67 



Water insoluble 1.25 1.64 1.06 1.12 1.73 



Active insoluble (distilled 

 from alkaline permanga- 

 nate) 0.17 0.17 0.25 0.32 0.33 



Inactive insoluble 1.08 1.47 0.81 0.80 1.40 



Total nitrogen as water solu- 

 ble and active insoluble. 93.1 ^9.2 93.4 94.3 91.5 



It is interesting to note that as much as 40 per cent, of the 

 Cyanamid nitrogen is converted to ammonia by the reducing 

 action of the iron and sulphuric acid used in the Ulsch-Street 

 method.^ The amount of ammoniacal nitrogen originally pre- 

 sent is shown by magnesia distillation to be from 3 to 6 per 

 cent, of the total nitrogen. The qualitative test showed no 

 nitrates present. 



The water-soluble nitrogen with one washing of 250 cc. 

 distilled water is from 87 to 92 per cent, of the total, the 

 average being 90.6 per cent. By treatment with alkaline per- 

 manganate the available nitrogen is found to be 92.5 per cent, 

 as an average of the five samples. 



In order to determine the effect of a more thorough initial 

 washing, Cathcart repeated the availability experiments wash- 

 ^ For Ulsch-Street Method see U. S. Dept. of Agr. Bureau of Chem., 

 Bui. 107., or Wiley's Principles and Practice of Agricultural Analy- 

 sis, Vol. I, p. 445. 



