CYANAMID — manufacture:, CHE:MISTRY AND USES 33 



Flasks I and 2 were not inoculated with bacteria. Flask i 

 therefore shows that a solution of cyanamide, in the presence 

 of its derivatives, is not decomposed even upon months of 

 standing. The mere addition of lime in sterile conditions 

 causes a rapid decomposition of cyanamide. The effect of 

 lime is shown throughout by comparing the even-numbered 

 flasks with the odd-numbered flasks. 



Flask 7 shows that under sterile conditions, in the absence 

 of lime, a small amount of soil causes a small amount of 

 decomposition. Flask 5, which differs from flask 7 only in 

 the fact that the sterilizing agent, chloroform, was omitted, 

 shows that the presence of bacteria had no effect whatever 

 upon the decomposition. The same thing is shown by com- 

 paring flasks 6 and 8, in which lime was present. 



The larger values obtained in flasks 2, 3 and 4 seem to be 

 related in some way to the presence of secondary products, 

 that is, dicyandiamide, urea, and possibly amidodicyanic acid 

 and ammonia. Flasks i and 2 were both uninoculated, hence 

 the larger decomposition of flask 2 as compared with flasks 

 6 and 8 must be due to the simultaneous action of calcium 

 and secondary products of cyanamide. A separate experi- 

 ment showed, in fact, that the presence of 0.085 per cent, 

 ammonia in a solution of pure cyanamide containing 0.43 

 per cent, cyanamide effected the complete removal of the 

 cyanamide in 3 months at 30° C, while the cyanamide without 

 an ammonia addition remained constant. 



It is interesting to compare flask i with flask 3. These 

 differ in two respects, presence of soil and presence of nutri- 



