CYANAMID COMPOUND AS A FERTILIZER 307 



for the preparation of cyanamid uses carbon in the solid state or 

 in the form of hydrocarbon gas, and an alkali amid; or NH 3 

 brought in contact with a melted alkali metal and charcoal at 

 4OO-6oo . In this way, alkali amid is formed which under the 

 action of a portion of the charcoal becomes alkali cyanamid. 70 



Calcium cyanamid (the formula of which when pure is CaCN 2 ) 

 is a black powder, resembling basic slag in other properties and 

 containing over 20 per cent. N, readily soluble in H 2 O, besides 

 more or less CaO, CaC 2 and C. 



Gerlach found it to be equal in manurial value to XaXO.. 

 and (NH 4 ) 2 SO 4 in pot experiments with barley and white mus- 

 tard, though in field experiments its value fell to 74 (NaNO 3 = 

 ioo). 71 With peaty soils, calcium cyanamid acts injuriously, due 

 probably to the formation of dicyanodiamid by the organic acids, 

 unless the application of the manure be made five or six weeks 

 before sowing. 



This early application causes a loss of nitrogen, which should 

 be taken into account in reckoning its value. 



Otto found it nearly as efficacious as sodium nitrate when 

 used with spinach or cabbage, and better than nitrate or ammoni- 

 acal nitrogen in fertilizing maize. 72 



Hall in comparing it with ammonium sulfate for fertilizing 

 mangels, swedes and mustard, obtained favorable results. 73 



The best way to determine the nitrogen in calcium cyanamid is 

 to digest it with strong sulfuric acid by the usual kjeldahl process. 



CaCN 2 decomposes in the soil into CaCO 3 and NH 3 ; this 

 makes the soil alkaline ; therefore it is better to use acid phos- 

 phate than disodium phosphate. 74 



269. Cyanamid Compound as a Fertilizer. Experiments have 

 been conducted by Shutt and Charlton at the agricultural ex- 

 periment station at Ottawa to determine the value of cyan- 

 amid compound as a fertilizer. The effect of the compound 



70 Robine and Lenglen, The Cyanid Industry, Translated by LeClerc , 

 1906 : 176. 



71 Biedermann's Central-Blatt, 1904, 33 : 649. 

 77 Chemisches Central-Blatt, 1905, I : 117. 



73 Journal of Agricultural Science, 1905, 1 : 146. 



74 Inamura, Bulletin of the College of Agriculture, Tokyo, 1906, 7 : 53- 



