4 CYANAMID — MANUFACTURE, CHEMISTRY AND USES 



Cyanamid. — This is a trade name for the completely hydrated 

 material prepared for use as a fertilizer in the United States. 

 It contains about 45 per cent, calcium cyanamide, 27 per cent, 

 calcium hydroxide and no carbide. The name is always 

 capitalized and has no final "e." 



Cyanamide. — The compound represented by the formula 

 CN.NHo. It is sometimes referred to as acid cyanamide, or 

 free cyanamide. 



Calcium Cyanamide. — The chemical compound of the for- 

 mula CN.NCa, or CaCNa, as it is freqently written. 



Calcium Cyanamid. — The name used by the United States 

 Department of Agriculture and by some State Departments of 

 Agriculture to designate commercial Cyanamid. It is some- 

 times used to indicate the substance represented by the formula 

 CN.NCa, but for the sake of clearness the compound CN.NCa 

 will be called calcium cyanamide in the present paper. 



Nitrolim. — The trade name for the material sold in England 

 for agricultural purposes. It is a lime-nitrogen to which has 

 been added just enough water to destroy the carbide. Practi- 

 cally all the free lime is present as calcium oxide. 



Kalkstickstoff. — The commercial material manufactured in 

 Germany for use as a fertilizer. It is similar to nitrolim. 



Stickstoffkalk. — A crude calcium cyanamide made by nitri- 

 fying a calcium carbide which contains about 10 per cent, of cal- 

 cium chloride. Its manufacture in Westeregeln, Germany, 

 under the Polzeniusz patents was discontinued in 1910. 



Calciocianamide. — The Italian commercial product, com- 

 pletely hydrated. 



Cyanamide de calcium. — The French commercial product, 

 completely hydrated. 



MANUFACTURE OF COMMERCIAL CYANAMID. 



The first step in the manufacture of Commercial Cyanamid 

 is the preparation of calcium carbide. This is brought about 

 in the usual manner by fusing in an electric furnace a mixture 

 of lime and coke in accordance with the following equation : 



