528 VARIOUS FERTILITY FACTORS 



Many pot-culture and field experiments have been made with 

 calcium cyanamid which show that when properly used the nitrogen 

 in this form has about the same value as in ammonium sulfate. 



When heated with water under pressure, calcium cyanamid 

 decomposes with the formation of calcium carbonate and ammonia, 

 as indicated by the following equation: 



CaCN 2 + 3 H 2 O = CaCO 3 + 2 NH 3 . 



For long-distance shipping the final product from the artificial 

 fixation of atmospheric nitrogen is, in the opinion of the author> 

 to be ammonium nitrate, made by using the ammonia thus pro- 

 duced as a base for neutralizing the nitric acid obtained in the 

 Birkeland-Eyde process. 



NH 3 + HNO 3 = NH 4 NO 3 . 



The ammonium nitrate thus formed, free from mineral im- 

 purities, would contain 35 per cent of nitrogen. To produce this 

 compound would require five plants: (i) for nitrogen gas, (2) 

 for calcium carbid, (3) for calcium cyanamid, (4) for ammonia, and 

 (5) for nitric acid. 



A publication issued June i, 1907, by the American Cyanamid 

 Company, estimates that the original cost of a complete plant for 

 the production of 10,000 tons per annum of calcium cyanamid 

 would amount to $444,000, including: 



$155,000 for the calcium carbid plant, 

 70,000 for the Linde nitrogen plant, 

 145,000 for the calcium cyanamid plant, 

 74,000 for expense not itemized. 



This estimate of $444,000 does not include the cost of the 

 power plant, it being assumed that a separate company will be 

 organized to furnish the power by utilizing a natural waterfall. 



In connection with elaborated estimates as to the actual cost of 

 producing cyanamid nitrogen in such a plant, the following state- 

 ments are made in this publication : 



" Throughout all estimates of costs of operating it is assumed that power 

 costs the Cyanamid Company $15 per 24-hour horse power per annum, meas- 

 ured on the switchboard of the power company supplying the power. It is 



