8 BULLETIN 37, U. S. DEPARTMENT OF AGRICULTURE. 
tons sodium nitrate were exported. The total production of nitrates, 
calculated to a basis of calcium nitrate, is equivalent to about 22,000 
tons. During the year 1911, 2,302 tons calcium nitrate were imported 
into the United States. 1 
CALCIUM CYANAMIDE. 
Calcium cyanamide is perhaps the most nitrogenous material manu- 
factured for fertilizer purposes. It is prepared from calcium carbide 
and free nitrogen, the latter being prepared from the atmosphere by 
the removal of oxygen. The reaction between the two substances 
may be represented by the following equation: 
CaC 2 + N 2 = CaCN 2 + C 
Calcium carbide Calcium cyanamide 
The product is a gray powder. In addition to nitrogen it contains 
a high percentage of calcium and some finely divided carbon. In the 
soil it reacts with water to produce urea and lime, the former being 
acted upon further to form ammonia. 
Table IX. — Installations for manufacture of calcium cyanamide by the Frank and Caro 
process. 
Name of company. 
Place of installation. 
Output per 
annum. 
Nitrogen Fertilisers Co. (North- Western Cyanamide Co.) 
Do.. 
Societa Italiana de Prodotti Azotate 
Society Italiana per il Carburo de Calcio 
Societa Piemontese per il Carburo de Calcio 
Socidte" Francaise pour les Produits Azotes 
Do 
Bayerische StickstofE Werke 
Ost-Deutscher StickstofTcale und Chemische Werke 
A. G. Stickstoffdunger , 
Society per l'Utilizzazione della Forze Idrauliche della Dal 
mazia. 
Do 
Japanese Nitrogen Products Co 
American Cyanamide Co 
Do 
Odda, Norway 
Alby, Sweden 
Piano d'Orto, Italy 
Terni, Italy 
San Marcel, Italy 
Martigny, Switzerland. . . 
Notre Dame de Briancon 
Trostberg, Bavaria 
Bromberg, Prussia 
Knapsack, Germany 
Selenico, Dalmatia 
Dugirat, near Almissa 
Kinzei ; near Osaka , 
Nashville, Term 
Niagara 
Tons. 
15,000 
15.000 
4.000 
15,000 
3,000 
7,500 
7.500 
15.000 
2.500 
18.000 
4,000 
80.000 
4,000 
4,000 
12,000 
The composition of commercial calcium cyanamide is given in 
Table X. 2 
Table X. — The composition of commercial calcium cyanamide. 
Constituent. 
Proportion. 
Constituent. 
Proportion. 
Per cent. 
45 
4 
27 
1 
14 
Per cent. 
2 
Silica ( Si0 2 ) 
2 
4 
1 
1 Morton, "Utilization of Atmospheric Nitrogen, 
Series No. 52. 
» Pranke, J. Ind. Eng. Chem., 5, 159 (1913). 
Bull. Dept. Commerce and Labor, Special Agent 
