104 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 17 
Mr. H. A. Gossard : Do I understand that nicotine was used and dry 
lime sulphur also? 
Mr. S. W. Frost: During the summer applications nicotine was not 
used. It was used in the delayed dormant spray. 
President A. G. Ruggles: Mr. William Moore will now present a 
paper. 
CALCIUM CYANIDE 
By William Moore, A merican Cyanamid Company , New York City 
Abstract 
A discussion of the methods of manufacture, chemical composition and the 
reactions which make this compound a promising insecticide. 
During the past season many entomologists have been experimenting 
with calcium cyanide as an insecticide. Promising results have been 
obtained using calcium cyanide as a contact dust or rather as an open air 
fumigant. Several insects for which there is no other satisfactory 
method of control have been successfullv combatted with this material. 
« 
In the form of dust, granular material or flakes it has been tested for the 
destruction of rodents, the leaf cutting ants of South America, various 
insects normally treated with contact dusts or liquids, fleas, chinch 
bugs, subterranean insects, crayfish and nematodes. Altogether con¬ 
siderable interest has been shown in calcium cyanide hence, a brief paper 
on what it is, how it is made and its reactions should prove of interest. 
Manufacture and Chemical Composition of Calcium Cyanide 
A better understanding of the material may be obtained by briefly 
sketching its manufacture so as to obtain its relationship to other well 
kflown materials. Calcium carbide is made from lime stone and coke. 
Air is liquefied and the nitrogen boiled off leaving the oxygen. The 
nitrogen is then absorbed in white hot powdered calcium carbide form¬ 
ing cyanamid, Ca CN 2 . The next step in the process is the fusion of the 
calcium cyanamid with sodium chloride in an electric furance heated to a 
high temperature, when the cyanamid is converted to cyanide. 
The finished product is in the form of thin flakes about a millimeter in 
thickness. The color is black due to a small amount of carbon in the 
form of graphite. The cyanogen content is equivalent to about 48%- 
50% sodium cyanide. The product is a crude cyanide consisting of 
calcium, sodium, cyanogen, and chloride. It is generally considered as 
having the cyanogen combined with the calcium in the form of 
calcium cyanide while the sodium and chloride are combined as sodium 
chloride. Due to its method of manufacture there are traces of calcium 
