50 CYANAMID — MANUFACTURE, CHEMISTRY AND USES 



Analcimite of Tyrol, hydrated trisilicate of aluminium and 

 sodium. 



Cabasite of Nova Scotia, hydrated trisilicate of aluminium 

 and calcium. 



Each zeolite was ground in a mortar and made to pass a 

 screen of fineness Kahl. oo. 



One hundred grams of each zeolite was placed in glass tubes 

 moistened with 20 cc. of a 4.2 per cent, solution of cyanamide 

 (2.8 per cent, nitrogen). A fifth tube without zeolite was used 

 as a control. After 12 days in a thermostat the solutions were 

 analyzed with the following results: 



Cyanamide 

 Initial after 



cyanamide 12 days 



grams grams 



Solution alone 0.0840 0.0836 



** natrolite 0,0840 0.0235 



** scolecite 0.0840 0.0148 



" analcimo 0,0840 0,0158 



'* cabasite 0.0840 0.0168 



This experiment shows that the crystalline zeolites possess 

 to a high degree the ability to transform the cyanamide, from 

 which we may conclude that the colloidal zeolites as they exist 

 in the soil must have a still greater ability. The crystalline 

 zeolites, according to Zambonini,^ have a structure analogous 

 to that of the hydrosols, and according to Von Weimarn^ may 

 act like colloidal substances. 



EFFECT OF CARBON. 



Ulpiani next desired to learn what effect would be obtained 

 with a material exposing a large surface, but of no chemical 

 activity towards cyanamide. For this purpose a commercial 

 animal carbon was washed with hydrochloric acid and then 

 with water until free from acid, and was dried in an oven at 

 110° C. In order to obtain a wetting comparable to that in 

 the experiments with soil, 50 grams of carbon was moistened 



^ Atti. R. Ace. Lincei, XVIII. fasc. II, 1st Sem, 1909. 



2 Koll. Zeit. Vol. VI, No, i, 1910, 



