1908.] Experiments with Calcium Cyanamide. 659 



caked at all after lying up in bags for two months and a half. 

 The various mixtures are all light friable powders, rather drier 

 than the original superphosphate and in perfect condition for 



sowing by hand or drill. 



Experiment. 



Mixture in lb. 



Temperature °C. 



Loss of Weight, lb. 



Cyanamide. 



Super- 

 phosphate. 



Starting. 



Maximum 

 in heap. 



After 

 Mixing. 



After 

 Storage. 



No. 1 



11 



224 



i6-5 



53 



5 



12 



„ 2 



22 



224 





87* 



5 



12 



„ 3 



44 



224 



18 



not 



28 



29 



„ 4 



56 



112 



13 



95i 







,; 5 



56 



II2§ 



13 



9311 







* After 6 hours. + After 1 1 hours. J After 2| hours. 



§ Also 20 lb. water. |l After I hour. 



Samples were taken from the first three mixtures and analysed 

 with the following results, in which comparison is made between 

 the figures obtained by analysis and the figures calculated 

 on the assumption that no loss of fertilising material had taken 

 place, after due allowance had been made for the shrinkage in 



weight due to the loss of water on mixing. 









Phosphoric Acid. 





Nitrogen. 

















Citric Acid Soluble. 









Water Soluble 













(Found). 









Calculated. 



Found. 





Calculated. 



Found. 



Cyanamide 





17-24 









Superphosphate 







11-48 





12-68 



Mixture I 



0-864 



0-852 



6-66 



12-35 



11-65 



„ II .. 



1*540 



1-630 



i-6 5 



12* 14 



1 1 - 22 



„ III 



3-080. 



3'054 





n-88 



10-57 



Allowing for the errors introduced by mixing and sampling, 

 these results are quite consistent and lead to the following 

 conclusions : — 



( 1 ) There is no loss of nitrogen ; any ammonia that is generated 

 on the slaking of the lime is at once fixed by the superphosphate. 

 This conclusion is confirmed by the observation that not 

 the least smell of ammonia could be detected during mixing 

 or arising from the heap after mixture, except in mixtures 4. 

 and 5 where an excess of cyanamide was used. 



