220 EXPERIMENT STATION EECOED. 



which contained 10 per cent potassium nitrate and 100 gm. of sifted soil are 

 reported. 



The results show that the calcium cyanamid in its lowest concentration 

 markedly decreased denltrification. This is thought to explain the more durable 

 and uniform action of calcium cyanamid when used as a fertilizer by other 

 investigators as compared with that of ammonium sulphate and sodium nitrate. 

 It is also thought that inorganic nitrogenous fertilizers can be best utilized 

 when mixed with calcium cyanamid as the latter acts both as a nitrogenous 

 fertilizer and a retarder of denltrification. 



Nitrate deposits in southern Idaho and eastern Oregon, G. R. JIaxsfikld 

 {U. -S'. Geol. Survey Bui. 6.20-B (lUlo). pV- J!>-'i'i. pJ'<- 2, fig. i).— This paper 

 reports the occurrence of nitrate deposits near Homedale, Idaho, located in the 

 canyons of Sucker Creek and Jump Creek and describes the geography and 

 geology of the region. 



The nitrates are always associated with rhyolites. The nitrate occurs in 

 little veinlets which form only a small part of the whole mass. It is thought 

 probable that the Homedale nitrate district is only a part of a much larger niter- 

 bearing area in which locally, as at Sucker Creek, the niter occurs in notable 

 amounts. Enough work has not been done to justify a positive statement re- 

 garding the economic value of the deposits. 



Preparation of the phosphate extracted by sulphurous acid from Viatka 

 phosphate, V. P. Kochetkov (/~ liczuVt. Vcuct. Opi/tov Lab. Rabat, 9 {IdlS), 

 pp. 1-20). — These experiments included tests of the dissolving action of sul- 

 phurous acid on the phosphoric acid of phosphorite and the precipitation of the 

 sulphurous solution by (1) evaporation of the solution to dryness, (2) elimina- 

 tion of excess sulphur dioxld Ity boiling, and (3) precipitation of the phosphate 

 with lime. 



It was found that passing a current of sulphurous acid through phosphate sus- 

 pended in water almost completely dissolved the phosphoric acid. The addition 

 of sulphuric acid to the water in an amount hardly sulRcient to decompose the 

 calcium carbonate of the natural phosphate was found to increase the dissolving 

 power of sulpluirous acid for phosphoric acid. After evaporation to dryness the 

 residues contained from 22 to 24 per cent of phosphoric acid, of which 57 to 80 

 per cent was soluble in citric acid. Boiling the solution resulted in the precipita- 

 tion of about half of the phosphate dissolved, which contained from 23 to 36 per 

 cent of phosphoric acid. The other half of the dissolved phosphate was pre- 

 cipitated by milk of lime, the product "containing from 16 to 26..5 per cent phos- 

 phoric acid, of which from 86 to 94 per cent was soluble in citric acid. 



Speed of solution of compounds of potassium, aluminum, and iron of natural 

 phosphates by mineral acids, I, A. V. Kazakov (/~ Rczul't. Vcfict. Opiitor Lab. 

 Rabot, 9 {1013), pp. 21-/(5, pi. 1, figs. 8). — A review of the fundamental princi- 

 ples underlying the speed of chemical phenomena in general and of the solution 

 of solid bodies in particular and a review of literature bearing on the subject are 

 followed by a report of experiments to determine the role of concentration of the 

 solvent, duration of the reaction, degi'oe of pulverization of the phosphate, pre- 

 liminary roasting of the phosphate, and rapidity of introducing the solvent on 

 the speed of dissolution of potassium, aluminum, and iron of four different 

 natural phosphates. The solvents use<l in different concentrations were sul- 

 pliuric, hydrochloric, and phosphoric acids. The results are gi-aphically reported. 



Mechanical enrichment of natural phosphates in calcium phosphate, A. V. 

 Kazakov (Iz RczuVt. Vcgct. Opytov Lab. Rabot, 9 (1913). pp. 46--5G. figs. 7).— 

 Experiments on six series of typical natural phosphates are reported, the object 

 of which was to determine the effect of grinding and sifting into two fractions 

 and of roasting on the phosphoric-acid content of the two fractions. 



