CHEMISTRY. 223 



of phosphoric acid entering the solution from iron phosphate, but decreases the 

 amount entering the solution from aluminum phosphate. 



"Sodium nitrate decreases the amount of phosphoric acid entering the solution 

 Erom either iron or aluminum phosphate, but appears to slightly increase the amount 

 yielded by calcium phosphate, while it greatly increases the amount of calcium yielded 

 to the solution by the last-named substance. . . . 



"With pure water in contact with the phosphates the acidity of the resulting solu- 

 tions appears to be in the same direction as the concentration with respect to phos- 

 phoric acid, but no satisfactory correlation has been made between the two sets of 

 determinations. In solutions of more soluble salts in contact with the phosphates, 

 no generalization whatever seems justified. Potassium chlorid, potassium sulphate, 

 and sodium nitrate all increase the acidity of solutions in contact with iron phos- 

 phate, while potassium chlorid and sodium nitrate decrease the amount of the phos- 

 phoric acid in the solution. No correlation of the acidity with the amounts of iron 

 in the solution seems possible, although, as is shown by the solutions of potassium 

 chlorid, the base in solution is increased. 



"In contact with calcium phosphate, potassium chlorid, and sodium nitrate 

 decreased the acidity of the solution instead of increasing it, as in the case of iron 

 phosphate. In both cases, however, the amounts of calcium in the solutions decid- 

 edly increased, and in the case of sodium nitrate the phosphoric acid also. 



"Insofar as observations were made, an increase of temperature increased the 

 decomposition of the solid phosphates in either water or salt solutions. 



"Owing to the complexity of the reactions involved between the hydrolyzed 

 products and the other solutes, and perhaps also to the fact that definite equilibrium 

 conditions were not under observation, attempts to apply the mass law to the results 

 have not been satisfactory. The hypothesis of electrolytic dissociation has, in many 

 of the cases observed, failed to give a satisfactory explanation." 



A new method of rendering soluble the phosphoric acid in crude phos- 

 phates, A. Ystc;aard (Teknlsk Ugeblad, Chridiania, 50 (1903), X<>. 34, pp. 

 329-332). — Experiments were 'conducted by the author (see also E. S. R., 15, p. 1063) 

 for the purpose of rendering soluble the phosphoric acid of crude phosphates 

 (apatite) at a comparatively low temperature and without the aid of silica. The 

 effort was made to replace the lime in the phosphate with magnesia in the form of 

 carnallite (or carnallite and kieserite) , by which method 80 to 90 per cent of the 

 total phosphoric acid was rendered soluble in a 2 per cent citric-acid solution. 



By using bone ash as phosphatic material, in the place of apatite, as in the earlier 

 experiments, 96 to 98 per cent of the total phosphoric acid was rendered soluble in 

 citric-acid solution. 



In experiments on a larger scale, apatite, carnallite, and kieserite, in the propor- 

 tions of 1:2:1 were found to furnish a product that melted at about 650° C. and 

 hardened on cooling to a brittle mass that may be easily reduced to a fine powder. 

 The composition of this fertilizer was found to be as follows: Total phosphoric acid, 

 20.71 percent; citric-acid-soluble phosphoric acid, 15.23 per cent; chlorin, 16.47 per 

 cent; lime, 9.92 per cent; magnesia, 10.20 per cent; potash, 6.85 per cent. 



Comparative fertilizer trials with this fertilizer and basic phosphate for oats and 

 peas showed the former to possess a considerably higher value than the latter. The 

 yields obtained with the new phosphate were 123 of oats and 140 of peas, those 

 obtained with basic phosphate being placed at 100. — f. w. woll. 



Contribution to the knowledge of the action of sterile and fermenting 

 organic matter on the solubility of the phosphoric acid of tricalcium phos- 

 phate, A. Stalstrom (Centbl. Bakt. u. Par., 2. Abt., 11 (1904), \>. 724; ads. in Chem. 

 //;/.. 28 ( 1904), No. 45, Repert. No. 13, p. 158). — Experiments are reported which 

 show that organic substances, such as humus, sour milk, etc., when not sterilized, 

 dissolve tricalcium phosphate. 



