530 Intelligence and Miscellaneous Articles. 



The reaction is represented by the following equation : 

 2BrK + 5Br + Ph + 6K0 = PH0%K0 + 6BrH. 

 When bromine is replaced by iodine, and the alkaline bromide by 

 tlie iodide, an abundant and regular disengagement of hydriodic 

 acid is obtained : it is requisite merely to raise the temperature 

 slightly. — Ibid. 



QUANTITATIVE DETERMINATION OF PHOSPHOKIC ACID. 



M. Schulze determines the quantity of phosphoric acid in soils, 

 &c. by a process dependent on the following property : the phos- 

 phates of lime and of magnesia are soluble in acetic acid, whilst those 

 of peroxide of iron and alumina are insoluble in it. The addition of 

 a sufficient quantity of a solution of peracetate of iron or of acetate 

 of alumina, completely precipitates the phosphoric acid in combina- 

 tion with peroxide of iron or with alumina, from the phosphate of 

 lime and of magnesia dissolved by acetic acid. 



The acid liquor procured by treating soils with hydrochloric acid 

 usually contains a much larger quantity of alumina and peroxide of 

 iron than corresponds to the quantity of phosphoric acid. Conse- 

 quently, if after the oxidation of the iron the excess of acid is super- 

 saturated with ammonia, and the peroxide of iron, alumina and com- 

 pounds of phosphoric acid are thus precipitated, all this acid will 

 remain in an insoluble state, combined with peroxide of iron and 

 alumina, on the subsequent addition of excess of acetic acid and the 

 application of heat ; while the rest will dissolve. — Ibid. 



NEW MINERALS. — ANDESINE*. 



M. Abich has analysed a mineral from the Andes which was called 

 Pseudo-albite on account of its having been found in twin crystals 

 very similar to albite. Its cleavage, however, is less distinct than 

 albite, and the cleavage planes are more undecided and less angular. 

 This mineral is imbedded in a whitish gray mass called andesite, of 

 sp. gr. 3-5924, mixed with hornblende and quartz ; the crystals, when 

 broken out, leave a shining impression. The specific gravity is 3'7328, 

 therefore greater than that of albite. Separates before the blow- 

 pipe into thin fragments, and fuses into a porous drossy bead. 



Analysed vidth carbonate of barytas it gave. 



Oxygen. 



Formula R S , -H 3 A S.. 



It is therefore a leucite, in which the potash is replaced princi- 

 pally by soda and lime. 



• Berzelius, Jahresbericht, and Journal fiir PruktkcJie Cheinie. 



