then precipitated a fourth time with barium hydroxide and after that 

 two more times with alcohol. It was then filtered, washed free of 

 chlorides with dilute alcohol and then in alcohol and ether and dried in 

 vacuum over sulfuric acid. The product was then a nearly white, cry- 

 stalline powder and it weighed 94 grams. 



The dry substance was shaken up with about 1.5 liters of cold water, 

 allowed to stand for several hours and then filtered and washed in 

 water. The aqueous solution contained very little substance precipitable 

 with alcohol and it was therefore discarded. 



The washed precipitate was dissolved in dilute hydrochloric acid 

 and precipitated a fifth time by the very gradual addition of barium 

 hydroxide; after filtering and washing, this operation was repeated a 

 sixth time. After again dissolving in dilute hydrochloric acid, nearly 

 neutralizing the free acid with barium hydroxide and filtering, the sub- 

 stance was brought to crystallization by the gradual addition of an equal 

 volume of alcohol. After standing for several hours the substance was 

 filtered and washed in dilute alcohol, alcohol and ether and dried in 

 vacuum over sulfuric acid. It was then a voluminous snow-white cry- 

 stalline powder. 



The dry substance was again dissolved in dilute hydrochloric acid, 

 the free acid nearly neutralized with barium hydroxide and the solution 

 filtered and allowed to stand over night. The substance soon began to 

 crystallize. Under the microscope it appeared perfectly homogeneous 

 and consisted as before of globular masses of microscopic needles. The 

 substance was filtered, washed free of chlorides with water and then in 

 alcohol and ether and dried in vacuum over sulfuric acid. The dry, 

 snow-white, crystalline powder weighed 69 grams. 



Qualitative analysis failed to reveal any heavy metals other than 

 barium and from 0.5 gram of the salt no weighable residue of alkali was 

 obtained. It gave no reaction with ammonium molybdate in nitric acid 

 solution. It was free from sulfur and nitrogen. 



It was analyzed after drying at 105° in vacuum over phosphorus 

 pentoxide. 



0.4641 gram substance gave 0.0556 gram H 2 and 0.1125 gram C0 2 . 



0.1982 gram substance gave 0.1333 gram BaS0 4 and 0.1203 gram 

 Mg 2 P 2 7 . 



Found: C = 6.61; H = 1.34; P= 16.91; Ba = 39.57 per cent 



For tribarium inosite hexaphosphate : 



QH 12 24 P e Ba 3 = 1066. 



Calculated : C = 6.75 ; H = 1 . 12 ; P = 17.44 ; Ba = 38.65 per cent. 



A portion of this salt was re-crystallized as follows : 5 grams were 

 dissolved in a small quantity of 5 per cent, hydrochloric acid and the free 

 acid nearly neutralized with barium hydroxide, the solution was then 

 filtered and 2 grams of barium chloride dissolved in a little water added 



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