New York Agricultural Experiment Station. 349 



For analysis it was dried at 105° in vacuum over phosphorus 

 pentoxide. 



0.2931 gram subst. gave 0.0365 gram H 2 and 0.0714 gram C0 2 . 

 0.1743 gram subst. gave 0.1144 gram BaS0 4 and 0.1073 gram 

 Mg 2 P 2 7 . 



Found: C = 6.64; H = 1.39; P = 17.15; Ba = 38.62 per ct. 

 For tribarium inosite hexaphosphate C 6 Hi 2 24 P 6 Ba3 = 1066. 

 Calculated: C = 6.75; H = 1.12; P = 17.44; Ba = 38.65 per ct. 



The above salt was recrystallized as follows: 5 grams were dis- 

 solved in the least possible quantity of about 3 per ct. hydrochloric 

 acid and the free acid nearly neutralized by the careful addition of 

 barium hydroxide until a faint permanent precipitate remained. 

 The solution was then allowed to stand over night. The substance 

 had then separated in the same crystal form as before. It was 

 filtered, washed free of chlorides with water and then in alcohol 

 and ether and allowed to dry in the air. 



The product was a heavy, crystalline, snow-white powder. Its 

 dilute nitric acid solution gave no reaction with ammonium molyb- 

 date. 



For analysis it was dried in vacuum over phosphorus pentoxide 

 at 105°. 



0.5772 gram subst. gave 0.0642 gram H 2 0. 



0.2124 gram subst. gave 0.0234 gram H 2 0. 



0.5130 gram subst. gave 0.0547 gram H 2 and 0.1180 gram C0 2 . 



0.1887 gram subst. gave 0.1348 gram BaS0 4 and 0.1098 gram 

 Mg 2 P 2 7 . 



Found: C = 6.27; H = 1.19; P = 16.22; Ba = 42.03; H 2 = 

 11.12 and 11.01 per ct. 



For heptabarium inosite hexaphosphate: 



(C 6 Hn0 2 4P 6 )2Ba7 or Ci 2 H 22 48 Pi2Ba7 = 2267. 



Calculated: C = 6.35; H = 0.97; P = 16.40; Ba = 42.39 per ct. 



For 16H 2 calculated = 11.27 per ct. 



preparation of the free acid. 



The acid was prepared from 5 grams of the first crystalline barium 

 salt in the usual way, i. e., the substance was suspended in water 

 and the barium removed by a slight excess of dilute sulphuric acid, 

 filtered and the filtrate precipitated with excess of copper acetate. 

 The copper precipitate was filtered, washed thoroughly in water, 

 suspended in water and the copper removed with hydrogen sulphide. 

 The filtrate was then evaporated to small bulk in vacuum at a tem- 

 perature of 40° to 45° and finally dried in vacuum over sulphuric 

 acid. There remained a practically colorless, thick syrup. The 



