54 PROCEEDINGS OF THE AMERICAN ACADEMY 



0.5582 gr. lost on ignition with WO^Na^ 0-10 1" gi% = 18.22% 

 0.7G67 gr. " " " 0.1393 gr. = 18.17% 



0.5329 gr. gave 0.0707 gr. (NHJ^O = 13.28% 



0.9753 gr. " 0.4501 gr. Yfi^ with KMnO^ = 46.15% 



O.G883gr. " 0,3174 gr. " " =46.13% 



0.1073 gr. " 0.0495 gr. " " =46.15% 



The analyses lead to the formula 



394.6 100.00 



I have here assumed that the simplest expression of the results of 

 the analyses represents the molecular weight. It will, I think, appear 

 from the study of other compounds, that it is at least probable that the 

 molecular weight is much higher. The solution of the salt is very 

 easily reduced by dust or traces of organic matter. The solution then 

 contains a greater or less proportion of a j^hospho-vanadico-vanadate. 

 The solution of the salt has a yellow color and a very strong acid 

 reaction, but this probably depends simply upon the decomposition 

 which sets phosphoric acid free. 



1 : 1 Arrientic Phospho-vanadate. — A quantity of the above-de- 

 scribed ammonium salt was dissolved with ammonic phosphate, and 

 argentic nitrate added to the solution in excess. A sulphur-yellow 

 crystalline precipitate was at once formed, which was digested with 

 very dilute nitric acid so as to remove argentic phosphate, and then 

 presented granular yellow crystals but slightly soluble in cold or hot 

 water. The salt is readily decomposed by dilute chlorhydric acid, and 

 then yields a yellow solution which is probably the acid of the series. 

 In the silver salt, 



1.4134 gr. gave 0.9192 gr. AgCl = 52.59% Ag,0 



1.6267 gr. " 0.7938 gr. metallic silver = 52.41% " 

 1.3696 gr. " 0.2851 gr. V„0, =20.82% 



1.0193 gr. lost on ignition 0.1067 gr. = 10.47% 



