46 EOYAL SOCIETY OF CANADA 



fulfilled if dilute ammonia is stirred with Bi^O^ 2 C^O^H^O and there- 

 fore a divariant system still contains but one solid phase. Preliminary 

 experiments showed that the new basic salt obtained in this way was 

 acted on by quite dilute ammonia and in order to get this solid phase 

 in equilibrium with a larger range of concentrations of ammonia, it 

 was necessary to reduce the efficiency of the ammonia in the reaction. 

 This can be done by adding to the solution any ammonium salt, thus 

 decreasing the amount of ionization and as ammonium oxalate is one 

 of the products of the reaction it is the best salt for the purpose. 



At 75°, Bi^O^ 2 C^O^H^O was stirred with .038 normal ammonium 

 oxalate and ammonia of varying concentrations and a new basic salt, 



in which J^^^ = 9-69, was found to be in equilibrium with ammonia 

 G2C/3 



solutions up to .115 normal. This salt when air-dried had the following 



composition : — 



When Bi.yO^ 2 C^O^H^O was stirred with stronger ammonia or 

 potassium hydroxide, bismuth oxide was formed and there was no 

 indication of the formation of another basic oxalate. 



Souchay and Lensson have described the following double oxalates 

 Bi^ {C^OJ^ 7 K^C^O^ 34 H^O, Bi^ (C^O^)^ 11 K^C^O^ 34 H^O and 

 BU (0,0^), 15 (NH,), CM, 34 H^O. 



They dissolved bismuth oxalate in concentrated hot solutions of 

 the alkaline oxalates and the double salts crystallized on cooling the 

 solutions. Eesults obtained by stirring bismuth oxalate with ammonium 

 oxalate and with potassium oxalate threw doubt on the existence of 

 these complex double salts and Souchay and Lensson's experiments 

 have been repeated and the salts obtained were analyzed by Messrs. 

 DeLury and Phillips. 



A 4 per cent solution of ammonium oxalate was boUed with 

 bismuth oxalate, using a reflux condensor, for half an hour, filtered 

 hot, and the microscopic crystals formed on cooling were dried, under 

 pressure, between paper. The ammonia was determined by boiling 

 with potash and titrating the solution which distilled over. 



BL 



