352 PROCEEDINGS OF THE AMERICAN ACADEMY 



since the properties of the neutral salt were unfavorable to purifica- 

 tion, it was converted into the acid salt, and this recrystallized from 

 hot water. The acid salt was readily soluble in hot water, more spar- 

 ingly soluble in cold water and crystallized in triclinic (?) prisms which 

 effloresced on exposure to the air. It gave an excellent qualitative 

 reaction for sulphur, and when dried over sulphuric acid* gave the 

 percentage of barium required by the formula Ba(C.HCl 2 SO c ) 2 . 



0.3886 grm. of the salt dried over sulphuric acid gave 0.1338 grm. 

 BaS0 4 . 



Calculated for 

 Ba(C 5 HCl 2 S0 6 ) 2 . Found. 



Ba 20.84 20.24 



Baric x Dichlorsulphopyromucate, BaC 5 Cl 2 S0 6 . 2 H 2 0. — From the 

 acid barium salt we prepared the neutral salt by neutralizing its aque- 

 ous solution with baric carbonate. Since the hot saturated solution 

 deposited little or nothing on cooling, it was evaporated in vacuo over 

 sulphuric acid. The salt then crystallized in sheaves of prisms which 

 appeared to be triclinic. It was permanent in the air, effloresced over 

 6ulphuric acid, and lost its water completely at 160°. 



1.4159 grm. of the air-dried salt lost at 160° 0.1277 grm. H 2 0. 



Calculated for 

 BaC 5 Cl 2 S0 6 . 2 H 2 0. Found. 



H 2 8.33 9.02 



0.5296 grm. of the salt dried at 160° gave 0.3126 grm. BaS0 4 . 



Calculated for 

 BaC 5 Cl 2 S0 6 . Found. 



Ba 34.59 34.69 



The formation of a dichlorsulphopyromucic acid by the action of 

 fuming sulphuric acid upon the x dichlorpyromucic acid is thus suffi- 

 ciently established. The bromsulphop3Tomucic acids are so readily 

 reduced in alkaline solution that we hoped to be able to prepare from 

 this dichlorsulphopyromucic acid the corresponding sulphopyromucic 

 acid, and thus establish the position of the two chlorine atoms. We 

 soon found, however, that the chlorine was held with unusual persist- 

 ence, and with the material at our disposal we have as yet been unable 

 to reach decisive results. 



* The single determination of the water of crystallization was unfortunately 

 defective. It gave 13.34 per cent of water in the salt dried by short exposure 

 to the air, while a salt crystallizing with 2£ molecules of water should contain 

 13.70 per cent. 



