IMIDOSÜLPHONATES. 79 



no well-detined Ibrins. The decanted mother-liquor evaporuted a 

 little gives more of the granules, but no crystals of sodium or potas- 

 sium nitrate. The granular mass drained and pressed on a tile has a 

 composition closely approaching that of one molecule of dipotassium 

 imidosLiIphonate to one of nitrate, the nitrate being of potassium and 

 sodium in single atomic proportions, NaN'03,KN03, 2HN(S03K)o. It 

 is decomposed by water, and is anhydrous. 



Sodium 

 Potassium 

 Sulphur 

 Hydrogen nitrate 



The two potassium salts or the two sodium salts do not form 

 double salts together. Disodium imido.sulj^honate and potassium 

 nitrate suffer double decomposition. The formula of the salt just 

 described shows also that, to some extent, this double decomposition 

 is reversible. 



In oiu- next connnunication we shall have to describe still more 

 remarkable combinations of nitrates with oximidosulphonates. 



Bariwii imidosulplionates, simple and double. 



Barium imidosidphonate. — This salt has been prepared by Berglund, 

 but no particulars of it have been published, except possil)ly in 

 Swedish. It is obtained as a, voluminous, coherent precipitate when 

 trisodium imidosulphonate is added gradually to good excess of 

 barium chloride. Drained on the porous tile, after thorough washing, 

 it is still very bulky, and hangs togetlier in soft flocks, more like 

 some organic salt than an inorganic barium salt. It retains moisture 

 in the interstices (jf its matted texture with remarkable obstinacy, so 



