10 ART. n. — T. HAGA. 



in the same way as the sodium salt. The ammonium acid-sulphate 

 is got rid of by adding just enough barium hydroxide solution, 

 filtering, and evaporating, at first at a gentle heat and then in 

 the cold over sulphuric acid under reduced pressure. It occurs 

 as small thick plates, which are somewhat hard, and as nodules 

 composed of minute tabular crystals. It is a very soluble salt, 3 

 parts dissolving normally in just 2 parts of water at 18°, but it 

 is very apt to form suj^ersaturated solutions. It is a more stable 

 salt than the corresponding ;9,3-salt. Its crystals are probably 

 anhydrous, but those analysed showed the presence of 0.25 H2O 

 per molecule. 



.3559 gave .7189 barium sulphate. Sulphur = 27.74 



.2320 gave 35.5cc. moist nitrogen at 



16.2° and 754.5mm. nitrogen = 18.18 per cent. 



HAN3S2 requires sulphur, 28,21 ; nitrogen, 18.53. With iH.O 

 added, it requires sulphur, 27.66 ; nitrogen 18.17 per cent. 



Barium salts. — Barium salts have not been prepared in a 

 state suited for satisfactory determination of their nature. Evapor- 

 ation of a solution of the ammonium salt with excess of barium 

 hydroxide in a vacuum over sulphuric acid to a small volume removed 

 all ammonia. After removal of the excess of barium hydroxide by 

 carbon dioxide, the filtered solution was further evaporated in the 

 desiccator. First, a viscid liquid and then a bulky friable, porous 

 mass, devoid of crystalline character, were obtained. The latter 

 was not quantitatively analysed but it yielded, when hydrolysed, 

 barium sulphate aud hydroxylamine sulphate in cr^^stals which 

 were further identified by a very satisfactory sulphuric acid de- 

 termination. The product was therefore undoubtedly a barium 

 hydroxylamine-«^3-disulphonate. By using less barium hydroxide, 

 crystallised ammonium l)arium salts of varying composition may 



