6 ART. 15— TAMEMASA HAGA. 



Lossen (Ber., 1892, 25, 440) has already pointed out that dibenhydr- 

 oxamic acid may be regarded as the mixed anhydride of benzhydrox- 

 amic acid and benzoic acid, and similarly in the case of other diacyl- 

 hydroxy lamines»* Nitrososulphuric acid (nitrosyl hydrogen sulphate), 

 the mixed anhydride of nitrous and sulphuric acids, is an example 

 of a mixed inorganic anhydride. But the present salt, as the an- 

 hydride of two different acid salts, finds its close analogue in 

 potassium hyponitrososulphate, (S0 3 K)0(N 2 OK) (Pelouze's 'nitrosul- 

 phate,' Journ. Chem. Soc, Trans., 1885, 47, 203, this Journal, 9, 

 101, 277) which is the anhydride of acid hyponitrite and acid 

 sulphate. The two mixed anhydrides agree in being stable in alkaline 

 solution and unstable in acid solution, and in not giving barium 

 sulphate with barium hydroxide or chloride. 



The evidence that the metasulphazilates have the constitution of 

 hydroxylaminetrisulphonates is simple and direct, and similar to that 

 as to the constitution of the hyponitrososulphates. In the first place, 

 sodium amalgam decomposes them, apparently quantitatively (p. 26), 

 into sulphate and normal aminedisulphonate (iminosulphate): — 

 KO-S0 2 -0-N(S0 3 K) 2 + 2Ka=KO-S0 2 -ONa+NaN(S0 3 K) 2 , 

 no sulphite being formed. Instead of sodium amalgam, the zinc- 

 copper couple may be used with the boiling solution to reduce 

 hydroxylaminetrisulphonates (p. 28), but in this case the aminedisul- 

 phonate is apt to hydrolyse during the heating. The result of this 

 reduction of the salts not only proves their sulphatic constitution but 

 shows also that neither the formula, ON(S0 3 K) 2 (Claus, Hantzsch), 

 nor this formula doubled (Raschig) can possibly be right, because its 



* Twenty-six years ago, Koenigs (Ber., 1878, \\, 015 and 1588) found that benzenesulphinic 

 and nitrous acids react to form hydroxylaminedibenzsulphinic (dibenzsulphydrosauiie) acid, and 

 that this with more nitrous acid becomes a triberizsulphinic compound. Preliminary experi- 

 ments made for the author seem to show that the latter will almost certainly prove to be 

 hydroxylaminetribenzsulphinic acid. Its production may probable be expressed by the following 

 equation : — 



GC 6 H 5 S0 2 H + 4H0X0 = 2(C 6 H fi S0 2 ) 2 S-0(S0 2 C 6 H 8 ) + N 2 + 5H 2 0. 



