lOÔ 



DIVERS AND HAGA. 



The presence of hydro^-en, not merely as water of hydration, is shown 

 by first heating the salt for hours at 1<S0° in a current of dried air, and 

 then afterwards getting, at a nuich higher ftemperatu re, water vapixu- 

 condensed (containing sulphuric acid). As the salt is calculated to 

 yield only a little more than one-thousandth of its weight of hydrogen, 

 and the isolation of the water from all mercury would be difficult, 

 hydrogen was not quantitatively estimated. 

 The analytical results obtained were : — 



The preparation, (a), was made by the principal and direct 

 method. The other, (b)^ was digested with mercuric nitrate to remove 

 sodium which it at first contained, and then washed with water 

 slightly acidulated witli nitric acid. 



On writinof down the reaction bv which the salt under considéra- 

 tion is formed from mercuric nitrate and trisodium imidosul{>honate: — 



8Hg(N03),-l-Na3N(S(),)2-F20H2=HN(S03)2HgA+-^NaN03-i-8HNÜ3 



— and comparing it with the equation wliere oxymercuric sodium 

 imidosulphonate is the product, it will be seen that in both cases the ni- 

 trate comes out half as sodium nitrate and half as nitric acid, and that 

 the oxymercuric hydrogen salt may be represented as resulting from 

 the reaction of the sodium salt with mercuric nitrate, thus : — 



Hg(N03)2+NaN(S03)2Hg2() + OH2 = HN(SÜ3)2Hg302-hNaN03-|-HN03. 



