IMIDOSULPHONATES. 1 1 1 



while it is usual to find it thus united at once to oxygen and to an 

 oxyo'enous radical. A third objection is that, whereas in other cases 

 sulphuryl takes one-andra-half atoms of mercuric oxide to saturate 

 either of its valencies, it does not do so in this salt unless the sodium 

 is oiven to one of the sulphuryls of the salt. The fourth objection lies 

 in the great improbability that sodium in the imidic relation would 

 resist, as it here does, displacement by hydrogen on contact of the salt 

 with nitric acid. Avoiding these four difficulties by placing one- 

 fourth of the mercury with the nitrogen, there remain .the usual 

 one-and-a-half atoms to unite with half one of the sulphuryls. The 

 relations of the salt, and its constitution as here developed, require 

 that its formula should be double that expresed in the lowest terms, in 

 order to allow of the oxylic mercury being shown apart from the non- 

 oxylic— Hg:(OHgO-SÜ2)2:N-Hg-N:(S03Na)2. 



It becomes now clear that the sodium resists the action of nitric 

 acid because it is in oxylic relation to sulphuryl, as pointed out in 

 discussing the constitution of the normal mercury disodium salt ; that 

 nitric acid removes a fourth of the mercury, replacing it by hydrogen, 

 because this fourth part is in relation to the nitrogen ; that nitric acid 

 does not remove the rest of the mercury l^ecause this exists as the oxy- 

 mercuric group found in oxylic relation with sulphuryl in sulphate 

 and sulphite, also then resisting the action of nitric acid ; and, lastly, 

 it becomes clear how it is that the oxymerciiric hydrogen imidosul- 

 phonate has quite consistently a constitution different from that of the 

 oxymercuric sodium salt, and how the one salt is formed from the 

 other. (Cf. Divers and ShimidzAi on Mercurij Sulphites, J. Coll. Sei. 

 1, 101). 



In fact, the constitution of the oxymercuric hydrogen imidosul- 

 phonate follows obviously from the production of the salt by (acid) 

 mercuric nitrate in excels. From what we actually can observe in thç 



