1824.] certain Compounds of Sulphur. 447 



acid ; but this would be sufficient only to saturate either 48 

 of potash = 1 atom, or 52 of protoxide of antimony = I atom. 

 This is a difficulty ; but as a double salt is evidently formed, may 

 we not suppose that the metallic oxides, oxide of potassium, and 

 oxide of antimony, form sub-bisalts with the sulphuretted hydra- 

 gen ? or so to speak, that they each take half an atom ? We 

 should then have a salt consisting of 



"6 



1 atom hydrosulphuric acid = 17 



1 atom potash = 48 



1 atom oxide of antimony = 52 



It can hardly be admitted that more than one atom of water 

 is decomposed ; for in that case we should increase the difficulty; 

 since not only would there be 2 atoms of hydrogen to combine 

 with 1 of sulphur ; but either hyposulphurous acid, or peroxide 

 of antimony, must be formed at the same time: now for the 

 former the sulphur is evidently insufficient, and peroxides lose 

 oxygen by exposure to the action of hydrosulphuric acid. 



The action of hydrosulphuric acid upon metallic oxides is 

 reducible also to three cases. First, when they combine without 

 either being decomposed, as when potash unites with it to form 

 an hydrosulphate. In this case neither the hydrosulphuric acid 

 yields its hydrogen, nor does the oxide give up its oxygen. The 

 same appears to be the case with oxide of antimony, excepting 

 that the compound is insoluble in water. The second case is 

 when the hydrosulphuric acid is decomposed, but without pre- 

 cipitating the metal from solution. This happens when sulphu- 

 retted hydrogen is passed into a solution of peroxide of iron. 

 The excess of oxygen combines with the hydrogen of the hydro- 

 sulphuric acid, the peroxide becomes protoxide, and sulphur is 

 precipitated. The third case is that of adding hydrosulphuric 

 acid to solution of lead, copper, &c. In these cases water 

 appears to be formed by the union of the hvdrogen of the hydro- 

 sulphuric acid, with the oxygen of the metallic oxide, and the 

 consequence is that a metallic sulphuret is precipitated. 



These hypothetical ideas are thrown out in the hope that they 

 may lead to experiments for the purpose of elucidating an 

 important but yet obscure branch of chemical science ; and it 

 may be observed, if these speculations are just, that the disco- 

 very of hyposulphurous acid is one of considerable importance in 

 elucidating this subject. 



