1 74 Dr. Kolbe's Contributions to the 



tating the alcoholic solution of the potash salt with sulphuric 

 acid. The filtered acid solution may be evaporated, and the 

 excess of sulphuric acid precipitated either by carbonate of 

 lead or baryta water. The hydrate of the hyposulphate of 

 chloride of formyle forms a thick liquid, which crystallizes, 

 in vacuo over sulphuric acid, in small scales, and is similar 

 both in its stability and power of combination to the hypo- 

 sulphate of chloride of carbon. The silver salt, Ag O + 

 Cg HClo, S2 O5, is very sensitive both to light and heat; it 

 can only be obtained in a crystallized state in a vacuum and 

 in the dark ; when dry it will bear a temperature of 100° C. 

 without change. 



Hyposulphate of chlor-elayle, HO-i-SCgHg CI, 85 O5, con- 

 tains chloride of elayle as a conjunct, or another isomeric com- 

 pound. It is formed by the substitution of two equivalents of 

 hydrogen for two equivalents of chlorine of the hyposulphate 

 of chloride of carbon, when a solution of hyposulphate of chlo- 

 ride of carbon and potash is acidified by sulphuric acid, and 

 decomposed by a galvanic current. Two pairs of the Bun- 

 sen carbon and zinc series are required for it ; two amalga- 

 mated zinc plates were the electrodes. 



The average power of the current, as measured by Weber's 

 galvanometer, was 82°, equal to a deflection of the needle of 

 55°. The hydrogen in the nascent state unites with the chlo- 

 rine of the hyposulphate of chloride of carbon at the cathode, 

 and forms muriatic acid ; the equivalents of chlorine are sub- 

 stituted by equivalents of hydrogen. This exchange only pro- 

 ceeds in the formation of the hyposulphate of chlor-elayle, as 

 long as the fluid which is to be decomposed contains an ex- 

 cess of acid, 



KO + C2 CI3 S2 O, r^^^+ ^2 H, CI, S, O5 



*^^ I2O. 



The oxygen is not set free by the above decomposition, but 

 unites with the zinc of the anode; but if the fluid is so far sa- 

 turated with sulphate of zinc, that the reduced zinc is deposited 

 on the cathode, then it must be precipitated with carbonate of 

 potash, and the filtered fluid being again rendered acid, must 

 be once more exposed to decomposition by the current. 

 This operation is to be repeated as long as traces of chloro- 

 hyposulphate of formyle are perceived, whicli will be known 

 when the potash salt of the hyposulphate of chlor-elayle, to be 

 extracted out of the fluid precipitated by carbonate of potash 

 and evaporated to dryness, gives out muriatic acid at a red 

 heat. It is impossible to separate both the salts when they 

 occur mixed. 



