Dr. Muspratt on the Salts of Sulphurous Acid. 417 



quantity of it for analyses. It contains 33'68 per Q.ent. of 

 peroxide of iron. 



Sulphites of Nickel. — The two salts which I described in 

 my first paper on the sulphites possessed the subjoined for- 

 mulas : — 



NiO, SO2 + 4aq. 

 NiO, SO2 + 6aq. 



The latter agrees with the results of Fordos, Gelis and 

 Rammelsbei'g. I have again prepared the former by transmit- 

 ting a stream of sulphurous acid gas into water holding in sus- 

 pension carbonate of nickel. When the whole had dissolved, 

 the solution was filtered and boiled, which liberated a mass 

 of small greenish crystals, almost insoluble in water. 



6*02 grs. salt burned with chromate of lead gave 2*08 grs. 

 water = 34*55 per cent. 



The formula NiO, SO2 + 4 aq. affords 34-06 per cent, of 

 water. 



Dr. Bottinger has described a double sulphite of nickel of 

 the following constitution : — 



NiO, SO2 + NH^O, SO2 + 4 aq. 



Sulphites of Cadmium. — Carbonate of cadmium in water is 

 readily dissolved by sulphurous acid, and when the resulting 

 solution is treated with absolute alcohol an aluminous-looking 

 precipitate appears, which when dried and heated in a test- 

 tube afibrds no water — it must be the anhydrous sulphite of 

 cadmium. If however the gelatinous precipitate is allowed to 

 remain in the alcoholic menstruum for some days it disap- 

 pears, and there deposit in its stead beautiful silvery-looking 

 crystals, which turn out to be the same salt as that ob- 

 tained by Fordos and Gelis when dissolving the Vnetal in the 

 acid. 



Analysis: — 6-79 grs. of salt gave 6-94 grs. sulphate of ba- 

 rytes = l-90 sulphurous acid. 



8-11 grs. salt gave 1-29 grs. water. 



Centesimally represented,- 



Tlicorv. Found. 



27-98 



15-90 



1422-90 100-00 

 Formula, CdO, S02 + 2aq. 



It is oxidized very slowly when exposed to the air in a dry 

 state ; is sparingly soluble in water, and readily dissolved by 

 dilute acids. I have not formed any double salts with the sul- 



Phil. Marr. S. 3. Vol. 30. No. 203. June 1847. 2 F 



