MR. H. BAKER ON SOME THIONATES. 157 



XX. On some Thionates. By H. Baker, Student in the 

 Owens College. Communicated by Professor C. 



SCHORLEMMER, F.R.S. 



Bead October i6th, 1877. 



Having been lately working on these salts, I offer the 

 following observations : — 



Barium Dithionate, BaSiO^^aAq. — According to 

 Heeren* this salt is soluble in I'l part of boiling water ; 

 but he does not give the boiling-point of the saturated so- 

 lution ; this I have observed to be 102°, and its solubility 

 at this temperature to be i in 0*994 part of water. It is 

 remarkable that the saturated solution of such a soluble 

 salt should boil at so low a temperature. The sp. gr. of 

 the crystals of this salt at I3°'5 is 4*536. 



Lead Dithionate, PbSj06,4Aq. — " It is very easily so- 

 luble in water ^^ (Watts). I find its solubility at 20°*5 to 

 be I in 0-869 part of water. Its sp. gr. at 11° is 3*259. 



Calcium Dithionate , CaSi06,4x\q. — The crystals have a 

 sp. gr. of 2" 1 76 at 11°. 



Nickel Dithionate, NiSj06,6Aq. — One part of this salt 

 dissolves in 0*897 part of water at 12°. 



Magnesium Dithionate, MgSj06,6Aq. — According to 

 Watts's Dictionary, it " forms six-sided tables, very soluble 

 in water ; '^ but Gmelin says it forms ill-defined six-sided 

 prisms. 



I obtained it in oblique prisms, and found its solubility 

 at 17° to be I in 0'692 i)art of water. 



* fogg. Ann. vii. 172. 



