g4 E. DIVEES AND T. HAGA. 



ceeding ;i.s for tlie last described salt", but taking" to two mois, of the 

 potassiiiin salt only one niol. of the lead salt, the clear solution 

 obtained after agitating- to dissolve the precipitate first formed, yielded 

 us when stirred with a glass rod a sandy crystalline precipitate of tlie 

 composition expressed by either of tlie above formula', but with nearly 

 ^6" of the potassium replaced by hydrogen, as tlie calculation sIkjws : — 



Calc. Found. 



Lead ;^3-51 3o-46 



Potassium 1.S-Ü8 IS'oo 



Sidphur 15'54 lo'Si^ 



The mother-liquor proved to be free from lead and [»ractically neutral. 

 The following equation ex[)resses, therefore, the reaction which had 

 taken place: — 



4K5H(XS20,), + 1^ 1 •b(OÄc), + H,() = U Pb,K,H(NS,U,X+ iKOAc 

 + 5lv,HX\S,07. 



From/ s .s(///.— -Almost in the same way, that is, by adding 

 normal lead acetate drop by dro]) to warm concentrated solution of 

 the Ks «idt, agitating to dissolve the immediate precipitate, and going 

 on until suddenly a second crystalline precipitate ajjpeared. Fremy 

 got a salt liaving nearly the same content of sulphur as our salt just 

 described, Init with more lead and less potassium, which admits of no 

 simple representation by a f )rmidî), although there are, closely enough, 

 4K to iPb. We give the calculation for P1jK,(NS2Ü:),,, along wdth 

 Fremy's finding : — 



Calc. Found. 



(Fremy) 



Lead i>7-85 28-40 



Potassium 1^-04 1^-44 



Sulphur 17"2'2 lo'Go 



Xitrouen 3'77 3*48 



