COLLECTIONS IN ECONOMIC GEOLOGY AND METALLUKGY. 



71 



Final products. 



The second series of Hue dusts shows the finished white i)aint, col- 

 lected after passing tliroagii the fire. This operation oxidizes tlit; sul- 

 phides to sulphates, so that tlie final product is a mixture of suli)hates, 

 carbonates, and oxides of lead and ziuc. 



(1) From middle of cooling pipes. (55185.) 

 ' (2) From first cooliug chamber. (55183.) 



(3) From second cooling chamber. (55184.) 



(4) From exhanst fan box. (55186.) 



(5) From lirst hopper, first row; good quality. (55187.) 

 (fi) From fifth hopper, first row; medium quality. (55188.) 

 (7) From ninth hopper, third row ; best quality. (55189.) 

 On analysis by the writer two samples yielded : 



I 



Sulphate of leacKPbSOj) 



Oxide of lead (PbO) 



Oxide of zinc (ZuO) 



Sesqiiioxide of irou aud alumina ((FeAb^Os) 



Linio (CaO) 



.Silica (SiOj) 



Carbonic acid (COj) 



Sulphurous acid (SOj) 



Water (H^O) 



55189 



Byjii'oducts. 



(1) Slag. (55178.) 



Analyzed by the writer it showed: 



Per cent. 



Silica (SiOi) 42.10 



Oxide of lead (PbO) ^5.37 



Protoxide of iron (FeO) 7.91 



Alum ina ( AljO:,) 9. 58 



Nickel and Cobalt (Ni and Co) traces 



Oxide of manganese (MnO) 0.27 



Oxide of zinc (ZnO) 4.48 



Lime (CaO) 7,97 



Magnesia (MgO) 1.60 



Sulphur (S) 0.22 



99. 56 



(2) Basic carbonate of lead, solid deposit from the bottom of the flue. (55181.) 

 On analysis by the writer it showed : 



Residtie. 



Per cent. Per cent. 



Silica (SiO,^ 2. .57 



Sulphate of lead (PbS04) 1.05 



Se,s(iuioxide of Iron (Fe^Ot) 0. 80 



Alumina (ALO^) : ■ 0.63 



Oxide of ziuc (ZuO) 1.19 6.24 



