V. MANUFACTURES. 649 



2726. No. 3. Mixture of Burnt Ore and Salt (the latter 

 being about 12 per cent, of the whole), ground and passed through 

 sieve of about 16 holes per square inch. 



Widnes Metal Company. 



This mixture is furuaced during a period of 5| hours, at the expiration of 

 which time the copper has usually been almost entirely converted into a 

 soluble chloride of that metal. 



2727. No. 4. Mixture of Salt and Burnt Ore after calcina- 

 tion during 5J hours. Widnes Metal Company. 



2728. No. 5. Purple Ore, or residue left from No. 4 after 

 the extraction of the copper by Kxiviation with hot water and 

 dilute hydrochloric acid. Widnes Metal Company. 



This residue is chiefly employed for the " fettling " of puddling furnaces. 



Ferric oxide - - 96 



Lead 



Copper 



Cobalt 



Alumina 



Lime 



Soda 



Phosphoric anhydride 



Arsenic 



Sulphuric anhydride 



Sulphur 



Chlorine 



Silica 



100-15 



2729. No. 6. Purple Ore compressed into blocks for use in 

 the blast furnaces (the brick exhibited was made by Messrs. N. 

 Mathieson & Co., of Widnes). Widnes Metal Company. 



2730. No. 7. Solution of Copper as drawn from the lixivia- 

 tors, containing, in addition to copper, &c., from three to four 

 grains of silver per gallon, with traces of gold. 



A quantity of iodide of potassium (or zinc) sufficient to precipi- 

 tate the silver present is added to this solution, and the precipitate 

 formed is allowed to subside, the supernatant liquor being passed 

 into vessels in which the copper is precipitated by means of metallic 

 iron. 



Widnes Metal Company. 



