470 Macfarlane on the Aeton Copper Mine, 



A sample of ragging gave : — 



Silicious matter 16.92 



Carbonate of lime 53. 0*7 



Carbonate of magnesia ..•••• . . trace 



Iron 4.06 



Copper 13.07 



Sulphur 11.62 by difference* 



100.00. 



A sample of butch-work gave : — 



Silicious matter 24.32 



Carbonate of lime 53.10 



Carbonate of magnesia 2.10 



Iron. 3.36 



Copper 9.95 



Sulphur 7.17 by difference. 



100.00 



From these results, and from others previously given, it will ap- 

 pear that silica and lime are almost the only slag-producing ma- 

 terials contamed in these ores. Iron is present in small quantity, 

 but without previous calcining, which in this case is inadmissible, it 

 would go to the formation of the regulus. The compounds of 

 silica with lime are all but infusible ; but these substances form 

 with iron oxide, easily fusible slags, which are frequently produced 

 iu copper-smelting works. In smelting the Acton ores, therefore, 

 a flux containing iron oxide, such as puddling slag, or roasted iron 

 pyrites, is indispensable. The cost of these would not add very 

 materially to the expense of smelting ; but it would of course be 

 better, if such could be had in the neighborhood, to use in place 

 of these fluxes, poor pyritous copper ores, previously calcined. 



The total product of the Acton Mine during the period to 

 which this paper has reference, viz., from September 1st, 1861, to 

 September 30th, 1862, was 2336 tons of 2,352 lbs. ; or 2,747 tons 

 of 2,000 lbs, the average copper contents of which amounted to 

 12.0 per cent. This is equal to an average monthly production 

 of 179 tons of ore of 2,352 lbs., or 211 tons of 2,000 lbs. In reality, 

 however, the production was much greater in the summer than the 



