Dr. F. H. Thomson's Historical Notes of Copper Smelting. 333 



scientific than the other — and all supposed to be improvements on the 

 old system. The race began about the year 1828, shortly after the 

 first importations of foreign ore, by a Mr. Brunton of London. 



He is followed, on the 17th of July, by a Mi'. Jones of Anglesea, who 

 patents a new process for the reduction of copper ores. In 1830 only 

 one patent was taken out ; the same in 1832 ; in 1835, two ; in 1838, 

 three ; and in 1839 the plot thickens, — five different patentees tried their 

 luck. But to do more than merely hint at these early attempts of ap- 

 plied science, however interesting historically, would be needless, and I 

 shall therefore only review a few of the most practical amongst the sixty 

 or seventy included in the patent records. 



The first containing matter of any importance was a patent taken 

 out by our respected townsman, Mr. James Napier, for the purpose of 

 smelting copper by electricity. 



He commenced by roasting the sulphuretted ore as usual, then fused 

 it in a reverberatory furnace, having a black-lead hearth, and caused a 

 very powerful current of electricity to traverse the fused mass, con- 

 ducted by the hearth and a plate of cast iron kept on the surface of 

 the melted metal. The apparent result was, the separation of metallic 

 copper from the fused ore. 



Having got certain definite results, a doubt arose as to the true cause 

 of this separation, and a set of experiments were instituted simultane- 

 ously by Mr. Napier and Messrs. Eivot & Philips, who ascertained 

 that although a voltaic current furnished by thirty elements of a Bun- 

 sen battery seemed to exercise an indubitable decomposing action on 

 the copper ore, and separated copper in a metallic state, yet the coal of 

 the graphite hearth, and the plate of cast iron employed as a pole, were 

 alone capable, without the aid of electricity, to produce the same 

 effect 



Messrs. Rivot and Philips were led by these results — seeing that in 

 the ordinary process, consisting of a series of roastings and successive 

 castings, much fuel was lost, and also much copper carried off, if not 

 conducted with great care — to attempt a process for the reduction of 

 copper by one roasting and one melting. 



They submitted the ores to a roasting sufficiently complete to dis- 

 sulphurize and transform the iron and copper into oxides, then added 

 reducing substances, which would produce a slag somewhat of the com- 

 position of a bisilicate of the protoxide of iron and lime, and in addition 

 a certain quantity of charcoal, or coal in small pieces, so that the oxygen 

 in the ore might transform the carbon thus added, — one half into car- 

 bonic acid and the other into carbonic oxide. 



When at the melting point the carbonaceous matter separated a large 



