Dr. F. H. Thomson's Historical Notes of Copper Smelting. 335 



and carbonates, containing a large proportion of silica, iron scales, in the 

 proportion of 2 to 3 cwts. per ton of charge. Sometimes also may 

 be used the native carbonates of iron, also scrap iron. 



His principal claim under these patents is the application of ii-on with 

 alkaline substances, and disintegration by water. 



I have described Mr. Napier's process as containing in its sub- 

 ject matter the substance of almost all the patented principles, viz., 

 the application of fusible siUcates in combination with iron and 

 carbon. 



A Mr. Law, in 1848, patents the application of a compound of 

 oxide of manganese, plumbago, nitrate of potash, nitrate of soda or lime, 

 and carbon. 



Another patentee, in 1849, claims the use of silicious and carbonaceous 

 matters, also dissulphurization without the use of iron or alkali. 



Mr. Parks of Birmingham, also in 1849, produced two elaborate 

 patents, which do not differ much in principle from those of his fellow- 

 labourers in this peciiUar field of science. 



He uses sulphuret of lime of soda, baryta, or potash, and holds that 

 a richer regulus is the result, and a more speedy metallic reduction pro- 

 duced than by any other process. 



Early in 1849, being impressed with the idea that the practical appli- 

 cation of a fusible silicate, easily procurable in a dense form, and con- 

 taining the chemical qualifications necessary in smelting a certain class 

 of ores, might be attainable, I instituted a set of experiments on such a 

 scale as would place me beyond the mere laboratory investigator. The 

 result was a patent specified by me on the 14th September, for the 

 application of whinstone as a flux, being a fusible silicate, including all 

 the varieties, such as trap, basalt, sienite, and the like. 



The claim was, the smelting of copper ores by the use of what is 

 commonly called whinstone, or other like stones, broken into fragments, 

 as a flux, or by the use of what is commonly called iron slag, all having 

 carbon added, and either with or without alkali as an improved flux. 



I might dilate at some length on the various phenomena elicited in 

 the course of my investigations, but feel I cannot do so with justice to 

 the time of the Society on this occasion. I may mention^ however, 

 that the results were beyond my expectation ; for with one roasting, one 

 melting of the matt, recalcination, and fusion, for tough copper, I got 

 metal of 99'80 of purity. 



These experiments were all eight or nine cwt., and many of them a 

 ton to the charge, and although much may be urged by smelters and 

 metallurgists in contravention of whinstone as a flux, in all cases of rich 

 ores there cannot be a doubt of its effect. The great objection is its 



