122 president's address — section b. 



nature, the method, essentially, beint; adapted to blast-furnace work- 

 As stated above, he limited it to the production of rich regulus, though 

 the possibility of producing metallic copper occurred to him. The 

 gases were, of course, to be utilised for the manufacture of sulphuric 

 acid, and the elemental sulphur, which sublimed off as the loosely 

 bound atom in the pyrites, was also to be caught. This point was 

 considered as more essential than it really deserved. In a subsequent 

 attempt to repeat the operation in a small blast-furnace somewhat 

 resembling a stationary Swedish converter, the loose sulphur atom 

 very deplorably became the ruin of the entire scheme. It choked up 

 the condensation flues, thus creating a back-pressure which caused the 

 furnace to break out, after which, as in Parry's case (p. 66), no further 

 repetition was forthcoming, the financial supporters probably becoming 

 disheartened. In consequence, the idea languished and became the 

 butt of professional ridicule and satire. The conservatism of English 

 copper-smelters militated against its further prosecution and perfection, 

 and conditions elsewhere were not ripe for it. 



Intellectually, however, a most useful seed had been sown. Never 

 before had any set of practical demonstrations outside of iron and 

 steel been conducted with the convincing force of equal magnitude 

 and impressiveness. Then, in addition, Mr. HoUway had supported 

 his essay on the subject by an interesting thermal calculation of the 

 temperatures generated in the oxidation of iron pyrites (and other 

 sulphides) in the presence of silica, which had a special academic con- 

 clusiveness, particularly as it was supplemented by a parallel one by 

 Professor Akerman. A simplified statement of the problem was em- 

 bodied in one of Professor Balling's text-books in 1882 (u). These 

 early thermo-chemical proofs left no doubt as to the feasibility of the 

 general pyritic idea. It only remained to so conduct the practical 

 management of any particular instance of its application as to conform 

 to the ordinary mechanical or physical desiderata of smelting pro- 

 cesses, such as continuity of flow of molten products, ready separation 

 by differences of specific gravity, &c. In the case of pyritous copper 

 ores the proposition in these respects appeared comparatively simple, 

 and the incidental causes of Mr. HoUway's apparent lack of success 

 were not insuperable. 



Thus we find the rapid oxidation theory at last brought to a certain 

 amount of practical prominence in the treatment of sulphide copper 

 ores. Moreover, the Bessemer smelting of ore gained in desirability 

 all the more with the contemporaneous permanent establishment of 

 the Bessemer converting of copper mattes. It became a metallurgical 

 aim to treat both ores and mattes by the same method. But there 

 were still serious difficulties. Unfortunately, the fascinating idea of 

 utilising the two most abundant mineral substances in the earth's 

 crust, i.e., silica and pyrites, in igneous chemical play, with such startling 

 economical results, was greatly hampered by the comparative scarcity 

 of the second-mentioned mineral in larger ore deposits, and hence few 



(m) C. a. M. Balling, " Compend. der Metallurg. Chemie.," Bonn, 1882. 



