118 president's address — SECTION B. 



ores of copper. The subject, though very young, is so very wide that 

 only a. brief recital of the principal events in the course of progress can 

 be given here. The purely chemical features can be almost wholly 

 passed over, since they are virtually identical with those of the Besse- 

 merising of matte, except for a few points incidental to the peculiarities 

 of mineral sulphides of iron, as also to the apparatus employed. The 

 latter is jyar excellence the blast furnace, though attempts to use the 

 Bessemer converter have not been uncommon. It is patent, however, 

 from the outset, that the proper aim of all smelting processes by 

 means of which ores are to be beneficiated should be sustained con- 

 tinuity of operation. The work should, if possible, be so done that 

 great tonnage capacity, coupled with an uninterrupted flow of products, 

 is achieved. Only under these conditions may it be hoped to utilise 

 to their utmost the various chemical energies involved, to minimise 

 losses of heat, and to reduce the formation of middle-products, tnd, 

 generally, to achieve the speediest and cleanest results, coupled with 

 the greatest economy of time, labor, and cost. The special points of 

 difference between the action of the blast furnace and the converter, 

 consequent on the difference in the relative disposition of the materials 

 reacting on each other, have already been referred to. In extension 

 it need only be said that, whereas an intermittent mode of operation, 

 such as that which is functionally characteristic of the converter- 

 vessel, may be tolerated, for want of something better, on material 

 as rich as mattes, it is out of place on material as low in value as the 

 ordinary run of copper ores. And that it can be avoided is clearly 

 proven by the best existing practice, the results of which even reflect 

 the possibility of radical improvements in our current converter 

 practice, as above contended. 



The pneumatic treatment of ores in blast furnaces, however, only 

 yields an unfinished product, i.e., the matte, which has to be (or may 

 be) further enriched and brought to blister copper in the converter 

 by a direct continuation of absolutely the same principle. Since the 

 metallurgical principle may thus be the same throughout, it may be 

 asked, why cut the operation in two— why not make the complete 

 transition from ore to metal in a single apparatus, be it blast-furnace 

 or converter ? Here, unfortunately, serious difficulties confront us. 

 We are still only en route to this very desirable simplification. It has 

 not yet been even partially achieved, notwithstanding that there has 

 been no lack of suggestions and trials. Even in the days before the 

 true pneumatic self-smelting notion arose attempts were made to 

 produce metallic copper direct in the blast-furnace out of sulphide ores 

 {e.g., Tessie du Motay, 1871), and the proposal has since been fairly 

 extensively ventilated and its execution essayed {e.g., Gamier, 1884 ; 

 C. M. Allen, 1893 ; Garretson, 1896, et al.), always with disastrous 

 results. What is being done in the newer employment of the so- 

 called basic-lined converter, above referred to (p. 95), is not identical 

 with these efforts, since the pyritic constituent, or, more properly, the 

 matte derived from same, is here prepared outside of the vessel in 

 which the charge is blown, and the operation is thus a twofold one. 



