80 president's address — SECTION B. 



these older efforts have lost their interest. Its intense oxidising and 

 volatilising action guarantees the purity of the metallic product without, 

 at the same time, being violent enough to entail either an excessive 

 waste of copper or of the precious metals, when present. 



To return to the pneumatic process applied to mattes, it may be 

 remarked that the only other investigations of a kind similar to those 

 suggested by Semennikow, and carried out by von Josaa and Laletin, 

 which are recorded, were those of Stridsberg and Kollberg, in 1868, 

 at Westanfors, in Sweden. They were, however, only conducted on 

 a small scale, and not pursued far enough to yield any notable results. 



Chronologically the next significant event in the historical develop- 

 ment of our subject ushers in the extremely important subject of the 

 utilisation of sulphide ores as metallurgical fuels for their own igneous 

 concentration. The remarkable demonstration of the value of such 

 ores in this connection, which John Hollw;t,y's Penistone experiments 

 gave to an incredulous, at best only half-convinced, technical world, 

 took place in 1878-9. (n) Owing to the fact, however, that this tran- 

 sitional movement of the pneumatic principle from mattes to ores has 

 only recently fully established itself in actual practice — in the methods 

 of pyritic and pyrite smelting — and that the perfection of the process 

 of matte-conversion was approximated much sooner, we will not venture 

 on the discussion of the ore process, but further pursue the matte 

 aspect of our theme instead. The results of Hollway's researches 

 were nugatory, as far as their immediate translation into current practice 

 was concerned, and they had no influence on progress in the pneumatic 

 treatment of mattes, beyoiad, in a general way, again emphasizing the 

 feasibility of the rapid combustion of sulphide substances, while 

 complying with the usual metallurgical requirements of complete 

 fusion of the solid products, accompanied by increase of tenor and 

 readv mechanical separation of the waste from the valuable. 



Restitution of Pneumatic Process hy Manhes and David. — Tn the 

 more restricted and considerably more facile department of matte- 

 conversion the credit of having first surmounted the practical 

 difficulties standing in the way of the production of black or blister 

 copper belongs to the French industrialist, M. Pierre Manhes, of Lyons, 

 and his engineer, M. Paul David. Their first attempts were made 

 early in 1880, with a small bottom-blown converter vessel capable of 

 treating 200 kilos, on matte previously melted down in a crucible. 

 The usual phenomena of flame, volcanic ebullition, &c., accompanied 

 the trials. The slag thickened from overblowing, became impervious 

 to the blast, and was ejected in quantity. Metallic copper formed, 

 but was chilled by the blast, and the numerous vertical tuyeres were 

 choked by it. The mechanical difficulties thus encountered seemed 

 insuperable with the bottom-blown vessel. The first step towards a 

 partial cure, and an extremely simple one, but on which really hinged the 

 entire subsequent good fortune, was the elevation of the tuyeres from 

 bottom to side, and their insertion horizontally through the walls of 



(n) " A New Application of Bessemer's Process of Rapid Oxidation, in which 

 Sulphides are Utilised for Fuel," Journ. of Soc. Arts, Feb., 1879. 



