84 president's address — section b. 



copper scrap, brass, old bronze, &c., was treated, either by itself or 

 together with matte, (p) Zinc, tin, lead, &c., oxidised easily, a small 

 dose of spiegeleisen, or manganiferous pig iron, being added to liquefy 

 the slag. M. Manhes was partial to this metallurgical laxative. Before 

 turning to the pneumatic methods, he had invented the alloy cupro- 

 manganese, which was used at the end of the ordinary refining process, 

 or at the moment of ladling, and was a substitute for the charcoal, 

 lead, or sulphur commonly employed. 



In addition to thus setting the copper-converting process tlioroughly 

 on its feet, Manh-^s was also the first to treat nickel mattes in the con- 

 verter (1883-4), enriching 16 per cent, matte to 70 per cent, nickel by 

 15 minutes' blowing. Much more than this is not accomplished to this 

 dav, owin •: to the equivocal behaviour of nickel in relation to sulphur 

 and ox3^gen. 



The Manhes practice was covered by a number of patents Avhich 

 mark the progressive steps of the invention in point of time, and, though 

 outside of the proper scope of this paper, may be briefly referred to in 

 consequence of the adverse fate of the most important ones in the 

 United States of America, where the method has found its principal 

 home. Th"? original French patent is dated May 26th, 1880, and claimed 

 the general features of the process and the use of the Bessemer converter 

 for the purpose. A few days later followed the refining scheme above 

 mentioned. A specification of October 23rd, 1880, covers the use of 

 manganese, silicon, and phosphorus. The horizontal tuyeres were 

 patented on Februaiy 9th, 1881, and, while it may be freely conceded 

 that they were the first step towards a rational mechanical solution of 

 a very prominent difficulty, the idea, though original with M. Paul 

 David, has a clear precedent in Bessemei's steel converter of 1862. 

 This was a pear-shaped vessel having a re-entrant shoulder at the 

 bottom, the ledge of which is occupied by an encircling wind box, 

 from which, radially placed, horizontal tuyeres issue through the lining 

 into the interior of the apparatus at a fair elevation above the bottom 

 of the cavity. David arranged the construction so that thin rods of 

 iron could be driven into the tuyeres through openings in the cover of 

 the wind box, or " air belt," for the purpose of clearing the tuyeres 

 for the free passage of the blast, (q). This " punching " is a most 

 necessary performance, since during a great part of a blow the tuyere 

 orifices are constantly choking up, even with the most skillful manipula- 

 tion of the vessel. The apparently exceedingly trivial matter of placing 

 the lateral tuyeres and the holes in the " air-belt " in such a position 

 that punching was feasible, as well as this commonplace manoeuvre 

 itself, later on assumed a most formidable financial importance in con- 

 nection with the American patents. Legally boiled down to their 

 concretest individual essence, the patent claims here were estimated 



(p) Revived by Schwietzke, " Bessemerising of Zinc, Lead, Tin, and Copper Refuse," 



Mctallurgie, 1906, vol. III., No. 20. 



{q) Bessemer naturally also had openings, closed with screw caps, in the face of 



the ait-channel, for access to the tuyere bricks. Journal of Iron and Steel 



^.nst, II., '1886, p. 645. 



