president's address — SECTION B. 85 



to enshrine only these two practical points as actual novelties, all the 

 other chemical and metallurgical features of the whole brilliant idea 

 ■falling like empty pods by the side of these paltry kernels, both in their 

 passage through the patent office and through subsequent long-con- 

 tinued litigation instituted for the reclamation of royalties in America. 

 Developments in this connection were eagerly watched by interested 

 circles, and mechanical evasions and subterfuges resorted to in new 

 installations, both in Europe and America, occasionally incompre- 

 hensible to the outsider on account of their circumlocutory incon- 

 venience. Ultimately, in 1902, the whole question terminated adversely 

 to the inventor, the court, while giving full honor to the patentees for 

 the great service rendered to metallurgy by the process as a whole, 

 calling in Cjuestion the intelligence of the patent- office in granting 

 protection to features as hackneyed as the tAvo points referred to. 



Features of French Practice : Horizontal Vessel. — As intimated, 

 certain parts of the operation remained a long time less understood, 

 or, at all events, less attended to, in France, so that it became the 

 established custom there to blow the same matte twice, wath a melting 

 going before each blow. The vessels remained of small size, and hence 

 all disturbing influences were accentuated by the diminutive quantities 

 of matte treated, increasing, so to say, in the inverse ratio of the super- 

 ficial size cf the converter, or rather of the extent of its receptive 

 capacity. Irregular yields of copper induced by variable grades of 

 matte, which caused the white metal and copper to stand at varying 

 levels Avith respect to the fixed one of the tuyeres, induced M. David 

 to abandon the conventional upright form of converter in 1883, and to 

 invent the recumbent, horizontal form so much in favor at the present 

 time. It was patented in France in December of that year, but did 

 not come into use outside of that country until 1893. Like its pre- 

 decessors in the mechanical adaptation of the idea to the requirements 

 of actual work, it is also eclectic. It is about the only construction 

 which Bessemer did not elaborate, probably deterred by its defects ; but 

 Nystrom, in 1862, had designed a similar converter for steel, and there 

 Avere also the Danks and oth^r rotary puddling furnaces. Like the 

 latter, the converter — now a simple cylinder with two flat ends, and 

 the usual nose in the centre of the length— was placed horizontally on 

 rollers, and rotated on these by side-gearing, instead of in trunnions, 

 as in the tiltable, upright tj'pe. This departure gave an opportunity, 

 not afforded by the older construction, of realising the maintenance of 

 the position of all the tuyere openings in the same horizontal line, no 

 matter at what level this line stood with respect to the contents of the 

 vessel. The alignment of the tuyeres is on an element of the cjdinder 

 forming the vessel, so that, with the rotation of the latter about its axis, 

 all the tuyeres enter the bath collectively, at any desired level of same. 

 This is not the case with the upright shape, where the tuyeres all occupy 

 the same level, relatively to the bath, only when the latter is in its 

 normal upright position, and the depth of entrance of the blast varies 

 among the battery of tuyeres when the vessel is tilted. The new con- 

 struction permits of dipping the tuyeres collectively into the bath to 



