president's address SECTION B. • 87 



operations were keenly watclied in copper circles — especially by the 

 company's neighbors in the same locality. In the patent office the 

 process appears to have had a difficult pilgrimage to make, for though, 

 as remarked, the application was made in 1883, the first letters patent 

 were not issued until 1892. 



Operations during the first couple of years at Butte (r) remained 

 under the tutelage of the French home method of procedure, the mattes 

 being kept at about 35 per cent, copper and the blowing divided into 

 two distinct operations, the slag and the white metal being poured 

 together after the first blow, and the latter lemelted for the second. 

 It was held that, even under the very much wider manipulative scope 

 which Butte conditions offered, it was impossible to blow to copper 

 without an inteimediate discharge of the enriched matte. The keener 

 practical sense of the local metallm'gists in charge, however, was not 

 long in emancipating itself. By 1885-6 the greater suitability of a 

 50 per cent, matte for a single vessel blow to copper, the possibility of 

 pouring or skimming the slag separately when white metal was j cached, 

 and the feasibility of at once blowing the lacter to a finish without 

 additional heat from remeMng, Avere all points promptly taken note 

 of by them. The introduction of these important improvements is 

 due to A. J. Schumacher, who also greatly perfected many of the detail 

 mechanical features in the construction of the vessels, their movement, 

 handling, lining, &c. By the years mentioned it may be said that the 

 process, on its manipulative side, was matured for a life on a vaster 

 scale, and what further growth it has since sustained is due to the rest- 

 less activity of many similar minds characteristic of its new home, to 

 which the method of to-day is always merely an omen of something 

 better for to-morrow. Curiously enough, it appears that even the 

 practice of regularly and systematically punching the tuyeres, which 

 is so essential a part of the work, as well as the philosophy of once for 

 all accepting it as inevitable in that light, instead of as an inconvenient 

 spasmodic drawback, were first introduced at the Parrott Works 



The Upright Vessel. — As intimated, the Parrott installation became 

 the mechanical prototype of the American converting plant, and has 

 laid the foundation for the wonderful perfection of apparatus which 

 has signalised the last 20 yea]"s in that country. \Mien a settled con- 

 structional basis for all parts had been arrived at, its vessels measured 

 externally 8|ft. hijih by 5ft. diameter. They took initial charges of 

 2,5001bs. of 45 per cent, matte, rising to 9,0001bs. with the corrosion 

 of the lining. The number of tuyeres, which consisted simply of 

 perforations of the lining, was 16. When lined, the vessels weighed 

 16.0001bs., and they withstood 16 blows. They were filled by means 

 of a swing spout from a remelting furnace standing on an elevated 

 platform behind the row of vessels. Originally tilted bv hand, subse- 

 quently by means of belting off a line shaft, they finally, in 1890, received 

 hydraulic apparatus for that pu pose. They were at first relined in 

 their trunnions, but were later on made removable and run in a half 

 turned-down, i.e., horizontal, position to the refining floor on a special 



(r) Prof. T. Egleston, School of Mines Quarterly, 1885, vol. VI., p. 320. 



