578 



METALLURGY. 



ladle-like vessel, suspended on trunnions in 

 front of a cupola- furnace. Cast-iron is then at 

 once tapped out from the cupola, as hot as 

 possible, and run on to the converter, in the 

 proportion of from 50 to 80 per cent, of the 

 weight of the ore charged. It is said that 

 the melting and complete reduction of the ore 

 take place instantaneously, the metallic lead 

 sinks to tJie bottom, where it is covered by the 

 liquid iron, and the slag, in a pa?ty condition, 

 floats on the surface. The lead and iron are 

 tapped off at the bottom, after which the slag 

 is thrown out, and all is ready for a new 

 charge. A portion of the iron used is con- 

 verted into sulphide of iron by taking up the 

 sulphur remaining in the ore, and this sulphide 

 of iron is entangled in the slag. The iron not 

 so consumed is cast into pigs, and is put 

 through the cupola again to serve for working 

 another charge. 



Zine. A new method has been introduced 

 by M. Piallat for dealing with the various forms 

 of waste zinc resulting from the different 

 manufactures in which the metal is used. The 

 point aimed at is to get rid of the solder 

 which is usually mingled with the clippings, 

 and which spoils the zinc for direct uses. M. 

 Piallat places his cuttings, etc., in a sort of bas- 

 ket, in which they can be subjected to heat 

 and to centrifugal force at the same time. The 

 actual basket-like container is surrounded by 

 an outer envelope. Under the influence of the 

 heat, which may be applied in the form of su- 

 perheated steam or heated air, and the cen- 

 trifugal action, the solder is melted, detached 

 from the zinc, and driven to the exterior of 

 the container, where it collects and is drawn 

 off. The value of the solder alone, which is 

 remelted and cast into bars, is sufficient, it is 

 said, to pay all the costs of the operation. The 

 zinc saved by this process, after being further 

 purified by fusion, is very suitable for use in 

 making small castings, and is sold at a relatively 

 low price. 



Alloys. Mr. Richard Pearce, of Denver, Col., 

 has described some new crystalline alloys of 

 bismuth, gold, silver, and other metals. In 

 the treatment of auriferous copper containing 

 bismuth, globules were obtained of a grayish- 

 white substance which proved to be bismuth 

 containing in solution, as it were, a crystalline 

 alloy of bismuth and gold, the crystals of which 

 were separated by the action of nitric acid. 

 Their composition is, gold, 69 '94 per cent. ; sil- 

 ver, 0-63 per cent. ; and bismuth, 29'43 per cent. 

 The melting of the residue with a flux gave a 

 bronze-colored alloy having a specific gravity 

 of ^15-47, from which were separated by nitric 

 acid gold-yellow crystals, having the composi- 

 tion^ Au, 21 Ag. By remelting some of the 

 original bismuth compound with a quantity of 

 silver atomically corresponding with the quan- 

 tity of gold in it, crystals were obtained of an- 

 other alloy of gold and silver with a little bis- 

 muth and copper; and other alloys, but in 

 smaller and less perfect crystals, of gold and sil- 



ver were obtained, in all proportions 

 on the amount of silver used and the stren^ 

 of the acid. Crystals of an alloy of gold and 

 copper were obtained precisely in the same 

 way by substituting copper for silver. Crys- 

 tals were also obtained containing three metals, 

 in the proportion gold, 60'16; silver, 21-2; 

 copper, 18-63. The experiments indicate that 

 gold will not combine with bismuth if silver 

 or copper is present in sufficient quantity. Ex- 

 periments were also made in melting platinum 

 and bismuth, the result of which was the pro- 

 duction of a black crystalline powder. On the 

 addition of copper, a jet-black residue of bin- 

 oxide of platinum was obtained. 



A new alloy, called " glass composition," 

 introduced by Mr. Louis Dill, of Frankfort-on- 

 the-Main, is said to possess the qualities of 

 the best composition used for bearing surfaces. 

 It contains a certain percentage of a vitreous 

 substance which, expressed hi figures, is very 

 trifling, but is said to be sufficient to impart to 

 the alloy a durability and uniformity not be 

 fore reached. Even at a high rate of speed 

 the heating of journals is avoided and thei 

 unequal wear prevented. Its cost is less than 

 that of other alloys of equal efficiency, and 

 is said to stand wear and tear remarkably well 

 even with a small amount of lubrication, anc 

 to be proof against atmospheric influence an( 

 the action of diluted acids. 



M. Henri Vivarez finds in silicious bronze 

 a conductibility comparable to that of cop 

 per, and a mechanical resistance greater than 

 that of iron. The silicon may be introduce( 

 in various proportions, the mechanical resist 

 ance varying inversely as the conductibility 

 In telegraphy, galvanized iron wire, which 

 weighs 155 kilogrammes per kilometre, can 

 be replaced by wires of silicious bronze, weigh 

 ing only 28 kilogrammes; and in telephony 

 iron wires of 25 kilogrammes can be replace( 

 by wires of silicious bronze weighing only 8'45 

 kilogrammes. 



M. Lecoq de Boisbaudran reports of his ex- 

 aminations of the alloys of indium and gallium 

 that the points of complete fusion are difficuli 

 to determine, because, from the beginning ol 

 the process, the fluidity increases gradually, 

 while the metal remains more or less pasty. 

 The first alloy, 2 In + Ga, is white, granulated, 

 and easily sliced with a knife. In + Ga is alsc 

 white and nearly solid, but much less hard 

 than the preceding alloy. In + 2 Ga is soft, 

 pasty, and white. In -f 4 Ga is white, and 

 begins to melt at 16-5 C., at which tempera- 

 ture the other alloys are hard. It is liquid at 

 50 C., while the first alloy, the hardest of the 

 series, is viscid at 75 C. 



Processes. Messrs. E. H. and A. H. Cowles, 

 with Prof. 0. F. Mabery, of Cleveland, 

 have successfully employed a method for^thi 

 reduction, on a commercial scale, of varipi 

 metals by the direct application of electricity. 

 The principle on which their process depen< 

 is that of producing an extremely high tern- 



