486 



METALS. 



copper, together with wood-charcoal, all finely 

 ground and intimately mixed, the charge was put in- 

 to a plumbago crucible, then heated in an air-furnace 

 at an intense heat for from three to four hours. It was 

 found when the pot was taken out. that, still sus- 

 pended in the charcoal, and not run down to the bot- 

 tom, were innumerable fine shots of a bright white 

 metal ; these being separated by washing and placed 

 again in the crucible and heated, fused, I may say 

 easily, into a prill or button covered with a green 

 layer of vitreous slag. 



'The alloy was found to be very hard and very 

 brittle when hot, but when cold, although still hard, 

 it rolled with ease and was highly elastic. The pro- 

 portions of alloy were about copper 75 per cent., 

 manganese 25 per cent. When the simple alloy had 

 been produced in sufficient quantities, compound 

 alloys with zinc were tried in various proportions, 

 and these again rolled with complete success. Cer- 

 tain mixtures of copper, zinc, and manganese, pos- 

 sess the advantage, Doth over German silver and 

 yellow metal, that, whereas the one will only roll 

 cold, and the other hot, the manganese alloy rolls 

 from hot to cold. 



The laboratory experiments havingbeen completed, 

 an air-furnace was built in which a 100-lb. plumbago 

 crucible was used. The results were precisely the 

 same as those obtained in the laboratory, only it 

 was found that, by stirring the charge a few min- 

 utes before the crucible was taken out of the fire, 

 by far the greater portion of the metal that before 

 was in small fine shot, needing very careful wash- 

 ing, now settled to the bottom of the pot, and could 

 be poured out as a bar or ingot, the slag also melt- 

 ing, and the unconsumed charcoal floating on the 

 top. This experiment was continued until several 

 hundred- weights of the alloy were produced, so that 

 it may be subjected to various tests, and also that 

 some approximate estimate of its cost and value 

 might bo formed. 



As a simple alloy in which the proportions of man- 

 ganese ranged from five per cent, to thirty per cent., 

 it is both malleable and ductile, with a tenacity con- 

 siderably greater than that of copper. 



"With zmc, a compound alloy, very closely re- 

 sembling some of the qualities, not the best, of 

 German silver, is obtained. The alloy of cop- 

 per and manganese would also combine with tin, 

 lead, and other metals, and from these castings 

 were made which were applied as bearings for ma- 

 chinery. 



Alloy of Lead with Platinum. M. A. Bauer, 

 having observed the experiments made by M. 

 Deville, in which it was found that alloys of 

 lead and platinum readily decomposed in con- 

 sequence of the conversion of the lead into 

 white-lead, tried the proportions of three parts 

 of pure lead to one part of platinum. The re- 

 sulting alloy was so brittle that it could be 

 readily pulverized, and the powder then ob- 

 tained was moistened with water and placed 

 under a bell-jar, exposed to the action of car- 

 bonic acid, oxygen, and acetic acid. The con- 

 version of the lead into white-lead took place 

 rapidly ; and, after it appeared that all the lead 

 was converted into white-lead, the powder 

 was treafed with acetic acid, and the residue 

 again exposed under the bell-jar to the action 

 of the same substances. This process having 

 been repeated several times, there remained at 

 last a steel-grayish colored crystalline powder, 

 which only appeared to be finely-divided plat- 

 inum. On being treated, however, with di- 

 lute nitric acid, the author found that the 

 powder consisted of an alloy of lead and plati- 



num, which contained in 100 parts platinum, 

 48.82 ; lead, 51.18 ; corresponding to the for- 

 mula Pt + Pb. This alloy has a specific gravity 

 of 15.77, is readily decomposed by mineral 

 acids, but withstands boiling with acetic acid ; 

 and, when rapidly fused, it is, after cooling, a 

 bismuth-like, crystalline, very brittle metallic 

 mass. The alloy, submitted in a muffle to 

 the process of oxidizing ignition, fuses, the 

 lead is driven off, and platinum left. 



Aluminium Weights. Dr. T. L. Shipman 

 writes as follows to the Chemical News, in 

 praise of the value of aluminium for accuracy 

 and unchangeableness in weights: 



For the last ten years that is, since May, 1860 

 I have made use of a set of aluminium (division of 

 the gramme) weights. On the average these weights 

 have been used at least twice or three times a day 

 for a period of somewhat more than ten years. They 

 were supplied by MM. Collot, Freres, of Paris. Lat- 

 terly, I have tested them and found them as accurate 

 as the day on which they were first used. They are 

 almost as brilliant as when new. The larger weights, 

 0.5, 0.2, and 0.1 gramme, show slight traces of tar- 

 nish, but their weights are still quite accurate. Dur- 

 ing this period of ten years these weights have never 

 been touched except by a pair of soft brass nippers, 

 and they have never been left exposed to the air for 

 more than a few minutes at a time. However, they 

 have, of course, been exposed for a minute or two at 

 intervals to an atmosphere more or less impregnated 

 with acid or alkaline vapors, and if we add these odd 

 minutes together, it will be found that these gramme 

 divisions in aluminium have had to undergo a con- 

 siderable amount of " atmospheric influence " during 

 the period of which I speak. The set contains four- 

 teen weights, from i a gramme to i a rniligramme. 

 As to brass or copper divisions, I have always con- 

 sidered them inaccurate, for they tarnish very rapidly 

 in an atmosphere which, for that of a laboratory, 

 might be considered tolerably pure. 



Metallic Zirconium. A German chemist, 

 Franz, has obtained the metallic base of zir- 

 conia, in a nearly pure state. He first prepares 

 the oxide of zirconia by treating the native 

 mineral with bisulphate of potash, and the 

 decomposition of the sulphate of zirconia, first 

 by fusion with caustic soda, and next by treat- 

 ing the fused mass so obtained with sulphuric 

 acid, and precipitating the zirconia from the 

 aqueous solution of the sulphate by means of 

 ammonia. Metallic zirconium was prepared 

 by the decomposition of the fluoride of potas- 

 sium and zirconium, SKFl-fZrFh, by means 

 of aluminium and a high temperature. The 

 metallic zirconium so obtained is not quite 

 pure, and was found to consist, in 100 parts, of: 

 zirconium, 98.34; aluminium, 1.03; and sili- 

 con, 0.17. The temperature required for this 

 reduction so as to obtain crystalline zirconium 

 is at least as high as that of the melting-point 

 of copper. 



Silver and the Chlorin'e Treatment. In a 

 book lately published on the success of the 

 chlorine process for the extraction of silver 

 from refractory ores, the author, Mr. G. Kus- 

 tel, says that in Nevada and Idaho the ore 

 contains only from 6 to 10 per cent, of sul- 

 phurets, yet gives a good result. As no pyrites 



