View related articles [~l ] XXXVI. ,tln .dttempt to analyse Sflle~. ] 3'# Professor B~zELzus*. THV. attempts hitherto made to decompose silica by means of the electric pile having left the problem undetermined, whether it can be reduced to a metalline body like other earths, I attempted to gain an analogous result by mixing it with powdered charcoal and filingq of iron~ and exposing the mixture, in a luted crucible, to a degree of beat sufli= cient for the fusion of the iron; hoping that the

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... n might An this case act somewhat similarly to quicksilver with the electric pile. a. Three grammes of iron filings mixed with 1~ gramme silica, and 0"66 of a gramme powdered chareoa], were put into a small crucible covered and luted in the ordinary way, and exposed to the heat of a blast furnaee for one hour. The mass when cold was taken out, the small reguli of iron were extracted by the magnet, and rubbed with the palm o[ the hand against paper, until, by continued rubbing on new and clean paper, they ceased to soil the paper. They l~ad a silver cotour; some of them admitted of being flattened ; others were brittl% according as they had taken up more ot less carbon. 1 "~ gr. of these polished metallic globules were then put into sulphuric acid diluted with six times as much water. They remained undissolved till heat was applied, when they dissolved slowly. When all action had ceased, the forms of the globules still remained~ but chaned in colour. Some were white as snow ; others black, an~lg:ueh like plumbago. When these were afterwards burned in an open fire, there remained siliceous earth of the form of the metallic globules. Those that had been white were still white, and those that had been black were now pale red. This earth amounled to S~z per cent. of the weight of the ferruginous globules. b. Having perceived the probability that these white skeleton globules of silica were derived from the soft re gull, and the black from those most charged with carbon ; I de. termined to try whether a silicated iron, tolerably free from carbon, might not be obtained by ~asingle~s charcoal. 1~ therefore mixed equal parts of fine powder of flint and iron-filings with ~,trth of their weight of pulverized charcoal, using a littlo mucilage of gum d-ragon to form a paste, of which tittle balls were made. These packed up in fine powder of flints were exposed to the lflast in the same man,. "Frora Afhandlingar i Fg~k, Keml och Mincralogi~ u~,ifn¢ afI¢]. Hfi~ F. Ber~eli~s. 8 H. ~tock.hotm, zSlO. Iler Downloaded by [University of California, San Diego] at 16:56 28 June 2016