. Journal. me time they were very useful as giving a footholdfor further research. The buttons of metal were found to be very different tothose obtained by the first process, being very soft, silveryand malleable, and entirely free from any impurity. It was further found that the cleaning of the oxide on the?-hovel as described did not involve the slightest loss oftin, as the washings on being collected were found to beentirely free from any trace of SnC)2. In the next method tried, the sample was prepared andcleaned as just described, and reduced in a similar mannerwith KCy, using at the same
. Journal. me time they were very useful as giving a footholdfor further research. The buttons of metal were found to be very different tothose obtained by the first process, being very soft, silveryand malleable, and entirely free from any impurity. It was further found that the cleaning of the oxide on the?-hovel as described did not involve the slightest loss oftin, as the washings on being collected were found to beentirely free from any trace of SnC)2. In the next method tried, the sample was prepared andcleaned as just described, and reduced in a similar mannerwith KCy, using at the same time an admixture of 5 grainspowdered charcoal, the idea being, if possible, to increasethe reducing power. It was noticed that during fusion of the charges, con-siderable effervescence took place, and the charges had atendency to boil over the sides of the pot, necessitating avery careful and somewhat slow fusion. Table No. 3 showssome results obtained in this manner. Percentage ofcleaned Percentage ofMetal found in cleaned Oxide. :i-l72-573-273-173-073574-073-57; :.72*072T,72-672-G72-«72-572-7;:;-u72-772-2 Actual Per-centage of Metal in the Ore. 66-4066-44 R*66-41 lit66-45 l;G0-3D D117-23 11(16-41 D117 -85 14I17-S4 1)68-83 I;68-58 D63-03 R07-99 R67-90 1)60-4GR63-07 R113-16 D62-73 R02-73 DG3-51 11 01-09 R63-03 D *RH. \V. Rennie. t D W. H. Derrick. In the above table Nos. 13 to 19 were samples of highclass black tin similar to those previously referred to, whileNos. 21 to 24 were of a similar character to the lowerquality oxide also previously mentioned. Each numberrepresents a separate individual sample of ore, and the chiefthing this table shows is the remarkable uniformity in thepercentage of metal found in the cleaned oxide, showingconclusively that the process we use for cleaning thesamples before reduction leaves in all cases a cleaned residueof uniform quality. It will be noticed here, as in Table No. 2,that the actual percentage o
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectchemist, bookyear1882
