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32.0 Silieeous Genus. 14 argill, 0,11 of barytes, and 0,08 magnefia. Though this refult feems lefs improbable, ab- ftradtedly confidered, than any of the foregoing, yct Mr. Dolomieu thinks I muft have been'mif- taken, as (according to him) barytes eannot cxifl in the felfpar of granites, and no other ana- lyfis had difcovered it. Mr. Hoepfner, however, difcovered barytes in granite. 1 Chym. Ann. 1788, p. 134. And, fhortly after, Mr. Hafien- fraz, in the felfpar of St. Yrieux, found 0,70 filex, 0,12 argill, 0,09 magnefia, and 0,08 of barytes. 14 Ann. Chym. p. 14. Mr. Weftrumb alfo found barofelenite in the pureft felfpar. Magnefia was indicated in felfpar by Mr. Berg- man, Sciagr. §. 130. Though not found by many of the fubfequent analyfts; it did not, however, efcape Mr. Monnet, who found it jointly with filex, argill, and calx, in the felfpar he examined. 13 Roz. Suppl. p. 54. Nor Mr. Chaptal, who obferved it to exift in greater plenty in the red than in\vhite felfpar. Mr. Fabroni, who, happily for Italy, has lately diredted his attention to mineralogy, difcovered, in the felfpar of iEgyptian granite, 0,55 filex, 0,36 argill, 0,02 barytes, 0,04 magnefia, and 0,03 of iron. See Mr. De La Metherie’s late edi- tion of the Manual of Mr. Mongez. Mr. Scopoü, in felfpar of Baveno, found 0,63 filex, 0,17 argill, 0,06 magnefia, 0,02 calx, and 0,07 of iron , lofs 0,05. With refpedt to iron, it is highly improbable that this felfpar, which is of the pureft kind, fliould contain any. That which appeared may moft probably be afcribed to the Pruflian alkali he employed in the ana- lyfis. 6 From