CHAPTER XXXVII
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MISCELLANEOUS MINERAL SUBSTANCES USED IN THE INDUSTRIAL ARTS.
Alum—Alum Mines of Tolfa—Borax—The Suffioni in the Florentine Lagoons—China-clay—How formed?—Its Manufacture in Cornwall—Plumbago—Emery—Tripolite 458
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.
MISCELLANEOUS MINERAL SUBSTANCES USED IN THE INDUSTRIAL ARTS.
Alum—Alum Mines of Tolfa—Borax—The Suffioni in the Florentine Lagoons—China-clay—How formed?—Its Manufacture in Cornwall—Plumbago—Emery—Tripolite 458
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