Page:Philosophical Transactions - Volume 001.djvu/356

 82. Whether or no, having once brought the Ore to fusion, they melt all the Metal it self, to have it the more pure? And, if they do, with what circumstances they make the fusion?

83. Whether they have any Signs, whereby to know whether the Fusion have been well or ill perform'd; and the Metal have obtain'd the perfection, to be expected from such Ore, melted in such a Furnace?

84. Whether they observe any great difference in the goodness of the Metal, that first melts, from that of the rest of the Metal which comes afterwards in the same or another operation? And whether the Rule holds constantly? (For, though they observe in Tin-Mines, the best Metal comes first, yet in the works of an Industrious friend of mine, he informs me, that the best Metal comes last.)

85.Whether the produced Metal be all of the same goodness? And if it be, how good it is in reference to the Metal of other Mines, or other parts of the same Mine or Vein? And if it be not, what differences are observ'd between the produced portions of Metal; and what disparity that amounts to in the price?

86. What are the Wayes of distinguishing them, and estimating their goodness?

87. Whether they do any thing to the Metal, after it is once brought to Fusion, and, if need be, melt it over again, to give it a melioration? (As when Iron is refined, and turn'd into Steel;) And what distinct Furnaces, and peculiar Ways of ordering the Metals are employ'd to effect this improvement? With a full description of them and the Tools in all Circumstances, observ'd in the refining of Metals.

88. Whether in those places, where the Metal is melted, there be not elevated some Corpuscles, that stick to the upper parts of the Furnance, or Building? And, if there be, whether they be barely fuliginous and recrementitious exhalations, or, at least in part, Metallin Flowers? (As in the Cornish Tin-mines, after some years they usually destroy the thatch'd Houses, where the Ore hath been melted, to get the stuff, that adhears to the insides of the Roofs, out of which they melt store of excellent Tin.)

89. Whether the Metal, being brought to fusion, affords Rh