Page:Philosophical Transactions - Volume 002.djvu/125

 places deeper, in some shallower; in some places narrower, in some broader; but lies altogether, and is perfect Lead, only in the outside, covered with reddish Earth.

To the Queres in the sixth Title, I cannot say much; it must be resolved by them, that melt the Lead-Ore, with which I have not been much acquainted, save only, that they beat the Ore small; then wash it clean in a running stream; then lift it in Iron-Rudders; then they make of Clay or Fire-stone a Hearth or Furnace, which they set in the ground, and upon it build there Fire, which is lighted with Char-coal, and continued with young Oaken-gadds, blown with Bellows by mens treading on them: And after the Fire is lighted, and the fire place hot they throw their Lead-Ore upon the Wood, which melts down into the Furnace; and then with an Iron-Ladle they take it out, and upon sand cast it into what form they please.

So far this account, which is hoped will be made in time more compleat, and succeed with the like Answers from other places.

This Letter was written by the Intelligent and Experienced Monsieur Petit, Intendant of the Fortifications of his Most Christian Majesty, to the Publisher, as followes;

Have received yours, wherein you desire to know my sentiment about the present Variation of the Needle; intimating withal, that an Artist in London affirms, that whereas heretofore the Declination was East-ward, 'tis now about one degree and a half to the West.

Nothing can be more welcome to me, than to have occasion given me to discourse of this Subject, especially to the Philosophers of England, whence the Philosophy of the Magnet Rh