lister’s TRAVELS IN FRANCE.

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A fquare loadftone made into a terrella, will near take up as much weight as it didbefore, though a great deal of the ftone is loll in the rounding, by virtue of the dif-ferent (hoeing.

He entertained us full two hours with experiments neatly contrived about the effeftsof the loadftone.

The experiment of approaching a loadflone to the fpring of a watch is very fine; itcaufes the balance to move very fwift, and brought yet nearer, to (top quite and ceafemoving.

Another experiment was an inch broad plate of iron, turned into a ring of about fourinches diameter, which had evidently two north and two fouth poles, which he faid hehad feen in a loadftone, and had contrived this in imitation of nature. The workingof them with filings of fteel, drigged upon a plate, fet upon the ring, did clearly ma-nifeft the double polarity.

> Alfo the fufpending of a needle in the air, and a ball of fteel upon the point of it,by a thread, which a weight kept down, that it could not afcend higher than fuch adiftance within the fphere of the a&ivity of the loadftone.

Again, the free working of the needle in water, through brafs, gold, ftone, wood,or any thing but iron. He told us, he had a ftone, which would work through aftone wall of eighteen inches.

Laflly, he demonftrated by many experiments, how the effluvia of the loadftonework in a circle, that is, what flows from the north pole comes round, and enters thefouth pole ; on the contrary, what flows from the fouth pole, enters the north, and inits way puts in order all fuch filings of fteel it meets with; that is, according to thedifpofition of its own whirling, and the circular lines it keeps in its flying about theloadftone. Indeed, it is pleafant to fee, how the fteel filings are difpofed; and in theirarrangement, one clearly fees a perfect image of the road, which the whirling invifiblematter takes in coming forth, and re-entering the poles of the loadftone.

He fhewed us a loadftone (awed off that piece of the iron bar, which held the ftonestogether at the very top of the fteeple of Chartres . This was a thick cruft of ruft,part of which was turned into a ftrong loadftone, and had all the properties of a ftonedug out of the mine. Monfieur de la Hire has printed a memoir of it; alfo Monfieurde Vallemont a treatife. The very outward ruft had no magnetic virtue, but the inwardhad a ftrong one, as to take up a third part more than its weight unfhod. This ironhad the very grain of a folid magnet, and the brittlenefs of a ftone.

Thefe gentlemen, w ho have writ of this, have in my opinion milled their purpofe,when they enquire, how it comes to pafs to be thus turned ; for it is certain, all ironwill in time go back into its mineral nature again, notwithftanding the artifice of melt-ing and hammering. I have feen of thofe hammered Spanilh cannon, which had lainmany years.buried in the ground, under the old fort at Hull in Yorkshire , which werethoroughly turned into brittle iron ftone, or mine again j and w'ould not own the load-ftone, no more than the reft of our Englifh iron mine, till it was-calcined, and then(hewed itfelf to be good iron again. Alfo I have feen and had by me, a piece of woodtaken out of Lough-Neah in Ireland , which was not only good iron mine, but a load-ftone too; fo that it is evident nature, in this fort of mine, goes backwards and for-wards, is ge nerated and regenerated ; and therefore Monfieur de la Hire has w'ell ufedthe term of vegetation in this affair, which I had done many years before him, in mybook “ De Fontibus Medicis Angliae,” that is, out of iron mine will growj and out ofmine, a loadftone j as in the petrified wood.

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