I suspended the small stone by a silk thread.
I heated it as it hung, in boiling water.
I heated the large one in boiling water.
Then I brought the large stone near to the suspended small one.
Which immediately turned its flat side to the side B of the large stone, and would cling to it.
I turned the ring, so as to present the side A of the large stone, to the flat side of the small one.
The flat side was repelled, and the small stone, turning quick, applied its high side to the side A of the large one.
This was precisely what ought to happen, on the supposition that the flat side of the small stone, when heated in water, is positive, and the high side negative; the side A of the large stone positive, and the side B negative.
The effect was apparently the same as would have been produced, if one magnet had been suspended by a thread, and the different poles of another brought alternately near it.
I find that the face A, of the large stone, being coated with leaf-gold (attached by the white of an egg, which will bear dipping in hot water) becomes quicker and stronger in its effect on the cork ball, repelling it the instant it comes in contact; which I suppose to be occasioned by the united force of different parts of the face, collected and acting together through the metal.