4l6 PHILOSOPHICAL TRANSACTIONS. [aNNO l/SQ. 



(for the gilt paper happened to lie with its gilded side uppermost,) it was found 

 to terminate on the point in the gilt paper where the impression appeared, and 

 there the impression pointed downwards. Again, when. the hole in the lower 

 part of the quire was traced from below upwards, it was found to terminate on 

 the point in the leaf fronting the gilding, where the impression was, and there 

 the impression pointed upwards. The facts above-mentioned seem to leave it 

 without doubt, that the stroke had been given at the same instant, upwards and 

 downwards ; but that the electrical power from above, and from below, had 

 seized on the gilding, dissipated part of it in vapour, and by that means become 

 so weak, that each of them could afterwards only make an impression on the 

 paper, marking the respective directions of their course. 



Mr. S. communicated these observations to Dr. Franklin ; but as no conclu- 

 sion can, with certainty, be drawn but from facts, confirmed by repeated trials, 

 he desired to have the satisfaction of making a few experiments with the Dr. in 

 regard to this matter ; to which he readily consented. For that purpose Mr. 

 S. waited on him one morning about the middle of June ; and the better to 

 ascertain what was essential in the facts, he varied the circumstances a little 

 fi-om those above. 



In the middle of a paper book of the thickness of a quire, he put a slip of 

 tin foil ; and in another of the same thickness he put 1 slips of the same sort of 

 foil, including the 1 middle leaves of the book between them. On striking the 

 two different books, the effects were answerable to what he expected. In the 

 first, the leaves on each side of the foil were pierced, while the foil itself re- 

 mained unpierced ; but, at the same time, he could perceive an impression had 

 been made on each of its surfaces, at a little distance one from another ; and 

 such impressions were still more visible on the paper, and might be traced as 

 pointing different ways. In the 2d, all the leaves of the book were pierced, 

 excepting the 2 that were between the slips of foil ; and in these 2, instead of 

 holes, the two impressions, in contrary directions, were very visible. 



Mr. S. afterwards repeated these experiments with another similar instrument, 

 and he met with nothing but what confirmed him in the opinion of 2 distinct 

 counteracting powers. All the remarks he had been able to make in the repeti- 

 tion of experiments, that need to be added to what he had before observed, may 

 be reduced to the 3 following. 



1°. When a quire of paper, without any thing between the leaves, is pierced 

 with a stroke of electricity, the 2 different powers keep in the same track, and 

 make but one hole in their passage through the paper : not but that the power 

 from above, or that from below, sometimes darts into the paper at two or more 

 sundry points, making so many holes, which, however, generally unite before 

 they go through the paper. What he means is, that he never yet could observe 



