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Here it ftruck the upper edge of the flaple, which 

 projected a little above the top of the bolt, melted it 

 in a mofr. extraordinary manner ; the fpot, and in- 

 deed feveral others, having run into a kind of fpiral 

 form, which is raifed considerably, as may be 

 plainly diftinguifhed by a very fhallow magnifier, 

 and often, as jn this, by the naked eye. This effect 

 was nrft obferved by Mr. Nairne. When it quitted 

 this bolt, it ftruck upon a femicircular handle of iron 

 (nrfl tearing out a large piece from the door), the 

 upper part of which hath three melted fpots, be- 

 fides a fingle one at the upper edge of it. But, 

 in quitting it, the electricity melted only one fpot 

 at the lower edge *, which I think, as Mr. Bell (a 

 gentleman who was with us) obferved, was a cri- 

 terion whereby to judge of the direction of the fluid. 

 To the left of this door, at the diftance of eleven feet 

 four inches, came down a leaden pipe, which ter- 

 minated at the ceiling, and there juffc entered a pitched 

 trunk of fir (which indeed was the cafe with every 

 leaden pipe about the building). Here the lightning 

 exploded, rending the trunk, and doing other flight 

 damage in and about a window, to which it was 

 attracted by an interrupted and irregular communi- 

 cation of metal. I would beg leave to remark, 

 that, had this pipe of lead been continued to the 

 bottom of the building, and thence conveyed into 

 the earth, in the manner directed by Dr. Franklin, 

 I can have no doubt but the whole contents of the 

 explofion would have pafTed this way, have been 



* Quere, is not this effect fomewhat analogous to Mr. 

 Lullin's ekctiical experiment with a card ! 



2 conducted 



