[ *34 ] 
Here it {truck the upper edge of the flaple, which 
projected a little above the top of the bolt, melted it 
in a moft extraordinary manner ; the fpot, and in- 
deed feveral others, having run into a kind of fpiral 
form, which is raifed confiderably, as may be 
plainly diftinguifhed by a very {hallow magnifier, 
and often, as in this, by the naked eye. This effedt 
was fir ft obferved by Mr. Nairne. When it quitted 
this bolt, it ftruck upon a femicircular handle of iron, 
(firft 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 juft 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 w r ould 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 diredted by Dr. Franklin, 
I can have no doubt but the whole contents of the 
exploflon would have pafled this way, have been 
* Quere, is not this effe£t fomewhat analogous to Mr. 
bullin’s elc&iical experiment with a card P 
2 conducted 
