[ 14° ] 



often be productive of the other, as is plain from Dr. 

 Franklin's experiments. 



If cold electrifies the air pcjitively in this climate 

 (which feems extremely probable), may it not elec- 

 trify it negatively at and about the place of our anti- 

 podes ? Does not a confideration of the effects dis- 

 covered in the Tourmalin favour this furmife ? 



The electricity of the air, in froity, foggy or 

 miSly weather, is not Strong enough to yield any 

 fpark, even by infulating a Sharp pointed wire in it, 

 which, however, attracts very light bodies at a fmall 

 distance; whilst, on the contrary, that of the clouds 

 generally affords considerably Strong fparks. 



When a fog becomes very thick, the cork-balls 

 approach i but when it returns to its former State, 

 they open again at their firit distance j and I have 

 obferved that, when it rained in foggy weather, the 

 balls clofed, and opened again on the fog's appear- 

 ance anew, after the rain had ceafed : there is, how- 

 ever, a certain degree of density neceffary in a fog, 

 in order that the balls might exert their greatest di- 

 vergency. 



Moit, if not all, fogs partake of a fmell much 

 like that of an excited glafs tube, and, indeed, fo 

 does the common air very frequently. 



As fogs fometimes appear in a very moift State of 

 the air, I was for fome time at a lofs to account on 

 what principle they could retain their electricity ; but 

 having at length remarked, that electrified bodies, 

 .infulated with fealing-wax, preferved their electricity 

 for a time in very damp air, I concluded that moif- 

 ture is but a very flow conductor. 



Having, 



