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making my experiments on that fide of the houfe 

 where the wind had leaf! power. 



I have found the air, in winter, at a proper diftance 

 from buildings, trees, mails of mips, &c. very fen- 

 fibly electrified, during a frofty or foggy ftate of the 

 weather ; and in mifts too, but in a lefs degree : I 

 have alfo difcovered fmall figns of it in calm and 

 cloudy weather. 



The air, in fummer, never mewed any fign of 

 electricity, except when a fog happened in the cool 

 of the evening, or at night 5 in which cafe, I always 

 difcovered manifeft marks of electricity, fenfibLy, 

 weaker than thofe obferved in winter fogs, but pre- 

 cifely of the fame kind, that is, pojitive. 



I have often examined the ftate of the air, at the 

 time of an. Aurora borealis, and could not difcover 

 any indication of electricity, except when a fog had 

 appeared at the fame time; in which cafe, the elec- 

 tricity has been, in every- refpect, the fame as that of 

 a fog at any other time. Once, indeed, during an 

 Aurora borealis on a remarkable fere ne night, 1 dif- 

 covered fome figns of a. very; weak pcfji*ve electric- 

 city. 



As the- electricity of the air is- .generally pofiiroe (I 

 never knew an exception but one, which preiented 

 itfelf during- a fog on a winter day,., that proved un- 

 commonly warm), is it not reafonable to believe, that 

 cold electrifies the atm.ofp.here pofitivelyS and, if fo, 

 may not one be led- to imagine, that heat electrifies 

 it negatively?. But this I. only offer as a conjecture, 

 not being able to advance any thing deeiiive on the 

 lubject., and knowing that one fort of electricity may 



% 2. often- 



