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* SOME years ago I difcovered, by Mr. Canton's 

 electrometer, defcribed in the Philof. Tran factions, 

 Vol. XLVI1T. p. 783. that the air of Ireland is, 

 during the winter feafon, \n almofl a conftant flate 

 ■of pofitive electricity j which, however, is fo weak, 

 that, in order to obferve it fatisfactorily, I have al- 

 ways found it neceflary to have the cork-balls fuf- 

 pended from threads of a middling finenefs, fix or 

 feven inches in length, quite {freight, and to avoid, as 

 much as poffible, any interruption from the wind. 



I have likewife had frequent recourfe to the fol- 

 lowing contrivance, by which I was enabled, within 

 doors, to purfue my inquiries with greater accuracy 

 and advantage : having procured a (lender tapering 

 piece of wood, about five feet long, to the fmaller 

 end of which an electrometer was affixed, by means 

 of a fmali hook; I placed it out from an open garret 

 •window, and faflened the other end with a fmall 

 hafp to one of the jambs : I had alfo at hand another 

 piece of wood, in the ends of which, a fmall glafs 

 tube and a flick of fealing-wax had been inferted. 

 Either of thefe was occafionally excited, and applied 

 near the cork-balls, in order to determine more pre- 

 •cifely the kind of electricity with which they might 

 happen to be affected ; and I was always careful in 



* I commenced my experiments on the air in the year 1761, 

 and thofe on the clouds in the year 1762. I continued them un- 

 remittingly, as opportunity offered, till the year 1770, when 

 my occafions brought me to England. I have repeated my ex- 

 periments, with regard to the common air, in different places 

 here, and find it the fame as that in Ireland, 



making 



