2Q'2 PHILOSOPHICAL TRANSACTIONS. [anNO 1752. 



tlie stonn should come in the night, or if it happened by day, lie had it in his 

 power to observe all he proposed, without quitting his befl tir his business. 



The storm came at 5 in the oening ; and though he had not )"et time enough 

 to Ibnn a sufficient magazine of electricity, Ik? had nevertlieless v-er}' satisfectory 

 signs. TIte person who held the iron wire felt a conunotion ; and at the same 

 instant silken ribands were attracted by the electrical niagazinr. There came on 

 a great shower of rain and hail, which wetted tlic resin in the glass tube that 

 supported tl>e bar; ami after tliat tl>ete were no more signs of electricity. T^e 

 same thing happened in the garden ; where the silken cords, which in several 

 places interrupted the communication of tite electrized bodies with the non- 

 elcctrif^, having been wet, sensibly diminished the desirvd efFcct. The electri- 

 city howc\-er was very strong before the rain fell ; and the conunotions wx're felt 

 at about a foot distance : but the storm only passed by, and lasted no more i 

 the whole than 1 or 3 minutes. 



Letter 4. Dated St. C«rawra, Jul^ \1, I75'2.— M. le Monnier, who per- 

 formed the experimcmts, was oonvinocd that the higii situation, in which the bar 

 of iron was cuinmonly placed, b not abmlutdy necessary to produce the effects 

 of electricity : for a tin spedking trumpet suspeiKled on silken cords, about 5 or 

 6 feet from tite ground, Hm pcodooed very particular signs of electricity. 



A man placed on a cake of resin, and holding with his hand a wooden pole, of 

 about 18 fixi long, round which an in»n wire was twisted, was so well electrized 

 while it thuiMiercd, that very lively sparks were drawn from his 6oe and hands. 



Having taken away the oonxnunication of the electrical magazine with the 

 iron win*, which himg from the great wooden pole (this magazine consisting, as 

 mentioned in tlic last letter, of 6 great bars of iron, placxxl horizontally on glass 

 bottles, about 4 feet from the ground), this magazine was strongly electrized, 

 when the stormy cloud passed in the zenith. 



A man standing on the electrical cake in the middle of the garden, and simply 

 holding up one of his hands in the air, attracted with the other haiul wcxxi-shav- 

 ings, which were held to him on a piece of lead. Whence it evidently follows, 

 that the matter which is the cause of all the surprizing phenomena, which elec- 

 tricity affbnls us, fills the atmosphere in the time of a storm ; that it j)enetrates 

 us ; that we breathe it with the air ; and tliat the height usually given to the 

 iron bar, only serves to intercept the &r greater quantity of the electrical matter. 



At the time that M. le Monnier made his experiments, the Abbe, in his turn, 

 trieti to perfect the manner of bringing the electricity into his chamber. He 

 therefore increased tlie length of his wooden pole, which went out of his window, 

 and at the same time that of his iron rod, which was perpendicularly fastened 

 to its end. The greater the lengtli and height that tliese two were, the stronger 

 was tlie electricity in the chamber. 



