C *4° 3 
X. Some Conjectures concerning Eledricity, and 
the Rife of Vapours, by J. T. Defaguliers, 
LL. 2). F. R. S. 
Read [une 24. T is proper firft to mention by way of 
,/42 ‘ Preliminary, That Monf. ‘Du Fayes 
Aflfertion of Two Sorts of Electricity is found to be 
true by Obfervations and Experiments, viz. That 
Bodies endowed with the Vitreous Eledricity repel 
one another, and attrad thofc that have the Refinous 
Electricity ; on the contrary, thofe that are endowed 
with the Refinous Eledricity repel one another, but 
attrad thofe that have the Vitreous Eledricity. 
I luppofe Particles of pure Air to be Eledric Bodies 
always in a State of Electricity, and that Vitreous 
Electricity. 
ift , Becaufe Particles of Air repel one another 
without touching, as has been deduced from Experi- 
ments and Obfervations. 
2 dly, Becaufe, when the Air is dry, the GlafsTube 
rubbed (or only warmed) throws out its Effluvia> 
which the Air drives back to the Tube, from whence 
they dart out anew, and fo move backwards and 
forwards with a vibratory Motion, which continues 
their EleCtricity. 
3 dly, Becaufe the Feather made eledric by the 
Tube, and darted from it, keeps its EleCtricity a long 
time in dry Air ; whereas, when the Air is moift, the 
moift Particles, which are non-eledric, being attraded 
by the Feather, foon make it lofe this Eledricity, 
which alfo happens even to the Tube in a little time. 
From 
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