[ 2I 5 ] 
dcred luminous, and, if brought nearer, there will 
iflue Sparks in the fame manner as when held to the 
End : And that this is owing to the Increafe of the 
attractive Force, feems plain ; for it was obferved in 
<■ the laft Experiment, the Attraction was capable of 
changing the Direction of the Rays at the Diftance 
of feveral Inches; whereas a Snap or Spark is fel- 
dom produced, when the Non-electric is held more 
than an Inch and half diftant. If therefore the 
Attraction decreafes, as the Squares of the Diftances 
increafes, as it probably does, the attractive Force 
will be many times greater in one Cafe than in 
the other, and if where the attractive Power was 
weaker, as in the former Experiment, there were fo 
many Rays of the electric Matter collected, as to be 
fufficient to produce a Light, it cannot be thought 
extraordinary, when the Attraction is fo greatly in- 
creafed on the nearer Approach of the Non-electric, 
that both the Denfity and Velocity of the Particles 
fhould be thereby increafed, fo as to produce Heat 
fufficient to fire the Vapour arifing from Spirit of 
Wine, or any other inflammable Vapour. 
And that the Quantity of the electric Particles is 
greatly increafed, as well as their Velocity, is evi- 
dent from that large Surface of the Rod, which, by 
the Approach of a Finger, is in one Spark divefted 
of them ; and which requiring fome time before it 
can be again fufficiently recruited, I apprehend is 
the Reafon of that Interval between the Sparks. 
And here it muft be obferved, that the Diftance 
the Point of the Non-electric is held at from the 
Rod, in order to produce the greateft Spark, muft 
be varied, in proportion as the Rod is electrified in 
a greater or lefs Degree ; the more ftrongly the Rod 
is 
