[ 42 ] 
kc not electrified near them. I mud obferve, that 
Ice is not fo ready a Conductor of Electricity as 
Water ; fo that I very frequently have been difap- 
pointed in endeavouring with it to fire inflammable 
Subftances, when it has been readily done by a Sword* 
or the Finger of a Man. 
In the firft Paper * 1 had the Honour to lay before 
you upon this SubjeCt, I took notice of my having 
obferved two different Appearances of the Fire from 
electrified Subftances 5 viz- thofe large bright Flafhes, 
which may be procured from any Part of electrified 
Bodies, by bringing a Non-eleCtric unexcited near 
them, and with which we have fired all the inflam- 
mable Subftances mention'd in the Courfe of thefe 
Obfervations 5 and thofe, like the firing of wet Gun-* 
powder, which are only perceptible at the Points or 
Edges of excited Non -eleCtrics. Thefe laft alfo appear 
different in Colour and Form, according to the Sub- 
ftances from which they proceed : For, from polifh'd 
Bodies, as the Point of a Sword, a Silver Probe, the 
Points of Sciffors, and the Edges of the Steel Bar 
made magnetical by the ingenious Dr. Knight , the 
eleftrical Fire appears like a Pencil of Rays, agreeing 
in Colour with the Fire from Boyles Bhofphorus $ 
but from unpolifhed Bodies, as the End of a Poker, 
a rufty Nail, or fuch like, the Rays are much 
more red. The Difference of Colour here, I am 
of Opinion, is owing rather to the different Re- 
flexion of the electrical Fire from the Surface of 
the Body, from which it is emitted, than to any 
Difference in the Fire itfelf. Thefe Pencils of Rays 
- iflue 
* See thefe Tranfattions , N°. 477. 'p. 482, 483. 
