j$6 Appendix.

When the Apparatus has lost Part ofits natural Share of this Fluid, by the Ap-proach of excited Wax to one End of it,or is electrified negatively; the electricalFire is attracted and imbibed by the Ballsto supply the Deficiency; and that moreplentifully at the Approach of excitedGlass, or a Body positively electrified, thanbefore; whence the Distance between theBalls will be increased, as the Fluid sur-rounding them is augmented. And in ge-neral, whether by the Approach or Recess*of any Body ; if the Difference between theDensity of the internal and external Fluidbe increased or diminished ; the Repulsionof the Balls will be increased, or diminishedaccordingly.

Experiment 5 .

When the insulated Tin Tube is notelectrified, bring the excited Glass Tubetowards the Middle of it, so as to be nearlyat Right Angles with it, and the Balls atthe End will repel each other; and themore so, as the excited Tube is broughtnearer. When it has been held a few Se-conds, at the Distance of about six Inches,withdraw it, and the Balls will approach

each