It may be observed in this experiment, that the _attractive_ power of bodies does not lie in _solids_, as has been falsly imagined, neither have such bodies any _centripetal_ or _centrifugal_ force; but that this _power_ and _force_ are given them from _without_. For, on placing the wire with the threads round the cylinder, they were all _forced_ (or as it is often called, _attracted_) towards the _earth_; but, on giving a _violent motion_ to the cylinder, they were drove from the cylinder, as if forced by a strong wind; but, by applying the hand to the glass cylinder, they were recalled, and all pointed to a center in the axis of the cylinder: and this _central_ direction might be altered at any time, by only moving the hand to different parts of the cylinder; the threads always pointing to the place where the _attrition_ was made: by which we find, that the _central_ force, both of the cylinder and the threads, are caused by the _attrition_ of the _air_ between your hand and the cylinder; whereas, at any other time, they are quite inactive: so we are assured that these _central_ forces which have been imagined to be _within_ the _solid_, are not there, but in the _air without it_. On putting something between any of the threads and the cylinder; then, those threads would return to their first and _natural position_, viz. point towards the center of the earth. So, as Mr. _Hauksbee_ observes, “in these small orbs of matter we have some little resemblances of the _grand phænomena_ of the _universe_.” Another thing observable was, “that by putting these threads within a glass, when they became extended, this position of the threads would be altered at any time on the approach of one’s hand, finger, or any other body, to the surface of the glass.” This is sufficient proof that the _light_, or as it is generally called, the _electrical effluvia pass_ through the _glass_, with as much ease as water does through a sieve. One thing which seemed a little surprising to Mr. _Hauksbee_ was, that upon exhausting the _gross air_ out of the tube or globe made use of in electricity, what he called the power of _attraction_, would cease; but upon suffering the air again to enter, it returned as vigorous as before. This must be the case; for (as was before observed) whenever the gross air is extracted by an air pump, the fluid remaining is nothing but _light_. So, whenever this attrition is performed on an exhausted globe (for want of the resistance of the gross air within, to force off the particles of air ground so small as _light_, and thereby to make an _expansion_ or _rarefaction_ round the glass globe, which has been shewn to be the cause of light bodies being _forced_ towards the globe) these particles of _light_ do immediately enter the globe on one side, and _force_ out the same quantity on the other; in the same manner as water through a sieve, without ever making any _expansion_ or _rarefaction_.