"The repellency between the cork ball and the shot is likewise destroyed, 1st, by sifting fine sand on it--this does it gradually; 2dly, by breathing on it; 3dly, by making a smoke about it from burning wood; 4thly, by candle-light, even though the candle is at a foot distance--these do it suddenly. The light of a bright coal from a wood fire, and the light of a red-hot iron, do it likewise, but not at so great a distance. Smoke from dry rosin dropped on hot iron does not destroy the repellency, but is attracted by both shot and cork ball, forming proportionable atmospheres round them, making them look beautifully, somewhat like some of the figures in Burnet's or Whiston's _Theory of the Earth_. "N.B.--This experiment should be made in a closet where the air is very still, or it will be apt to fail. "The light of the sun thrown strongly upon both cork and shot by a looking-glass, for a long time together, does not impair the repellency in the least. This difference between firelight and sunlight is another thing that seems new and extraordinary to us. "We had for some time been of opinion that the electrical fire was not created by friction, but collected, being really an element diffused among and attracted by other matter, particularly by water and metals. We had even discovered and demonstrated its afflux to the electrical sphere, as well as its efflux, by means of little, light windmill wheels made of stiff paper vanes fixed obliquely, and turning freely on fine wire axes; also by little wheels of the same matter, but formed like water-wheels. Of the disposition and application of which wheels, and the various phenomena resulting, I could, if I had time, fill you a sheet. The impossibility of electrizing one's self, though standing on wax, by rubbing the tube, and drawing the fire from it; and the manner of doing it by passing it near a person or thing standing on the floor, etc., had also occurred to us some months before. Mr. Watson's ingenious _Sequel_ came to hand; and these were some of the new things I intended to have communicated to you. But now I need only mention some particulars not hinted in that piece, with our reasonings thereupon; though perhaps the latter might well enough be spared. "1. A person standing on wax and rubbing the tube, and another person on wax drawing the fire, they will both of them (provided they do not stand so as to touch one another) appear to be electrized to a person standing on the floor; that is, he will perceive a spark on approaching each of them with his knuckle. "2. But if the persons on wax touch one another during the exciting of the tube, neither of them will appear to be electrized.