We were sorry that the poor experimenter wasted so much time and energy in trying to crowd us on to a piece of metal rod. He rubbed and he rubbed that metal, but it would attract nothing, and I shall tell you the reason. You know that we electrons hate overcrowding; indeed we always separate from one another as far as possible when there is no force pulling us together. We only crowded on to the amber because we could not help ourselves; we had no way of escape, for amber is a substance we cannot pass through. But we have no difficulty whatever in making our way along a piece of metal, and as soon as the rubbing began, some electrons moved off the metal by way of the man's arm and body to make room for those being crowded on to the metal from the rubber. And so there never was any overcrowding, and consequently no straining of the æther. But it was not long before we found that man had succeeded in cutting off our way of escape. He had attached a glass handle to the metal rod, and we were compelled to overcrowd upon the metal as we could not pass through the glass handle. Neighbouring light objects were attracted by the excited or "electrified" metal. Even this demonstration did not put man upon our track. Perhaps I should explain in passing, that when a glass rod is rubbed with a silk handkerchief we crowd on to the silk, and not on to the glass. This leaves the glass rod short of electrons, and the æther is strained so that light objects are attracted. Man did notice that there was some difference between a piece of amber and a piece of glass when these were excited. What the difference was he could not imagine, but to distinguish the two different conditions he said that the amber was charged with _negative_ electricity and the glass with _positive_ electricity. From that time forward man became of special interest to us. We felt sure that sooner or later he was bound to recognise that we were at work behind the scenes. It seemed to us, however, that man was desperately slow in turning his attention towards us, and we tried to waken him up in a rather alarming fashion, as I shall relate in the succeeding chapter. CHAPTER IV SOME GOOD SPORT _THE SCRIBE'S NOTE ON CHAPTER FOUR_ Men began to make glass plate machines for producing electrification on a larger scale. The electric spark is produced. The electron tells the story of the first attempt to store electricity in a glass jar. This is what we do now by means of a Leyden jar. A sudden expulsion of electrons from one object to another is called a discharge of electricity. Lightning is a discharge of electrons from a cloud to the earth or from cloud to cloud. In repeating Franklin's experiment of drawing electricity from thunder-clouds, a Russian professor received a fatal shock. CHAPTER IV SOME GOOD SPORT