In 1650 Otto von Guericke, the inventor of the air-pump, made a machine which looked like a little grindstone—a wheel of sulphur mounted on a turning axle, which being used with friction produced powerful electrical sparks and lights. He found by experiments with this machine that bodies thus exerted by friction may impart electricity to other bodies, and that bodies so electrified may repel as well as attract.
Sir Isaac Newton made an electrical machine of glass, and Stephen Gray, in 1720, said that if a large amount of electricity could be stored, great results might be expected from it.
Charles François Dufay detected that there were two kinds of electricity, which he called "vitreous" and "resinous."
A great discovery was coming. The first beams of a new planet were rising. How did there come into existence the "magical bottle" known as the Leyden jar?
At Leyden three philosophers were experimenting in electricity. "We can produce electrical effects," said one. "If we could accumulate and retain electricity we would have power."
They electrified a cannon suspended by silk cords. A few minutes after ceasing to turn the handle of the electrical machine which supplied the cannon with fluid, the charge was gone.
"If we could surround an electrified body with a nonconducting substance," said Professor Musschenbroek, "we could imprison it; we could accumulate and store it." He added: "Glass is a nonconductor of electricity, and water is a good conductor. If I could charge with electricity water in a bottle, I could possess it and control it like other natural powers."
He attempted to do this. He suspended a wire from a charged cannon to the water in a bottle, but for a time no result followed.
One day, however, Mr. Cuneus, one of the scientists, while engaged in this experiment, chanced to touch the conductor with one hand and the electrified bottle with the other. It was a mere accident. He leaped in terror. What had happened? He had received an electric shock. What did it mean? A revolution in the use of one of the greatest of the occult forces of Nature.
Terror was followed by amazement. Mr. Cuneus told Professor Musschenbroek what had happened.