In De Magnete Gilbert carefully classified all the materials that were the subjects of his experiments. He listed the things he tried and pointed out the ones that showed attraction and the ones that did not. He also pointed out the subjects that exerted a greater degree of attraction than others. To classify things more accurately, he invented a machine that he called an electroscope. It was a simple device, consisting of little more than a straw that was balanced so that it could swing freely. Gilbert rubbed an object and placed it in machine. Then he watched the straw to see if it would be attracted or not to the objects. Gilbert kept careful notes, and accounts of all these experiments were contained in his book.
Gilbert never learned what caused the strange attraction. But his careful observations and the records of his experiments served as a basis for some of the great discoveries in electricity that was to follow. Little he did know as he turned the pages of the volume that his work would create great controversy. He was later called the “Father of Electricity”. That mysterious force now had a name. Many scientists were not eager to accept new ideas. They were satisfied with the explanations of the wonders of nature that had been handed down from ancient Greece. However, some scientists believed and were impressed with Gilbert’s scientific approach. They were interested in his findings and were eager to learn more about the new force called Electricity.