| De magnete, magneticisque corporibus, et de magno magnete tellure, physiologia noua | |
| 1600 |  |
| William Gilbert(1544-1603) | |
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William Giilbert, a physician to Queen Elizabeth I, studied magnetism of the loadstone for almost 20 years. In this book, he compiled all known facts and popular sayings on magnets and on magnetism, and then confirmed each of those by experiment. Gilbert maintained that true scientific facts could only be acquired through experimentation and objective observation. He was the first to establish experimentation and as a scientific method. Therefore, this book was not only the first great scientific book in England, but also the first treatise of comprehensive experimental research to be written in Europe. Gilbert investigated the motion of the compass needle which was first reported and described by Peregrinus in 1269. In the course of this research he became particularly interested in the dip of the magnetic needle, discovered by Robert Norman C. 1576. Constructing a sphere of loadstone, on which an iron needle was set in various positions, Gilbert studied the behavior of the pivoting needle on the surface of the sphere. After careful and precise observations, he discovered that the behavior of the needle was exactly identical to the motion of the compass needle at various parts of the earth. Consequently, he concluded that the earth itself was giant magnet. Gilbert also made a study of the electrified body. Using an “electroscope”, the first electric measurement apparatus, which he invented himself, Gilbert ascertained that in addition to amber., many other materials such as glass, sulphur, or gems, could be electrified by rubbing them with fur, and thus had a capacity for attraction. Through these studies, Gilbert distinguished the difference experimentally between magnetic and electric attraction, a concept that only Cardano was aware of before Gilbert. Gilbert coined the word “electric” and thus established electricity as a science. Gilbert also presented the hypothesis in which the heavenly bodies have magnetic attraction and their motion conforms to these properties. Although the experimentation and results were not carried out mathematically, Gilbert’s work was nevertheless highly influential to men such as Bacon, Kepler, Galileo and Newton, both for its achievement and its methodology. |
