When he reversed the current, he found the needle deflected in the opposite direction. He experimented with various orientations of the needle and wire. Others began investigating the newly found connection between electricity and magnetism. Oersted continued working in physics. He started the Society for Dissemination of Natural Science, which was dedicated to making science accessible to the public, something he thought was very important.
In he established the Polytechnical Institute in Copenhagen. He was also a published writer and poet, and contributed to other fields of science, such as chemistry—for instance, in he produced aluminum for the first time. Oersted died in His discovery marked the beginning of a revolution in the understanding of electromagnetism, providing the first connection between what had been thought to be two very different physical phenomena.
APS News Archives. Librarians Authors Referees Media Students. Roughly 4, years ago, a Greek shepherd named Magnes is said to have been tending his sheep in a region of northern Greece called Magnesia. He took a step and suddenly found that the nails that held his shoe together and the metal tip of his staff were stuck fast to the rock he was standing on!
Intrigued, he began digging and discovered the first recorded lodestone. In the early A. Pliny attributed the powers of magnetite to magic, launching years of superstitious theories about the material, including the possibility that ships that had disappeared at sea had actually been attracted to magnetic islands.
On an unrelated but interesting note, Pliny died in the eruption of Pompeii. With a large lodestone deposit in Scandinavia and not enough light to navigate ships by in the winter, the Vikings had plenty of incentive to put the magnetic properties of lodestone to practical use.
As early as 1, B. The Chinese also invented the magnetic compass, probably earlier than the Vikings. After commercial trade with China was started by the Italians, especially after Marco Polo's trip, the magnetic compass was introduced to the rest of Europe. This made possible the exploration of the oceans by the Europeans, although the Norsemen had a monopoly for almost years and thus a big head start.
Today all ships large and small use magnetic compasses to navigate. The mineral magnetite is an iron oxide that is easily magnetized when it forms. The use of these needles gave the possibility to navigate in a complete darkness too. On the contrary, Pierre de Maricourt mentioned for the first time a dry compass in his " Epistola de Magnete " written in He had free-swinging, dry magnetic needles, which rotated on a pin.
They were the most important component of the dry compass. According to the legend the Italian Flavio Gioia from Amalfi was the first who invented this kind of compass. From the beginning of the 14 th century this compass appeared in the combination with the compass rose on Western ships.
Maricourt had systematically worked with magnets and their polarity and in his work dated he explained what he discovered: the same magnetic poles repel each other while different poles attract.
He wrote also that by breaking a magnet you get two small magnets. The explanation for this phenomenon was only found out pretty much later in the years. This is because of the natural rod shaped orientation of the elementary magnets in ferromagnetic materials.
This is why ferromagnetic materials can also be magnetized. This process was known early on. It happened by brushing some objects with a magnet. In this way, objects such as an iron nail or wire were lined in a parallel way to this magnet.
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