Let’s forget politics for a moment and think about physics. William Gilbert and Galileo Galilei are regarded as the two founders of experimental physical science. The common scholarship of their time was largely non-experimental. Scholars read Greek and Latin texts (including the Bible) to discover the ancient “truth” by logic and inference. “Truth” was considered virtually immutable, and experimentation was considered almost sacrilegious and an insult to God. Gilbert and Galileo believed that theories and “truth” should be tested using rigorous experiments. In his book, De Magnete (1600), Gilbert stated: “Men of acute intelligence, without actual knowledge of facts, and in the absence of experiment, easily slip and err.”
One of William Gilbert’s experiments led to his discovery that our planet has two magnetic poles and that the Earth acts like a giant magnet. He also built the first apparatus to detect an electric charge and coined the Latin word electricitas, which was shortly translated into English as electricity.
William Gilbert’s primary profession was as a medical doctor, and he was the personal physician of Queen Elizabeth and King James. His medical practice was so successful that he had the time and money to conduct groundbreaking scientific experiments.
While Gilbert used science to correctly describe many fundamental natural phenomena, he was also a product of his age. For example, he believed that planets have souls and that each planet’s soul was magnetic. As Gilbert thought planets have souls, Newton was also an alchemist who wanted to turn ordinary metals into gold. Like Sir Isaac Newton, as long as Gilbert “stayed in his lane” and conducted valid experiments, his conclusions were generally accurate. However, when either Newton or Gilbert speculated beyond their evolving scientific method, they quickly slipped and erred. No one is perfect, especially when hubris takes control. We must continually remind ourselves that science is the search for truth, not a factory of certainty or fantasy worlds.
A Short Summary of Magnets
Based on the experimental research of Gilbert and others, we now know that the uniform directional motion of electrical charges creates magnetism. The electrons in objects, such as wood or plastic, have roughly the same number of electrons that spin in one direction as the other, so they cannot be magnetized. However, the electrons in many metals spin primarily in the same direction and can be turned into “full” magnets after being more strongly “aligned” by a more strongly magnetized object.
There are several types of magnets, including the earth itself. However, I will discuss only two types of magnets. One is a simple bar magnet, and the other is a horseshoe magnet. The main difference between the two is the distance between the magnetic poles. The poles of a bar magnet are at opposite ends and, therefore, as far apart as possible. The distance between the poles of a horseshoe magnet is relatively close together. Additionally, the relative magnetic pull of the respective magnetic fields is stronger for the horseshoe magnet because the poles are closer together and in the same plane, as indicated in the following diagrams.
The horseshoe magnet was the first magnet that could lift more weight than it weighed itself. The shape of a horseshoe magnet also allowed it to stay magnetized longer than a bar-shaped magnet, particularly if it had an iron bar “keeper” between its two poles. Historically, other magnet shapes destroyed themselves in their own demagnetizing field.
Inventor William Sturgeon used the horseshoe magnet that later laid the foundation for the electrical telegraph. Magnetism has been used to convert mechanical energy to electrical energy over the last two centuries. Much of modern society is based on our understanding of magnetism. Experimenters in the 1830s discovered that rotating a magnet created an electrical current. Without magnetism, we would not have our electric grid.
Interestingly, the latest experiments with nuclear fusion show that a new, limitless (I know we have heard this before) energy source could be possible within a few decades. This new energy source will not require hydraulic power or fossil fuels. Furthermore, it will not have the deleterious byproducts of nuclear fission. This controlled nuclear fusion is made possible by using super-powerful magnets to channel and control the super-heated plasma created by the immense heat generated by hundreds of powerful laser beams.
Magnetism is not only integral to most modern technological products, but the earth’s magnetic shield protects us from harmful cosmic rays and allows life to exist on Earth.
Despite its many advantages, magnetism can be dangerous. If people come armed to an MRI exam, they will pay the price. Magnetism does not care about the Second Amendment or gun laws in other countries.
For more information about magnets, if you are curious:
https://byjus.com/question-answer/which-is-more-powerful-between-a-bar-magnet-and-a-horseshoe-magnet