Magnets and magnetism have fascinated people for centuries. But the real story of magnetic fields begins in 1269, when a French scholar named Petrus Peregrinus de Maricourt used iron needles to map the magnetic field on a spherical magnet. He noticed that the field lines crossed at two points—he named them “poles,” like the North and South Poles of Earth. He also made an important observation: no matter how small a magnet is cut, it always has both a north and south pole.

Almost 300 years later, an English scientist named William Gilbert confirmed Peregrinus’ work. In 1600, Gilbert published De Magnete, a groundbreaking book where he stated that Earth itself is a giant magnet. This marked the beginning of magnetism as a true science.

In 1750, John Michell proposed that magnetic forces follow an inverse square law, meaning the force becomes weaker as distance increases. Charles-Augustin de Coulomb later proved this with experiments in 1785. He also confirmed that north and south poles always come in pairs. Building on this, Siméon Denis Poisson created a mathematical model in 1824 to explain how magnetic fields behave.

Iron filings—tiny bits of iron—play an important role in showing magnetic fields. Although originally just a byproduct of metalwork, they became useful tools in science. When sprinkled over a card on top of a magnet, the filings align to show the invisible magnetic field. They’re used in classrooms, toys, and even for analyzing magnetic patterns on credit cards and hard drives.

The connection between electricity and magnetism was discovered by Hans Christian Ørsted in 1820. During a lecture, he noticed a compass needle moved when an electric current was turned on. This showed that electricity can create a magnetic field. Ørsted’s discovery opened the door to the field of electromagnetism.

All these fascinating discoveries and more are beautifully explored in Foundations of Physics by Lawrence Brown. Brown, an accomplished inventor and retired engineer, brings over 30 years of experience to this compelling book. He also served as a high school teacher, making his writing both educational and easy to understand.

Foundations of Physics takes readers on a journey from ancient discoveries to the roots of modern technology. If you’re curious about how humans uncovered the forces that shape our world, this book is for you.

Pre-order your copy on Amazon today and dive into the world of human ingenuity!