click image	1820 Hans Christian Ørsted was demonstrating the heating effects of the Voltaic Pile when he noticed that the needle of a compass sitting next to it spun off of north. This occurred every time the Voltaic Pile was in use. The phenomenon was hard to understand. However,  since an electric current could create a magnetic field, many scientists figured out that the opposite should be possible. They worked on it, but nothing until 12 years later Faraday figured out how to produce electricity by moving a magnet into a coil. Faraday also explained these phenomena by introducing the lines of force.   He found the geometry of these lines of force (magnetic field:)
Faraday also built the first motor that transforms electric energy into mechanical energy. See picture. A wire can move freely in a conductive fluid (mercury). In the center is placed a permanent magnet that create a stationary magnetic field. When the current flows into the wire, a magnetic force (a torque)  acts on the wire.  F =q VxB. A moving charge in magnetic field will " feel" a force perpendicular to the field and to the current.
Since a electric current can produce a magnetic field . Faraday asked: Can a magnet create a magnetic field ? Yes as long as the magnet moves inside a coil. This is the way we produce electricity. A changing  magnetic field will induce a changing electric current. This is called Faradays law of induction	click image
FAradya's life changed when he met Humphrey DAvy. He was supposed to be just an assistant for DAvy but he became more famous than his boss. He also became a famous and talented lecturer at the royal institution of London.	DAvy was a chemist. He discovered several chemical elements including Potassium, chlorine, iodine and Sodium using electrolysis :An electric current might decompose compounds into their constituent elements. In the first Bakerian lecture to the Royal Society in 1806 he described how electro analysis (electrolysis) decomposed pure water into the elemental gases Hydrogen and Oxygen. Davy embarked on a great series of experiments. He used the newly discovered battery (Volta) to create light arc and to vapoize elements in public. People were watching sparks for the first time. Davy's chemical lectures and demonstrations were brilliantly presented and became a fashionable social event. He was the first one to create an arc light. He used to inhale some laughing gaz before his lecture. He died from this habit to inhale nitrous oxide before his lectures.The gas became known as laughing gas. He "breathed 16 quarts of the gas in seven minutes" and became "completely intoxicated" with it. It would be forty-five years later before nitrous oxide would be used as a anesthetic by dentists.

Maxwell was home schooled. He was a genius. He wrote his first paper (Math) when he was 14 years old. Went to TRinity College, Cambridge. Found that the rings of Saturn was composed of small pieces. Created the first color photo using the 3 colors model. 

Maxwell made several contributions to the scientific community, but his most important achievement was his development of the equations of electromagnetic waves that were first envisioned by Michael Faraday. His theory was presented in 1873 and was entitled "Electricity and Magnetism." . His four equations unify electricity and magnetism.  This description of electromagnetism is at once simple and complex and is one of the greatest mathematical achievements of the 19th century. Even though these four equations were not directly intended for the theory of relativity, they have made a significant contribution in the development of the theories of relativity by later mathematicians and physicists. For example, Hendrik Lorentz used a slightly modified version of Maxwell's equations in order to develop the concept of length contraction when an object is traveling near the speed of light. Though Maxwell did not envision relativity at the time of the development of his equations describing electromagnetism, they definitely made a significant impact during the early formation of the concepts of relativity.

The 4 equations of Maxwell.  3. Gauss's law. describe the electric field created by a charge. This equation describes electrostatic phenomena. How an electric charge generates an electric field. The flux of the electric field through a close surface is proportional to the charge inside the surface. 4. describe the magnetic field produced by a magnet. A single pole can't be isolated. the magnetic filed comes out the North pole and enter the South pole. Or the magnetic flux going through a close surface is zero. 1. Faraday's law. A changing magnetic field (oscillating) produces a changing electric field. That is, you can produce electricity by moving a magnet in and out a close circuit (loop or coil) The flux of the magnetic field through the coil will change over time and produce a circulation of charges in the coil. 2. Ampere's law completed by Maxwell. A loop of direct current produces a constant magnetic field (Ampere's law) . But a changing current (oscillating electric field) will produce a oscillating magnetic field that will, in turn  produce an oscillating electric field... This equation predict the propagation of an EM wave (like visible light, radio wave, x-ray ..). A radio wave was then detected  by Henry Hertz and that proved the equations to be right.  Playing with the equations, Maxwell found the speed of light C. Amazing: The equation 4 explaining the magnetism uses the constant: Km = 10-7 The equation 3 explaining sstatic electricity uses the constant: Ke=9109 if you compute the ratio Ke/Km amazingly you get 9 1016 (m/s)2 which is the square of the speed of light.