A Brief History

                The history of electromagnetism begins with the observations of lightning by our ancestors before modern historical records.  Observations of lightning were observations of electromagnetism.  These examinations lead to questions about how natural phenomenon worked.  Questioning what light was from the sun, or even a fire, would have been inquiries into electromagnetism.  Unfortunately, none of the comments on these observations were preserved for modern study.  Thus, we must move into recorded history to obtain a working knowledge of how electromagnetic theory came to be. 

            When considering a practical timeline leading to modern theory, the ancient Greeks will be first to be mentioned.  (Although it is highly unlikely they were the first to explore the electric and magnetic properties of materials).  The ancient Greeks knew amber could attract certain objects when rubbed with fur.  Also “there was a strange rock from the island of Magnesia which attracted iron.”¹  These were some of the most modern observations of electricity and magnetism.  

            Many scientists explored electricity.  One, famous in America, was Benjamin Franklin. However, Charles-Augustin de Coulomb discovered one of the most basic properties.  He found that electric forces obey an inverse-square law.  Michael Faraday set up the concept of the field.  The concept that an electric field is everywhere relative to a charge and dependent on the distance.²  Carl Gauss contributed greatly with the mathematics of electricity.  The most important aspect of the theory of electromagnetism was to establish a connection between electricity and magnetism.

            Hans Christian Oersted made an important observation, circumstantially, between electricity and magnetism during a classroom demonstration.  He noticed that a compass was affected by a battery creating a current in a nearby wire.  This led him to the discovery that magnetism can be made by an electric current.³  Faraday then ran with this, discovering connections between electrical currents and magnetic fields.  The close relationship between electricity and magnetism had been found.

            Today electromagnetism is used in many modern applications.  Cell phones and radios are a couple of the applications of electromagnetism.  Electromagnetism is critical in the operation of motors, the conversion of energy, and so on.  Before formally defining electromagnetism it’s best to look at electricity and magnetism separately.