Dayton has played an important role in the history of magnetic materials. A variety of magnet that you may be using every day was invented here: the modern rare earth permanent magnet. Dr. Sam Liu ...
The author starts from the dawn of authentic Chinese history (2637 B.C.) and ends with ... causing a wire carrying a current to rotate in a magnetic field.
As the time line at right shows, hundreds of times in our planet's history the polarity of the magnetic shield ensheathing the globe has gone from "normal," our current orientation to the north ...