This book deals with the two fundamental subjects of electromagnetism. It is a useful text for courses in electromagnetism, electrical circuits, mathematical methods of physics, and the history and philosophy of science. It covers how to calculate force between two current carrying circuits, and net force on a part of a closed circuit. The calculation of the mutual inductance between two circuits and self-inductance of a single closed circuit is also described. Experiments explain the main expressions of Ampere and Grassmann. A must to help deepen the knowledge of the mind of any student of science.