The mysterious Unipolar Dynamo, so simple that even the earth's core has one, so powerful that it forges metal alloy billets and launches a rail gun! This handbook has all the history, operating principles, practical construction details, and pictures of Faraday disk/unipolar/homopolar generators. Investigating the Paulsen UFO story and the DePalma claims of overunity, the author began an earnest scientific endeavour in 1980 to build and test a homopolar generators (HPG) for the elusive 'back torque' which had never been measured before in a one-piece HPG. This project helped to complete his Master's Degree in Physics at SUNY Buffalo. What does the torque push against when the magnet spins with the disk? How can the back torque or armature reaction be diminished or counteracted? These and other burning questions are answered in the only book of its kind on the subject of homopolar generators.