A magnetic analyzer capable of bending the four million electron volt bean of the Virginia Polytechnic Institute electrostatic accelerator has been constructed. The magnet is the circumferential yoke, double-focusing type. Tests show its field to be uniform within one percent along its 16-inch radius, its magnetization curve to agree with the design requirements, and its cooling system to be more than adequate. A motor-generator set and a motor amplydine have been obtained for the magnet power supply, delivery now awaited. A voltage feedback system has been designed for field stabilization, and the considerations in supplying nuclear magnetic resonance equipment to field stabilization have been examined. / Master of Science