<div class="htmlview paragraph">Methods of freely, magnetically, suspending rotors in air, in various media, and in a vacuum are described. Rotors weighing from 10⁻⁶ lb to over 100 lb have been suspended and spun, but both larger and smaller rotors can be employed. Rotor speeds in excess of 10⁶ rps and centrifugal fields of over 10⁹ g have been obtained. When “coasting” freely in air at a pressure of 10⁻⁹ torr, ḟ/f ~ 10⁻⁹ sec⁻¹, were ḟ is the loss in rotor speed per second at a speed “f.” A double magnetic suspension also will be described.</div>