A study was made of the magneto-hydrodynamic centrifuge, a direct-current motor with a mercury armature. Centrifuging action is derived from the rotating mercury which, at sufficient speeds, assumes the shape of a hollow ring. A development prototype is designed and tested to determine the feasibility of such a centrifuge. Results were promising and indicated that the basic operational principle is sound and feasible. A paddle wheel was rotated at 2000 rpm by a rotating ring of mercury at an estimated mercury input power of 5 watts.