Difficulties were encountered with reciprocating pumps for the continuous circulation of mercury. An all‐metal pump, without moving parts, operating on the principle of a polyphase induction motor was developed. The mercury flows in the annular region between two concentric tubes. Surrounding the tubes are coils connected to a polyphase supply. The result is a series of magnetic ripples traveling along the axis of the tubes which drag the mercury along by virtue of the currents induced in it. Lifts in excess of a meter and capacities in excess of 50 cc per second have been obtained.