Abstract: A method and a magnetic separator are disclosed particularly for the removal of particles of low magnetic susceptibility, present usually as impurities and often largely of submicron sizes, from aqueous slurries of clay or other minute mineral particles. A high intensity magnetic field is established between vertically spaced pole members in the general direction of flow of the slurry through a canister disposed between confronting surfaces of the pole members, the canister being packed with multitudinous elongate ferromagnetic elements which present surface irregularities with each contacting, yet also spaced from others, so as to constitute a flux conductive matrix that diverts the slurry flow into diverse courses and concentrates the flux at myriad points therein.

Abstract: A chart recording instrument having electromechanical servos which move a pen or stylus in the X-direction along a paper chart, and move the chart with respect to the pen in the Y-direction. A novel mechanism provides for ease in loading and unloading charts, and for accurate relocation of the chart, whereby a chart can be removed from the machine and then replaced accurately without disturbing any of the gain or zero control settings. Thus a curve can be recorded, the chart removed, and then put back to record another curve in the same family. These functions are controlled by a three-position lever which lifts and lowers the pen, raises and lowers pinch rollers in the Y-axis chart drive system, controls a pair of chart positioning stops, and switches appropriate positioning voltages to the servos.