Abstract: A sheet stream sensing and control device for use in sheet feed systems having a motor driven conveyor transport means for advancing a reclining underlapped sheet stream toward a sheet removal means whereby the sheets are individualized and delivered to an operation such as a folding machine. The sensing and control device rests, vertically unconstrained, in a quiescent operating position upon the sheet stream and is responsive to the gradient of the surface discontinuity formed where the upper exposed surface of the foremost sheet joins the subsequent underlapped sheets. Conveyor control is effected when sheet stream advancement causes the surface gradient in the area of the discontinuity to exert pressure on the device electrical switch means to thereby deactivate the motor and interrupt sheet stream advancement. The sheet removal means continues to deplete the halted sheet stream thereby removing the switch pressure to energize the conveyor motor and advance the sheet stream.