A jacquard pattern control mechanism for a circular knitting machine (20) comprising a plurality of rocker bar supporting members (40) slidable in grooves (26) along which move knitting elements (27), a plurality of elongate rocker bars (44) pivotally mounted on the rocker bar supporting members (40) for movement about medial pivots, the opposite end portions of the rocker bars (44b,44c) being selectively movable between operative and inoperative positions and having magnetically attractable sections (44f,44g) thereon, and magnet attracting devices (50) operatively associated with the opposite end portions of the elongate rocker bars for selectively attracting one of the magnetically attractable sections at opposite ends of the rocker bars to pivot the rocker bars and selectively move the opposite end portions thereof to the other operative and inoperative positions. The magnetic attracting devices (50) comprise a permanent magnet and a pair of electromagnets (51,52) disposed on opposite sides of the permanent magnet and connected in series, the permanent magnet having an extension extending outwardly towards the rocker bars and having a pair of wing portions extending outwardly from the center portion of the extension, generally parallel to the rocker bar supporting members (40). The wing portions of the permanent magnet cooperate with the core parts of the electromagnets (51,52) in providing stronger magnetic fields for attraction of the magnetically attractable sections (44f,44g) of the rocker bars (44).