Row markers

Claim 1

A MARKER TO BE ATTACHED TO A HORIZONTAL TOOL BAR OF A TRACTOR, SAID TOOL BAR HAVING PLOWS ATTACHED THERETO, AND SAID TRACTOR HAVING A SUPPLY OF HYDRULIC FLUID UNDER CONTROLLED PRESSURE; COMPRISING THE COMBINATION: A FRAME, SAID FRAME HAVING AT LEAST TWO CLAMPS THEREON, EACH OF SAID CLAMPS ENCIRCLING SAID TOOL BAR THUS CLAMPING THE FRAME THERETO, SAID FRAME HAVING A HYDRAULIC CYLINDER PIVOTED TO IT, SAID HYDRAULIC CYLINDER BEING CONNECTED TO SAID SUPPLY OF HYDRAULIC FLUID, A PISTON ROD WITHIN THE CYLINDER WHICH MOVES AXIALLY WITHIN THE CYLINDER RESPONSIVE TO THE PRESSURE OF THE HYDRAULIC FLUID, A LEVER PIVOTED TO SAID FRAME, SAID PISTON ROD PIVOTED TO SAID LEVER SO THAT MOVEMENT OF THE ROD RELATIVE TO THE CYLINDER WILL IMPART ROTATIONAL MOTION TO THE LEVER; A LINE EXTENDING THE LENGTH OF THE TOOL BAR, SAID LINE BEING CONNECTED TO SAID LEVER SO THAT MOVEMENT OF THE PISTON ROD CAUSES RECIPROCAL MOVEMENT OF THE LINE THROUGH THE LEVER; TWO MARKER BEAMS, ONE OF SAID MARKER BEAMS ON EACH END OF THE TOOL BAR, EACH MARKER BEAM PIVOTED TO A MARKER CLAMP, EACH MARKER CLAMP CLAMPED TO THE TOOL BAR, SAID PIVOT BETWEEN EACH MARKER BEAM AND MARKER CLAMP HAVING A HORIZONTAL AXIS NORMAL TO THE TOOL BAR SO THAT EACH MARKER BEAM MAY BE ROTATED FROM LONGITUDINALLY OF THE TOOL BAR TO ANGLE UPWARD FROM THE TOOL BAR, A COLUMN RIGIDLY ATTACHED TO EACH MARKER CLAMP AND EXTENDING ABOVE SAID MARKER CLAMP, A PULLEY AT THE TOP OF EACH COLUMN, A POST RIGIDLY ATTACHED TO EACH MARKER BEAM, AND EXTENDING ABOVE SAID MARKER BEAM WHEN IT IS IN THE HORIZONTAL POSITION, AND A PLOW ATTACHED TO EACH MARKER BEAM IN EARTH WORKING ENGAGEMENT WHEN THAT MARKER IS APPROXIMATELY HORIZONTAL, THUS MAKING A MARK WHICH THE OPERATOR OF THE TRACTOR MAY FOLLOW LATER; SAID LINE EXTENDING THROUGH BOTH PULLEYS AND ATTACHED TO BOTH POSTS SO THAT RECIPROCATION OF THE LINE CAUSES ROTATIONAL MOVEMENT OF ONE MARKER BEAM UPWARD AND ALLOWS ROTATIONAL MOVEMENT OF THE OTHER MARKER BEAM DOWNWARD BY GRAVITY.