operator to change the setting of the element as the machine progresses through the field or is set up prior to its operation this element is connected to a counter unit 150 that counts the revolutions of the shaft 90 of the rotary flow divider as communicated by electrical lines 152 and 154 the counter unit incorporates a counter logic circuit for producing an electrical signal at a preset count as set in on the adjustable count selector 22 the counter is also connected to a normally open switch 156 interposed in electrical conduit 160 leading to the solenoid operated valve 110 electrical conduit 162 completes this circuit from the solenoid operated valve back to the counter 150 the normally open switch 156 is actuated through a hydraulic pressure responsive operator 164 that senses hydraulic pressure fluid levels in conduit 100 in its de energized position as shown the solenoid valve 110 positions the check valve 112 in conduit 106 72 which permits flow only toward conduit 72 the pilot operated check valves 132 and 142 permit flow only toward conduits 130 and 104 however the presence of pressure in conduits 100 or 96 is communicated through pilot lines 126 and 128 to open the check valves either 132.