6. A VALVE FOR CONTROLLING THE RATE AND CHANGE OF RATE OF FLUID FLOW THROUGH A HYDRAULIC CIRCUIT COMPRISING A VALVE BODY, MEANS DEFINING A BORE IN SAID BODY, FIRST PORT MEANS IN SAID VALVE BODY FOR CONNECTING SAID BORE TO A SOURCE OF PRESSURIZED FLUID, SECOND PORT MEANS IN SAID VALVE BODY CONNECTING SAID BORE TO A HYDRAULICALLY CONTROLLED DEVICE IN SAID HYDRAULIC CIRCUIT TO MOVE SAID HYRAULICALLY CONTROLLED DEVICE IN A FIRST DIRECTION, THIRD PORT MEANS IN SAID VALVE BODY CONNECTING SAID BORE TO SAID HYDRAULICALLY CONTROLLED DEVICE TO MOVE SAID HYDRAULICALLY CONTROLLED DEVICE IN A SECOND DIRECTION, FOURTH PORTS MEANS IN SAID VALVE BODY CONNECTING SAID BORE TO A FLUID RESERVOIR, A VALVE SPOOL HAVING FIRST AND SECOND LOBES SLIDABLY MOUNTED IN SAID BORE, MEANS URGING SAID LOBES TO A FIRST POSITION WHEREIN SAID FIRST LOBE COMPLETELY BLOCKS SAID SECOND PORT MEANS AND WHEREIN SAID SECOND LOBE COMPLETELY BLOCKS SAID THIRD PORT MEANS, MEANS FOR URGING SAID LOBES IN A FIRST DIRECTION WHEREBY SAID SECOND PORT MEANS IS OPEN AND IN FLUID COMMUNICATION WITH SAID SOURCE OF PRESSURIZED FLUID AND SAID THIRD PORT MEANS IS OPEN AND IN FLUID COMMUNIATION WITH SAID RESERVOIR, FIRST STOP MEANS LIMITING THE MOVEMENT OF SAID LOBES IN THEIR FIRST DIRECTION AT A SECOND PREDETERMINED POSITION PARTIALLY OPENING SAID SECOND AND THIRD PORT MEANS, WHEREBY SAID HYDRAULICALLY CONTROLLED DEVICE IS MOVED IN ITS FIRST DIRECTION AT A RELATIVELY LOW AND CONSTANT VELOCITY WHEN SAID LOBES ARE AT SAID SECOND PREDETERMINED POSITION, MEANS RESPONSIVE TO THE MOVEMENT OF SAID LOBES IN THEIR FIRST DIRECTION FOR MOVING SAID FIRST STOP MEANS AT A CONSTANT AND PREDETERMINED VELOCITY WITHIN A RANGE OF VELOCITIES TO A THIRD POSITION WHEREIN SAID SECOND AND THIRD PORT MEANS ARE OPENED A GREATER AMOUNT, WHEREBY SAID HYDRAULICALLY CONTROLLED DEVICE IS ACCELERATED DURING THE MOVEMENT OF SAID LOBES FROM SAID SECOND PREDETERMINED POSITION TO SAID THIRD PREDETERMINED POSITION AND WHEREBY SAID HYDRAULICALLY CONTROLLED DEVICE IS MOVED AT A RELATIVELY HIGH AND CONSTANT VELOCITY WHEN SAID LOBES ARE AT SAID THIRD PREDETERMINED POSITION, SAID MEANS FOR MOVING SAID FIRST STOP MEANS TO SAID THIRD POSITION INCLUDING MEANS TO ESTABLISH AND MAINTAIN ANY DESIRED VELOCITY WITHIN SAID RANGE, MEANS FOR MOVING SAID FIRST STOP MEANS AT A CONSTANT AND PREDETERMINED VELOCITY WITHIN A RANGE OF VELOCITIES FROM SAID THIRD POSITION TO SAID SECOND POSITION TO THEREBY MOVE SAID LOBES IN THEIR SECOND DIRECTION, WHEREBY SAID HYDRAULICALLY CONTROLLED DEVICE IS DECELERATED DURING THE MOVEMENT OF SAID LOBES FROM SAID THIRD PREDETERMINED POSITION TO SAID SECOND PREDETERMINED POSITION, SAID MEANS FOR MOVING SAID FIRST STOP MEANS TO SAID SECOND POSITION INCLUDING MEANS TO ESTABLISH AND MAINTAIN ANY DESIRED VELOCITY WITHIN SAID RANGE, MEANS FOR URGING SAID LOBES IN THEIR SECOND DIRECTIUON WHEREBY SAID THIRD PORT MEANS IS OPEN AND IN FLUID COMMUNICATION WITH SAID SOURCE OF PRESSURIZED FLUID AND SAID SECOND PORT MEANS IS OPEN AND IN FLUID COMMUNICATION WITH SAID RESERVOIR, SECOND STOP MEANS LIMITING THE MOVEMENT OF SAID LOBES IN THEIR SECOND DIRECTION TO A FOURTH PREDETERMINED POSITION PARTIALLY OPENING SAID SECOND AND THIRD PORT MEANS, WHEREBY SAID HYDRAULICALLY CONTROLLED DEVICE IS MOVED IN ITS SECOND DIRECTION AT A RELATIVELY LOW AND CONSTANT VELOCITY WHEN SAID LOBES ARE AT SAID FOURTH PREDETERMINED POSITION, MEANS RESPONSIVE TO THE MOVEMENT OF SAID LOBES IN THEIR SECOND DIRECTION FOR MOVING SAID SECOND STOP MEANS AT A CONSTANT AND PREDETERMINED VELOCITY WITHIN A RANGE OF VELOCITIES TO A FIFTH POSITION WHEREIN SAID SECOND AND THIRD PORT MEANS ARE OPENED A GREATER AMOUNT, WHEREBY SAID HYDRAULICALLY CONTROLLED DEVICE IS ACCELERATED DURING THE MOVEMENT OF SAID LOBES FROM SAID FOURTH PREDETERMINED POSITION TO SAID FIFTH PREDETERMINED POSITION AND WHEREBY SAID HYDRAULICALLY CONTROLLED DEVICE IS MOVED AT A RELATIVELY HIGH AND CONSTANT VELOCITY WHEN SAID LOBES ARE AT SAID FIFTH PREDETERMINED POSITION, SAID MEANS FOR MOVING SAID SECOND STOP MEANS TO SAID FIFTH POSITION INCLUDING MEANS TO ESTABLISH AND MAINTAIN ANY DESIRED VELOCITY WITHIN SAID RANGE, MEANS FOR MOVING SAID SECOND STOP MEANS AT A CONSTANT AND PREDETERMINED VELOCITY WITHIN A RANGE OF VELOCITIES FROM SAID FIFTH POSITION TO SAID FOURTH POSITION TO THEREBY MOVE SAID LOBES IN THEIR FIRST DIRECTION, WHEREBY SAID HYDRAULICALLY CONTROLLED DEVICE IS DECELERATED DURING THE MOVEMENT OF SAID LOBES FROM SAID FIFTH PREDETERMINED POSITION TO SAID FOURTH PREDETERMINED POSITION, SAID MEANS FOR MOVING SAID SECOND STOP MEANS TO SAID FOURTH POSITION INCLUDING MEANS TO ESTABLISH AND MAINTAIN ANY DESIRED VELOCITY WITHIN SAID RANGE.

7. IN A VALVE, A BODY DEFINING A FLUID PASSAGE AND CONTAINING FLOW CONTROL MEANS RECIPROCABLE IN THE BODY ALONG A PREDETERMINED PATH OF TRAVEL BETWEEN A FIRST POSITION FULLY OPENING SAID PASASGE AND A SECOND POSITION FULLY CLOSING SAID PASSAGE, THE IMPROVEMENT COMPRISING MOVABLE STOP MEANS CONTROLLING MOVEMENT OF SAID FLOW CONTROL MEANS BETWEEN SPACED POSITIONS ON SAID PATH, AT LEAST ONE OF SAID SPACED POSITIONS LYING BETWEEN SAID FIRST AND SECOND POSITINS SO THAT THE MOVABLE STOP MEANS CONTROLS THE MOVEMENT OF SAID FLOW CONTROL MEANS ONLY DURING A PORTION OF THE TRAVEL OF SAID FLOW CONTROL MEANS, MEANS FOR EFFECTING CONTROLLED MOVEMENT OF SAID STOP MEANS AT A CONSTANT AND PREDETERMINED VELOCITY WITHIN A RANGE OF VELOCITIES IN AT LEAST ONE DIRECTION BETWEEN SAID SPACED POSITIONS, SAID MEANS FOR EFFECTING MOVEMENT OF SAID STOP MEANS INCLUDING MEANS TO ESTABLISH AND MAINTAIN ANY DESIRED VELOCITY WITHIN SAID RANGE AND FURTHER INCLUDING MEANS TO VARY THE DURATION OF SAID CONTROLLED MOVEMENT.