Earth working apparatus

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The present invention relates to a device for levelling a land surface, comprising a (scraping or grading) blade (2) suspended from a first suspension point (3a) and a second suspension point (3b), a hydraulic circuit with a coupling for feed and discharge of hydraulic liquid under pressure, a first hydraulic cylinder (5a) connected to the hydraulic circuit for defining the height (4a) of the first suspension point (3a) relative to the land surface (7), a second hydraulic cylinder (5b) connected to the hydraulic circuit for defining the height (4b) of the second suspension point (3b) relative to the land surface (7), wherein the first and second hydraulic cylinders (5a, 5b) are placed in a master-slave arrangement and wherein the hydraulic circuit is provided with a controllable bypass (18) around the second hydraulic cylinder (5b) in order to enable individual control of the first hydraulic cylinder (5a), and thereby of the relative height of the first and second suspension points (3a, 3b).