Abstract: There is disclosed a method of controlling the level of a self-levelling device comprising a table to be controlled in level, an air spring supporting the table, a sensor for contactless detection of an amount of displacement of the table from a reference position, an inlet valve for supplying air under pressure to the air spring through an inlet port therein, and an outlet valve for discharging air from the air spring through an outlet port therein. An interval of time for actuating the inlet valve and/or the outlet valve to return the table to the reference position is computed from the amount by which the table is displaced. The inlet and/or outlet valve is then actuated for the calculated interval of time to adjust the table level through the air spring.