An agricultural machine comprises a chassis (1) and a device for displacing a working organ (9) along the surface of the field, which contains a hermetic chamber (3) with a window (4), a source of a fluid agent pumped into the chamber (3) under pressure and a flexible sleeve (7) which is wound on a drum (5) and which contains a traction element (8) inside it. A device which carries the working organ (9) is mounted on a section of the traction element (8) coming out at the loose end of the sleeve (7) and is movably connected to the flexible sleeve (7). The loose end of the sleeve (7) passes through the chamber (3), is turned inside out and hermetically fixed in the window (4) of the chamber (3). The annular cavity thus created (A) is connected to the chamber (3) and under the influence of the fluid agent changes its volume and displaces along the field the sleeve (7) which pushes in front of it the device carrying the working organ (9).