Abstract: The present invention relates to an apparatus for drilling holes in the ground. The apparatus comprises a cylindrical drilling tool having one end coupled to a motor assembly for rotating the tool by way of an elongate rotatable sleeve. A hydraulic jack is disposed in the sleeve for rotation therewith. The piston rod of the jack extends longitudinally of the drilling tool and carries a valve-action member arranged to allow drilled material to enter the drilling tool and to retain the material therein. The piston rod is movable longitudinally relative to said tool for the discharge of said material.The apparatus of the invention is able to drill holes rapidly in a large variety of soils.