Abstract: A hole boring apparatus includes an upright frame 20 along which can be moved a carriage 20 carrying a hydraulic motor 29 driving a square-section socket 29 in rotation. The top end of a train of square-section bars 40 is engaged in the socket, and an auger 40 surrounding the bars is axially slidable on the bars but is driven thereby in rotation. The auger is suspended from a carrier, relative to which the auger and bars can rotate. The auger is raised and lowered by means of a cable connected to one end of a lever mounted on the carrier. When the cable is untensioned the lever falls outwards into a position in which it engages either an axially-extending rib on the internal surface of a leading steel liner section for the hole or, if there is no liner, the side of the hole, so as to prevent the carrier from rotating with the auger and bars. When the cable is tensioned to lift the carrier, auger and spoil the lever is automatically freed from this engagement.