Abstract: A drill in which a drilling apparatus is releasably mounted on the bottom of a drill string and on release can be withdrawn upwardly through the drill string by wire-line. The main cutting bit is disposed on the bottom end of the removable apparatus and the apparatus includes expandable cutters disposed above the main cutting bit to ream the hole cut by the main bit to permit the drill string to follow down the hole. The cutters are retracted for withdrawal of the apparatus.