Abstract: The invention relates to a drilling machine comprising a kelly (5) suspended from a boom (3) mounted for pivoting on a chassis (1), a rotary table (7) through which the kelly is movable axially, drive members provided in the rotary table for rotating the kelly and a rotary drilling tool (8), more particularly a ground auger fixed to the bottom end of the kelly.This machine is essentially characterized in that the rotary table (7) comprises at least two lateral protuberances (24) extending symmetrically with respect to the longitudinal axis of the kelly (5), in that the chassis (1) comprises two guide channels (26) disposed one opposite the other so as to receive the protuberances (24) and in that locking teeth (27) are provided for locking the protuberances (24) at any predetermined height in the guide channels (26).The machien of the invention further comprises members for boring by reciprocating for reaching depths of about 80 to 100 meters.