In a drilling method for creating a channel leading from surrounding soil
into a shaft which is separated from the soil by a wall, a channel is
drilled through the soil from a starting pit in the direction of the
shaft using a first drill head. The first drill head continues to drill
in this direction in order to create a breach in the wall, and a second
drill head is then used in the shaft to widen the breach in the wall by
drilling in the opposite direction with the second drill head.