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7 Fill in the gaps.
a) reeling d) cable g) winch
b) cable-tool drillers e) cable-tool drilling's h) bit

c) bailing f) bullwheel i) a bailer

In spite of ________ (1) widespread use in the early days, the system had a couple of
drawbacks. One was that ________ (2) had to periodically stop drilling and pull the bit from the
hole. They then had to run a special basket, ________ (3), into the hole to retrieve and remove the
pieces of rock, or cuttings, the ________ (4) made. After ________ (5) the cuttings, they then ran
the bit back to bottom to resume drilling. If the crew failed to bail out the cuttings, the cuttings
obstructed the bit's progress. Bailing cuttings was not a big hindrance, however, because the cable-
tool system allowed the crew to do it quickly. Since the cable was wound onto a________ (6), or
windlass, called the "________ (7)" (see fig. 11), the crew simply reeled________ (8) on and off
the bullwheel to raise and lower the bit and bailer. ________ (9) cable was a fast operation.

8 Scan the text and correct spelling and grammar mistakes.
By itselves rotating a bit from pipe do not get the job done. The cuttings the bit makes must
be moved out of the way. Otherwise, they collect under the bit cutters and impede drilling. Recall
that the crew on a cabletool rig had to stop drilling and bail the cuttings. A rotary rig crew does not
have to bail cuttings because the rig circulates fluid while the bit drills and the fluid carries the
cuttings up to the surface As mentioned earlier crew members attach a rotary bit to hollow pipe
instead of to braided cable. The pipe is thus a conduit: a powerful pump on the surface moves fluid
down the pipe to the bit and back to the surface. This fluid pick up the cuttings as the bit make them
and carrie them to the surface where they are disposed of. The pump then move the clean mud back
down the hole

7