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7 Fill in the gaps.

a) reeling d) cable g) winch
b) cable-tool drillers e) cable-tool h) bit
drilling's
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

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