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and dropped on the bottom of the hole.
3. bit c any of a number of liquid and gaseous fluids
and mixtures of fluids and solids used in
operations to drill boreholes into the earth.
4. drilling d a metal pipe or tube used as a lining for a
fluid (mud) water, oil, or gas well.
5. e also known as stem, the weight bar used in
slickline operations to overcome the effects of
rig
wellhead pressure and friction at the surface
seal where the wire enters the wellbore.
6. f the revolving or spinning section of the
rotary
drillfloor that provides power to turn the
drilling
drillstring in a clockwise direction.
7. rotary table g a method of making hole that relies on
continuous circular motion of the bit to break
rock at the bottom of the hole.
8. winch h a machine for moving loads by means of a
flexible element
9. sinker bar i a lever that oscillates on a pivot and transmits
power in a manner producing a reciprocating
or reversible motion; used in rock drilling and
oil well pumping
10. walking j the machine used to drill a wellbore.
beam

Pre-reading and while-reading tasks
3 Scan the text and answer the following questions.

- What are the two drilling techniques?
- Why did the ancient Egyptians drill holes using hand-powered
rotating bits?

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