F
. Boats needing to be lifted up enter the canal basin at the level of the Forth & Clyde
Canal and then enter the lower gondola of the Wheel. Two hydraulic steel gates are
raised, so as to seal the gondola off from the water in the canal basin. The water
between the gates is then pumped out. A hydraulic clamp, which prevents the arms of
the Wheel moving while the gondola is docked, is removed, allowing the Wheel to
turn. In the central machine room an array often hydraulic motors then begins to rotate
the central axle. The axle connects to the outer arms of the
G
. Wheel, which begins to rotate at a speed of 1/8 of a revolution per minute. As the
wheel rotates, the gondolas are kept in the upright position by a simple gearing
system. Two eight-metre-wide cogs orbit a fixed inner cog of the same width,
connected by two smaller cogs travelling in the opposite direction to the outer cogs
–
so ensuring that the gondolas always remain level. When the gondola reaches the top,
the boat passes straight onto the aqueduct situated 24 metres above the canal basin.
H
. The remaining 11 metres of lift needed to reach the Union Canal is achieved by
means of a pair of locks. The Wheel could not be constructed to elevate boats over the
full 35-metre difference between the two canals, owing to the presence of the
historically important Antonine Wall, which was built by the Romans in the second
century AD. Boats travel under this wall via a tunnel, then through the locks, and
finally on to the Union Canal.
Questions 14-19
Do the following statements agree with the information given in Reading Passage 2?
In boxes 14-19 on your answer sheet, write
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