SECTION 1
READING PASSAGE 1
You should spend about 20 minutes on Question 1-14 which
are based on Reading Passage 1 below.
Timekeeper:
Invention of Marine Chronometer
A
Up to the middle of the 18th
century, the navigators were still unable to exactly identify the position at
sea, so they might face a great number of risks such as the shipwreck or running
out of supplies before arriving at the destination. Knowing one’s position on
the earth requires two simple but essential coordinates, one of which is the
longitude.
B
The longitude is a term that can
be used to measure the distance that one has covered from one’s home to another
place around the world without the limitations of naturally occurring baseline
like the equator. To determine longitude, navigators had no choice but to
measure the angle with the naval sextant between Moon centre and a specific
star— lunar distance—along with the height of both heavenly bodies. Together
with the nautical almanac, Greenwich Mean Time (GMT) was determined, which
could be adopted to calculate longitude because one hour in GMT means 15-degree
longitude. Unfortunately, this approach laid great reliance on the weather
conditions, which brought great inconvenience to the crew members. Therefore,
another method was proposed, that is, the time difference between the home time
and the local time served for the measurement. Theoretically, knowing the
longitude position was quite simple, even for the people in the middle of the
sea with no land in sight. The key element for calculating the distance
travelled was to know, at the very moment, the accurate home time. But the
greatest problem is: how can a sailor know the home time at sea?
C
The simple and again obvious
answer is that one takes an accurate clock with him, which he sets to the home
time before leaving. A comparison with the local time (easily identified by
checking the position of the Sun) would indicate the time difference between
the home time and the local time, and thus the distance from home was obtained.
The truth was that nobody in the 18th century had ever managed to create a
clock that could endure the violent shaking of a ship and the fluctuating
temperature while still maintaining the accuracy of time for navigation.
D
After 1714, as an attempt to find
a solution to the problem, the British government offered a tremendous amount
of £20,000, which were to be managed by the magnificently named ‘Board of
Longitude’. If timekeeper was the answer (and there could be other proposed
solutions, since the money wasn’t only offered for timekeeper), then the error
of the required timekeeping for achieving this goal needed to be within 2.8
seconds a day, which was considered impossible for any clock or watch at sea,
even when they were in their finest conditions.
E
This award, worth about £2 million today, inspired the
self-taught Yorkshire carpenter John Harrison to attempt a design for a
practical marine clock. In the later stage of his early career, he worked
alongside his younger brother James. The first big project of theirs was to
build a turret clock for the stables at Brockelsby Park, which was
revolutionary because it required no lubrication. Harrison designed a marine clock
in 1730, and he travelled to London in seek of financial aid. He explained his
ideas to
Edmond Halley, the Astronomer
Royal, who then introduced him to George Graham, Britain’s first-class
clockmaker. Graham provided him with financial aid for his earlystage work on
sea clocks. It took Harrison five years to build Harrison Number One or HI.
Later, he sought the improvement from alternate design and produced H4 with the
giant clock appearance. Remarkable as it was, the Board of Longitude wouldn’t
grant him the prize for some time until it was adequately satisfied.
F
Harrison had a principal
contestant for the tempting prize at that time, an English mathematician called
John Hadley, who developed sextant. The sextant is the tool that people adopt
to measure angles, such as the one between the Sun and the horizon, for a
calculation of the location of ships or planes. In addition, his invention is
significant since it can help determine longitude.
G
Most chronometer forerunners of
that particular generation were English, but that doesn’t mean every
achievement was made by them. One wonderful figure in the history is the
Lancastrian Thomas Earnshaw, who created the ultimate form of chronometer
escapement—the spring detent escapement—and made the final decision on format
and productions system for the marine chronometer, which turns it into a
genuine modem commercial product, as well as a safe and pragmatic way of
navigation at sea over the next century and half.
Questions 1-5
Reading Passage 1 has seven
paragraphs, A-G.
Which paragraph contains the
following information?
Write
the correct letter, A-G, in boxes 1-5 on your answer sheet.
NB You may
use any letter more than once.
1
a description of Harrison’s background
2
problems caused by poor ocean navigation
3
the person who gave financial support to
Harrison
4
an analysis of the long-term importance of
sea clock invention
5
the practical usage of longitude
Questions 6-8
Do the following statements agree
with the information given in Reading Passage 1?
In boxes 6-8 on your answer sheet, write
TRUE
if the statement is
true
FALSE
if the statement is
false
NOT GIVEN if the information is not given in the passage
6
In theory, sailors can easily calculate
their longitude position at sea.
7
To determine longitude, the measurement of
the distance from the Moon to the given star is a must.
8
Greenwich Mean Time was set up by the
English navigators.
Questions 9-14
Complete the sentences below.
Choose NO MORE THAN TWO WORDS AND/OR A NUMBER from the passage for each
answer.
Write
your answers in boxes 9-14 on your
answer sheet.
9
Sailors were able to use the position of the
Sun to calculate ……………………
10
An invention that could win the competition
would lose no more than ……………………. every day.
11 John
and James Harrison’s clock worked accurately without ………………………….
12 Harrison’s
main competitor’s invention was known as ………………………….
13
Hadley’s instrument can use …………………………. to
make a calculation of location of ships or planes.
14 The
modem version of Harrison’s invention is called ……………………………
ANSWER
1. E
2. A
3. E
4. G
5. B
6. TRUE
7. FALSE
8. NOT
GIVEN
9. local
time
10. 2.8
seconds
11. lubrication
12. (a/the)
sextant
13. angles
14. marine
chronometer
PASSWORD: Realexam20
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