Prof. Tom Regan
LIB200.6501
Rezwana Islam
2/16/2016
The Shape of the World: The Secrets of the Sea
Latitude and Longitude:
Imaginary lines on the earth’s surface, enabling any point to be defined in terms
of two angles. Parallels of latitude are circles drawn round the earth parallel to the
equator; their diameters diminish as they approach the poles. These parallels are specified
by the angle subtended at the center of the earth by the arc formed between a point on the
parallel and the equator. All points on the equator therefore have a latitude of 0 degree,
while the north pole has a latitude of 90 degree N and the south pole of 90 degree S.
Parallels of latitude 1dagree apart are separated on the earth’ surface by about 100 km
(Credo Reference).
Meridians of longitude are half great circles passing through both poles; they
cross parallels of latitude of right angles. In 1884 the meridian through Greenwich, near
London, was selected as the prime meridian and the given the designation 0 degree.
Other meridians are defined by the angle between the plane of the meridian and the plane
of the prime meridian, specifying whether it is E or W of the prime meridian. At the
equator meridians 1 degree apart are separated by about 112 km (Credo Reference).
This movie shows the bribery and international power struggle around the world
to search for gold, spices and gain control of the rest of the world. Gaining power over
others was the main reason of why people started discovering the world. During the 14th
century in the competition to dominate the seas, China held the lead. 100 years later the
great empire of Portugal was the first in the race to sail around Africa, only to be closely
challenged by Venice and later by Spain to find the spices, and the gold that will increase
their power and wealth. These nations would stop at nothing not even murder.
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Prof. Tom Regan
LIB200.6501
Rezwana Islam
2/16/2016
Under 500 years ago the ocean divided the earth into several unconnected world.
No one made the link between the different land and seas. So, whoever took the first step
would acquire wealth, this temptation lead people discovering the world. The knowledge
of the ocean was first learned by Portuguese sailors.
Chinese were ahead of Europe in the art of navigation. They invented the compass
(Feng Shui). In 1400’s Chinese were the masters of the sea. The Chinese thought they
had everything for themselves (knowledge, all the products), they didn’t want anything
from outside because the whole world was theirs. If anyone was caught going abroad,
they would be punished. Even though compass was already known in China, but it was
not used for navigation.
Literary evidence proves that the compass arrived in Europe at the end of the 12th
century. The compass is an instrument for finding direction based on the property of a
magnetic needle of settling on a north-south line. The needle swings on a central pivot
above a disc marked with the cardinal points. A ship’s compass hung on gimbals will
maintain its horizontal position in spite of the movement of the ship. The compass card,
showing the desired direction of the travel, completes the instrument. Compass was a
revolutionary discovery of science. Before the invention of compass, people used to get
lost through darkness and fog over the unmarked oceans. As pointed by Frederic C. Lane
the winds and clouds of the Mediterranean made the compass important in the sea
especially in connection with winter navigation. In the article named The Economic
Meaning of the Invention of the Compass Frederic C. lane mentions “probably the chief
economic importance of the compass in the Mediterranean was that it led to more
voyages per year. In transportation between Venice and the Levant, being at sea in winter
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Prof. Tom Regan
LIB200.6501
Rezwana Islam
2/16/2016
months made all the difference between two voyages a year instead of one. It enabled
ships to transport twice as much each year and keep crews more continually
employed”(610). So, apart from any effects it may have had on navigation in the China
seas, the use of the compass aided the quickening of transportation in two important
respects: more and safer voyages from the Mediterranean to the English Channel and
more movement of shipping in the Mediterranean during the winter. The invention of the
magnetic compass made navigation possible and the sailors used the same trembling
needle to guide their ships through darkness, rain, and fog and over the unmarked ocean.
The art of navigation nowadays is applied to travel over the oceans as well as to travel in
the air. As mentioned by Captain J.P. Ault in his article named Methods of Sea and Air
Navigation, “the methods of navigation, the means used in determining the ship’s
position, its latitude north or south of the equator and its longitude east and west of the
meridian of Greenwich, are for the most part based on the same elementary principles
which have been used since the time of Columbus” (60). This example shows how
longitude and latitude helped human development and prosperity in terms of travel and
map making. The radio compass is the most important contribution to the science of
navigation since the invention of the magnetic compass. If the captain of a ship is
approaching a harbor, he can send out a radio signal, and the men at the different radio
compass station on shore can determine the direction of the incoming signal by slowly
rotating the large loop-antennas of their radio compass until the signal is loudest. The
observers than “radio-wave” back to the captain his direction from their respective
stations. By plotting these bearings on his chart the captain can very quickly and
accurately locate his position, and this performance can be repeated as frequently as
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Prof. Tom Regan
LIB200.6501
Rezwana Islam
2/16/2016
desirable in spite of clouds, fog or darkness. From these articles and the movie, we
understand we are where we are because of this great invention. Traveling is now only a
plane or ship fare away. Import, export businesses are not as hard as it used to be.
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Prof. Tom Regan
LIB200.6501
Rezwana Islam
2/16/2016
Works Cited
Ault, J. P. “Methods of Sea and Air Navigation”. The Scientific Monthly, Vol. 22, No. 1.
(Jan, 1926), pp.60-63.
Burke, James. “The Shape of the World: The secret of the Sea”. PBS video.
Lane, Frederic C. “The Economic Meaning of the invention of the compass”. The
American Historical Review, Vol. 68, No. 3. (Apr, 1963), pp. 605-617.
“Latitude and Longitude.” The Macmillan Encyclopedia. 2007. 26th September.
http://www.credoreference.com.
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Prof. Tom Regan
LIB200.6501
Rezwana Islam
2/16/2016
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Prof. Tom Regan
LIB200.6501
Rezwana Islam
2/16/2016
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