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Tough
painting—water color—sketch
Local government
Localization
Greece
Mathematics
Base
Footnote
Forehead
philosophy
Commonly—ordinarily
Classic
Flat—apartment
Flat tyre
Refer to---referee
Navy—log—voyage—sailor
Calculation—calculator
Fixed
In line with—out of line with
Rely on / upon
LESSoN EIGHTEEN
TEXT B
Why Are Maps Drawn1 with North at the Top
Now it is hard to visualize2 a map that does not feature north at the top, but this was not always so.
The oldest known map in the accepted sense of the word was drawn about 3,800 BC, and represents the river Euphrates flowing through northern Mesopotamia, Iraq. This, and others that followed it, were little more than rough sketches3 of localized features; it was not until many centuries later that the ancient Greeks placed the science of map-making on a sound footing.
At the forefront of the pioneers in the field was the Greek mathematician4 and philosopher Claudius ptolemaeus (c. AD 90-168), more popularly known to history as ptolemy. The last great scientist of the classical period, he was the first to draw a map that was based on all available knowledge, rather than guess or imagination. Earlier, the Babylonians had attempted to map the world, but they presented it in the form of a flattened5 disc rather than a sphere, which was the form adopted by ptolemy.
Given the state of knowledge of those times, he got things wrong; for example, his estimate of China and the Atlantic ocean was far from being accurate. Nevertheless, it was a useful effort, and the map remained a work of reference for over a thousand years. In fact, Christopher Columbus used a version of it when he set sail in search of the New World -- which caused him some navigational problems, since ptolemy had calculated wrongly the size of the Atlantic and was unaware6 that the pacific ocean existed.
The really important thing about ptolemys map was that north was at the top. The reason for this was that he decided7 to orientate8 the map in the direction of the pole Star since polaris was the immovable guiding light in which the voyagers of that era placed their trust.
North at the top remained the accepted arrangement until the early Middle Ages, when the Church began to interfere9 seriously with the advance of science. In accordance with the orders of the Church, maps were still produced in accordance with ptolemys principles -- but now Jerusalem was the central feature, as it was held to be the center of the Christian10 faith, and east was moved to the top.
These maps are often called T Maps because they show only three continents -- Europe, Asia and Africa -- separated by the T formed by the Mediterranean11 Sea and the River Nile. From a navigational point of view, they were almost useless.
More accurate maps began to appear in the 14th century, with the spread of trade and increasing reliance on the compass. once again, north assumed its rightful place at the top of maps.
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