Geography For Dummies. Jerry T. Mitchell

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      Disputed paternity

      A Greek named Eratosthenes (died about 192 B.C.) is sometimes called the “Father of Geography” since he coined the word “geography.” The Greeks themselves called Homer the “Father of Geography” because his epic poem, Odyssey, written about a thousand years before Eratosthenes was born, is the oldest account of the fringe of the Greek world. In addition to these gentlemen, at least two other men have been named “Father of Geography,” all of which suggests a very interesting paternity suit. But I digress. That the story goes back to the days of the Greeks tells us that geography is a very old subject. This is not to say that others, say Arabs or the Chinese, were not also thinking about how to describe Earth. People of every age and culture have sought to know and understand their immediate surroundings and the world beyond. They stood at the edges of seas and imagined distant shores. They wondered what lies on the other side of a mountain or beyond the horizon. Ultimately, of course, they acted upon those speculations. They explored. They left old lands and occupied new lands. And as a result, millennia later, explorers such as Columbus, Magellan, and others found humans almost everywhere they went.

      Links to exploration

      

Geographers from ancient Greece through the 19th century were largely devoted to exploring the world, gathering information about newly found (to them!) lands, and indicating their locations as accurately as possible on maps. Sometimes the great explorers and thinkers got it right, and sometimes they did not (see the sidebar called “Measuring the Earth”). But in any event, geography and exploration became intertwined; so, “doing geography” became closely associated with making maps, studying maps, and memorizing the locations of things (see Chapters 3 through 5 for information on locating things and creating and reading maps).

      … To modern discipline

      During the past two centuries, and especially during the past several decades, geography has blossomed and diversified. Old approaches that focused on location and description have been complemented by new approaches that emphasize analysis, explanation, and significance. On top of that, satellites, computers, and other technologies now allow geographers to record and analyze information about Earth to an extent and degree of sophistication that were unimaginable just a few years ago.

      

MEASURING THE EARTH

      In the third century B.C., the Greek scholar Eratosthenes made a remarkably accurate measurement of Earth’s circumference. At Syene (near Aswan, Egypt), the sun illuminated the bottom of a well only one day every year. Eratosthenes inferred correctly this could only happen if the sun were directly overhead the well — that is, 90° above the horizon. By comparing that sun angle with another one measured in Alexandria, Egypt, on the same day the sun was directly overhead at Syene, Eratosthenes deduced that the distance between the two locations was one-fiftieth (1/50th) of Earth’s circumference. Thus, if he could measure the distance from Syene to Alexandria and multiply that number times 50, the answer would be the distance around the entire Earth.

      There are diverse accounts of the method of measurement. Some say Eratosthenes had his assistants count camel strides (yes, camel strides) that they measured in stade, the Greek unit of measurement. In any event, he came up with a distance of 500 miles between Syene and Alexandria. That meant Earth was about [500 x 50 =] 25,000 miles around (“about” because the relationship between stade and miles is not exactly known). The actual circumference is 24,901 miles at the equator, so Eratosthenes was very close.

      Interesting fact: The circumference is 41 miles less pole to pole; more on that in Chapter 4!

      About a century-and-a-half later, another Greek named Posidonius calculated Earth’s circumference and due to differences in the lengths of Roman versus Greek stadia, others reported his measurement as 18,000 miles. Posidonius’ measurement became the generally accepted distance mainly thanks to Strabo, the great Roman chronicler, who simply did not believe that Earth could be as big as Eratosthenes said it was. About 18 A.D. Strabo wrote his Geography, which became the most influential treatise on the subject for more than a millennium. Geography credited the calculations of Posidonius and rejected those of Eratosthenes. And that leads to an interesting bit of speculation. Columbus was familiar with Geography, so he was aware of the official calculation of Earth’s circumference — 18,000 miles. Had he known the true circumference was 25,000 miles, like Eratosthenes said, Columbus would have known that China was thousands of miles farther to the west than Strabo suggested. And if he had known the true distance to China, would Columbus ever have set sail?

      Geography is a widely misunderstood subject. Many people believe it’s only about making maps, studying maps, and memorizing locations. One reason is that polls and pundits occasionally decry the “geographic ignorance” of Americans, which usually means the average person doesn’t know where important things are located. Presumably, therefore, if you memorize the world map, then you “know geography.” Another reason is that on many TV quiz shows, contestants are occasionally asked “geography questions.” Almost always, the answer is a fact that can be understood by studying a map and/or memorizing the locations of things or events.

      Knowledge of the location of things is important and useful. Everything happens somewhere; and if you know the where, then the event has meaning that it otherwise would not. So map memorization is cool, but you need to keep it in perspective. Memorizing locations is to geography what memorizing dates is to history, or what memorizing the multiplication table is to mathematics. Namely, it’s a foundation — a base — upon which you can build and develop deeper understandings.

      

Have you ever asked an English professor if they know the 26 letters of the alphabet? Of course not! It’s silly. But care to guess how many times I have been asked to rattle off a list of state or country capitals? It’s equally as silly. Just as letters build words, and then words build sentences, and then those sentences become ideas to share, so too are places. For a geographer, places are like our alphabet, a starting point to explain the complexity of Earth. The bottom line is: There is more to geographic awareness than where something is. As other geographers have stated, we need to think about where, why there, and why we should care.

      Geographers still make maps and study them, and certainly, geography still consists of subject matter that cries out to be memorized. But map memorization and descriptive studies take a back seat to analysis, explanation, and significance. Geographers have a unique lens by which they try to understand Earth, and this approach comes with several advantages.

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