Maps have been used by humans for hundreds of years. As technology has improved, so have the quality and accuracy of maps. Ancient maps were usually drawn by explorers. It was impossible at that time for anyone to leave the Earth and look down at the huge continents below. All they could do was walk around the different land formations, and then do their best to draw what they thought the land probably looked like.
In the modern world, our ability to view and map the Earth is much improved. However, even today it is impossible to draw a flat map that is 100% accurate. This is due to the impossibility of recreating the surface of a round planet on a flat map. The smaller an area that a map represents, the more accurate that map will be.
The Key To Understanding Maps
Maps can be drawn to represent a variety of information. This information might include things such as roads, tourist attractions and campgrounds, or they might represent the latest weather patterns. The objects on a map are represented using symbols. A symbol is a picture on the map that represents something in the real world. Understanding these symbols requires the use of a key. Maps use a key, or legend, to explain the meaning of each of the symbols used in the map. These keys usually show a small picture of each of the symbols used on the map, along with a written description of the meaning of each of these symbols.
Drawn To Scale
Remember that a map is a visual representation of a much larger area of land. In order to be useful, a map must by necessity be small enough to be handled by an individual. Imagine drawing a map of the Earth that was full-size. Of course this is ridiculous. A full-size map of the Earth would not only be too large to be useful, but it would also be impractical to make. Maps are scaled down so that they fit on the available paper or screen. When scaling down a map, every part of the map is scaled by the same amount. This insures that every object on the map is the same proportion as everything else on the map. If a city is twice as large as a neighboring town, an accurate scaled map will show the same relationship on paper. The drawn city will be twice as large as the drawn town.
Because the Earth is round and maps are flat, it is impossible to create a map with a perfect scale. Some parts of the map will be too large, while others will be too small. The larger a territory represented by a map, the greater that the distortions in scale will be.
It is important that we recognize how to read, understand, and utilize scale as we examine the various maps that we encounter. There are three common methods used by map makers to depict scale. These methods are referred to as the graphic method, the verbal method, and the fractional method.
The Graphic Method
A Graphic Scale depicts scale using a line, with separations marked by smaller intersecting lines, similar to a ruler. One side of the scale represents the distance on the map, while the other side represents the true distances of objects in real life. By measuring the distance between two objects on a map and then referring to the graphic scale, it is easy to calculate the actual distance between those same items.
There are many benefits to using a graphic scale. First and foremost, it is a straight forward, easy way to determine scale. Secondly, if a map’s size is enlarged or decreased, the scale is also enlarged or reduced, meaning that it is still accurate.
The Verbal Method
The verbal method of depicting scale simply uses words to describe the ratio between the map’s scale and the real world. For example, a map might say something like, “one inch equals one hundred and fifty miles.” Calculating scale on a map using the verbal method is easy. Simply measure the distance on the map and then follow the verbal directions to calculate the actual distance.
The Fractional Method
The fractional method for portraying the scale of a map uses a representative fraction to describe the ratio between the map and the real world. This can be shown as 1:50,000 or 1/50,000. In this example, 1 unit of distance on the map represents 50,000 of the same units of distance in the real world. This means that 1 inch on the map represents 50,000 inches in the real world, 1 foot on the map represents 50,000 feet on the map, and so forth.
Large Scale Map Versus Small Scale Map
A map which depicts a small territory is referred to as a large scale map. This is because the area of land being represented by the map has been scaled down less, or in other words, the scale is larger. A large scale map only shows a small area, but it shows it in great detail. A map depicting a large area, such as an entire country, is considered a small scale map. In order to show the entire country, the map must be scaled down until it is much smaller. A small scale map shows more territory, but it is less detailed.
Globes Help Us Understand Our Planet
Globes have a very important role in helping us understand the shape of our home planet. Because globes are the same shape as the Earth, it is possible to create very accurate globes. We do not have to worry about the distortion that occurs when round continents are flattened out so that they fit on flat maps.
Despite their usefulness, globes have many disadvantages as well. The biggest of these disadvantages is due to the fact that globes represent the entire Earth. Because of this, they will always be small scale representations of the Earth. This means that it is difficult to show very much detail on a globe. Only the largest objects can be depicted, such as the largest lakes and rivers. Smaller lakes, streams and hills simply cannot be shown. Another disadvantage of a globe is that their awkward size and shape makes them difficult to carry around. Imagine trying to fit a globe inside of a glove box, or in your back pocket. Globes are an important tool that geographers use, and that students should study. However, flat maps are much more practical for use in everyday situations.
