9781422287859

10 Surviving with Navigation & Signaling

large scale and shows every detail of the land if they are traveling a distance of over thousands of miles. This may seem obvious, but it is a mistake many people make. Understanding maps Maps contain a vast quantity of information. Soldiers do not ignore this immense amount of detail at their fingertips. They learn how to make the most from it. Some of the crucial features, keys, and symbols they need to learn are listed below: • Contours — show the height of the land. The intervals may be in yards, with the approximate value in meters indicated in the margin. • Legend—explains what the symbols on the map mean. The symbols are not always the same on every map. It is therefore important for the soldier to refer to the legend of whichever map he is using, which is located in the margin. • Bar scales—rulers used to convert map distance to ground distance. Maps usually have three or more bar scales, each a different unit of measurement, such as miles and kilometers. The scales are located in the margin. • Contour interval—states the height distance between contour lines on the map. This is located in the margin. • Black topographic symbols—point out man-made features, such as roads, buildings, and pipelines. They are also used to show rock features. • Blue topographic symbols—point out water features, such as lakes, oceans, rivers, and swamps; they also indicate freeways. • Green topographic symbols—point out vegetation , such as woods, forests, and vineyards. • Brown topographic symbols—show all relief features, like contours.