How to Use a Map Page 3
Measuring Distance
As stated earlier, the scale of the map determines how much of the earth's surface is covered by a particular map sheet. In the case of the 1:24,000 scale, a distance of 1 inch on the map equals 24,000 inches (2000 feet or .38 miles) on the ground. So, measuring the number of inches between two points on the map can be converted to feet on the ground by multiplying the number of map inches by using this formula:
ground feet = map inches x 24,000 12
example: 2.5 map inches = 5000 feet
(2.5 x 24,000) = 60,000 = 5,000 feet 12* 12*
*The 12 comes from the fact that there are 12 inches in one foot.
An easier way to measure this distance (without math) is to take the measurement (2.5 inches in our example) and transfer that measurement to the bar scales. If you want the distance in feet, use the feet bar scale, miles for miles and kilometers for kilometers.
Take a close look at the feet bar scale. You will see that is does not start at zero, but at 1000. Move to the right on the scale and you will get to zero, then to 1000, 2000, and so on. To use the scale correctly:
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Go to Page 1,2,3,4,5,6,7,8,9,10,11 Look for books and equipment for Land Navigation in the Mercantile
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