Let's recap the things that we have discussed. First the terminology, then the process, and finally a few helpful pointers. If at any point during this review you have other questions, would like to step through the process again, or want to see example map images, use the navigation buttons at the left to review the section of choice. TERMINOLOGY Contour Interval ~ the distance between each contour line Intermediate Contour ~ a brown line on a topographic map and represents a line of equal elevation Index Contour ~ a bolder/wider brown line that has the elevation value marked at various intervals as a part of the line Supplemental Contour ~ a dotted or dashed line that represents half the interval between the other contour lines Depression Contour ~ a contour that indicates a hole and is represented by a "hachured" brown line PROCESS Determine the contour interval, either through calculation or by looking at the bottom center of the map Find the index contour nearest the item that for which you want to determine the elevation Determine the direction of slope (uphill or downhill) based on another index contour or by analyzing the area around the "point in question" Count the contours between the index contour and the location for which you need to know the elevation; count either by contour interval or multiply the contour interval by the number of contours counted Determine if the point for which you wish to know the elevation is situated on a contour or between contours and determine the elevation accordingly. HELPFUL POINTERS Water features are always lower than the adjacent and nearby areas. This should help you when determining the direction of slope. When contours cross a stream or deep valley, the form a "V" shape where they cross. The "V" points to higher elevations. The closer contours are together, the steeper the slope. The further apart contours are, the flatter the terrain. Supplemental contours may be used on flatter terrain. When a point does not fall directly on a contour, interpolate the elevation between the contours, either to one-third, one-half, two-thirds or possibly in quarters, depending on the contour interval and the distance between the contours. Spot elevations are helpful when determining direction of slope, highest contour, and exact elevations of points.
	Now that you have had time to review the material, go on to the practical exercise. The practice exercise asks questions similar to the ones through the various steps. You should answer each question on a piece of paper and, when you have answered each question sufficiently, click on the "Show Answers" button at the end of the quiz. Check you work, review any problems you missed, and email any questions to Lisa Keys-Mathews. GOOD LUCK!
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