To tell whether a given point is on a ridge or in a valley, start from the nearest stream shown on the map and work across the map to the undetermined point, keeping in mind that in a real trip across the country you start from the stream, go up the hill to the top of a ridge, down the other side of the hill to a water-course, then up a hill to the top of a ridge, down again, up again, etc.  That is all traveling is—­valley, hill, valley, hill, valley, etc., though you wander till the crack o’ doom.  And so your map travels must go—­valley, hill, valley, hill—­till you run off the map or come back to the starting point.

On the map, follow the R-V line, V indicating valley and R ridge or hill.  Note first the difference in sharpness in the contour bends; also how the valley contours point to the highland and the ridge contours to the lowland.

The contours go thus: 

[Illustration]

The streams flow down the valleys, and the sharp angle of the contour points always up stream.  Note also how the junction of a stream and its tributary usually makes an angle that points down stream.

“Which way does this stream run?”

Water flows down hill.  If you are in the bed of a stream, contours representing higher ground must be to your right and to your left.  Get the elevations of these contours.  Generally the nearest contour to the bank of the stream will cross the stream and there will be an angle or sharp turn in the contour at this crossing.  If the point of the angle or sharp turn is toward you, you are going downstream; if away from you, you are going upstream.

If the contours are numbered, you have only to look at the numbers to say where the low and where the high places are; but to read a map with any speed one must be quite independent of these numbers.  In ordinary map reading look, first of all, for the stream lines.  The streams are the skeleton upon which the whole map is hung.  Then pick out the hilltops and ridges and you have a body to clothe with ail the details that will be revealed by a close and careful study of what the map maker has recorded.

As to closed contours, they may outline a depression or a hill.  On the map, “881” or “885” might be hills or ponds, as far as their shape is concerned.  But, clearly, they are hills, for on either side are small streams running away from them.  If they were ponds, the stream lines would run toward the closed contours.  The rest of “hill, valley, hill,” will always solve the problem when there are not enough stream lines shown to make evident at once whether a closed contour marks a pond or a hill.  Look in the beginning for the stream lines and valleys, and, by contrast, if for no other reason, the hills and ridges at once loom up.

To illustrate the subject of contours to aid those who have difficulty in reading contoured maps the following is suggested: