Earth North America

Where the high water-mark is required and the survey is made during a period of low water.

Value Step one,

Pair of Ranges.

Control Line One.

Control Line Two.

Control Line Three.

Control Line Four.

traverse on all the Topography.

Locke level

or

Clinometer

Elevation & Distance.

Locating Contours by the Hand

The work is done by making profiles of lines whose positions on the map are known

A point on a contour is found in the following manner.

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