| Module 10 Location of details |
To prepare a topographic map, a network of control points in a plane coordinate system get plotted in a sheet of paper as discussed in Module 9. Within the frame of control points, it is required to plot in detail the objects and features present on the surface of the earth. The usefulness of the final topographic map fulfilling the purpose of survey depends largely on the location of the details. Usually, topographic details are located by the same method as adopted for plotting of contours (Lesson 17). In carrying out the work, electronic surveying system or transit stadia or plane table can be used. The electronic system provides location, distance and elevation of desired object/ point simultaneously. So, if available, it is advantageous to employ this device for any kind of topographic survey. The transit stadia system is used where plenty of details are required to be located or where ground-cover limit visibility and require number of set up. But, in case of small scale mapping or when the area to be mapped is small or open or many irregular lines are to be mapped, plane table surveying is being adopted. Objective of Module 10 Objective of module 10 is to explain the plane table method of surveying for location of details.
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