Instrument required
1. Theodolite
2. Ranging rod
Diagram
Procedure
The instrument of settle over the station ‘P’ as usual and ‘Q’ was bisected accurately point ‘R’ was establish in the line of sight beyond ‘Q’. The instrument was shifted to ‘Q’ station. ‘R’ was bisected and point ‘S’ was establish in the line of sight beyond ‘R’. The process was repeated till station ‘X’ reached.