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Obstacle to chaining and ranging - Obstacle to chaining but not ranging
Obstacle to chaining and ranging
Obstacle to chaining but not ranging
There are two types of obstacle in this case
- When it is possible to chain round the obstacle. E.g., pond.
- When it is not possible to chain round the obstacle. E.g., river
Select two points A and B on either side (Fig(a)). Set out equal perpendiculars AC and BD. Measure CD; then CD=AB.
II Method
Set out AC perpendicular to the chain line (Fig(b)). Measure AC and BC. The length AB is calculated from the relation.
Set out AC perpendicular to the chain line (Fig(b)). Measure AC and BC. The length AB is calculated from the relation.
Last modified: Friday, 29 April 2011, 8:39 AM