Theory
Ranging rod are made up of hollow pipes of steel. These are of circular cross section with of about 30 mm dia. Length available are 2 meter and 3 meter. They are divided into equal part each part having 0.2 long these part of rod are alternately red and white or blacks and white, so that they can be practical rod. White and black successive at bottom side of ranging rod iron show is provided to make it easier to be fixed into ground.
Uses
Ranging rods are used to fix position of station. To range various surveying lines.
Direct ranging
Ranging : It is the process of fixing the intermediate points on a straight line between two ends station.
Procedure
First ranging rods were fixed at end station i.e. A and B exactly in vertical position the survey was standing in between A and B. The survey placed his eye at the near ranging rod A and by looking the direction ranging rods B directed the assistant to move right or left with the help of hand sight. Finally when these rods where in a straight line the operation is over.
Diagram
Indirect ranging : it is type of ranging is also called as reciprocal ranging.
Procedure
It was done when the end of a line AB were not inter visible due to hilly ground.
First two intermediate points P and Q where fixed in such a way that from P. Both ranging rods at P and A were visible from P sight were given to rod so that it can in a straight line. Then from a point P was shifted in a straight line QA.
At last point AP, QB used in a straight line.
