Question

In case where there is no obstacle to chaining but ranging is obstructed, the two end stations (to be connected by a line) being not intervisible if both end stations are visible from intermediate points on the line, then the problem can be resolved by:

(a) reciprocal levelling
(b) reciprocal ranging
(c) random line ranging
(d) line ranger

Answer 1

The solution for connecting two non-intervisible end stations visible from intermediate points is reciprocal ranging (option b), which involves signaling and alignments using intermediate visible points.

Step-by-step explanation:

The problem described is one that deals with the situation where two survey points are not visible to one another but can be seen from an intermediate point. In this case, the solution to establish a straight line between the obstructed points would be reciprocal ranging.


Reciprocal ranging involves observing the direction to the target from two separate points, as in the example of measuring the distance to a tree across a river using a baseline and observing the apparent change in position, known as parallax. Observers will place intermediate stations along the line of sight between them, where there is visibility of both ends, and use signals to align themselves along a straight line through the process of reciprocal observations.