Question

What is the function of the plumbing fork in plane table surveying?

Answer 1

Plumbing Fork:

A plumbing fork is a U-shaped piece of the metal frame. It is used for the centering of the plane table over the station.

One end of the frame is pointed and is kept over the drawing sheet touching the plotted position of the instrument station while the other end of the frame carries a plumb bob.

The position of the plane table is adjusted until the plumb bob hangs over the station occupied by the instrument.