Plumb Bob:

It is generally heavy spherical or conical ball, as display in Figure 2(d), of metal and is used to transfer points on ground through suspending it along with the help of a strong thread. It is used for measuring distances at the sloping ground by stepping. Compass, Dumpy stages and Theodolites are also positioned over the station point accurately along with the help of plumb bobs.

Line Ranger:

A line ranger consists of either two plane mirrors or two right angled isosceles prisms that was placed one above the other as depicted in Figure(e). The diagonals of both the prisms are silvered so as to reflect the incident rays. Line rangers are given along with a handle to hold the instrument. A line ranger could also be used to draw offset on a chain line.