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Fig. 4.4. A plumb bob: (is one of the
simplest yet most important

accessories for accurate surveying) Fig. 4.5. A surveyor’s range pole

When a transit or theodolite is not used to establish direction, range pole serve
to establish a line of sight and keep the surveyors properly aligned. A range pole
would be placed vertically in the ground behind each endpoint of the line to be
measured.
Steel taping pins are used for marking the end of the tape, or intermediate
points, when taping over grass or unpaved ground. Taping pins are most useful for
tallying full tape lengths over long measured distances.

Fig. 4.6. (a) Chaining pin (b) Keel
When taping horizontal distances, it is necessary to hold the tape as close to a

horizontal position as possible. In order to reduce errors caused by an excessively

sloped tape, some surveyors make use of a hand level. A horizontal line of sight

can be easily obtained by looking through the level towards the surveyor at the

higher end of the tape

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