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5.5 Leveling Equipment
There are several types of surveying levels and level rods. Some are meant
primarily for precise leveling work, and others are much better suited for ordinary
construction and operation of the various types of leveling equipments, so as to be
able to select and use the best instrument for a particular surveying assignment.
Compared with a transit or theodolite, the level is a relatively simple instrument.
It is only required to give a horizontal line of sight in all directions of the compass,
and this is easily accomplished using basic optical and mechanical components.
A surveying level basically consists of a telescope and a sensitive spirit bubble
vial. The spirit level vial can be adjusted so that, when the bubble is centered, the
line of sight through the telescope is horizontal. The telescope is mounted on a
vertical spindle, which fits into a bearing in the leveling head. The leveling head
may have either three, or two leveling screws, depending on the type of instrument.
The most common types of levels are the dumpy level, the tilting level and the
automatic level. A transit or theodolite may also be used for leveling work,
although the accuracy obtained is generally less. A simple hand level may be used
for determining the elevations when a high degree of accuracy is not required.

Fig 5.3 Dumpy level

Fig 5.4 Tilting Level
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