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5.6 Leveling Procedures
A. Setting Up and Leveling the Instrument
The level must be securely mounted on top of a three-legged wooden or
aluminum stand called a tripod. Two basic types include an adjustable-leg tripod
and a fixed-leg tripod. The adjustable leg model is convenient for setups on steeply
sloping ground and is more easily transported when closed. The fixed leg type is
more rigid and provides greater stability for precise leveling work. The instrument
is either screwed directly on to the tripod head or attached with a fastening-screw
assembly.

Fig. 5.8 Tripod stands

Fig. 5.9 Tripod head adaptor
Each leg of a tripod has a pointed metal shoe at the end. The tripod is setup with
the legs well spread and pressed firmly in to the ground. If the surface is hard or
paved, each tripod leg should be placed in a crack in the pavement; the leg hinges

may also be tightened for extra friction.

B. Leveling a Three-Screw Instrument
Three leveling screws first approximately level some tilting levels and nearly
all-automatic levels. The level position is indicated by the coincidence of a spirit
bubble and 'bull's-eye' of a circular level vial. Any one of the three screws can be
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