Leveling bench mark on the ground

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Leveling bench mark on the ground (units are in
cm)
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• LEVEL RODS
• Level rods are made of wood, fiberglass or metal
  and have graduations in meters and decimals. Two
  main classes of rods are
• . Self reading rods, which can be read by the
  instrument operator while sighting through the
  telescope and noting the apparent intersection of
  the cross wire on the rod. This is the most
  common type.
• . Target rods having a movable target that is set
  by a rod person at the position indicated by
  signals from the level operator.
• Rods with two graduations are used in precise
  levelling, These rods provide the elimination of
  reading and estimation errors by having a
  constant number between two graduations. Using
  these rods also provide two parallel loops in the
  same leveling line with an increase in accuracy.

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Precise levelling rod (with two graduation lines)
Simple rod
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1.234 m
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Ground plates for levelling rods
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Levels Levels have the capability of scanning an
horizontal plane, which is perpendicular to
vertical, after the set of the bubble. When
rotating the level around the vertical axis,
level should cover an horizontal plane by means
of bubble or automatic compensator, which is a
very common technology used in levels by using
simple rule of pendulum balance as used in
teodolites. Levels with automatic compensators
are also called automatic levels which are self
levelling instruments that can provide a
reduction in measuring time by 30 to 40.
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Axis of level (tangent at midpoint)
Radius of curvature 20 sensitivity angle
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Automotic level (Kern GK1-A)
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Tilting level (Kern N41)
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Precise level with micrometer (Wild N3)
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Precise level with micrometer (Wild Koni 007)
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Automatic level with micrometer (Zeiss Ni1)
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River crossing instruments
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