Leveling is a branch of surveying which aims to find the distance from the ground of a given point with the data provided so that you can establish a point at a given altitude. Leveling instrument is an instrument developed to set up a horizontal line of sight and spirit level is used to develop the horizontal line. Spirit level, the dumpy level, the digital level and the laser level are the most commonly used leveling instruments.
Spirit Level (Bubble level)
To indicate whether a surface is level or plumb spirit level or Bubble level is used. Original spirit levels are comprised of two bananas shaped curved glass vials at each point of view. They are little complicated in structure. The spirit level will be placed in such a way that the tripod in between two points and the height difference between those points can be calculated easily. To mark the points markers in rock or soil are used. A leveling rod equipped with measured graduations is placed on each point. The focus of the viewer will be pointed on each road and values can be calculated from it. Calculate the difference of back and forward value to find the height difference.
Dumpy level (Automatic Level)
Automatic level is an optical instrument used in surveying and building. It helps to transfer measure or set horizontal levels in surveying and building. A dumpy level is an older style instruments and skilled use is necessary to set that instrument correctly. The instrument should be set level in each quadrant, so that full 360 degree traverse is accurately maintained. Some dumpy levels will have bubble level to ensure accuracy and perfection. A benchmark with known height determined in previous survey, or an arbitrary point with an assumed height can be used to calculate the measurement.
Digital level is a leveling instrument in surveys which use a special rod scale so that the height can be calculated. Data recording competence is a major feature of Digital level. The computerization tries to eliminate the job of operator to read a scale and so it reduces blunders that can happen to a great extend. Refraction and curvature corrections can be done with the help of this instrument. The bubble level vial, spirit level vial and laser technology are some important features supporting digital level.
The laser level is affixed to a tripod, leveled and then spun to illuminate a horizontal plane in leveling and surveying.The laser beam projector is comprised of rotating head with a mirror. Visually readable level vials and physically adjustable screw to adjust the projector is equipped in laser level to provide better performance.