Levelling is the art of determining the relative elevations of different objects or points on the earth's surface. This is done by taking measurements in the vertical plane. Hence, this branch of surveying deals with measurements in vertical planes.

Levelling deals with vertical measurement

Levelling is a fundamental process in surveying that deals with the measurement of vertical distances or elevations between points on the earth's surface. It is an important technique used in civil engineering, construction, and other fields where accurate elevation measurements are necessary.

Levelling involves the use of a levelling instrument, which is a type of optical instrument that measures the difference in height between two points. The instrument consists of a telescope mounted on a tripod, and a levelling staff or rod, which is a graduated rod that is used to measure elevations.

Levelling is done in a vertical plane

During levelling, the instrument is set up on a known elevation, and the rod is held at the point where the elevation is to be determined. The telescope is then pointed at the rod, and the height of the rod is read from the graduations on the staff. This height is then compared to the height of the instrument, and the difference in height between the two points is calculated.

Levelling is typically done in a vertical plane, which means that the instrument and the rod are both held in a vertical position. This is necessary in order to ensure that the measurements are accurate and reliable.

Conclusion

In conclusion, levelling is a technique used in surveying and civil engineering to measure vertical distances or elevations between points on the earth's surface. It involves the use of a levelling instrument, which is used to measure the difference in height between two points in a vertical plane. Levelling is an important process that is used in a wide range of applications, from construction and engineering to mapping and land surveying.

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