Compass surveying is a surveying technique used to measure the survey lines by determining the angles using a compass and linear measurements by using a chain.


What is the principle of Compass Surveying?

The principle of compass surveying is traversing. Traversing is the method of locating a series of survey line in the form of a network by placing survey stations one after another. The previously surveyed station is used as the base to measure the next point.
The traverse can be either open traverse or closed traverse.

Also Read: What is Principle of Surveying?

What is the unit of measurement in a Compass in Compass Survey?

The units of angle measurement is performed by:
  1. Sexagesimal System 
  2. Centesimal System
  3. Hours System
Most commonly used system is Sexagesimal System. The centesimal system is used in Europe. Hours system is used for astronomical purposes.

In Sexagesimal System , 1 Circumference is 360 degrees of arc, with 1 degree=60' (minutes of arc) and 1 minute = 60'' (seconds of arc).

What compass is used for Compass Surveying?

The two main types of compass used in compass surveying are Prismatic compass and Surveyor's Compass. 

How to notate bearings in Compass Survey?

The bearings can be represented by:

  1. Whole circle bearing system (W.C.B) or Azimuthal System 
  2. Quadrantal Bearing System (Q.B) or Reduced Bearing

Whole circle bearing system (W.C.B) or Azimuthal System 

In WCB system:
  1. Bearings are measured from North magnetic meridian only.
  2. Measured in clock-wise direction.
  3. W.C.B of any line lies between 0 to 360 degrees
  4. It is implemented in Prismatic Compass

Whole circle bearing system (W.C.B) or Azimuthal System 

Quadrantal Bearing System (Q.B) or Reduced Bearing

Quadrantal Bearing System (Q.B) or Reduced Bearing

In Q.B system:

  1. Bearings can be measured either from North or south whichever is near.
  2. Measured clockwise or anti-clockwise
  3. The bearings obtained lies between 0 and 90 degrees
  4. It is implemented in Surveyor's Compass
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