A discrepancy is a difference between two measured values of same quantity. A discrepancy may be small, yet error may be great if each of two measurements contains an error that may be large.

The chain line may be represented eir by a single line or by two lines spaced about 1.5 to 2 cm apart.

Check line is laid by joining apex of triangle to any point on opposite side or by joining two points on any two sides of a triangle. Each triangle must have a check line.

In soft ground, wooden pegs may driven, leaving a small projection above ground. The name of stations may be written on top.

The coast survey table is superior table. It is generally used for work of high precision.

The above symbol is standard conventional sign for grave. This symbol is used to represent grave in topographic map.

Dumpy level is used in levelling not in chain surveying. 20 m chain, arrows, pegs etc are mandatory for chain surveying.

Extended hand of surveyor implies that assistant should continue to move. Right hand of surveyor implies that assistant has to move right side.

Pedometer advantage on passometer is that it registers total distance covered unlike number of paces in passometer.

Type of surveying in which shape of earth taken into account is geodetic surveying. The survey which deals with bodies of water for purpose of navigation, water supply, harbor works or for determination of mean sea level is hydrographic surveying.