Surveying Equipment

The equipment used in leveling consists of a leveling instrument and a leveling rod. The most common type of level is called an engineer's or a dumpy level. The leveling instrument is a telescope containing both vertical and horizontal crosshairs and one or more spirit levels (bubble in a liquid-filled tube) to indicate when the instrument base is horizontal. The entire assembly, consisting of the frame, telescope and spirit level, can be "leveled" by turning the three or four leveling screws that hold the frame in position above the tripod head.

Another common level is the hand level. It usually has a spirit level for holding it horizontal and one set of cross-hairs. More sophisticated models may also have stadia hairs and direct reading angle scales.

The traditional leveling rod is a wooden scale about 1 inch by 2 inches in cross section and about 14 ft long, graduated in feet, tenths and hundredths of feet. Rods measuring in feet and inches, and meters and centimeters are also available. Rods are used to measure the vertical distance between the line of sight through the telescope and the object on which the leveling rod is resting.

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