Dumpy levels, Theodolite, and Laser levels. Aims and objectives To identify the differences between the above items To successfully measure point in a classroom using a dumpy level and laser level. To identify the markings on the graduation staff and how it is read. Dumpy levels/ Automatic levels  A dumpy level/automatic level, is an optical levelling instrument used in surveying to transfer measurements or to set horizons. Line of sight  The level instrument is set up on a tripod and, depending on the type, either roughly or accurately set to a levelled condition using foot screws (levelling screws). The operator looks through the eyepiece of the telescope while an assistant holds a tape measure or graduated staff vertical at the point under measurement. The instrument and staff are used to gather and/or transfer elevations (levels). Measurement generally starts from a benchmark with known height determined by a previous survey, or an arbitrary point with an assumed height. Practical Time Laser Levels    This rotating laser beam takes the place of a construction worker having to sight through the telescope of an optical level in order to record a level along the collimation axis. The laser beam representing the collimation axis is received by a sensor that can be attached to the levelling staff. This sensor is able to slide up and down the levelling staff and an audible tone is heard to indicate how close to the collimation axis the sensor is. When the sensor is moved toward the collimation axis the intermittent tone will increase in frequency, until a constant tone is heard when the sensor and axis are at the same height. Many instruments will provide a different sounding tone, to indicate the direction of travel required. Practical Time Theodolites    A Theodolite is an instrument used for measuring in both the horizontal and vertical angles. A modern Theodolite consists of a movable telescope mounted within two perpendicular axes—the horizontal or trunnion axis, and the vertical axis When the telescope is pointed at a desired object, the angle of each of these axes can be measured with great