The dumpy level is an optical surveying instrument used to determine relative elevations and distances of points in a survey. It consists of a telescope secured by collars and spindles to a horizontal stage. The telescope can only rotate horizontally. Dumpy levels are used to measure heights and distances between locations. They have simple construction, require few adjustments, and retain accuracy over time due to rigidity. However, they can be difficult for engineers to use accurately and are not as easy to operate as other instruments.