I and my colleagues were able to measure both the horizontal and vertical angle of land(From 0° to 360°) with the use of surveying telescope which is usually fixed onto the engineer's level and is used to sight the levelling staff. My eye was placed behind the eyepiece and focuses the telescope on the levelling staff, which is some distance away. The light rays, originating at the staff passes into the telescope through the object glass and in the process are inverted for underground work in mines! The rays continue through the telescope and are captured as an image on a glass disc called the reticule. A series of lines are etched on the reticule and the lines were seen together with the images of the staff and readings were taken!