THEODOLITE

an instrument used in ronomical work and in land surveying, measure angles in either a horizontal rertical plane. It consists of a telescope, which is attached a graduated circle, ich rotates in a vertical plane. The scope is supported Bpoe &@ graduated “le, which rotates in a horizontal! plane. ¢ telescope can thus be turned towards; point, and the angles through which it as read off from the circles, The in strunt is ides with a compa and rit lovels, to a ist in arranging it in “ition [s. 298]