Transit theodolite parts 

1.  Telescope of theodolite: Telescope is mounted on a spindle or horizontal axis or Trunnion axis. Internal focusing type telescope is widely used. 

2.  Vertical Circle of transit level: Vertical circle is a circular graduated ring is attached to the horizontal. With the help of vertical circle, we can measure the vertical angle of the line of sight with the horizontal axis. 

3.  Index frame or T frame: Two verniers are fitted to read the vertical circle. The index frame is a T shaped frame consisting of a vertical leg known as clipping arm. It is also called a Vernier frame. 

4.  Transit level head: Transit level head consists of two parallel triangular plates. These triangular plates are called tribrach plates. 

5.  Plumb Bob: Plumb bob is used for the temporary adjustment of the theodolite. 

6.  Compass: Compass is used to measure the angle between the normal line and line of sight. 

7.  Tripod: Tripod the main part needed for a theodolite and it is used for supporting theodolite.