a. Plate level
The plate level with protective glass is installed on the alidade bracket and is vertical to adjustment vertical axis unit. The level is obturated with plaster in the metal tube. There is a setscrew on the right of the metal base with an adjusting screw which can make the left of the level rise or fall so as to adjust the plate level axis vertical to vertical axis.
b. Circular level
As a primary leveling one, bubble of circular plate moves to the center directly after plate level is well adjusted.
