Why image on theodolite upside down?

The image seen through a theodolite appears upside down due to the use of a system of prisms and lenses in the instrument. These optical components invert the image as it passes through, a common feature in many optical devices. This inversion allows for precise measurements and alignment, as the user can easily correlate the view through the theodolite with the actual physical layout of the surveying area. Ultimately, this design helps maintain accuracy in reading angles and distances.