Can levelling be done on a theodolite?
Yes, and it is a basic demand that the instrument itself be accurately leveled- there are built in spot and cylilndrical levels on true theodolites- as well as plumb bobs on the older instruments, and optical plummets to establish the vertical on modern ones. the theodolite, the quintessential engineering instrument is a highly refined variant of the simpler surveying Transit. Non-optical transits existed in Classical times and it is certainly plausible the word itself came from an approximation of the Greek- The Eye of God- for Theodolite- There are all different types- it can get very mathematically involved. There are some specialty types such as the spot-averaging theodolite which can be used in motion studies of such objects- as -and one emphasiszes from a safe distance, the dimensions of tidal waves. The spot-averaging mechanism is similar to a movie camera but takes only two shots a second over a two-minute period and strikes a mechanical average- used also for aircraft and subm
