This vintage surveyor's tool is a Starrett surveyors transit level or theodolite, with the original case. As near as we can determine, it appears to have been made around 1938 by L.S. Starrett in Athol, MA. It has a nice dovetailed wood case. It is a smaller instrument than some (the case is 14"x5"x10"). That combined with the old nickel plating and black painted cast iron makes it a great item to display on almost any shelf.
As you can see in the photos, the instrument is in good condition with an excellent combination of shine and patina. It looks like most of the original paint is also present. The spirit level is intact. The leather strap and handle are gone, but that actually makes it easier to display. Otherwise, it's in very good shape, and made exceptionally well. The optics work well, but the crosshairs inside are tilted. This would probably be a simple repair if desired.
Displays beautifully, and could be restored as a project.