C/o a spectrometer table with two telescopes and one compensatory assembly, divided circle on the spectrometer table must have a diameter 190.0 mm divided to 20 min with vernier reading to 20 sec, two telescope objectives to contain 14.0 mm polarizing prisms mtd in vertical divided circles, divided circles to be 4.188 in. Diameter divided in degrees and reading to 0.1 degrees with a single ten part vernier