According to Max Clarke this item was used by the surveying classes at the Ballarat School of MinesA boxed (timber) theodolite with crossbars and full-length stadia wires. The theodolite can be mounted on a metal straightedge base. The box also contains a magnetic compass with two bubble levels, a plumbing folk, and 4 brass paper clips designed to suit a plan table. On box in black paint "A 1". Inside box lid is manufacturer's label and Stadia measurement zero reference calibration.ballarat school of mines, surveying equipment, gurley, max clarke, theodolite, stadia measurement, calibration, scientific instrument