Limb divided 0-45° every 1° with transversals to 10' that can be read to 1' with the aid of the chamfered edge of the alidade. Limb also divided 45-90° and 90-45°. In upper portion of octant, an engraved right triangle serving as a sinical quadrant with sides calibrated 0-100 every 1.
Material
".C.T.D.E.M. 1[6]18" on alidade sight vane, whose window cut away the "6"
