[Copper height arc quadrant]
The copper height arc quadrant was manufactured under the supervision of the Qing Palace Construction Office during the reign of Emperor Kangxi of the Qing Dynasty. The copper frame has a total height of 66cm and a radius of 66cm
The center of the instrument is equipped with a small cylinder perforated on four sides, which can be rotated. There is a vertical ear sight at both ends of the quadrant arc, and there is a central line on the vertical ear. The user adjusts the instrument so that the sun just falls on the central line of the vertical ear after passing through the thin seam of the cylinder. At this time, the thin seam of the cylinder and the central line of the vertical ear are in the same line with the sun’s light. The difference between the angular degree indicated by the central line of the vertical ear and the angular number indicated by the drop line (lost) is the zenith distance of the sun, and the zenith distance is reduced by 90 degrees to get the sun’s horizon height. A compass is embedded in the base plate of the instrument to correct the measuring direction
The instrument is of fine workmanship, and its base and plate are carved with western patterns and grass patterns. It is a representative work of measuring instruments made in the Qing Dynasty, and has been included in the book “The Imperial Ritual Instrument Pattern”
铜制测高弧象限仪