Royal copper-plated star dial

[Imperial copper-plated star dial]

The imperial copper-plated star dial was made in the fifty-third year of the reign of Emperor Kangxi of the Qing Dynasty (1714) by the Qing Palace Office, with a height of 21.5 cm and a diameter of 11 cm. The old collection of the Qing Palace
This star dial is an instrument for finding time by measuring stars. It is divided into upper and lower discs. The upper heavy plate is called the Heavenly Plate, with 24 solar terms carved around it. An inverted triangular straight table is set at the upper end of the sky plate. The two star names of “Gouchen” and “Emperor Star” are carved on the left and right sides of the back of the table, and the three words “Two Star Table” are carved in the middle. A handle is attached to the lower end of the celestial disk. The lower heavy plate is called the site. One side is carved with twelve hours around the circumference, the other side is carved with twelve hours around the outer circumference, and the inner circle is carved with one, two, three, four, and five hours around the center. Twenty-four throttle meters and horizontal and vertical lines are symmetrically carved around the center. The horizontal line is the throttle line, and the vertical line is the change line. A drop line is installed in the center hole of the astrolabe for straightening
This instrument can not only measure the time, but also get the time. The method of use is to take the plumb line straight, and the surveyor turns the celestial disk, so that the two ends of the triangular straight table on the disk marked with “Gouchen” and “Dixing” are aligned with the two stars “Gouchen” and “Dixing” in the northern celestial pole, respectively. The solar term indicated by the plumb line on the celestial disk corresponds to the time on the site, which is the desired time. In order to find the time, the solar term obtained from the star measurement corresponds to the time line on the horizon, and then the corresponding time is found from the time line, which is the time and time
The sky plate is engraved with the inscription “Emperor Kangxi 53 years” and the handle is engraved with the inscription “Emperor Kangxi”
The production of this star dial is based on the design principles of similar western instruments, and also incorporates the traditional Chinese timing method. It has its own uniqueness.