In order to obtain higher measured accuracy of star's positions by the low-latitude meridian circle, it is needed to measure the astronomical refraction to the stars of different spectral types.
提出在低纬子午环上，对不同光谱型的天体测定出天文折射，以提高星位测定的精度。
2
Sacrifice Circle Model is not a universal explanation about the compositions of the local society, for it not only neglects the historical latitude, but also the influence of other factors.