Errors in prime vertical-meridian observations and some suggestions

I discuss the effects of instrumental errors on the absolute determination of azimuth a and latitude φ by means of combined prime vertical and meridian observations. The analysis shows that the single-star measuring accuracy of a is much higher than that of φ . In order to obtain an independent, high-accuracy declination system as early as possible, I suggest first to carry out absolute declination measurement of stars in a selected declination zone and use these stars to determine the equator point of the graduated circle. I suggest also that single observation should be more fully utilized.