Grating Form of the Micrometer of A Low-Latitude Meridian Circle (Ⅱ)

By following the article I¹, the problem about the adoptable form is further discussed of the grating of the micrometer attached to a low-latitude meridian circle in this article. The grating is composed of slant, vertical and horizontal slits. It meets the needs of the observation carried out by means of the new method for absolutely determining a star in the prime vertical and meridian directions. There is no need to revolve the position angle q of a star during the observation of it by turning the horizontal axis of the meridian circle at 180° and the standards of the precision of machining of some parts of the instrument can be lowered.