|right ascension: angle parallel to the celestial equator, measured eastwards from the spring equinox.
|ring dial: simple form of altitude dial in the shape of a ring, for use in one latitude.
|rule (or ruler): an instrument of multifarious functions in the form of a straight rod of metal, wood or other material; a folding rule is an alternative form with two or more jointed legs.
|Saints' days: anniversary days for Christian saints.
|scaphe dial: sundial where the hour lines are marked on a concave hemisphere or part hemisphere.