To provide a failureless permanent clock capable of telling the time of sunrise on the next day, of telling the variation of azimuths of the sun in a year, and of telling real north, south, east and west without using a magnetic compass as well as telling the time of the clock.

The sun is moving from a certain azimuth to another day by day. When it is considered in terms of date and time, the azimuth of the sun is the same throughout a year but has different positions depending on date and time. In the relationship among the different azimuth of the sun, date and time, if the relationship among them in a year can be read at a glance, when two out of the azimuth of the sun, date and time are clarified, the remaining one should spontaneously be determined. This application forms the relationship into a graphic diagram. Accordingly, using the application together with a magnetic compass realizes the permanent clock.