The sundial was made in 1780 by the church painter Joseph Anton Morath in the eastern municipal buildings by the spa gardens.
It not only marks the time but also the respective month. Chronos, the god of time, is depicted, holding the time band in his right hand and the gnomon in his left. A characteristic feature is the vertical figure of eight which makes the sundial a so-called “midday clock”. At the end of the gnomon “con Chronos”, the figure of eight is met by a perforated disc enabling it to pass across the corresponding date – that means it is 12 noon in St. Blasien (local time). This device used to regulate the mechanical church clock in the cathedral’s bell tower.