Sundial "Hora C" made of Thuringian Porcelain with Inner Clock for Well-Being (Ø 15,5 cm)

Note: This sundial is set to latitude 50° N and can therefore be used within Germany with sufficient accuracy. It is also suitable for other regions near this latitude.

This sundial combines its astronomical function with the biological concept of the internal clock. This is not esotericism, but a scientifically sound concept that earned three American researchers the 2017 Nobel Prize in Medicine. The internal clock regulates human body temperature, blood pressure and hormone secretion – three important factors for our everyday well-being and the restfulness of sleep. Sunlight, with its varying colour and intensity depending on the time of day and season, has the greatest influence on the internal clock.

It is therefore obvious to relate the solar time indicated by the sundial to the inner clock. Thus, with this sundial, one can find one's own natural and harmonious rhythm for physical activities, work, meals and sleeping.

The clock therefore shows the essential bodily processes of our biological daily rhythm in the inner area with clear symbols, called circadian rhythm in chronobiology. The symbols are surrounded by a rough classification of the inner clock with factors such as blood pressure, attention or body temperature. The outermost ring shows the solar time (independent of modern time). For evaluating the findings of one's own inner clock, the sundial comes with a self-awareness sheet.

It also comes with a compass for aligning the sundial to the north and with a detailed manual. A metal holder including screws and dowels for fixing the sundial is also supplied on request.

Thanks to its first-class manufacture from high-quality materials, the sundial is suitable for both indoor and year-round outdoor use. It is manufactured in the traditional family-run Thuringian porcelain manufactory Rudolf Kämmer in Rudolstadt, Germany. The coloured scale is fired into the porcelain at 800 degrees. Ceramic solid colours are used in a screen-printing process. The central hemisphere and the shadow thrower are made of stainless steel. The sundial is water- and scratch-resistant as well as weather- and frost-resistant.

This sundial is available in another version, which shows clear symbols of the internal clock instead of the astronomical representation of the sunlight (see below).

This sundial was developed by engineer Carlo Heller who began to learn astronomy and design sundials as a young schoolboy. As a mechanical engineer, he was later able to produce sundials with minute-accurate readings using laser manufacturing processes and optical measuring technology. His sundials are not gimmicks, but highly competent reinterpretations of an ancient cultural technique of timekeeping. Some of his models have been presented to foreign guests of state of Germany many times as a demonstration of skillful German engineering. The sundials are manufactured exclusively in Germany.