Bote Holman set up the Knowledge Centre for Timekeeping museum CHRONOMIUM in Ootmarsum.
Here you find much concerning ancient clocks, tower clocks, and sundials.
A most charming example is a sundial of which about 8000 copies were manufactured in Germany, shortly after the Second World War, to be used as a pocket watch.
Floating horizontal sundial 1946 (production: 8000)
Plastic, 4 cm (1 ½ in), in cardboard box with manual.
Rüter Uhr Berlin
A small button in the bottom is pressed to “float” the sundial on a needle point. The sundial then self-aligns to magnetic north.
A small correction scale gives true north.
The gnomon provides the shadow for the time readout.
The marking is in true solar time, but the sundial has an additional scale for “summer true solar time”!