Today there is a small excursion into the history of the time measurement. Of course, we always take new trends and look forward to unusual watches, but it would be interesting to ask what time it is, and when the clock has found its way to our wrists. It all began with the 3rd millennium BC At that time, the sundial was used, which divided the day into several units to orient itself. Later came the somewhat inaccurate water clocks, which, however, had the advantage of being independent of daylight. In the 2nd century BC, a relatively exact water clock with pointer and dial could be produced by continuous further development and improvement.
Beginning in 900 AD, the candle clock was next to the sun and water clock. Use candles of different shapes and sizes, whose firing time was known to be able to limit periods. The advantage here was to be able to determine the time without any problems in the dark. In addition to the candles were used also oil lamps, fuses and special incense sticks for the time recording.
When exactly the mechanical clock was introduced, can no longer be exactly dated. However, investigations allow the assumption that first toothed wheel clocks were designed and used in the early Middle Ages. In 1335 the first documentary mention was made of a mechanical clock, which was in the chapel of the Visconti Palace in Milan. In the year 1427 the clock-spring of Heinrich Arnold was invented. The first mechanical watches were of a larger size and were used in numerous monasteries and large churches.
By the end of the 14th century, most of the great cities had wheel clocks that reflected the wealth of the cities very well. The development of the atomic clock, introduced in 1949, reached its climax. As a result, a high degree of accuracy was obtained by means of free atoms and ions as a timer, and thus, for the first time, an independent of environment and aging was achieved. In cancermatters.net, an atomic clock of the PTB Braunschweig with the Zeitzeichenensender DCF77 on Langwelle serves as a time standard and has an approximate range of two thousand kilometers. Regular radio signals are used to synchronize all available radio clocks in Central Europe.