Retro Clock

None of the first clocks survive from 13th century Europe, but various mentions in church records reveal some of the early history of the clock.
The word horologia was used to describe all these devices, but the use of this word (still used in several Romance languages) for all timekeepers conceals from us the true nature of the mechanisms. For example, there is a record that in 1176 Sens Cathedral installed a 'horologe' but the mechanism used is unknown. According to Jocelin of Brakelond, in 1198 during a fire at the abbey of St Edmundsbury (now Bury St Edmunds), the monks 'ran to the clock' to fetch water, indicating that their water clock had a reservoir large enough to help extinguish the occasional fire.

probably from Celtic (cf. O.Ir. clocc, Welsh cloch "bell") and spread by Irish missionaries (unless the Celtic words are from M.L.); ultimately of imitative origin. Replaced O.E. dægmæl, from dæg "day" + mæl "measure, mark."
- Online Etymology Dictionary

When you want to set your clock, what source do you use? Internet, TV news? And where do they get the right time? From some of the existing atomic clock An atomic clock is a clock that uses an electronic transition frequency in the microwave region of the electromagnetic spectrum of atoms as a frequency standard for its timekeeping element. Atomic clocks are among the most accurate time and frequency standards known, and are used as primary standards for international time distribution services, to control the frequency of television broadcasts, and in global navigation satellite systems such as GPS.