Clock on a so-called 'Vienna box', made of porcelain and painted with five women and three amors. Inside a landscape with houses.
World time
‘Everything is relative’ – even time. So goes the modern bromide. But humanity has spent thousands of years looking for better ways to measure time. Their practical usefulness was initially limited: when almost nobody owned a timepiece, everyone consulted the church clock. So what did it matter if it kept accurate time? So long as people hardly moved from home, it was no problem that every town had its own local time. Accurate, uniform time-keeping gained importance only with the arrival of the railways in the nineteenth century. Now we have atomic clocks and there is no way to tell the time more accurately. They are sent up on board the satellites used in GPS navigation systems. Even though we should remember that, according to Einstein, time in a moving satellite is also relative…