When visiting the Leiden city hall, one finds a small staircase, seemingly leading to nothing, with a small black handle and a line etched into the wall. In fact, these three objects once had a large historical significance. The staircase was known as the shouting platform, where the mayor, duke or lawmen would announce important things or place verdicts upon convicts. The other two objects are the official standards for the old Dutch length measure, called the Rhineland Foot.
Why would you need a standard measure in a city? Because it is necessary for most professions and trade. It is very hard to trade properly without having an exact measurement that is agreed upon. A famous example is when cloth sellers would have their daughters or wives measure and cut the fabric because their thumb (inch) is shorter than that of the traders.
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