Metric system
In 1799 the metric system was made compulsory, meaning people were made to use it by law, in the region around Paris. This caused a lot of confusion because the police enforced the new measures but customers preferred the old ones. So shopkeepers had to have both. People became worried the new measures were used to cheat them. Politicians tried to educate and convince people to use metric, but the people rejected the metric system. In 1800 the government tried to make the system acceptable by changing the names of the units back to the simpler names used before metrication. For example, the decimetre, centimetre, and millimetre were renamed to palme (hand), doigt (finger) and trait (trace).