In 1800, Paris enacted an ordinance banning women from wearing trousers. The law was technically enforced until 2013, with amendments in 1892 and 1909 allowing trousers only while holding bicycle handlebars or horse reins.
In 19th-century Paris, all city clocks were synchronized via compressed air. Around 300km of underground pipes carried minute-by-minute pressure pulses from a central master clock to over 4,000 clocks. When the 1910 Paris flood hit, every clock in the city froze at 10:53 AM.