[duchenne]

All measurements used to be a mess: lengths, weights, and so on. At the French revolution, they broke the status quo by introducing the metric system. Originally, the metric system also included a new calendar:

- One day has 10 hours.

- One hour is divided in units of 10, 100, 1000 (probably deci/centi/milli hours).

- One week has ten days.

- Each year starts at the fall equinox.

This calendar was used for 14 years. Then, Napoleon decided to bring back the previous calendar system as he reintroduced Catholicism as a state religion. Indeed the revolution calendar was purposely anti-christian: it moved the first year from the birth of JC to the year of the French revolution. Several religious events like Easter were hard to compute. Christmas was the day of the dog...

Anyway, we could have got a calendar system that makes sense, but History decided otherwise.