Although plenty of political and social movements espoused the ten-or-hundred-hour day, the hundred-minute hour, and the hundred-second minute, the most infamous was the French revolution.
[Henri] Poincaré believed in decimal time with all his heart, and when he joined the Bureau [des Longitudes] in 1893, he pushed decimalization of time hard.
Rising through the ranks of the Bureau, he went from secretary in 1893 to president in 1899, pushing the new and improved system all the way.
[I]n 1897, the Bureau debuted a compromised system. Each day would still have 24 hours. It was only the minutes and seconds that would get changed to hundredths of an hour and a minute respectively.
At home, people complained that they’d have to change everything from their watches to the navigational equipment of ships. Other governments were openly incredulous. Although a successful mathematician, physicist, engineer, and philosopher, Poincaré was a failure as a standardizer.