The one that was more surprising to me is the etymology of "seconds". They're called seconds because they're the second division of an hour (the first being minutes).
https://simple.wikipedia.org/wiki/Second#Trivia
One natural way of adapting this into English would be "terce" (like the religious service), although I guess we could also just call it a "third" -- about 17 milliseconds.
According to some stuff I was reading last week, this is just about the smallest time interval that a human being can learn to notice in many contexts, or just about the smallest timing accuracy with which a person can learn to react to an anticipated event. For example, it's about the timing accuracy needed for a frame-perfect action in a NES speedrun. So there is a human use for such a small time interval!
I wonder if people involved with early film and video had a lot of 60:1 gearing available because of clocks or something (or just thought it was a very intuitive division to use).
(In the UK the mains frequency is 50Hz, as is the standard TV refresh rate)