[Aardwolf]

Since they had this mechanism, did they also have regular clocks with gears in ancient times?

According to Wikipedia, they only had that kind of clocks since the middle ages, but if they were building a mechanism with gears to keep track of other planets in ancient times, surely they must also have done so for local time?

[johnhenry]

One important distinction between a clock an the mechanism is that clocks can be would up and run "by themselves". Perhaps this was the missing key? (Though, this would not preclude them from creating "mills" run by wind/water to display time.

Another thing to consider is that the concept of doing things at a specific time may not have matter to much of the worlds population at the time and, even though they were capable; there was no demand.