When were clocks used for the first time in science?

Question

Time has been mechanized already by sundials. These nails and chains that are banged in and put around time have been increasingly refined to accumulate in the advent of the atomic clock. So-called Natural units were even invented. Without mechanized time the world would have looked very different. Maybe we have some kind of marshmallow minds. Maybe we could better wear aikhornnuts on our wrists as Krznaric puts it.

When were the first mechanized timekeepers used in science? Was Galileo the first one? Did this use further science a lot? So newer means and more precise keepers could be constructed?

Answer 1

Water clock is also a kind of "mechanized clock", and it can be very sophisticated. There is a strong evidence that in ancient Babylon and Greece they were used in science, namely for astronomy. In Ptolemy, we can read records of some astronomical events, like lunar eclipses, which happened during a night, and their time is recorded to a fraction of an hour (like 1/2 or 1/3 of an hour). This indicates that a water clock probably had to be used to time them. What else? Ptolemy mentions water clock only once in his book, (Chap. V, sect 14) only to say

"Of all methods of this investigation... we rejected those using water clock...since these methods are not sufficiently precise"

This seem to indicate that other investigators did use them.

Edit. From the Wikipedia article cited above, I learned that Herophilos used a clepsydra to measure the pulse rate of his patients, which can be also considered as "scientific purpose". The same article mentions several astronomers who constructed and used clepsydras.

As I said, Ptolemy was not satisfied with the accuracy of clepsydras for astronomical purposes. Weight driven clocks of the Middle age were not more accurate. The first breakthrough in accuracy came when Galileo invented the first clock regulator, that is the pendulum.