Ways of time-measurement?

[Voronwe]

They had clocks. At least, Bilbo did, as this quote from The Hobbit shows:

'If you had dusted the mantlepiece, you would have found this just under the clock,' said Gandalf

I can't recall any other mentions of clocks being used anywhere else in Middle Earth. A clock in the Shire was probably considered a rare luxury, affordable only by richer hobbits such as Bilbo.