Ways of time-measurement?

[Errand-Rider Karigan]

Yet a mention of time is made by Gandalf in the Fellowship of the Rings, book two, the first chapter, Many Meetings:

"Where am I, and what is the time?" cried Frodo, sitting up. There was an old wizard, sitting in a chair by the open window.

"In the House of Elrond, and it is ten o'clock in the morning" said a voice...

So clearly time means something.