'Hours' in the Bible

Jesus answered, Are there not twelve hours in the day? If any man walk in the day, he stumbleth not, because he seeth the light of this world.

And it was about the space of three hours after, when his wife, not knowing what was done, came in.

But when they knew that he was a Jew, all with one voice about the space of two hours cried out, Great is Diana of the Ephesians.