Ten Degrees of Daylight

In the book of 2nd Kings, Chapter 20 in the Bible, we're told of a King Hezekiah of Judah, who had fallen gravely ill. The king prays for God to heal him or remember his works for the Lord, and God sends his prophet Isaiah to tell him that he will extend his life by fifteen years. When the king asks what sign shall he look for that what the prophet says is true, Isaiah tells him that the shadow on the sun dial will retreat ten degrees backwards. This is a record of events from that day.