2 Kings 20:10

And Hezekiah answered, It is a light thing for the shadow to go down ten degrees, if it would merely advance ten steps, this would not seem so very extraordinary; nay, but let the shadow return backwards ten degrees, returning through the space which it had already traversed. If we suppose the sun-dial to have consisted of a column surrounded with circular steps, the shadow at noon striking the highest step in the center, and in the morning and evening the lowest step on either side, we have some idea of how it worked.