divided into twelve double hours the arc of the heavens comprised a full circle of 360 degrees hence one Barrow or double hour represented 30 degrees of the arc of the heavens by this method passage of time on earth provided a measure of the distances in degrees between the named celestial bodies the third method of measurement was Barrow Enosh ami length in the skies after o dangun pointed out that while the first two methods were relative to other phenomena this third method provided absolute measurements a celestial Barrow