The chapel originally had a nave, chancel and an apsidal sanctuary. This is called perihelion precession or apsidal precession. The nave columns are high, and the apsidal windows are . Later Romanesque chapter houses sometimes had an apsidal eastern end. Newton's theorem of revolving orbits was his first attempt to understand apsidal precession quantitatively. Newton derived an early theorem which attempted to explain apsidal precession. It consists of an apsidal hall with stupa. It consists of an apsidal hall with a stupa. The plan described for each include square, octagonal and apsidal. Fire altars and apsidal structures were revealed in Rakhigarhi. In the adjunct image, Earth's apsidal precession is illustrated. However, Newton's theorem is more general than merely explaining apsidal precession. The Shrine of Saint Cuthbert was located in the eastern apsidal end of the cathedral. The window is located to the right of the entrance to the apsidal chapel. The central dome is surrounded by eight apsidal semi-domes like the petals of a flower.