The large stone octagonal tower, with its eight internal archways, leads up to timber vaulting that appears to allow the large glazed timber lantern to balance on their slender struts. The roof and lantern are actually held up by a complex timber structure above the vaulting which could not be built in this way today because there are no trees big enough. The central lantern, also octagonal in form, but with angles offset from the great Octagon, has panels showing pictures of musical angels, which can be opened, with access from the Octagon roof-space, so that real choristers can sing from on high. More wooden vaulting forms the lantern roof. At the centre is a wooden boss carved from a single piece of oak, showing Christ in Majestry. The elaborate joinery and timberwork was brought about by William Hurley, master carpenter in the royal service.