The western wall of the nave c.1190 and c.1380. (Figs. 178-180)
On the extreme left and right the photograph (Fig.178) shows the end of the Anglo-Norman arcade c.1177. It then shows portions of the East-West arches of the western transept c.1190, and then, in the central area, the central part of the west wall of similar date.
The window is described
by Reilly (1998, 92) as “a large lancet window now filled with perpendicular
tracery.” From c.1190 to c.1380 the window space would most probably have been
filled with perhaps three narrow lancet windows, possibly surmounted by a
circular window. The present
Perpendicular tracery is almost certainly contemporary with the Perpendicular
porch c.1380. In style it is not unlike
the N.E. chapel window at Cheddar, (viz.
The photographic distortion of the west window and its correction.
It is possible to estimate from Fig. 178 the position from which this photograph was taken. This is possible by examining the angle of view through the arches on the left. We find that the camera was about 75 feet from the west wall.
The west window glass stands approximately six feet six inches further to the west than the wall surface (Fig. 179). A passage about three feet wide at triforium level passes between the lower wall surface and the window wall. The window glass stands about three and a half feet into the window wall, which is about five feet thick. The total thickness of the whole wall at pavement level is therefore about eight feet, for it is in fact formed from two walls, one c.1180, belonging to the west transept, and the other c.1220, part of the great portal development.
These dimensions have been arrived at by perspective projection. The extra distance of the window from the camera has reduced the apparent size of the window by 5%. Furthermore, the angle at which the photograph has been taken has caused the window to appear to stand two feet two inches lower than in reality (Fig. 179).
In order to correct these distortions the size of the window has been increased by 5%, and the enlarged image of the window has been raised by two feet two inches. This brings the window image to appear as if it were in the same plane as the wall surface (Fig. 180).