Reports have reached me that the conservation of medieval windows in Lincoln Cathedrals below the "Bishop's Eye" window will begin in 2013.
A press report is here
Tom Kupper gives additional information for people more involved with stained glass: "Proposed conservation of four medieval stained glass windows at Lincoln Cathedral Considering the environmental impact and vulnerability of unprotected medieval glass attention has now been turned on the conservation and preservation of four medieval lancet windows underneath the magnificent Bishops Eye rose window in the south west transept of Lincoln Cathedral, England. The Lincoln cathedral glazing department has visually monitored these historic windows for several years in terms of deterioration and the rate of corrosion. After a routine survey it was found that the glass is continuing to decay and not being protected from the external environment by a protective glazing system the historic glass is baring the full brunt of the Lincolnshire weather, airborne corrosive pollutants and lately some mindless vandalism. So much so that one of the medieval lancets has been the subject to some mayor damage in 2008 with an intruder breaking out of the cathedral smashing a sizeable hole through the historic glass. This laughable action has brought the four lancets firmly back into focus and a condition survey of the windows was carried out. In assessing the vandal damage the glazing department swiftly established that any restoration cannot just deal with the damaged panel in isolation and one ought to consider conserving the entire lancet. Which in turn highlighted the fact that once the conservation project is off the ground the other three reaming lancets also need to be taken into consideration and bought into a program too? The glazing department is now proposing, for the four medieval windows underneath the Bishops Eye rose to go through a full conservation and preservation cycle which, because of its complexity, could last up to 4 years with an estimated total cost of £550 000. However, before the windows can undergo the conservation processes there are several key issues which we need to be discussed before a conservation policy can be writing. 1. Restoration of the vandal damage within the central area in one of the lancets. 2. Conserve the four medieval lancets, the historic ferramenta and the original oak timber frames and keeping the three elements together. 3. Establish a pre & post monitoring research program by investigating the environmental conditions in and around the area of the windows. 4. Protect the lancets with an internally ventilated glazing system and finding a visually acceptable external finish for the protective glass. 5. Form an Anglo-German research partnership to investigating the chemical makeup of the historic glass and to search for appropriate cleaning techniques specifically designed for the four lancets. These five key points all raise of course several more separates philosophical and ethical issues which need to be further addressed by the Dean and Chapter’s approval committees before the project becomes live in 2013."