The Savile Chapel window at Thornhill : project update

Ruth Cooke, Jonathan Cooke, David Martlew & Paul Bingham


The 15th century York glass of the Savile Chapel at Thornhill Parish Church is in an advanced state of deterioration.   A project to conserve the window has been initiated, but the prognosis is problematic.   The condition of the window raises issues about how, if at all, it might be conserved, and presents a number of ethical dilemmas for those charged with its care.
Sarah Fearn and Laurianne Robinet applied state-of-the-art analytical techniques to study attack on vulnerable glass surfaces by moisture vapour in the atmosphere.   Their results suggested to us that attack by water vapour seems the probable cause of the deterioration of much of the glass in the Savile chapel windows.

A set of six sensors has been deployed to study the ambient conditions faced by the east window.   These have been in place for six months, and early results will be presented.   Together with a chemical analysis of a small fragment which became detached from one of the severely degraded pieces of glass, we hope that these measurements will contribute strongly to planning the conservation strategy.   Physical, chemical, aesthetic and ethical issues will be explored, and the audience will be invited to comment.


Jonathan Cooke ACR has been fascinated by the play of light through stained glass for as long as he can remember. At the age of sixteen, he began a four year apprenticeship at York Minster, and has worked in stained glass ever since, with a special interest in researching ancient techniques and recipes for glass painting. Since 1987, he has been in private practice as a stained glass conservator and artist. He is the tutor for short courses in glass painting at Swansea Metropolitan University and the University of York, and has been invited to run a similar course in New Jersey in October 2010. He serves on the Stained Glass Committee of the Council for the Care of Churches, and several Diocesan Advisory Committees. Ruth Cooke's work as half of this stained glass conservation team includes stained glass audits for grant and other purposes. She is working with the client as project manager at Thornhill and is enjoying the involvement with the glass science community this project has generated since her initial presentation at Lancaster last year.