Obituary: Stephen Rees Jones

Stephen Rees Jones trained a generation of paintings conservators at the Courtauld Institute of Art in London. He was Head of the Technology Department of the institute for 25 years, from 1951 to 1976.

His most important legacy is the establishment of formal postgraduate training in paintings conservation which he achieved just before his retirement. This consolidated irreversibly the transformation of a profession which had relied on traditional apprenticeships, instating academic values, a spirit of learning and self-criticism and a multidisciplinary approach combining elements from science, art history and fine arts.

Born in 1909, he was educated at Flintshire Grammar School, and studied Physics at the University College of North Wales at Bangor. In 1935 he became a research assistant at the newly created Scientific Department of the Courtauld Institute of Art where he worked with W.G. Constable, D.V. Thompson and others laying the foundations for technical studies of the arts.

During the Second World War he went to work for the Ministry of Aircraft Production. He returned to the Courtauld Institute after the war and in 1951 became Head of the Technology Department. He was very much the lone scientist in an institute dedicated to art history but he began to engender in the art history students an appreciation of the material nature of paintings. This was sometimes a daunting task since there were few textbooks or experts to turn to and the students frequently had very little grounding in science.

In the main, his information came from the technical examination of paintings which was gradually developing during this period. Microscopy, technical photography, emission spectrography and X-radiography were his principal tools. Even the most impractical undergraduates received the experience of seeing a painting through a binocular microscope and came away acutely conscious of the delicacy of its surface.

The methods of examination developed at the Courtauld, the National Gallery and elsewhere have transformed our understanding of paintings. Rees Jones undertook systematic X-radiography of the paintings that came into the department and in this way extended the scope of connoisseurship to otherwise invisible aspects of paintings. He collected a useful group of fakes and copies for study purposes and a small museum of pigments. He built X-ray diffraction equipment for the analysis of crystalline pigments. He had to be resourceful and the accumulation of a body of knowledge was a slow process. Gradually there developed a wider appreciation of what was being achieved and interest grew. Rees Jones was then able to attract students to investigate conservation problems such as the action of solvents on paintings and better methods of lining. He built the first hot-table for the wax-lining of canvas paintings, an important innovation.

He also played a part in the formation of the main professional bodies of conservation, the International Institute for Conservation of Historic and Artistic works (IIC) in 1950 and its UK group, now the UKIC.

The value of his work became evident to a wider audience during the cleaning controversy of the 1960s. Renewed interest in the removal of discoloured varnish, in particular through the work of Ruhemann at the National Gallery during the 1940s and 1950s, led to a fierce dispute. Rees Jones was able to provide a balanced and objective view that was also independent of the National Gallery. His contribution to the debate helped to dispel some of the wilder allegations and helped focus on the scientific issues, in particular the potential for leaching of low molecular weight material from the paint film by the action of cleaning solvents.

All this work was carried out at 20 Portman Square. The Technology Department was confined to the bottom of the garden in the former coach-house and stables. There Rees Jones pieced together a complex of tiny studios and laboratories where his enthusiasm and imagination could flourish undisturbed. Training in conservation was at first on an ad hoc basis; only a few students could be taken. Eventually the course became more secure with a small but regular intake. Then, in 1976, it finally became a full three-year postgraduate diploma course and Rees Jones was acknowledged with a Chair Emeritus. By his retirement the work of his department had reached its highest standard, in particular the research that was so much needed by the new profession.

His department continues to flourish and Rees Jones, following his retirement to Sussex, continued to publish arcane but interesting calculations, for instance, on the optics of paint films or the diffusion of moisture in wood. He was also Professor of Chemistry at the Royal Academy of Arts, an honorary post that involved a series of lectures to art students.

Stephen Rees Jones will be remembered fondly by his students for his enquiring mind and the enthusiasm that he brought to his subject. He was a smiling, diminutive figure, unpredictable but never unreliable. When students became too tiresome and a discussion too involved he had the knack of disappearing through one of the many interconnecting doors in the department. No one knew exactly how he managed to slip away but the message was clear - think out problems for yourself: an important lesson for aspiring conservators.

Stephen Rees Jones, art conservationist: born Holywell, Flintshire 1 September 1909; married 1939 Margaret Laffineur (died 1994; two sons); died Lewes, East Sussex 17 December 1996.