easily read. In order to avoid the initial error of Anquetin
and since at the beginning of my career I did not have free
access to the treasures of the museums), I entered the field of
restoration with the aim of surrounding myself with works,
or fragments of works, which had escaped re touching.
At this time, examinations on a scientific basis were seriously undertaken, Edmund Bayle, director of the Labora- toire de l'Identite Judiciaire, Paris, was deeply interested in this sort of' study and I soon became his visual expert. This enabled me to penetrate into the maze of modern scientific techniques. X-rays and photographs under ultra-violet and infra-red rays revealed the condition of a painting with a fair degree of accuracy and showed the consequences of repainting. But they did not present valuable indications that could lend to the reconstruction of the chemical composition. In other words, these methods were still too limited to enable us to discover what actual painting mediums might have been involved. Nor could spectral analysis (since it is concerned only with mineral matters) be of any value either in determining the composition of a varnish or medium. And from such data as this method does give it would be unwise to attempt any conclusive deductions, because the volatile matters in the varnishes have long since evaporated. Further confusion is encountered here through the fact that the restorers, through whose hands the painting may have passed, would, in removing old varnish from the painting, have contributed particles of foreign matter from the solutions used in their work. These particles would be revealed by spectral analysis in such a way that they would become confused with the material in the picture itself. So it will be seen that this kind of study can be very misleading if it is not undertaken with a previous knowledge of its difficulties.
One of the most valuable means of examination proved to be the use of photographs under a raking light. This method too, however, would only serve with real efficiency in the case of pictures that had not been worked over by restorers, for here again foreign matters would have been added to the original material. This is an easy method to use and possesses the great merit of in no way endangering the painting itself.