The use of radiography for the examination of paintings began shortly after Roentgen's discovery of X-rays, but many years passed before museums were able to install the equipment necessary for the work. In between times radiography was carried out for both individuals and galleries by many people, particularly doctors. One of these was Dr. A. Faber who undertook in 1914 a scientific study of the method and published an analysis of the absorption characteristics of various pigments and of paintings with superimposed layers. Faber took out a patent on the method which had the effect of seriously interrupting the use in Germany of X-rays in this field between 1920 and the early 1930's. The article describes more fully this story and the consequences of the patent.