department moved the focus for the development of conservation theory and practice from Germany to Britain, and made the latter a prime force in this fledgling field. In 1956 Plenderleith wrote a significant handbook called The Conservation of Antiquities and Works of Art, which supplanted Rathgen's earlier tome and set new standards for the development of art and conservation science. In the United States, the development of conservation of cultural heritage can be traced to the Fogg Art Museum, and Edward Waldo Forbes, its director from 1909 to 1944. He encouraged technical investigation, and was Chairman of the Advisory Committee for the first technical journal, Technical Studies in the Field of the Fine Arts, published by the Fogg from 1932 to 1942. Importantly he also brought onto the museum staff chemists. Rutherford John Gettens was the first of such in the US to be permanently employed by an art museum. He worked with George L. Stout, the founder and first editor of Technical Studies. Gettens and Stout co-authored Painting Materials: A Short Encyclopaedia in 1942, reprinted in 1966. This compendium is still cited regularly. Only a few dates and descriptions in Gettens' and Stout's book are now outdated. George T. Oliver, of Oliver Brothers Art Restoration and Art Conservation-Boston (Est. 1850 in New York City) invented the vacuum hot table for relining paintings in 1920s; he filed a patent for the table in 1937. Taylor's prototype table, which he designed and constructed, is still in operation. Oliver Brothers is believed to be the first and the oldest continuously operating art restoration company in the United States. The focus of conservation development then accelerated in Britain and America, and it was in Britain that the first International Conservation Organisations developed. The International Institute for Conservation of Historic and Artistic Works (IIC) was incorporated under British law in 1950 as "a permanent organization to co-ordinate and improve the knowledge, methods, and working standards needed to protect and preserve precious materials of all kinds." The rapid growth of conservation professional organizations, publications, journals, newsletters, both internationally and in localities, has spearheaded the development of the conservation profession, both practically and theoretically. Art historians and theorists such as Cesare Brandi have also played a significant role in developing conservation science theory. In recent years ethical concerns have been at the forefront of developments in conservation. Most significantly has been the idea of preventive conservation.