The use of the roentgen ray in the treatment of rheumatic diseases is not new. Soon after the therapeutic employment of roentgen rays in the field of medicine, reports of their effect on diseases of the joints began to appear. In 1898 Sokolow1reported improvement of 4 4 patients with arthritis he had treated with roentgen radiation. Stenbeck2(1898) treated 52 patients, most of whom he said were "improved." For the following twenty-five years numerous reports dealing with this subject appeared scattered in the literature. Increased interest in this form of therapy developed about 1925 when Staunig3reported generally good results from treatment of 400 patients with arthritis deformans, and Kohler4stated that considerable improvement had occurred in 100 patients with arthritis deformans and spondylitis. In the following year Kreuzwald5discussed his experience in treating 100 patients, of whom 87 per cent were said to