ROENTGENOTHERAPY as a local treatment to the joints in chronic arthritis was begun by us over twelve years ago. We were prompted to institute this form of treatment after reading the early optimistic reports of Kahlmeter1 in Sweden and of Scott2 in London. At first the treatments were given with great caution. After a number of unexpected successes and an equal number of failures, a general plan of treatment for certain articular lesions in chronic arthritis was developed. During this time we learned to expect certain effects in the joints, and by trial and error we found some of the . . .