When I saw the names of the distinguished men who had preceded me in this pleasant duty, I felt very humble. I realised what a very great honour you have done me by inviting me to give this address; but if I am ill-equipped in regard to knowledge I can claim one attribute which might qualify me for the task. I realise with great thankfulness the immense debt which we as surgeons owe to Radiologists, Radiotherapists and Physicists. With out you we should indeed be lost. If, therefore, I fail on the score of intellectual stature I exceed in gratitude and this must be my title deed to your attention.When my father was a student at Guy's Hospital X rays had just been discovered. The hospital invested in an early model of an X-ray machine, with which quite satisfactory pictures were taken after relatively prolonged exposure of both patient and radiologist. The sphere of usefulness of these simple X-ray photographs was confined not so much to the diagnosis of fractures, because unless the fracture was obvious clinically it might not have shown up on the X-ray, but to seeing whether the fragments were in approximation and that the alignment of the bone was roughly correct. Some foreign bodies could be shown up by these early machines, but these were heavy metallic foreign bodies, bullets from the Boer War, and even some long-standing fragments from the Indian Mutiny and the Crimea, discovered within the persons of Chelsea pensioners, who came up to the hospital smoking their clay pipes and anxious to see what the Sepoys and Russians had left inside them.